text:
|Publication number
|Publication type
|Application number
|Publication date
|May 10, 2011
|Filing date
|Mar 7, 2007
|Priority date
|Nov 29, 2006
|Fee status
|Also published as
|Publication number
|William H. Sauer, Shelley Marie Cazares, Dan Li
|Original Assignee
|Cardiac Pacemakers, Inc.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (190), Non-Patent Citations (24), Referenced by (3), Classifications (8), Legal Events (2)
|External Links: USPTO, USPTO Assignment, Espacenet
This application claims the benefit of Provisional Patent Application Ser. No. 60/861,594, filed Nov. 29, 2006, to which priority is claimed pursuant to 35 U.S.C. �119(e) and which is hereby incorporated herein by reference.
The present invention relates generally to cardiac devices and methods, and, more particularly, to identifying tachyarrhythmia episode types and delivering therapy to mitigate the identified tachyarrhythmia episode types.
Proper cardiac function relies on the synchronized contractions of the heart at regular intervals. When the heart is functioning normally, synchronized cardiac contractions are initiated at the sinoatrial node and the heart is said to be operating in normal sinus rhythm. However, if contractions of the heart become irregular or uncoordinated, or if the contraction rate is too fast or too slow, the heart rhythm is described as arrhythmic. Cardiac arrhythmia may be caused, for example, by disease processes or from aberrant electrical conduction patterns occurring in the heart tissue. Cardiac arrhythmia impairs cardiac pumping efficiency and some types of cardiac arrhythmia can be life threatening.
A cardiac arrhythmia that originates in an atrial region of the heart is denoted a supraventricular tachyarrhythmia (SVT). Atrial fibrillation and atrial flutter are examples of SVT. Both conditions are characterized by rapid, uncoordinated contractions of the atria resulting in hemodynamically inefficient pumping action.
Another example of SVT is sinus tachycardia, which is an increased heart rate due to exercise or a quick emotional response. In contrast to atrial fibrillation and atrial flutter, sinus tachycardia is characterized by rapid, coordinated contractions of the atria resulting in hemodynamically efficient pumping action, compensating for the increased strain placed upon the body during exercise or quick emotional responses. Whereas atrial fibrillation and atrial flutter are "abnormal" (yet not lethal), sinus tachycardia is "normal" (and also not lethal).
Cardiac arrhythmias originating in a ventricular region of the heart are denoted ventricular tachyarrhythmias. Ventricular tachycardia (VT) is characterized by rapid ventricular contractions and can degenerate into ventricular fibrillation (VF). Ventricular fibrillation produces extremely rapid, non-coordinated contractions of the ventricles. Ventricular fibrillation is fatal unless the heart is returned to sinus rhythm within minutes or even seconds.
Implantable cardiac devices, including pacemakers and implantable cardioverter/defibrillators (ICDs), and have been used to deliver effective treatment to patients with serious cardiac arrhythmias. Implantable cardiac devices may treat cardiac arrhythmias with a variety of tiered therapies. These tiered therapies range from delivering low energy pacing pulses timed to assist the heart in maintaining pumping efficiency to providing high-energy shocks to treat and/or terminate fibrillation. To effectively deliver these treatments, the cardiac device must first identify the type of arrhythmia that is occurring, after which appropriate therapy may be delivered to the heart.
Some tachyarrhythmias are caused by abnormal cardiac tissue that creates short circuits in the electrical conduction pathways of the heart. Ablation is a therapeutic procedure that destroys the abnormal tissue to prevent or reduce recurrence of these types of tachyarrhythmias. Ablation may be used in conjunction with an ICD to reduce the number of shocks delivered to the heart to terminate VT or VF.
Methods and systems that facilitate identification of the causes of tachyarrhythmia episodes aid in determining appropriate therapies to treat the disorders causing the episodes. The present invention fulfills these and other needs.
The present invention is directed to methods and systems for identifying tachyarrhythmia episode types and delivering therapy to mitigate the identified tachyarrhythmia episode types. One embodiment is directed to a method of operating a cardiac system. Electrogram signals of cardiac activity are sensed and stored by an implantable cardiac device. Tachyarrhythmia episodes are detected using the electrogram signals. Tachyarrhythmia episode types are identified based on characteristics of the stored electrogram signals. In preparation for performing ablation, a tachyarrhythmia episode is induced. The features of the induced tachyarrhythmia episode are compared to characteristics of the identified episode types. A similarity is indicated between the induced tachyarrhythmia episode and at least one of the episode types identified from the stored electrogram signals to facilitate performing the ablation.
The characteristics of the tachyarrhythmia episodes of each episode type are associated with a conduction pattern of the episode type. The characteristics may involve one or more morphological characteristics and/or one or more interval characteristics of the tachyarrhythmia episodes.
In a further approach, the number of tachyarrhythmia episodes associated with each episode type are counted and displayed. The episode types may be ranked, where the rank of an episode type corresponds to a tachyarrhythmia burden of the episode type. The criteria used for the ranking is user programmable.
Ablation may be performed to prevent or mitigate future occurrences of one or more of the identified episode types. Episode types identified from tachyarrhythmia episodes stored before ablation may be compared to episode types identified from tachyarrhythmia episodes stored after ablation to confirm success of the ablation.
The number of distinct episode types may be determined algorithmically by an implantable or patient-external device or may be determined by a human analyst. In one implementation, after arranging the episodes in an order, the human analyst may identify one or more boundary episodes between the episode types. The tachyarrhythmia episodes may be grouped into episode types based on the boundary episodes.
In one implementation, a far field electrogram signal and a near field electrogram signal are sensed and stored. The characteristics identifying tachyarrhythmia episode types comprise morphological characteristics determined using the far field signal and the near field signal. In another implementation, a plurality of far field electrogram signals and a plurality of near field electrogram signals are sensed and stored. The characteristics identifying tachyarrhythmia episode types are determined using at least one of the far field signals and at least one of the near field signals.
In another approach, exit sites of the identified episode types are determined using the electrogram signals.
Another embodiment of the invention is directed to a cardiac system. The system includes an implantable sensing system and memory configured to sense and store electrogram signals. A tachyarrhythmia detector detects tachyarrhythmia episodes using the electrogram signals and determines characteristics of the tachyarrhythmia episodes from the electrogram signals. A data processor identifies episode types based on the characteristics of the tachyarrhythmia episodes. The data processor also determines a similarity between a tachyarrhythmia episode induced in preparation for performing ablation and at least one identified episode type. A display presents information related to the similarity between the induced tachyarrhythmia episode and the at least one identified episode type to facilitate performing the ablation.
The characteristics used to identify the episode types may include morphological characteristics or interval characteristics of the electrogram signals. The data processor may be configured to determine a number of distinct episode types and/or may discriminate a first type of ventricular tachyarrhythmia episode from a second type of ventricular tachyarrhythmia episode.
