title: Continuous Stroke Unit Electrocardiographic Monitoring Versus 24-Hour Holter Electrocardiography for Detection of Paroxysmal Atrial Fibrillation After Stroke Detection of atrial high-rate events by continuous Home Monitoring: clinical significance in the heart failure–cardiac resynchronization therapy population Intermittent atrial fibrillation may account for a large proportion of otherwise cryptogenic stroke: a study of 30-day cardiac event monitors. Frequent Atrial Premature Beats Predict Paroxysmal Atrial Fibrillation in Stroke Patients: An Opportunity for a New Diagnostic Strategy Improved Detection of Silent Atrial Fibrillation Using 72-Hour Holter ECG in Patients With Ischemic Stroke: A Prospective Multicenter Cohort Study Cost-effectiveness of 7-day-Holter monitoring alone or in combination with transthoracic echocardiography in patients with cerebral ischemia Enhanced Detection of Paroxysmal Atrial Fibrillation by Early and Prolonged Continuous Holter Monitoring in Patients With Cerebral Ischemia Presenting in Sinus Rhythm Predictors of newly diagnosed atrial fibrillation in cryptogenic stroke: a cohort study. Subclinical atrial fibrillation and the risk of stroke. Holter monitoring in the diagnosis of stroke mechanism. Admitting Acute Ischemic Stroke Patients to a Stroke Care Monitoring Unit Versus a Conventional Stroke Unit: A Randomized Pilot Study Age-dependent yield of screening for undetected atrial fibrillation in stroke patients: the Find-AF study Detection of Paroxysmal Atrial Fibrillation by 30-Day Event Monitoring in Cryptogenic Ischemic Stroke: The Stroke and Monitoring for PAF in Real Time (SMART) Registry Unexpected low prevalence of atrial fibrillation in cryptogenic ischemic stroke: a prospective study A Structured Reading Algorithm Improves Telemetric Detection of Atrial Fibrillation After Acute Ischemic Stroke Comparison of detection of arrhythmias in patients with chronic heart failure secondary to non-ischemic versus ischemic cardiomyopathy by 1 versus 7-day holter monitoring. Atrial fibrillation in patients with cryptogenic stroke. Noninvasive Cardiac Event Monitoring to Detect Atrial Fibrillation After Ischemic Stroke: A Randomized, Controlled Trial Performance of a New Leadless Implantable Cardiac Monitor in Detecting and Quantifying Atrial Fibrillation Results of the XPECT Trial Impact of long-term ECG recording on the detection of paroxysmal atrial fibrillation in patients after an acute ischemic stroke. Paroxysmal atrial fibrillation in cryptogenic stroke: a case-control study. Pilot Randomized Trial of Outpatient Cardiac Monitoring After Cryptogenic Stroke Continuous monitoring versus HOLTER ECG for detection of atrial fibrillation in patients with stroke. Optimal timing and duration of continuous electrocardiographic monitoring for detecting atrial fibrillation in stroke patients. Diagnostic and therapeutic impact of ambulatory electrocardiography in acute stroke. 96 hours ECG monitoring for patients with ischemic cryptogenic stroke or transient ischaemic attack Atrial fibrillation and paroxysmal atrial fibrillation detection in patients with acute ischemic stroke. Cryptogenic Stroke and underlying Atrial Fibrillation (CRYSTAL AF): design and rationale. Multicenter randomized study of anticoagulation guided by remote rhythm monitoring in patients with implantable cardioverter-defibrillator and CRT-D devices: Rationale, design, and clinical characteristics of the initially enrolled cohort The IMPACT study. Detection of Paroxysmal Atrial Fibrillation in Acute Stroke Patients Twenty-eight day Holter monitoring is poorly tolerated and insensitive for paroxysmal atrial fibrillation detection in cryptogenic stroke. Detection of atrial fibrillation in patients with acute stroke. Cryptogenic stroke and underlying atrial fibrillation. Detection of paroxysmal atrial fibrillation with transtelephonic EKG in TIA or stroke patients
abstract: Background and Purpose — Cardioembolism in paroxysmal atrial fibrillation ( pxAF ) is a frequent cause of ischemic stroke . Sensitive detection of pxAF after stroke is crucial for adequate secondary stroke prevention ; the optimal diagnostic modality to detect pxAF on stroke units is unknown . We compared 24-hour Holter electrocardiography ( ECG ) with continuous stroke unit ECG monitoring ( CEM ) for pxAF detection . Methods — Patients with acute ischemic stroke or transient ischemic attack were prospect ively enrolled . After a 12-channel ECG on admission , all patients received 24-hour Holter ECG and CEM . Additionally , ECG monitoring data underwent automated analysis using dedicated software to identify pxAF . Patients with a history of atrial fibrillation or with atrial fibrillation on the admission ECG were excluded . Results — Four hundred ninety-six patients ( median age , 69 years ; 61.5 % male ) fulfilled all inclusion criteria ( ischemic stroke : 80.4 % ; transient ischemic attack : 19.6 % ) . Median stroke unit stay lasted 88.8 hours ( interquartile range , 65.0–122.0 ) .  ECG data  for automated CEM analysis were available for a median time of 64.0 hours ( 43.0–89.8 ) . Paroxysmal AF was documented in 41 of 496 patients ( 8.3 % ) . Of these , Holter detected pxAF in 34.1 % ; CEM in 65.9 % ; and automated CEM in 92.7 % . CEM and automated CEM detected significantly more patients with pxAF than Holter ( P<0.001 ) , and automated CEM detected more patients than CEM ( P<0.001 ) . Conclusions — Automated analysis of CEM improves pxAF detection in patients with stroke on stroke units compared with 24-hour Holter ECG . The comparative usefulness of prolonged or repetitive Holter ECG recordings requires further evaluation Aims Uncertainty exists over the importance of device-detected short- duration atrial arrhythmias . Continuous atrial diagnostics , through home monitoring ( HM ) technology ( BIOTRONIK , Berlin , Germany ) , provides a unique opportunity to assess frequency and quantity of atrial fibrillation ( AF ) episodes defined as atrial high-rate events ( AHRE ) . Methods and results Prospect i ve data from 560 heart failure ( HF ) patients ( age 67 ± 10 years , median ejection fraction 27 % ) patients with a cardiac resynchronization therapy ( CRT ) device capable of HM from two multi-centre studies were analysed . Atrial high-rate events burden was defined as the duration of mode switch in a 24-h period with atrial rates of > 180 beats for at least 1 % or total of 14 min per day . The primary endpoint was incidence of a thromboembolic ( TE ) event . Secondary endpoints were cardiovascular death , hospitalization because of AF , or worsening HF . Over a median 370-day follow-up AHRE occurred in 40 % of patients with 11 ( 2 % ) patients developing TE complications and mortality rate of 4.3 % ( 24 deaths , 16 with cardiovascular aetiology ) . Compared with patients without detected AHRE , patients with detected AHRE>3.8 h over a day were nine times more likely to develop TE complications ( P= 0.006 ) . The majority of patients ( 73 % ) did not show a temporal association with the detected atrial episode and their adverse event , with a mean interval of 46.7 ± 71.9 days ( range 0–194 ) before the TE complication . Conclusion In a high-risk cohort of HF patients , device-detected atrial arrhythmias are associated with an increased incidence of TE events . A cut-off point of 3.8 h over 24 h was associated with significant increase in the event rate . Routine assessment of AHRE should be considered with other data when assessing stroke risk and considering anti-coagulation initiation and should also prompt the optimization of cardioprotective HF therapy in CRT patients INTRODUCTION Despite extensive inpatient workup including telemetry monitoring , a significant proportion of stroke is classified as cryptogenic at hospital discharge . It is possible that a significant proportion of cryptogenic stroke is a result of intermittent atrial fibrillation ( AF ) . Thirty-day cardiac event monitors ( 30-DEM ) may increase the rate of AF detection compared with st and ard investigations that include a combination of electrocardiography , cardiac telemetry , and short-term Holter monitoring . METHODS Charts were review ed of patients who were admitted to a university stroke center or who were evaluated in the outpatient clinic during a 9-month period to determine whether the cause of stroke was cryptogenic . As a matter of protocol , such patients typically underwent 30-DEM and the results of such monitoring were documented along with the duration of inpatient cardiac monitoring if relevant . RESULTS In all , 218 patients with a diagnosis of ischemic stroke or transient ischemic attack were identified . Of the strokes , 36 ( 16.5 % ) were classified as cryptogenic . Twenty patients with cryptogenic stroke or transient ischemic attack were evaluated with 30-DEM . Four ( 20 % ) were found to have AF , and all 4 patients were treated with warfarin . CONCLUSION The 30-DEM changed the medical treatment of 20 % of patients with otherwise cryptogenic stroke because of the detection of intermittent AF despite no detection of AF on electrocardiography and inpatient telemetry monitoring in the majority of patients . Further prospect i ve studies of extended cardiac event monitors in the setting of cryptogenic stroke are warranted Background and Purpose — For patients having suffered ischemic stroke , the current diagnostic strategies often fail to detect atrial fibrillation as a potential cause of embolic events . The aim of the study was to identify paroxysmal atrial fibrillation in stroke patients . We hypothesized that patients with frequent atrial premature beats ( APBs ) recorded in 24-hour ECG will show more often atrial fibrillation when followed by repeated long-term ECG recordings than patients without or infrequent APBs . Methods — 127 patients with acute ischemic stroke and without known AF were enrolled in a prospect i ve study to detect paroxysmal AF . Patients were stratified according to the number of APBs recorded in a 24-hour ECG ( ≥70 APBs versus < 70 APBs ) . Subsequently , they all underwent serial 7-day event-recorder monitoring at 0 , 3 , and 6 months . Results — Serial extended ECG monitoring  identified AF in 26 % of patients with frequent APBs but only in 6.5 % when APBs were infrequent ( P=0.0021 ) . A multivariate analysis showed that the presence of frequent APBs in the initial 24-hour ECG was the only independent predictor of paroxysmal AF during follow-up ( odds ratio 6.6 , 95 % confidence intervals 1.6 to 28.2 , P=0.01 ) . Conclusions — In patients with acute ischemic stroke , frequent APBs ( ≥70/24 hours ) are a marker for individuals who are at greater risk to develop or have paroxysmal AF . For such patients , we propose a diagnostic workup with repeated prolonged ECG monitoring to diagnose paroxysmal AF Background and Purpose — Adequate diagnosis of atrial fibrillation ( AF ) , including paroxysmal AF , is an important part of stroke workup . Prolonged ECG monitoring may improve the detection of paroxysmal , previously undiagnosed AF ( unknown AF ) . Therefore , we evaluated systematic 72-hour Holter ECG monitoring to detect unknown AF for the workup of patients with stroke . Methods — Unselected survivors of a stroke or transient ischemic attack ( TIA ) without known AF were enrolled in a prospect i ve , multicenter cohort study of 72-hour Holter ECG monitoring in 9 German secondary and tertiary stroke centers between May 2010 and January 2011 . In addition to st and ardized workup of stroke pathogenesis according to the German Stroke Unit protocol , all patients underwent 72-hour Holter ECG monitoring directly after admission . All ECGs were central ly analyzed by 2 independent observers . We determined the proportion of unknown AF and compared the detection rates of 72- and 24-hour monitoring . Results — A total of 1135 patients were enrolled ( mean age , 67 years [ SD , 13.1 years ] , 45 % women , 29 % TIA ) .  Unknown AF was detected in 49 out of 1135 patients ( 4.3 % , [ 95 % confidence interval , 3.4–5.2 % ] ) by 72-hour ECG monitoring .  Unknown AF was diagnosed in 29 patients ( 2.6 % ) within the first 24 hours of ECG monitoring , and in 20 more patients only by 72 hours of ECG monitoring . The number needed to screen by 72-hour ECG was 55 patients ( 95 % confidence interval [ 35–123 ] ) for each additional AF diagnosis . Patients with unknown AF were significantly older and had more often a history of previous stroke . Patients with unknown AF were equally distributed within categories of pathogenesis according to Trial of Org 10172 in Acute Stroke Treatment ( TOAST ) classification . Conclusions — In unselected survivors of stroke or TIA , 72-hour ECG monitoring is feasible and improves the detection rate of silent paroxysmal AF Abstract Background and purpose Prolonged Holter monitoring of patients with cerebral ischemia increases the detection rate of paroxysmal atrial fibrillation ( PAF ) ; this leads to improved antithrombotic regimens aim ed at preventing recurrent ischemic strokes . The aim of this study was to compare a 7-day-Holter monitoring ( 7-d-Holter ) alone or in combination with prior selection via transthoracic echocardiography ( TTE ) to a st and ard 24-h-Holter using a cost-utility analysis . Methods Lifetime cost , quality -adjusted life years ( QALY ) , and incremental cost-effectiveness ratios ( ICER ) were estimated for a cohort of patients with acute cerebral ischemia and no contraindication to oral anticoagulation . A Markov model was developed to simulate the long-term course and progression of cerebral ischemia considering the different diagnostic algorithms ( 24-h-Holter , 7-d-Holter , 7-d-Holter after pre selection by TTE ) . Clinical data for these algorithms were derived from the prospect i ve observational Find-AF study ( IS RCT N 46104198 ) . Results Predicted lifelong discounted costs were 33,837 € for patients diagnosed by the 7-d-Holter and 33,852 € by the st and ard 24-h-Holter . Cumulated QALYs were 3.868 for the 7-d-Holter compared to 3.844 for the 24-h-Holter . The 7-d-Holter dominated