According to various implementations, the data processor may count the tachyarrhythmia episodes of the various episode types and/or may rank the episode types according to the tachyarrhythmia burden of the episode types.
In some implementations, the sensing system includes a first pair of cardiac electrodes configured to sense a far field electrogram signal and a second pair of cardiac electrodes configured to sense a near field electrogram signal. The tachyarrhythmia detector determines the characteristics of the tachyarrhythmia episodes using the far field electrogram signal and the near field electrogram signal.
In some implementations, the sensing system includes a plurality of far field cardiac electrode pairs, each far field electrode pair configured to sense a far field electrogram signal, and a plurality of near field cardiac electrode pairs, each near field electrode pair configured to sense a near field electrogram signal. The tachyarrhythmia detector determines the characteristics of the tachyarrhythmia episodes using at least one of the plurality of far field electrogram signals and at least one of the plurality of near field electrogram signals.
The data processor may be further configured to determine an exit site of one or more of the episode types based on the sensed and stored electrogram signals and/or may identify the exit site through comparison of the characteristics associated with a particular episode type to electrogram signals of paced beats.
The above summary of the present invention is not intended to describe each embodiment or every implementation of the present invention. Advantages and attainments, together with a more complete understanding of the invention, will become apparent and appreciated by referring to the following detailed description and claims taken in conjunction with the accompanying drawings.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail below. It is to be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
In the following description of the illustrated embodiments, references are made to the accompanying drawings forming a part hereof, and in which are shown by way of illustration, various embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized, and structural and functional changes may be made without departing from the scope of the present invention.
Tachyarrhythmias such as ventricular tachycardia (VT) or premature ventricular contractions (PVCs) can trigger ventricular fibrillation (VF) and sudden cardiac death. Implantable cardiac devices, e.g., implantable cardioverter/defibrillators (ICDs) treat VT and/or VF by delivering therapy in the form of anti-tachycardia pacing (ATP) and/or high energy defibrillation shocks. An interventional cardiac electrophysiologist can use catheter ablation techniques to ablate abnormal tissue causing PVCs or VT which may result in a reduced need for ICD therapy.
Some tachyarrhythmia episodes exhibit consistent morphology or interval patterns that may be discerned from the electrograms (EGMs) sensed during the episodes. Tachyarrhythmia episodes exhibiting consistent EGM patterns may be identified as belonging to particular episode types based on characteristics evident in the cardiac electrical signals of the tachyarrhythmia episodes. For example, the cardiac signals of tachyarrhythmia episodes of a first episode type exhibit representative morphological or interval characteristics that are distinct from the morphological or interval characteristics of tachyarrhythmia episodes of a second episode type. In one implementation, analysis of the electrogram signals by an implantable or patient-external device may be used to discriminate between distinct ventricular tachyarrhythmia episode types that exhibit consistent morphological or interval patterns. In addition, various types of ventricular tachyarrhythmias may be discriminated from episode types that are non-ventricular in origin, denoted herein as supraventricular tachyarrhythmias (SVTs).
Therapy to treat abnormal cardiac rhythms, including ablation, anti-tachyarrhythmia pacing (ATP), and/or defibrillation therapy, may be enhanced by identifying tachyarrhythmia episode types. For example, analysis of EGM signals collected by an ICD may be used to identify tachyarrhythmia episode types that historically have been experienced by the patient. Characteristics of an induced tachyarrhythmia episode may be compared to the identified episode types prior to ablation. Similarities between the induced tachyarrhythmia episode and the identified episode types may be used in determining or confirming ablation sites.
Episode types that are more problematic for the patient may include episode types that occur more frequently, are sustained, require therapy delivery for termination, are highly unstable, and/or that typically accelerate to VF. Embodiments of the invention are directed to methods and systems that determine the "tachyarrhythmia burden" as a way of ranking the tachyarrhythmia episodes types according to predetermined criteria. For example, the episode types may be ranked based on the number or frequency of occurrence of episode types. In some implementations, the episode types may be ranked based on factors such as the instability of the episode types, the amount of morphological disorganization of the episode type, the tendency of the episode type to accelerate to VF, the responsiveness of the episode type treatment such as ATP, and/or other factors.
One embodiment of the invention is illustrated in the diagram of
ICDs typically include cardiac electrodes that are in electrical contact with the myocardium and sense cardiac electrical signals that provide information about the depolarization status of the heart. Near field sensing yields signals that are most strongly representative of the activation signals that are present close to the site of an electrode pair.
Far field signals provide a more global view of the depolarization status of the heart than near field signals. For example, a sensed far field cardiac activation signal is effectively a superposition of a number of near field depolarization signals occurring within the heart that are associated with a cardiac contraction.
ICDs that include pacing capability typically include tip electrodes that are configured to make direct contact with the myocardium. Tip electrodes may be used for near field sensing of cardiac electrical signals. Far field sensing may be accomplished via various electrode pairs of an ICD, such as transvenous, endocardial, and/or epicardial electrodes (i.e., intrathoracic electrodes), and/or subcutaneous, non-intrathoracic electrodes, including can, header, and indifferent electrodes, and subcutaneous array or lead electrodes (i.e., non-intrathoracic electrodes). For example, electrode pairs suitable for far field sensing in an ICD may include RV-ring to RV-coil, RV-ring to SVC-coil, RV-ring to RA-ring, or may include sensing between two can electrodes, between a can electrode and an indifferent electrode, or between a can or indifferent electrode and a ring or coil electrode. ICDs capable of biventricular pacing provide additional near field and far field sensing capabilities. An electrode pair used for sensing cardiac electrical activity is referred to herein as a sensing vector. A sensing vector includes at least a pair of sensing electrodes, where each electrode of the pair may comprise multiple electrodes and/or multiple electrode elements used for sensing.
Returning now to
Tachyarrhythmia episode types are identified 130 through analysis of the EGM signal features of the tachyarrhythmia episodes. Each episode type is associated with a certain morphology or interval pattern of the EGM signal, which in turn is indicative of a conduction pattern associated with the episode type. Each episode type detected by the device is given a label, e.g., VT001 or PVC001.
During pre-ablation mapping, tachyarrhythmia episodes are induced 140. Features of the induced tachyarrhythmia episodes are compared to the characteristic features of the identified episode types. The similarity between the induced episode and at least one identified episode type is determined 150. The similarity may be displayed or otherwise indicated to facilitate the ablation.
Another process in accordance with embodiments of the invention is illustrated in the diagram of
One approach to detecting tachyarrhythmia episodes and classifying episode types is based on sensed event intervals, e.g., the P-P, P-R, R-P, or R-R timing intervals, and/or the atrial heart rate compared to ventricular heart rate along with the stability of the intervals and/or the onset characteristics of the intervals. Event intervals and rates may be identified as they occur and are compared to preset criteria, which must be met in order to identify a particular tachyarrhythmia type. U.S. Pat. No. 5,342,402, which is incorporated herein by reference, describes an interval based tachyarrhythmia detection and classification system and method.
In other approaches, the morphology of the EGM signal of a representative beat of the tachyarrhythmia episode may be analyzed to detect tachyarrhythmia and to classify tachyarrhythmia episode types. For example, morphological features extracted from the EGM signals may be compared to a template including corresponding features representative of a particular type of tachyarrhythmia. The features extracted from the EGM signal may include the time coordinates of local maxima and minima points of the cardiac signal, for example. If the signal features are sufficiently similar to the template features, the tachyarrhythmia episode may be identified as the episode type represented by the template. Additional details related to extraction of features points from cardiac signals and the use of such feature points to discriminate between various cardiac rhythms is described in commonly owned U.S. Pat. Nos. 6,266,554 and 6,449,503 which are incorporated herein by reference.
In yet another embodiment, the electrogram signal characteristics used to identify tachyarrhythmia episode types are coefficients of Fourier or wavelet decomposition of a composite cardiac beat signal for the episode. In one implementation, the composite beat signal of an episode is transformed into a number of signal wavelet coefficients using a wavelet transform, such as a Haar wavelet transform. The higher amplitude signal wavelet coefficients are identified and used as discriminating features of the episode. Additional details regarding the use of wavelet transformation to extract wavelet coefficients of cardiac electrogram signals are described in U.S. Pat. No. 6,393,316 which is incorporated herein by reference.
In yet a further embodiment, the features of the electrograms used to classify tachyarrhythmia episode types include areas between sections of an EGM signal (which may be a composite signal) and a baseline. For example, a group of consecutive peaks having the largest cumulative peak values are determined from the EGM signal. Features of the peaks such as areas of each peak, are determined and used to discriminate between different types of tachyarrhythmia. Additional features used for discriminating episode types may comprise the polarity and/or position of the peak. Further discussion regarding the extraction of peak information for use as discriminating features of a cardiac EGM signal are discussed in U.S. Pat. No. 5,779,645 which is incorporated herein by reference.
In some configurations, the episode types are ranked and the rankings are displayed. For example, the rankings may be displayed along with the number of episodes counted for each episode type. Counting or ranking the episode types provides a physician with an assessment of the tachyarrhythmia burden associated with each episode type. Furthermore, identifying and/or ranking tachyarrhythmia episode types may be used to provide the electrophysiologist with a pre-ablation map of PVC or VT pattern "signatures" of frequently occurring or otherwise problematic tachyarrhythmia episode types.
One implementation in accordance with embodiments of the invention involves ranking episode types based on the number of times a tachyarrhythmia episode of a particular episode type occurs. For example, the episode types may be ranked according to the number of tachyarrhythmia episodes counted for each episode type. The episode type with the highest count is ranked as having the highest tachyarrhythmia burden. The episode type having the lowest count is ranked lowest.
In other implementations, information in addition to the EGM signals may be stored and linked to the episode types. The additional information may be used in ranking the episode types. In these implementations, the episode types may be ranked according to onset characteristics, stability characteristics, duration, success or failure of therapies used for treatment, or other characteristics. The characteristics used for ranking may be programmable.
By identifying and labeling specific episode types, the electrophysiologist will also be able to identify supraventricular tachyarrhythmias (SVTs) that may be conducted aberrantly. If not identified, supraventricular tachyarrhythmias, which have their own characteristics, may cause an inappropriate shock. Therefore, identification of an SVT based on characteristics of the EGM would result in therapy inhibition the next time this SVT occurs. Using this implementation, specific therapies, or withholding of nominally programmed therapies, can be programmed according to the tachyarrhythmia identified. For example, an SVT that is conducted aberrantly (i.e. unlike the stored sinus rhythm template) can be identified by the device which can be programmed to inhibit therapy for the episode type. Similarly, a specific VT can be programmed to be treated with anti-tachycardia pacing even if the rate identifies it as a tachyarrhythmia in the VF zone. Similarly, tailored therapy with specific ATP sequences using a specific left ventricular, right ventricular, or biventricular stimulation or immediate shock delivery, regardless or rate can be assigned to any type of tachyarrhythmia type observed.
Information provided by ranking the episode types may be used by an electrophysiologist in performing ablation to prevent future occurrences of certain episode types. For example, it may be desirable to perform ablation to eliminate one or more episode types associated with the highest tachyarrhythmia burden. In another implementation, ranking the tachyarrhythmia episode types may be used by a physician to adjust the programmable settings of an ICD to enhance electrical stimulation therapies delivered by the device, or may be used for other therapeutic or diagnostic purposes. Information about the tachyarrhythmia episodes, including the rankings of the tachyarrhythmia episodes before and after ablation is performed and/or before and after the ICD settings are adjusted, may be displayed and/or compared.
Referring now to
The lead system 202 is used to sense cardiac electrical signals produced by the heart and to provide electrical energy to the heart under certain predetermined conditions to treat cardiac arrhythmias. The lead system 202 may include one or more electrodes used for pacing, sensing, and/or defibrillation. In the embodiment shown in
The ICD 200 and lead system 202 illustrated in
As illustrated in
The right ventricular lead system 204 illustrated in
In one configuration, the RV-tip electrode 212 referenced to the can electrode 208 may be used to implement unipolar pacing and/or near field sensing in the right ventricle. Bipolar pacing and/or sensing in the right ventricle may be implemented using the RV-tip 212 and RV-ring 211 electrodes. In yet another configuration, the RV-ring 211 electrode may optionally be omitted, and bipolar pacing and/or sensing may be accomplished using the RV-tip electrode 212 and the RV-coil 214, for example. The right ventricular lead system 204 may be configured as an integrated bipolar pace/shock lead. The RV-coil 214 and the SVC-coil 216 are defibrillation electrodes.
The left ventricular lead 206 includes an LV distal electrode 213 and an LV proximal electrode 217 located at appropriate locations in or about the left ventricle for pacing and/or sensing the left ventricle. The left ventricular lead 206 may be guided into the right atrium of the heart via the superior vena cava. From the right atrium, the left ventricular lead 206 may be deployed into the coronary sinus ostium, the opening of the coronary sinus 250. The lead 206 may be guided through the coronary sinus 250 to a coronary vein of the left ventricle. This vein is used as an access pathway for leads to reach the surfaces of the left ventricle which are not directly accessible from the right side of the heart. Lead placement for the left ventricular lead 206 may be achieved via subclavian vein access and a preformed guiding catheter for insertion of the LV electrodes 213, 217 adjacent to the left ventricle.