the 24-h-Holter in the base-case scenario and remained cost-effective in extensive sensitivity analysis of key input parameter with a maximum of 8,354 € /QALY gained . Pre selecting patients for the 7-d-Holter had no positive effect on the cost-effectiveness . Conclusions A 7-d-Holter to detect PAF in patients with cerebral ischemia  is cost-effective . It increases the detection which leads to improved antithrombotic regimens ; therefore , it avoids recurrent strokes , saves future costs , and decreases quality of life impairment . Pre selecting patients by TTE does not improve cost-effectiveness Background and Purpose Diagnosis of paroxysmal atrial fibrillation is difficult but highly relevant in patients presenting with cerebral ischemia yet free from atrial fibrillation on admission . Early initiation and prolongation of continuous Holter monitoring may improve diagnostic yield compared with the st and ard of care including a 24-hour Holter recording . Methods — In the observational Find-AF trial ( IS RCT N 46104198 ) , consecutive patients presenting with symptoms of cerebral ischemia were included . Patients free from atrial fibrillation at presentation received  7-day Holter monitoring .  Results — Two hundred eighty-one patients were prospect ively included . Forty-four ( 15.7 % ) had atrial fibrillation documented by routine electrocardiogram on admission . All remaining patients received Holter monitors at a median of 5.5 hours after presentation . In those 224 patients who received Holter monitors but had no previously known paroxysmal atrial fibrillation , the detection rate with early and prolonged ( 7 days ) Holter monitoring  ( 12.5 % ) was significantly higher than for any 24-hour ( mean of 7 intervals : 4.8 % , P=0.015 ) or any 48-hour monitoring interval ( mean of 6 intervals : 6.4 % , P=0.023 ) . Of those 28 patients with new atrial fibrillation on Holter monitoring , 15 ( 6.7 % ) had been discharged without therapeutic anticoagulation after routine clinical care ( ie , with data from 24-hour Holter monitoring only ) . Detection rates were 43.8 % or 6.3 % for short supraventricular runs of ≥10 beats or prolonged episodes ( < 5 hours ) of atrial fibrillation , respectively . Diagnostic yield appeared to be only slightly and not significantly increased during the first 3 days after the index event . Conclusions — Prolongation of Holter monitoring in patients with symptoms of cerebral ischemic events increases the rate of detection of paroxysmal atrial fibrillation up to Day 7 , leading to a relevant change in therapy in a substantial number of patients . Early initiation of monitoring does not appear to be crucial . Hence , prolonged Holter monitoring ( ≥7 days ) should be considered for all patients with unexplained cerebral ischemia BACKGROUND AND PURPOSE A significant proportion of cryptogenic ischaemic strokes are due to paroxysmal atrial fibrillation ( AF ) . As paroxysmal AF appears to inexorably progress to persistent or permanent AF , this study with long-term follow-up was design ed to establish the profile of patients who developed AF after hospital discharge . METHODS All patients with cryptogenic ischaemic stroke over a 1-year period were included ( n = 164 ) . Patients were prospect ively followed up at the outpatient clinic . Information on long-term outcome included the presence of newly diagnosed AF ( NDAF ) . A specific NDAF assessment was performed at least 2 years after the index stroke using a structured telephone interview .  Baseline clinical , laboratory , and echocardiographic data of these patients were retrospectively recorded . Independent predictive factors were then used to produce a predictive grading score for NDAF , derived by logistic regression analysis . RESULTS With a median follow-up of 854 days , 22 cases of NDAF ( 13 % ) were observed . On multivariate analysis , factors associated with NDAF were age ≥72 years ( two points ) , history of coronary artery disease ( one point ) or stroke ( one point ) , and left atrial area ≥16 cm(2 ) ( two points ) ( total score ranging from 0 to 6 ) . Patients with a score ≤1 point did not have NDAF during follow-up . CONCLUSIONS In cryptogenic ischaemic stroke , the NDAF score can be used to target patients at high risk of developing AF after hospital discharge , as a score of 0 - 1 was highly predictive of the absence of NDAF during follow-up . These results need to be confirmed in prospect i ve studies BACKGROUND One quarter of strokes are of unknown cause , and sub clinical atrial fibrillation may be a common etiologic factor . Pacemakers can detect sub clinical episodes of rapid atrial rate , which correlate with electrocardiographically documented atrial fibrillation . We evaluated whether sub clinical episodes of rapid atrial rate detected by implanted devices were associated with an increased risk of ischemic stroke in patients who did not have other evidence of atrial fibrillation . METHODS We enrolled 2580 patients , 65 years of age or older , with hypertension and no history of atrial fibrillation , in whom a pacemaker or defibrillator had recently been implanted . We monitored the patients for 3 months to detect sub clinical atrial tachyarrhythmias ( episodes of atrial rate > 190 beats per minute for more than 6 minutes ) and followed them for a mean of 2.5 years for the primary outcome of ischemic stroke or systemic embolism .  Patients with pacemakers  were r and omly assigned to receive or not to receive continuous atrial overdrive pacing . RESULTS By 3 months , sub clinical atrial tachyarrhythmias detected by implanted devices had occurred in 261 patients ( 10.1 % ) . Sub clinical atrial tachyarrhythmias were associated with an increased risk of clinical atrial fibrillation ( hazard ratio , 5.56 ; 95 % confidence interval [ CI ] , 3.78 to 8.17 ; P<0.001 ) and of ischemic stroke or systemic embolism ( hazard ratio , 2.49 ; 95 % CI , 1.28 to 4.85 ; P=0.007 ) . Of 51 patients who had a primary outcome event , 11 had had sub clinical atrial tachyarrhythmias detected by 3 months , and none had had clinical atrial fibrillation by 3 months . The population attributable risk of stroke or systemic embolism associated with sub clinical atrial tachyarrhythmias was 13 % . Sub clinical atrial tachyarrhythmias remained predictive of the primary outcome after adjustment for predictors of stroke ( hazard ratio , 2.50 ; 95 % CI , 1.28 to 4.89 ; P=0.008 ) . Continuous atrial overdrive pacing did not prevent atrial fibrillation . CONCLUSIONS Sub clinical atrial tachyarrhythmias , without clinical atrial fibrillation , occurred frequently in patients with pacemakers and were associated with a significantly increased risk of ischemic stroke or systemic embolism . ( Funded by St. Jude Medical ; ASSERT Clinical Trials.gov number , NCT00256152 . ) BACKGROUND Atrial fibrillation ( AF ) , an important and treatable cause of ischaemic stroke , can occur as a sustained or a paroxysmal arrhythmia . Continuous cardiac rhythm monitoring ( Holter monitoring ) is often performed in stroke patients to identify paroxysmal AF , which is an indication for warfarin anti-coagulation in this patient population . AIM The aim of this study was to assess the clinical utility of Holter monitoring in detecting occult AF in patients with possible cardioembolic stroke . METHODS The medical records of ischaemic stroke patients consecutively hospitalized at a single academic centre during a one-year period were review ed . Data regarding patient demographics , stroke characteristics , electrocardiography and echocardiography results and duration and findings of Holter monitoring were abstract ed . The primary outcome was yield of newly diagnosed AF on Holter monitoring .  