Unipolar pacing and/or near field sensing in the left ventricle may be implemented, for example, using the LV distal electrode 213 referenced to the can electrode 208. The LV distal electrode 213 and the LV proximal electrode 217 may be used together as bipolar sense and/or pace electrodes for the left ventricle. The lead system 202 in conjunction with the device 200 may provide bradycardia pacing therapy to maintain a hemodynamically sufficient heart rate. The left ventricular lead 206 and the right ventricular lead 204 and/or the right atrial lead and the left atrial lead may be used to provide cardiac resynchronization therapy such that the ventricles and/or atria of the heart are paced substantially simultaneously or in phased sequence separated by an interventricular or interatrial pacing delay, to provide enhanced cardiac pumping efficiency for patients suffering from congestive heart failure.
The right atrial lead 205 includes a RA-tip electrode 256 and an RA-ring electrode 254 positioned at appropriate locations in the right atrium for sensing and pacing the right atrium. In one configuration, the RA-tip 256 referenced to the can electrode 208, for example, may be used to provide unipolar pacing and/or sensing in the right atrium. In another configuration, the RA-tip electrode 256 and the RA-ring electrode 254 may be used for bipolar pacing and/or sensing.
The ICD 200 can be programmed to acquire the near field and/or far field cardiac signals sensed via electrodes 211-218, 254, 256, 208 and 209 during cardiac tachyarrhythmia episodes. Near field sensing vectors include, for example, the signals recorded from a tip electrode. Far field sensing vectors may include the bipolar signals recorded from the ring of a pacing lead to the device canister and/or defibrillation coils. The number of far field signals recorded is a function of the number of electrodes included in the system.
The device circuitry includes a memory 245 for storing cardiac signals and/or other data, including data related to tachyarrhythmia episodes. The ICD 200 also includes communication circuitry (not shown) to facilitate wireless communication with a patient-external device, such as a device programmer and/or remote server. The cardiac signals and/or other data may be acquired and stored in the ICD memory for a period of time. The stored signals and data may be downloaded periodically or on command to a remote system via the communications circuitry.
Although the ICD 200 is described as an implantable therapy device, the device that acquires the episode data need not be implantable and need not have therapy capability. For example, the principles of the invention are also applicable using a cardiac monitor that is patient-external and only acquires and optionally stores cardiac signals without delivering therapy.
Referring now to
The system 300 includes implantable electrodes 305 coupled to sensing circuitry 310 through a switch matrix 325. The electrodes 305 may be disposed implantably at multiple locations within, on, or about the heart, may be disposed subcutaneously, e.g., on the surface of an implantable device housing, and/or may be arranged patient-externally on the surface of the patient's skin, as previously described. Various combinations of the electrodes coupled via the switch matrix 325 to the sensing circuitry 310 may be used to sense near field and/or far field cardiac electrical signals.
Control processor 340 may include circuitry for triggering data acquisition before, during and/or after the occurrence of a cardiac tachyarrhythmia episode. Collection (i.e., acquisition and storage) of cardiac signal data and optionally other data only during time windows around episode occurrences may be useful in devices where memory is limited. Alternatively, if the system includes sufficient memory, cardiac signals may be continuously collected for later analysis to detect episode occurrences. Alternatively, the device may continuously or intermittently transmit the data in real time as it is acquired to a remote device.
The system may optionally have therapy capability. In therapy-capable implementations, the control processor 340 controls therapy circuitry such as pulse generator circuitry 330. The pulse generator circuitry 330 has the ability to generate pacing pulses for treating bradycardia and/or the ability to generate anti-tachyarrhythmia pacing pulses and/or high energy defibrillation or cardioversion shocks used for terminating dangerous tachyarrhythmias such as VF.
In various embodiments, the system acquires and stores cardiac signals sensed via the electrodes 305 continuously or during a time window before, during, and/or after cardiac tachyarrhythmia episodes or during other times, such as following LV or RV pacing. In one example, cardiac signals from each cardiac episode experienced by the patient are acquired along with one or more of cardiac marker channel signals. The signals associated with the episode are stored in the memory 345 and may be time and date stamped.
In one implementation, the cardiac electrodes 305, sense circuitry 310, memory 345, and control processor 340 are components of an implantable device, e.g., ICD 307. In this implementation, the episode data collected during one or more cardiac episodes may be transferred to a patient-external device 360 to facilitate interaction with a human analyst. For example, the ICD 370 may include a transmitter/receiver 350 configured to transmit the stored episode data to the patient-external device 370 automatically, periodically, or on command to a transmitter/receiver 362 of the patient-external device 360. In addition, data and/or program commands useful for controlling the operation of various components of the ICD 370 may be transmitted via the patient external device 360 and stored in the memory 345 of the ICD 370.
The patient external device 360, e.g., device programmer or remote server, optionally includes a tachyarrhythmia detector 364 configured to detect tachyarrhythmia episodes from the cardiac electrical signals downloaded from the ICD 370. The tachyarrhythmia detector 364 is further configured to determine characteristics of the tachyarrhythmia episodes from the electrogram signals. A data processor 366, optionally included in the patient external device 360, identifies episode types based on the morphological or interval characteristics of the tachyarrhythmia episodes. The number of different episode types into which the sensed tachyarrhythmia episodes are grouped may be determined algorithmically by the data processor 366, or may be input by a user. Although
Arrhythmia induction circuitry 390 is used to induce one more tachyarrhythmia episodes, such as during a pre-ablation procedure. Electrograms of the induced tachyarrhythmias are sensed via the cardiac electrodes 305 and sense circuitry 310. Features of the induced tachyarrhythmia episodes are compared to those of the identified episode types. If the features of an induced tachyarrhythmia episode are similar to the features associated with an identified episode type, then this information may be used by the electrophysiologist to inform the ablation process. For example, the electrophysiologist may be particularly interested in identifying cardiac sites that are responsible for episode types producing the greatest tachyarrhythmia burden. Ablation of these sites may be used to reduce or eliminates a most frequently occurring episode type or an episode type that is particularly problematic for the patient.
In some embodiments, the data processor 366 includes counter circuitry configured to count the number of tachyarrhythmia episodes for each episode type. The data processor 366 may optionally rank the episode types based on the number of tachyarrhythmia episodes counted for each episode type or based on other information. The count or rank of tachyarrhythmia episodes for each episode type and/or information related to similarity between induced tachyarrhythmia episode and identified episode types is transferred to a display device 368.