RESULTS Of 465 consecutive patients admitted with a diagnosis of new ischaemic stroke , 210 underwent Holter monitoring . The mean duration of monitoring was 22.8 + /- 4.0 h. Previously undiscovered AF was -identified in five cases ( 2.4 % ) , all of which represented non-rheumatic AF . In three cases , the Holter test was negative despite AF documented on an admission electro-cardiogram . CONCLUSIONS Holter monitoring can identify occult paroxysmal AF , assisting targeted secondary prevention in patients with new ischaemic stroke . However , the st and ard 24-h duration of monitoring probably under-estimates the prevalence of paroxysmal AF in this population . Prospect i ve studies are indicated to evaluate the value of longer monitoring periods in stroke population Background and Purpose — Pathophysiological considerations and observational studies indicate that elevated body temperature , hypoxia , hypotension , and cardiac arrhythmias in the acute phase of ischemic stroke may aggravate brain damage and worsen outcome . Methods — Both units were organized with the same st and ard care and multidisciplinary approach to nursing and rehabilitation . A blinded observer assessed functional outcome at 3 months with the modified Rankin scale ( mRS ) and Barthel Index ( BI ) . End points were ( 1 ) poor outcome , defined as either mRS ≥4 or BI < 60 or the need for institutional care and ( 2 ) mortality . Results — Fifty-four patients meeting the inclusion criteria were r and omized . The groups were well matched for baseline characteristics , stroke subtype , stroke severity , vascular risk factors , and prognostic factors . Poor outcome was seen in 7 ( 25.9 % ) patients in the SCMU group and in 13 ( 48.1 % ) in the SU group ( P = 0.16 ) . Mortality was lower in the SCMU group than in the SU group ( 1 [ 3.7 % ] vs 7 [ 25.9 % ] ; odds ratio , 0.11 [ 95 % CI , 0.02 to 0.96 ] , P = 0.05 ) . Conclusions — This pilot study suggests that admission of acute stroke patients to an SCMU may reduce mortality and poor outcome . A larger trial is required to confirm these findings Diagnosis of paroxysmal atrial fibrillation ( AF ) in stroke patients is challenging , but highly clinical ly relevant . The percentage of stroke patients with permanent AF  increases with age , but limited data are available for the age-dependent yield of paroxysmal AF by Holter monitoring . Patients with acute cerebral ischemia were included into the prospect i ve observational Find-AF study . Patients free from AF at presentation received 7 day Holter monitoring .  We calculated the percentage of otherwise undetected paroxysmal AF and the number needed to screen for age groups under 60 years , and in 5 year clusters from the age of 60 up to 85 and older . 272 patients were included , 43 ( 15.8 % ) had AF at admission , 33 patients with paroxysmal AF were identified by 7 day Holter ( n = 29 ) or medical history ( n = 4).The yield of 7 day Holter ECG  clearly increased with older age ( p = 0.004 ) : < 60 years : 5 % , 60–64 years : 5 % , 65–69 years : 7 % , 70–74 years : 11 % , 75–79 years : 13 % , 80–84 years : 25 % , ≥85 years : 39 % . The number needed to screen ( NNS ) to find one patient with paroxysmal AF decreased with age : ≤60 years : 18 , 60–64 years : 20 , 65–69 years : 14 , 70–74 years : 9 , 75–79 years : 8 , 80–84 years : 4 , ≥85 years : 3 , respectively . In patients < 65 years , all AF cases were detected by Holter ECG . The percentage of paroxysmal AF in stroke patients increases with age . The  7 day Holter ECG  is most efficient in elderly patients Background and Purpose — Patients with cryptogenic ischemic stroke may have undetected paroxysmal atrial fibrillation ( PAF ) . We established the Stroke and Monitoring for PAF in Real Time ( SMART ) Registry to determine the yield of 30-day outpatient PAF monitoring in cryptogenic ischemic stroke . Methods — The SMART Registry was a 3-year , prospect i ve multicenter registry of 239 patients with cryptogenic ischemic stroke undergoing 30-day outpatient autotriggered PAF detection in Kaiser Permanente Northern California . Results — In intention-to-monitor analysis , PAF was detected in 29 of 239 patients ( 12.1 % ; 95 % CI , 8.6%–16.9 % ) . After retrospective chart review was performed , a new diagnosis of PAF was confirmed in 26 of 236 patients ( 11.0 % ; 95 % CI , 7.6%–15.7 % ) . The majority of detected PAF events were asymptomatic ; only 6 of 98 recorded PAF events ( 6.1 % ) were patient-triggered or associated with symptoms . Conclusions — -Approximately 1 in every 9 patients with cryptogenic ischemic stroke was found to have new PAF within 30 days . Routine monitoring in this population should be strongly considered Purpose Ischemic stroke is a frequent pathology with high rate of recurrence and significant morbidity and mortality . There are several causes of stroke , affecting prognosis , outcomes , and management , but in many cases , the etiology remains undetermined . We hypothesized that atrial fibrillation was involved in this pathology but underdiagnosed by st and ard methods . The aim of the study was to determine the incidence of atrial fibrillation in cryptogenic ischemic stroke by using continuous monitoring of the heart rate over several months . The secondary objective was to test the value of atrial vulnerability assessment in predicting spontaneous atrial fibrillation . Methods and results We prospect ively enrolled 24 patients under 75 years of age , 15 men and 9 women of mean age 49 years , who within the last 4 months had experienced cryptogenic stroke diagnosed by clinical presentation and brain imaging and presumed to be of cardioembolic mechanism . All causes of stroke were excluded by normal 12-lead ECG , 24-h Holter monitoring , echocardiography , cervical Doppler , hematological , and inflammatory tests . All patients underwent electrophysiological study . Of the patients , 37.5 % had latent atrial vulnerability , and 33.3 % had inducible sustained arrhythmia . Patients were secondarily implanted with an implantable loop recorder to look for spontaneous atrial fibrillation over a mean follow-up interval of 14.5 months . No sustained arrhythmia was found . Only one patient had non-significant episodes of atrial fibrillation . Conclusion In this study , symptomatic atrial fibrillation or AF with fast ventricular rate has not been demonstrated by the implantable loop recorder  in patients under 75 years with unexplained cerebral ischemia . The use of this device should not be generalized in the systematic evaluation of these patients . In addition , this study attests that the assessment of atrial vulnerability is poor at predicting spontaneous arrhythmia in such patients Background and Purpose — Anticoagulation is a highly effective secondary prevention in patients with cardioembolic stroke and atrial fibrillation/flutter ( AF ) . However , the condition remains underdiagnosed , because paroxysmal AF may be missed by diagnostic tests in the acute phase . In this study , the sensitivity of AF detection was assessed for serial electrocardiographic recordings and continuous stroke unit telemetric monitoring with or without a structured algorithm to analyze telemetric data ( SEA-AF ) . Methods — Three hundred forty-six consecutive patients with acute ischemic stroke were prospect ively included and subjected to st and ard telemetric monitoring . In addition , telemetric data were separately analyzed following SEA-AF , consisting of a structured evaluation of episodes with high risk for AF and a chronological beat-to-beat screening of the full registration . Serial electrocardiograms  were conducted in 24-hour intervals . Results — Median effective telemetry monitoring time was 75.5 hours ( interquartile range 64–86 hours ) . Overall , AF was diagnosed in 119 of 346 patients ( 34.4 % ) . The structured reading algorithm was the most sensitive method to detected AF . Conventional telemetry and serial electrocardiographic assessment s were less effective . However , only 35 % of patients with previously documented paroxysmal AF and negative baseline electrocardiogram demonstrated AF episodes during monitoring . Conclusions — Continuous stroke unit telemetry using SEA-AF shows a significantly higher detection rate for AF compared with daily electrocardiographic assessment s and st and ard telemetry without structured reading . The low overall probability to detect paroxysmal AF with either method during the first days after stroke demonstrates the urgent need for complementary diagnostic strategies such as long-term monitoring and frequent follow-up assessment s. Clinical Trial Registration — URL : www . clinical trials.gov . Unique identifier : NCT01177748 The purpose of this study was to compare the diagnostic sensitivity of 1-day Holter monitoring versus 7-day Holter monitoring ( 7DH ) to detect atrial and ventricular arrhythmias in a population of stable patients with chronic heart failure and left ventricular dysfunction . Sixty-three consecutive stable patients with chronic heart failure with left ventricular ejection fractions < or = 50 % were included . Blood sample s were obtained , the Minnesota Living With Heart Failure Question naire was administered , and echocardiography , 6-minute walk tests , and 7DH were performed at enrollment . The mean ejection fraction was 35.8 + /- 9.8 % , and the mean age was 55.5 + /- 13.9 years .  Seven-day Holter monitoring did not significantly increase the detection of nonsustained atrial tachycardia or atrial fibrillation . In contrast , the incidence of nonsustained ventricular tachycardia increased in nonischemic patients from 35.1 % on day 1 to 54.1 % on day 7 ( p = 0.01 ) . In ischemic patients , the sensitivity increased from 11.5 % to 46.2 % ( p = 0.004 ) . Two patients without nonsustained ventricular tachycardia on day 1 had episodes of 13 and 16 beats on days 3 and 6 of monitoring . In patients with left ventricular ejection fractions > 35 % and N-terminal-pro-brain natriuretic peptide levels < 1,000 pg/ml , no episodes of nonsustained ventricular tachycardia were detected on day 1 in nonischemic and ischemic patients , but 7DH detected 3 new patients in each group . In conclusion , 7DH clearly improves the detection and allows a better characterization of ventricular arrhythmic episodes but seems to be less useful for supraventricular events BACKGROUND Atrial fibrillation is a leading preventable cause of recurrent stroke for which early detection and treatment are critical . However , paroxysmal atrial fibrillation is often asymptomatic and likely to go undetected and untreated in the routine care of patients with ischemic stroke or transient ischemic attack ( TIA ) . METHODS We r and omly assigned 572 patients 55 years of age or older , without known atrial fibrillation , who had had a cryptogenic ischemic stroke or TIA within the previous 6 months ( cause undetermined after st and ard tests , including 24-hour electrocardiography [ ECG ] ) , to undergo additional noninvasive ambulatory ECG monitoring with either a 30-day event-triggered recorder ( intervention group ) or a conventional 24-hour monitor ( control group ) . The primary outcome was newly detected atrial fibrillation lasting 30 seconds or longer within 90 days after r and omization . Secondary outcomes included episodes of atrial fibrillation lasting 2.5 minutes or longer and anticoagulation status at 90 days . RESULTS Atrial fibrillation lasting 30 seconds or longer was detected in 45 of 280 patients ( 16.1 % ) in the intervention group , as compared with 9 of 277 ( 3.2 % ) in the control group ( absolute difference , 12.9 percentage points ; 95 % confidence interval [ CI ] , 8.0 to 17.6 ; P<0.001 ; number needed to screen , 8) . Atrial fibrillation lasting 2.5 minutes or longer was present in 28 of 284 patients ( 9.9 % ) in the intervention group , as compared with 7 of 277 ( 2.5 % ) in the control group ( absolute difference , 7.4 percentage points ; 95 % CI , 3.4 to 11.3 ; P<0.001 ) . By 90 days , oral anticoagulant therapy had been prescribed for more patients in the intervention group than in the control group ( 52 of 280 patients [ 18.6 % ] vs. 31 of 279 [ 11.1 % ] ; absolute difference , 7.5 percentage points ; 95 % CI , 1.6 to 13.3 ; P=0.01 ) . CONCLUSIONS Among patients with a recent cryptogenic stroke or TIA who were 55 years of age or older , paroxysmal atrial fibrillation was common . Noninvasive ambulatory ECG monitoring for a target of 30 days significantly improved the detection of atrial fibrillation by a factor of more than five and nearly doubled the rate of anticoagulant treatment , as compared with the st and ard practice of short- duration ECG monitoring . ( Funded by the Canadian Stroke Network and others ; EMBRACE Clinical Trials.gov number , NCT00846924 . ) Background and Purpose — Atrial fibrillation ( AF ) elevates risk of recurrent stroke but is incompletely identified by st and ard investigation after stroke , though detection rates correlate with monitoring duration . We hypothesized that 7 days of noninvasive cardiac-event monitoring early after stroke would accelerate detection of AF and thus uptake of effective therapy . Methods — We performed a pragmatic r and omized trial with objective outcome assessment among patients presenting in sinus rhythm with no AF history , within 7 days of ischemic stroke symptom onset . Patients were r and omized to st and ard practice