The programmer 400 includes a graphics display screen 420, e.g., LCD display screen, that is capable of displaying graphics, alphanumeric symbols, and/or other information. For example, the programmer 400 may graphically display one or more of the cardiac signals downloaded from the ICD on the screen 420. The display screen 420 may include touch-sensitive capability so that the user can input information or commands by touching the display screen 420 with a stylus 430 or the user's finger. Alternatively, or additionally, the user may input information or commands via a keyboard 440 or mouse 450.
The programmer 400 includes a data processor 460 including software and/or hardware for managing cardiac episode data stored in the memory 465 of the programmer 400. In one implementation, cardiac episode data is received from an ICD via communications circuitry 466 of the programmer 400. The data processor 460 identifies cardiac episode types based on one or more discriminating features of the tachyarrhythmia episodes detectable in the cardiac episode data. The data processor may compare features of induced tachyarrhythmia episodes to those of identified episode types. The tachyarrhythmia episodes associated with each episode types may be counted and/or ranked by the data processor as previously described. Information related to the comparison of induced tachyarrhythmia episodes to identified episode types, tachyarrhythmia episode count and/or rankings are presented to the user via a display screen 420.
In one embodiment, the data processor 460 may algorithmically group the stored tachyarrhythmia episodes having similar characteristics into episode types. The characteristics used for grouping the episode types may be identified by the user or may be identified by the data processor 460, for example.
In some embodiments, the groupings of similar episodes may be determined by a user and entered via the keyboard 420, the mouse 450, or stylus 430 for touch sensitive display applications. Methods and systems for grouping tachyarrhythmia episodes are described in U.S. Pat. No. 6,091,990 which is incorporated herein by reference.
In one embodiment, the data processor 460 or other remote patient-external device, processes tachyarrhythmia episode data stored in the ICD and downloaded to the remote device. The data processor 460 finds a tachyarrhythmia episode having a set of discriminating features, labels that episode as corresponding to an episode type and searches for additional episodes with discriminating features similar to the first episode type. If episodes having similar discriminating features are found in memory, the data processor 460 may count the number of similar episodes. The number of tachyarrhythmia episodes of a particular type may be displayed along with labels for the episode types on the programmer display 420.
ICDs are typically capable of acquiring cardiac EGM signals from multiple sensing vectors, including far field and near field sensing vectors. The morphological patterns present in the individual beat signals of a first tachyarrhythmia episode may be compared to the morphological patterns of a second one or more tachyarrhythmia episodes using information from both the far field and near field signals of the tachyarrhythmia episodes. In one implementation, the far field signal of a representative beat of the first tachyarrhythmia episode is aligned with the far field signal of a representative beat of a second tachyarrhythmia episode using fiducial points identified in the near field signals of the first and second tachyarrhythmia episode representative beats. After alignment, amplitude values of the representative beat signals are then compared to determine morphological similarity between the first and second tachyarrhythmia episodes.
In one example, predetermined feature points F1-F5 may be extracted from a representative or composite far field signal beat of the first tachyarrhythmia episode as illustrated in
The diagram of
The tachyarrhythmia episode signals are downloaded 620 to a device programmer or other remote patient-external computer. Features of the far field signal of a representative beat of a first tachyarrhythmia episode are extracted 630. The first tachyarrhythmia episode detected is labeled and counted as a new episode type. A next tachyarrhythmia episode is detected. A representative beat signal of the next tachyarrhythmia episode is aligned 640 with the representative beat of the first tachyarrhythmia episode using their corresponding rate channel fiducial points. The features of the far field signals of the tachyarrhythmia episodes are compared 650. If the features are similar 660, the next tachyarrhythmia episode is counted 670 as corresponding to the first episode type.
If the features of the next tachyarrhythmia episode are not similar 660 to the features of the first tachyarrhythmia episode, and there are more episode types to compare 680 to the tachyarrhythmia episode features, then the features of the tachyarrhythmia episode are compared to one or more additional episode types 690. If all the episode types have been compared to the tachyarrhythmia episode and none are similar, then the tachyarrhythmia episode is labeled and counted 685 as a new episode type. The process illustrated in the diagram of
While the labeling and counting process described in connection with
SVC Coil
RV coil (or ring), RV tip, LV
ring, or LV tip
RV coil (or ring), RV tip, LV
ring, or LV tip
RV coil
LV coil and LV tip
RV tip
LV coil and LV tip
The use of a multiple lead recording system for tachyarrhythmia episodes provides information that may be used to determine a more precise characterization of all tachyarrhythmias.
Analysis of the electrogram signals of a multi-lead ICD may also be performed to indicate exit sites of the various episode types in the same way that analysis of a 12-lead electrocardiogram can identify a PVC or VT site of origin to a region of the heart. Analysis of the vector on a far-field EGM could regionalize the site of origin of the PVC or VT to a specific location in either the left or right ventricle. In one embodiment of the invention, EGM signals acquired from the sensing vectors of a multi-lead biventricular ICD are analyzed to determine exit sites for each of episode type. A process for determining exit sites for one or more episodes types is illustrated by the diagram of
Location of PVC or VT exit site, e.g., lateral wall, apex, or non-septal site may be characterized by distinct patterns when compared to LV pacing, RV pacing and sinus rhythm. For example, if a particular episode type morphology resembles LV pacing, the exit site for that episode type can be assumed to be near the LV pacing site. The process described above may be modified to alternatively or additionally include analysis of signals produced by LV pacing, RV pacing, and sinus rhythm to determine the exit site for the tachyarrhythmias.
In accordance with various embodiments, the number of episode types is algorithmically determined. For example, the episodes may be clustered using a genetic algorithm, such as a K-means clustering algorithm. In one embodiment involving K-means clustering, each episode's N distinguishing features are expressed as an N-dimensional feature vector. The feature vectors of all episodes can be thought of as being plotted in N-dimensional space. Episodes similar in conduction pattern will be plotted close to each other while episodes having different in conduction pattern will be plotted farther from each other. The K-means clustering algorithm will automatically cluster the episodes into K groups, with each group represented by its mean feature vector and each episode assigned to the group with the closest mean feature vector.
In some embodiments, groups may be formed where a particular episode can be a member of only one group. In other embodiments, a particular episode may be a member in more than one group. For example, a fuzzy K-means clustering algorithm may be used to group the episodes. With conventional K-means clustering described above, an episode can belong to only one cluster as the conventional algorithm assigns to an episode one crisp membership value per cluster (equal to 0 if the episode is not a member of the cluster and 1 if the episode is a member of the cluster). In contrast, with the fuzzy algorithm, an episode can belong to several clusters, as the fuzzy algorithm assigns to an episode one membership value per cluster ranging from 0 to 1. These membership values specify the episode's degree of membership into each cluster.