investigations ( SP ) to detect AF , or SP plus additional monitoring ( SP-AM ) . AM comprised 7 days of noninvasive cardiac-event monitoring reported by an accredited cardiac electrocardiology laboratory . Primary outcome was detection of AF at 14 days . Results — One-hundred patients were enrolled from 2 centers . Within 14 days of stroke , sustained paroxysms of AF were detected in 18 % of patients undergoing SP-AM versus 2 % undergoing SP ( P<0.05 ) . Paroxysms of any- duration were detected in 44 % of patients undergoing SP-AM versus 4 % undergoing SP ( P<0.001 ) . These differences persisted at 90 days . Anticoagulant therapy was commenced within 14 days in 16 % of SP-AM patients versus none r and omized to SP ( P<0.01 ) . This difference persisted to 90 days ( 22 % versus 6 % ; P<0.05 ) . Conclusions — Routine noninvasive cardiac-event monitoring after acute stroke enhances detection of paroxysmal AF and early anticoagulation . Extended monitoring should be offered to all eligible patients soon after acute stroke . Guidelines on investigation for AF in stroke patients could be strengthened . Clinical Trial Registration — URL : http://www.controlled-trials.com/is rct n/. Unique identifier : IS RCT N97412358 Background —Current methods for detecting atrial fibrillation ( AF ) have limited diagnostic yield . Continuous monitoring with automatic arrhythmia detection and classification may improve detection of symptomatic and asymptomatic AF and subsequent patient treatment . The study purpose was to quantify the performance of the first implantable leadless cardiac monitor ( ICM ) with dedicated AF detection capabilities . Methods and Results — Patients ( n=247 ) with an implanted ICM ( Reveal XT , Medtronic Inc , Minneapolis , Minn ) who were likely to present with paroxysmal AF were selected . A special Holter device stored 46 hours of subcutaneously recorded ECG , ICM markers , and 2 surface ECG leads . The ICM  automatic arrhythmia classification was compared with the core laboratory classification of the surface ECG . Of the 206 analyzable Holter recordings collected , 76 ( 37 % ) contained at least 1 episode of core laboratory classified AF . The sensitivity , specificity , positive predictive value , and negative predictive value for identifying patients with any AF were 96.1 % , 85.4 % , 79.3 % , and 97.4 % , respectively . The AF burden measured with the ICM was very well correlated with the reference value derived from the Holter ( Pearson coefficient=0.97 ) . The overall accuracy of the ICM for detecting AF was 98.5 % . Conclusions —In this ICM validation study , the dedicated AF detection algorithm reliably detected the presence or absence of AF and the AF burden was accurately quantified . The ICM is a promising new diagnostic and monitoring tool for the clinician to treat AF patients independently of symptoms . Long-term studies are needed to evaluate the clinical benefits of the technology . Clinical Trial Registration — clinical trials.gov Identifier NCT00680927 An ECG recording time of 24 hours has a low yield to detect atrial arrhythmias in patients after an acute ischemic stroke . The present study investigated whether a recording time of 72 instead of 24 hours detects paroxysmal atrial fibrillation in more patients . The study prospect ively included 82 consecutive patients 2 - 3 weeks after an acute ischemic stroke . All patients had sinus rhythm in the resting ECGs and no history of atrial fibrillation or flutter . The frequency of atrial fibrillation was assessed after 24 , 48 , and 72 hours of ambulatory ECG monitoring . An ECG monitoring time of 72 hours documented paroxysmal atrial fibrillation in five ( 6 % ) patients . The episode of paroxysmal atrial fibrillation occurred in only one patient within 24 hours . The other patients had their first episode of atrial fibrillation between 24 and 48 hours ( n = 2 ) and between 48 and 72 hours ( n = 2 ) . These five patients were older ( age = 70 + /- 5 years ) , whereas the mean age of the remaining patients was 59 + /- 13 years . All five patients had cardiovascular disease in comparison to 36 of 77 patients and reported palpitations in comparison to 6 of 77 of the remaining patients . In conclusion , ambulatory ECG monitoring over 72 hours detected after the first recording day four of five patients in whom paroxysmal atrial fibrillation could be documented for the first time . The 72-hour recording time improved , compared to the 24-hour period , the detection of paroxysmal atrial fibrillation in patients after an ischemic stroke . It seems to be more efficient to perform prolonged ECG recording mainly in older patients with a cardiovascular disease and /or a history of palpitations BACKGROUND It is unclear if brief episodes of paroxysmal atrial fibrillation ( PAF ) detected by prolonged cardiac monitoring are an occult of cause of cryptogenic strokes ( CS ) . We compared the incidence of PAF in patients with CS and patients with stroke of known cause ( SKC ) using prolonged ambulatory cardiac monitoring . METHODS We prospect ively enrolled patients within 3 months of ischemic stroke to undergo noninvasive cardiac monitoring for 3 weeks . Primary end point was PAF detection independently confirmed by 2 blinded cardiologists . RESULTS The study consisted of 132 patients , 66 had CS and 66 had SKC .  Episodes of PAF were detected in 16 of 64 ( 25 % ) patients with CS and 9 of 64 ( 14 % ) patients with SKC ( P=.12 ) . Duration and number of PAF episodes , PAF burden , and time of first PAF detection did not differ significantly between the 2 groups ( P>.05 for all ) . In patients younger than 65 years , PAF was more common in the CS group ( 22 % versus 3 % ; P=.07 ) , whereas in patients 65 years or older , the rates of detection were similar ( 27 % in CS versus 25 % in SKC ; P=.9 ) . Among patients younger than 65 years with embolic imaging pattern , PAF was only observed in the CS group ( 21 % versus 0 % ; P=.03 ) . CONCLUSIONS Very short episodes of PAF are common in patients with CS and with SKC , but their pathogenic significance is unclear . Predominance of PAF in younger patients with CS and embolic infa rct pattern suggests a causative role in these cases . More research is needed before prolonged cardiac rhythm monitoring can be recommended to guide anticoagulation in CS patients Background and Purpose — Observational studies indicate that outpatient cardiac monitoring detects previously undiagnosed atrial fibrillation ( AF ) in 5 % to 20 % of patients with recent stroke . However , it remains unknown whether the yield of monitoring exceeds that of routine clinical follow-up . Methods — In a pilot trial , we r and omly assigned 40 patients with cryptogenic ischemic stroke or high-risk transient ischemic attack to wear a Cardionet mobile cardiac outpatient telemetry monitor for 21 days or to receive routine follow-up alone . After thorough investigation , we excluded patients with documented AF or other apparent stroke pathogenesis . We contacted patients and their physicians at 3 