Note that in the above-described embodiments, the number of clusters is first determined before using the genetic K-means algorithm to cluster the episodes. In some implementations, the physician specifies K which is the number of groups or clusters. In other implementations, the processor uses a predetermined number as K. In yet other implementations, the processor determines the value of K by partitioning the N-dimensional space based upon the density of the feature vectors in the space. In a further implementation, the processor determines the value of K by partitioning the N-dimensional space based upon a matrix of similarity measurements comparing each feature vector to each other.
In one scenario, the processor may use a probability function such as a probability density function (PDF) or a cumulative distribution function (CDF) to determine the number of clusters. This technique is described with reference to determining the number of rate zones in commonly owned U.S. patent application Ser. No. 11/506,253, filed Aug. 18, 2006 which is incorporated herein by reference. The same principle is applicable to determining the number of clusters based on the PDF or CDF formed using discriminating features or mean feature vectors of the episodes. The number of groups may be determined from the morphology of the CDF or PDF as is described for determining the number of rate zones in the previously incorporated patent application.
In yet other embodiments, the episodes are first ordered and are then grouped. For example, the episodes may first be ordered based on the value of one discriminating feature or may be ordered based on N discriminating features. A physician may identify groups of the ordered episodes. In one scenario, the physician may identify episodes, denoted herein as border episodes. The border episodes may have one or more discriminating features that appear to form a natural division between one group and another group, for example. After determination of the number of episode types, counting and/or ranking the episode types may proceed as described above.
As the amount of information collected and stored in ICDs increases, the interpretation of data becomes more complex and time consuming. The present invention provides methods and systems for arranging cardiac episodes based on discriminating features of the episode data. The processes described herein allow a physician to more easily identify cardiac episodes types and determine the VT burden associated with different episode types. The methods of the present invention allow a physician to identify the number and/or frequency of different types of cardiac episodes experienced by the patient. Data processing algorithms used to identify episode types, count tachyarrhythmia episodes associated with episode types and rank episode types to determine the VT burden of the various episode types may operate in an implantable or patient-external device that also acquires the episode data. In another version, an implantable or non-implantable device may acquire the episode data and the arrangement and/or labeling of the data may be performed by a device programmer or a remote server, for example.
Various modifications and additions can be made to the preferred embodiments discussed hereinabove without departing from the scope of the present invention. Accordingly, the scope of the present invention should not be limited by the particular embodiments described above, but should be defined only by the claims set forth below and equivalents thereof.
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|Citing Patent
|Filing date
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|Sep 13, 2011
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|Cardiac stimulator with stimulation success monitoring
|Jun 29, 2007
|Aug 27, 2013
|Pacesetter, Inc.
|Methods and systems for trending ST segment changes over time
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|Thomas Doerr
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|U.S. Classification
|600/518, 606/42, 600/509, 607/14
|International Classification
|Cooperative Classification
|European Classification
|Sep 24, 2007
Owner name: CARDIAC PACEMAKERS, INC., MINNESOTA
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Lexus To Replace Emergency Trunk Release On ES, GS, IS Models, Gallery 1
Lexus ES 350 Related News
One week before a new U.S. president is sworn into office, a second major automotive scandal--the one involving Takata's fatally flawed airbags--is coming to an end. But while today's agreement may wind down the government's investigation of the Japanese supplier, the recall and repair of vehicles...Read More»
Toyota is recalling roughly 31,000 Toyota Avalon, Avalon Hybrid, Lexus ES 300h, ES 350 vehicles from the 2013, 2014, and 2015 model years. According to a statement from the automaker, the automated braking systems in some of those vehicles may malfunction, increasing the risk of accidents and...Read More»
Yesterday, our colleagues at Motor Authority predicted that today's press event with Toyota president Akio Toyoda would include an announcement that the company is moving production of some Lexus vehicles to the U.S. Move over, Walter Mercado, because it appears that our team was right. At a press...Read More»
Score two for Consumer Reports. Earlier this week, the Environmental Protection Agency said that it would investigate fuel efficiency on the 2013 Ford C-Max and Ford Fusion Hybrid -- in part because Consumer Reports had been so vocal in its criticism of those vehicles' claims. Now, the magazine's...Read More»
The 2013 Lexus ES and GS luxury sedans may have a defective emergency interior trunk release that could be a trap risk for trunk occupants, according to Consumer Reports. The flaw was discovered by accident by Jake Fisher, one of the publication's testers, during an evaluation of the two...Read More»

subset: commoncrawl


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Dean Markley Strings!
Among the artists who have turned to Dean Markley's strings are guitar hero Yngwie Malmsteen, session bass player Will Lee, George Strait and his entire band, Joe Bonamassa, Mike Mushok with Staind, Phoenix with Linkin Park, Sarah McLachlan, Metallica, Korn, Fallout Boy, Toby Keith, Misfits, George Strait, Michael Anthony, Dick Dale, The Edge-U2, Avril Lavigne, Atreyu, Fishbone, Neil Young, Queens of The Stone Age - we could go on and on. If you want to get the most out of your ax, put on a set of Dean Markley Strings and join the club.
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text:
Irrigation scheduling is an essential part of conserving landscape water use. WIM pursues these and other steps to assure that watering is properly scheduled for each landscape's specific conditions.
The need for water changes with the weather. Evapotranspiration (ET) is the sum of the water lost from the soil surface (evaporation) and the water used by the plants (transpiration).
When calculating a base watering schedule, Reference Evapotranspiration (ETo) is often used. Reference ET can be estimated from a variety of sources, including local weather stations (such as WIM's), computer services, historical data, or simply measuring the depth of water evaporated from an open pan.
Peak ET Rates of Selected U.S. Cities
ET Connection - by state
This is used to determine the water needs for each type of plant material.
This helps identify the amount of applied water needed to overcome the inefficiencies involved in the application process.
A more efficient, site-specific irrigation system requires the application of less water applied to get the same result as system that's designed to operate less efficiently.
Calculating Precipitation Rates (PR) helps determine how quickly the water is applied per unit of time. Precipitation Rate is a critical design factor, as sprinklers can easily apply water faster than the soil's intake rate.
Precipitation Rates can be calculated based on two different formulas.
- Gross Precipitation Rate: based on the total flow of the irrigation station (or zone), not accounting for water losses that occur between sprinklers and the landscape.
PRgross (in./h) = 96.3 x Q / A
PRgross = Net precipitation rate (in./h)
Q = Station flow rate (gpm)
A = Station area (ft2)
96.3 = Conversion factor
- Net Precipitation Rate: the measure of the amount of water that reaches the landscape, accounting for the losses that occur between the sprinkler and the landscape.