months and at 1 year to ascertain any diagnoses of AF or recurrent stroke or transient ischemic attack . Results — The baseline characteristics of our cohort broadly matched those of previous observational studies of monitoring after stroke . In the monitoring group , patients wore monitors for 64 % of the assigned days , and 25 % of patients were not compliant at all with monitoring . No patient in either study arm received a diagnosis of AF . Cardiac monitoring revealed AF in zero patients ( 0 % ; 95 % confidence interval , 0%–17 % ) , brief episodes of atrial tachycardia in 2 patients ( 10 % ; 95 % confidence interval , 1%–32 % ) , and nonsustained ventricular tachycardia in 2 patients ( 10 % ; 95 % confidence interval , 1%–32 % ) . Conclusions — In the first reported r and omized trial of cardiac monitoring after cryptogenic stroke , the rate of AF detection was lower than expected , incidental arrhythmias were frequent , and compliance with monitoring was suboptimal . Our findings highlight the challenges of prospect ively identifying stroke patients at risk for harboring paroxysmal AF and ensuring adequate compliance with cardiac monitoring . Clinical Trial Registration — URL : http:// clinical trials.gov . Unique Identifier : BACKGROUND AND PURPOSE Detection of atrial fibrillation is of vital importance because oral anticoagulation decreases the risk of a stroke by 64 % . Current st and ards for stroke unit treatment require continuous electrocardiogram ( ECG ) monitoring for at least 24 h. Additionally , a 24-h HOLTER ECG ( HOLTER ) should be performed in selected patients . It remains unclear whether continuous monitoring at the bedside is equivalent to HOLTER for the detection of atrial fibrillation . Furthermore , we investigate how many additional patients with paroxysmal atrial fibrillation can be identified as a result of a longer duration of continuous monitoring . METHODS In this study , we prospect ively compared the detection rates of HOLTER and 24-h monitoring at the Stroke Unit at the University of Heidelberg over a period of 9 months . Continuous monitoring was analyzed by trained nurses , HOLTER by cardiologists . RESULTS We included 370 patients with ischemic stroke or transient ischemic attack ( TIA ) in our study . Of these , 192 patients underwent HOLTER . Previously unknown atrial fibrillation was detected in 44 patients , 13 patients had no atrial fibrillation in baseline ECG , but  atrial fibrillation  was detected by continuous monitoring . In two patients , the HOLTER showed atrial fibrillation ; both patients had also been detected by continuous monitoring . Median time to detection of the atrial fibrillation during continuous monitoring was 43 h after hospitalization . CONCLUSION In this study , use of HOLTER does not give any additional benefit in comparison with continuous monitoring with intermittent analysis by trained staff alone . The median detection time of 43 h emphasizes the importance of longer continuous monitoring BACKGROUND Several studies have suggested that after ischemic stroke , continuous electrocardiographic ( ECG ) monitoring ( CEM ) increases the atrial fibrillation ( AF ) detection rate . However , optimal CEM terms of use are not clear . The aim of our study was to evaluate the usefulness of CEM in detecting AF and define optimal terms of the use of CEM . METHODS We prospect ively enrolled consecutive patients with acute ischemic stroke who were admitted to the stroke unit without AF on baseline ECG . We compared 2 strategies of AF detection : the first using CEM and the second with routine clinical practice ( 24-hour Holter ECG and additional ECGs ) . Adjusted odds ratios for the association between AF diagnosis and the use of CEM stratified by monitoring duration were calculated using multivariate logistic regression analysis . RESULTS Of the 1166 patients included , 220 ( 18.87 % ) had AF on baseline ECG and were excluded . Of the 946 remaining patients , 592 underwent CEM . The prevalence of AF using CEM  was 12.50 % compared 2.26 % using the routine strategy . After adjustment ( demographic data , vascular risk factors , and National Institutes of Health Stroke Scale scores ) , using CEM increased 5.29 fold the odds of finding AF ( 95 % confidence interval [ CI ] 2.43 - 11.55 ) compared to the routine strategy . The adjusted odds ratio ( 9.82 ; 95 % CI 3.01 - 32.07 ) was maximum for the first day of monitoring and decreased later . Beyond 5 days ,  CEM usefulness was not significantly higher than the routine strategy . CONCLUSIONS We suggest that in order to enhance the detection rate of AF , CEM could be generalized in the stroke unit . It must be started early in patients with acute stroke and prolonged over a minimum of 4 days UNLABELLED Detection of paroxysmal atrial fibrillation ( PAF ) in patients with recent ischemic stroke or TIA suggests a cardioembolic etiology and leads to initiation of oral anticoagulation in suitable c and i date s. We assessed the diagnostic and therapeutic impact of adding ambulatory electrocardiography ( 24 hr ECG ) to a st and ardised ischemic stroke workup . METHODS We measured the frequency of detection of PAF in consecutive stroke patients who underwent 24 hr ECG that was not diagnosed clinical ly or on a st and ard 12-lead ECG .  RESULTS One hundred forty five ischemic stroke patients were included . 24 hr  ECG  was obtained in 136 patients ( 93.8 % ) . Clinical ly unsuspected PAF was detected on 24 hr ECG in 7 patients ( 5.1 % ) . The secondary prevention measure changed from antiplatelet agents to oral anticoagulation in 6 of 7 patients . CONCLUSION Our findings suggest that  ambulatory electrocardiography  is a valuable diagnostic tool in the workup of stroke patients . Further prospect i ve studies are needed to identify , subtypes of patients in whom the yield of  ambulatory electrocardiography  is higher Atrial fibrillation ( AF ) is intermittent in 30 % of patients with cardioembolic stroke and , therefore , might not be seen in a single st and ard ECG recording . The aim of this study was to evaluate if prolonged ECG monitoring ( 96 h ) finds episodes of intermittent AF beyond the 24 h ECG monitoring in patients with cryptogenic stroke or transient ischemic attack ( TIA ) . We prospect ively evaluated consecutive patients affected by cryptogenic stroke or TIA who had sinus rhythm on a 12-lead ECG on admission , and during ECG monitoring performed in the acute phase ( for at least 24 h ) . Patients had continuous 96 h Holter ECG monitoring within 30 days from stroke onset . 114 patients were included in the study ( mean age 63.1 ± 15.1 , 59 males ) .  