PRnet (in./h) = CVavg x 3.66 / TR x CDA
PRnet = Net precipitation rate (in./h)
CVavg = Average catch can volume (milliliters)
3.66 = Constant that converts milliliters to in.3 and minutes to hours
TR = Testing run times (minutes)
CDA = Catch device throat area (square inches)
This helps identify the needed frequency of irrigation and cycle/soak. Final recommendations are based on the site-specific analysis of:
- Soil type
- Infiltration rate
- Water holding capacity


text:
Merchant Account Services
Accept credit card payments and receive timely, automatic credit directly into your deposit account
Get a Merchant Services account (provided by First Data®) with Zions Bank and potentially increase sales by accepting Visa®, MasterCard®, Discover, American Express®, Diners Club and JCB cards. Merchant account services offers:
- Competitive merchant payment processing rates
- Retail, phone, Internet and e-commerce solutions
- Wireless merchant payment processing, including for iPad®, iPhone® and Android devices
- EMV ready
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- Web-based reporting tools
- Help Desk support 24/7 x 365 through First Data
- A dedicated Merchant Account Services team that provides custom payment processing options
- Check verification
Have You Heard About EMV?
EMV, or EuroPay, MasterCard and Visa, is the global standard for card present payment processing technology—and it's coming to the US.
What You Need to Know About EMV
Discover More Accounts Receivable Financing Solutions
Learn about other services for collections and receivables offered by Zions Bank, including ACH Origination and Anytime Deposits by speaking with a representative. Simply call 800-726-7503 or fill out the form.


text:
- Eczema
- Overview
- Types of Eczema
- Treatment
- Child Eczema
- Resources
- Eczema Products
- Get Involved
- Research
Neurodermatitis, also known as lichen simplex chronicus, is a condition that appears on the skin and is similar to atopic dermatitis.
Neurodermatitis appears in patches. As a result of frequent rubbing and scratching, these patches tend to be thick and scaly and can be found on the neck, scalp, shoulders, feet and ankles, and wrists and hands.
Like atopic dermatitis, the itchy areas can become thick, discolored and marked. Unlike atopic dermatitis, the specific patches tend to always be present while the rest of the skin remains healthy.
The cause of neurodermatitis is unknown, but certain triggers such as an insect bite and stress seem to play a role. In neurodermatitis, the nerves in the skin appear be overly ready to tell the brain that there is itch. Sometimes, neurodermatitis can occur with a skin allergy.
Not scratching and rubbing the affected areas is key to healing the skin. Cutting fingernails very short and applying ice or an anti-itch preparation can be helpful in preventing scratching.
In some situations, performing patch testing to look for allergens and then avoiding those substances can help.
Like atopic dermatitis, neurodermatitis benefits from moisturizers to calm and protect the damaged skin. Heavy moisturizers may also help protect the area from rubbing and scratching.
Covering the skin (also known as occlusion) with socks, gloves, and even gauze wraps may also help the skin heal by disrupting the itch-scratch cycle and allowing the moisturizer to deeply penetrate. Unna boots (gauze impregnated with zinc oxide paste) are particularly helpful for neurodermatitis.
Topical corticosteroid medication can help calm the inflammation and itch. Because the skin tends to be very thick and scaly in neurodermatitis, stronger steroids may be required.
In cases where corticosteroids are not appropriate, or when they have been used for a long time, a non-corticosteroid topical medication such as tacrolimus (Protopic) or pimecrolimus (Elidel) may be prescribed.
In severe cases, corticosteroids may be injected into the lesions to allow them to penetrate the thickened skin.
Medical images provided by Skinsight.com.


text:
[Date Index]
[Thread Index]
[Author Index]
Re: LogLogPlot trouble
Hi Nicola
> Hello,
> I've a very basic problem with the procedure
> LogLogPlot. The problem is that:
> I normally include the procedure with
> In[1]:=<<Graphics`Graphics`
> and this works fine. The problem is that I need
> to do a framed plot, so I type (for example):
> In[2]:=LogLogPlot[x^2,{x,0,5},Frame->True]
> So, Mathematica draws the plot and put the numbers
> on the axes (0.1, 0.01, 0.001 and so on, what is the
> "official" name?) both on the right and on the left,
> on the top and on the bottom. Now, this is a problem
> for me because I need a figure with these numbers
> also on the left and on the bottom (for publishing).
> There is some way to overwrite this behaviour of
> LogLogPlot, that is not the same of Plot (when
> "framed", Plot put numbers also where I would like
> them).
SetOptions[LogPlot, FrameTicks->{Automatic, Automatic, None, None}];
works for me. From memory, the order is {Bottom, Left, Top, Right}.
"Automatic" can be substituted with
* LogScale for logarithmic ticks
* PiScale for ticks in multiples/divisors of Pi
* LinearScale for the obvious
or any other function you want.
David Annetts _____________
http://www.ocs.mq.edu.au/~dannetts/ |C R C A M E T|
|_____ |
CRC for Australian Mineral |````` \ |
Exploration Technologies |`````/$\ |
Earth & Planetary Sciences |````/$$$\____|
Macquarie University, NSW 2109 |```/$$$/.....|
phone: +(1-61-2) 9850 9280, fax (1-61-2) 9850 8366 -------------


text:
'Gentleman' Mustache Series Raises Prostate Cancer Awareness
The annual initiative raises awareness on prostate cancer and men's health. 2011 celebrates the 'country gentleman' and 'life in the great outdoors' on film.
Movember–the mustache growing movement which raises awareness on prostate cancer and men's health issues–is back in 2011 with a touch of old-world style.
With its roots in Melbourne, the now global month-long challenge asks participants to skip the shave for thirty days and raise funds for men's health. This year's campaign takes a new tactic and highlights the 'country gentleman' and 'life in the great outdoors' in a series of short films.
The Movember Craft & Pride series captures:
Men with an appreciation of natural quality, craftsmanship and the simple pleasures in life [who] will be roaming proud across the country, sporting facial finery; a genuine and authentic mustache.
Over 1.1 Million 'Mo Bros' and 'Mo Sistas' have participated in the initiative to date. Watch the series trailer below:
Title image via CSMonitor


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RIR keeps both race weekends for 2013
Citizen Staff Reports 09/24/12
Officials from Richmond International Raceway today announced that the track will continue to host two NASCAR weekends in 2013. The events will be held April 26-27 and Sept. 6-7, with the September Sprint Cup Series race again serving as the final race before the 2013 Chase for the NASCAR Sprint Cup (the circuit's playoff equivalent).
The total financial benefit to the region as the result of both weekends – each of which includes a Nationwide Series and Sprint Cup Series race – is more than $300 million, according to RIR officials.
"Bringing NASCAR back to Richmond International Raceway twice next year is huge for everyone in Greater Richmond," said RIR President Dennis Bickmeier. "The money being pumped into our economy twice a year makes a big difference in the livelihood of the 1.3 million people who call Greater Richmond home. Hotels, restaurants, grocers and many other locally owned businesses will benefit when NASCAR flocks to RIR."
Tickets for the April NASCAR weekend go on sale Friday, Dec. 7. Fans who purchased tickets to this month's NASCAR weekend at RIR will be receiving renewal invitations in October. Guests who renew receive a savings on each ticket purchased, opportunity to keep their seats and may add or relocate seats before the general public.
For details, visit http://www.rir.com or call 1-866-455-7223.
New GRASP scholarships to aide winners with college debt and costs
Citizen Staff Reports 06/28/2017 EducationGeneral News
Fifteen Henrico County Public Schools students recently received a "2+2" scholarship from the non-profit organization GRASP (GReat Aspirations Scholarship Program, Inc.). In total, the newly created scholarships will help 71 students receive their baccalaureate degrees from a Virginia college or university with lower costs and less student debt.
The scholarship awards each winner $1,000 for his or her first year at a community college to cover the costs not covered by financial aid, such as books and computers. > Read more.
Long & Foster's Innsbrook, Short Pump offices participate in community service day event
Citizen Staff Reports 06/28/2017 BusinessGeneral News
Thousands of real estate agents and employees with Long & Foster Real Estate, including those at the Innsbrook and Short Pump offices in Glen Allen, Virginia, took part in the company's 20th annual Community Service Day June 7.
The Innsbrook and Short Pump offices chose to volunteer with Housing Families First on June 7. The organization's mission provides families experiencing homelessness with what they need to move to a stable housing situation. > Read more.
Network of Enterprising Women to award scholarships to local HS grads
Citizen Staff Reports 06/28/2017 BusinessEducationGeneral News
Three recent Henrico County high school graduates are among the 10 local students who will receive scholarships from the Network of Enterprising Women during the organization's monthly luncheon July 6. > Read more.
Crime Stoppers' Crime of the Week – June 26, 2017
Citizen Staff Reports 06/26/2017 General NewsPublic SafetyCrime of the Week
Richmond detectives need the public's help to identify the vehicle and suspects in the shooting incident of a 7-year-old boy and an adult male. Can you help Crime Stoppers solve this latest shooting?
The shooting occurred in the 1500 block of North 22nd Street in the Fairmount neighborhood of the city. Officers arrived and found the two victims near a bus stop. > Read more.
Richmond Montessori School earns VAIS reaccreditation
Citizen Staff Reports 06/26/2017 EducationGeneral News
Richmond Montessori School, an independent Montessori school for children ages 2 to 14, recently earned reaccreditation from the Virginia Association of Independent Schools. The VAIS accreditation program is one of only a few recognized at the national level through the National Association of Independent School's Commission on Accreditation and is also recognized and approved by the Virginia Board of Education through the Virginia Council for Private Education. > Read more.
Richmond Montessori School earns VAIS reaccreditation
Business in brief
James River Juvenile Detention Center to graduate its largest class
Henrico School Board selects redistricting Option E
'Senior Cool Care' program to help older adults in Metro Richmond
- More News
Print Edition
Jun. 15, 2017Current edition | Archive
Henrico County, Lewis Ginter to host Fourth of July events
Weekend Top 10
'Taste of Virginia' returning to Innsbrook Pavilion July 1
Restaurant Watch
Weekend Top 10
- More Entertainment
Obituary – Hoyle S. "Chick" Walters
Obituary – Janet Sue Vest
Obituary – Barbara Jean (Chilton) Crider
- More Obituaries
Guided tour of Malvern Hill planned as part of 'History at Sunset' series
Anthem LemonAid registration now open
YMCA to offer free weekend access for teens this summer
- More Community
Growing a grown-up: Part II
How to grow an adult
Make 'em take the pledge: no more snuff boxes!
- More Opinions
Code Lacrosse joins Richmond Strikers
5 Henrico student-athletes win scholarships at awards dinner
RIR to host playoff race in 2018
- More Sports
|June 2017
Place an Ad | More Classifieds
CalendarThe film "The Magnificent Seven" (PG-13) will play at 7 p.m. June 2 and at 2 p.m. and 7 p.m. June 3 at Henrico Theatre, 305 E. Nine Mile Rd. Tickets are $1 and can be purchased at the door. For details, call 328-4491. Full text


text:
Global wind power capacity increased by 22.5% in 2010 with 35.8 GW of new installations built, taking the total worldwide to 194.5 GW at end-2010 from 158.7 GW a year earlier, according to figures published Wednesday by the Global Wind Energy Council. A total of $65 billion was invested in the sector worldwide, the GWEC said.
But the overall growth rate was lower than the previous year for the first time in 20 years. In 2009, 38.6 GW was installed.GWEC noted that more than half of the new capacity built in 2010 came outside the traditional wind markets of Europe and North America, with China and other Asian nations witnessing a boom. China alone added 16.5 GW, to almost have the total new capacity.


text:
Free personalized radio that
plays the music you love
Sandra Bernhard
Selected Discography
Track List: Perfection EP
Track List: Everything Bad & Beautiful
Track List: I'm Still Here Damn It
Track List: Excuses For Bad Behavior - Part I
Track List: Without You I'm Nothing
Track List: I Love Being Me, Don't You?
Similar Artists
bbysmael you are everywhere lol:-)
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text:
Tragedy struck the Midwest when, on August 9, 2014, 18-year-old Mike Brown was gunned down at the hands of Darren Wilson, a police officer in Ferguson, Missouri.
At 12:01 p.m. on August 9, 2014, Officer Wilson drove up to Brown and his friend, Dorian Johnson, and ordered them to get out of the street and move onto the sidewalk. According to reports, a dispute between Brown and Wilson resulted in a physical confrontation, which began between Brown and Wilson through the window of the police vehicle. While still inside his police car, Wilson fired a single shot, after which Johnson and Brown ran. Wilson then exited his vehicle, fired at least six shots, several of which struck an unarmed Brown.
We caught up with hip hop icon LL Cool J for his thoughts on the tragedy and here's what he had to say:
"I jut think there's an educational process that has to take place with the police officers who are in the Black community or are sent to the Black community. It's a communication issue. They've got to know what our focus is about so that they don't feel so threatened. There has to be some dialogue and classes so they understand it It's ridiculous. Just because a kid is big and boisterous even if he's a little rough, that's not a reason to shoot him. It's unacceptable. Stop being afraid of our kids. Fear is the problem."


text:
OK folks,
I'm making a cast of my heavily modified Kelloggs Clone using the RTV silicone mold I made.
To make a good cast I want to use a gel-coat lining. Do I need to let it fully cure before applying the layers of fibreglass?
How thick should the layer be? Should I "paint" it on or use another method?
Your advice would be most appreciated!


text:
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