AF was found in 29 patients ( 24.3 % ) . In 20 patients , AF was found in the first 24 h of recording , and in nine patients after 24 h. In addition , several other dysrhythmias such as supraventricular ectopic activity ( 33 ) , ventricular tachycardia ( 10 ) , sinus pause ( 4 ) and sinus-atrial block ( 1 ) were found . In patients with cryptogenic stroke or TIA , 96 h ECG monitoring detected a high rate of AF . One-third of AF was seen beyond 24 h of ECG monitoring BACKGROUND Studies about continuous electrocardiographic ( ECG ) monitoring in detection of paroxysmal atrial fibrillation ( PAF ) in Asian patients with acute ischemic stroke are very limited . We looked for the prevalence and associated factors of atrial fibrillation ( AF ) and PAF in Thai patients with acute ischemic stroke . METHODS In all , 204 patients with acute ischemic stroke were prospect ively included .  Snapshot 12-lead ECG and continuous ECG monitoring for at least the first 24 hours were performed . Multivariate analyses were performed to find out the associated factors of AF and PAF . RESULTS AF was diagnosed in 31 patients ( 15 % ) and PAF in 15 patients ( 7 % ) . Twelve and 3 patients with PAF were diagnosed by continuous ECG monitoring and snapshot 12-lead ECG , respectively . Mean duration of continuous ECG monitoring and mean time to detect PAF were 55 and 23 hours , respectively . Multivariate analysis revealed that age of 70 years or older ( odds ratio [ OR ] 3.52 , 95 % confidence interval [ CI ] 1.68 - 7.35 , P = .001 ) and heart diseases ( OR 4.26 , 95 % CI 1.14 - 15.95 , P = .031 ) were associated with AF and PAF . CONCLUSIONS AF/PAF was one of the common causes of ischemic stroke in Thai patients . Most PAF was detected by continuous ECG monitoring . Snapshot 12-lead ECG and continuous ECG monitoring should be recommended in all patients with acute ischemic stroke BACKGROUND Patients with atrial fibrillation ( AF ) are at increased risk for ischemic stroke . In patients who have suffered a stroke , screening for AF is routinely performed only for a short period after the stroke as part of the evaluation for possible causes . If AF is detected after an ischemic stroke , oral anticoagulation therapy is recommended for secondary stroke prevention . In 25 % to 30 % of stroke patients , the stroke mechanism can not be determined ( cryptogenic stroke ) . The incidence of paroxysmal AF undetected by short-term monitoring in patients with cryptogenic stroke is unknown , but has important therapeutic implication s on patient care . The optimum monitoring duration and method of AF detection after stroke are unknown . The purpose of this study is to evaluate the incidence of AF and time to AF detection in patients with cryptogenic stroke using an insertable cardiac monitor . STUDY DESIGN The CRYSTAL AF trial is a r and omized prospect i ve study to evaluate a novel approach to long-term monitoring for AF detection in patients with cryptogenic stroke . Four hundred fifty cryptogenic stroke patients ( by definition , without a history of AF ) will be enrolled at approximately 50 sites in Europe , Canada , and the United States . Patients will be r and omized in a 1:1 fashion to st and ard arrhythmia monitoring ( control arm ) or implantation of the subcutaneous cardiac monitor ( Reveal XT ; Medtronic , Inc , Minneapolis , MN ) ( continuous monitoring arm ) . OUTCOMES The primary end point is time to detection of AF within 6 months after stroke . The clinical follow-up period will be at least 12 months . Study completion is expected at the end of 2012 Atrial fibrillation and atrial flutter are common cardiac arrhythmias associated with an increased risk of stroke in patients with additional risk factors .  Anticoagulation ameliorates stroke risk , but because these arrhythmias may occur intermittently without symptoms , initiation of prophylactic therapy is often delayed until electrocardiographic documentation is obtained . The IMPACT study is a multicenter , r and omized trial of remote surveillance technology in patients with implanted dual-chamber cardiac resynchronization therapy defibrillator ( CRT-D ) devices design ed to test the hypothesis that initiation and withdrawal of oral anticoagulant therapy guided by continuous ambulatory monitoring of the atrial electrogram improve clinical outcomes by reducing the combined rate of stroke , systemic embolism , and major bleeding compared with conventional clinical management . For those in the intervention group , early detection of atrial high-rate episodes ( AHRE ) generates an automatic alert to initiate anticoagulation based on patient-specific stroke risk stratification . Subsequently , freedom from AHRE for predefined periods prompts withdrawal of anticoagulation to avoid bleeding . Patients in the control arm are managed conventionally , the anticoagulation decision prompted by incidental detection of atrial fibrillation or atrial flutter during routine clinical follow-up . The results will help define the clinical utility of wireless remote cardiac rhythm surveillance and help establish the critical threshold of AHRE burden warranting anticoagulant therapy in patients at risk of stroke . In this report , we describe the study design and baseline demographic and clinical features of the initial cohort ( 227 patients ) Background : Atrial fibrillation ( AF ) is a frequent cause of stroke , but detecting paroxysmal AF ( pAF ) poses a challenge . We investigated whether continuous bedside ECG monitoring in a stroke unit detects pAF more sensitively than 24-hour Holter ECG , and tested whether examining RR interval dynamics on short-term ECG recordings using an automated screening algorithm ( ASA ) for pAF detection is a useful tool to predict the risk of pAF outside periods of manifest AF . Methods : Patients > 60 years with acute ischemic stroke or transient ischemic attacks ( TIA ) were prospect ively enrolled unless initial ECG revealed AF or they had a history of paroxysmal or persistent AF . ASA was performed on 1- to 2-hour ECG recordings in the emergency room and patients were classified into 5 risk categories for pAF . All patients underwent continuous bedside ECG monitoring for > 48 h. Additionally , 24-hour Holter ECG was performed . Results : 136 patients were enrolled ( median age : 72 years , male : 58.8 % ) . In 29 ( 21.3 % ) , pAF was newly diagnosed by continuous bedside ECG monitoring . pAF increased with age ( p = 0.031 ) . Median time to first pAF detection on continuous bedside ECG monitoring was 36 h. In 16 patients , pAF was detected by continuous bedside ECG monitoring prior to the performance of 24-hour Holter ECG . Thirteen of the remaining patients were pAF positive on continuous bedside ECG monitoring , but 24-hour Holter detected only 3 patients . Accordingly , the sensitivity of 24-hour Holter was 0.23 . Sensitivity of higher-risk categories of ASA compared to continuous bedside ECG monitoring was 0.72 , and specificity 0.63 . Conclusion : Continuous bedside ECG monitoring is more sensitive than 24-hour Holter ECG for pAF detection in acute stroke/TIA patients . Screening patients for pAF outside AF episodes using ASA requires further development This pilot study in a prospect i ve cohort of 20 cryptogenic stroke patients showed that a significant proportion has paroxysmal atrial fibrillation undetected by 24-h Holter monitoring . However , longer monitoring with 28-day Holter was poorly tolerated and still insufficiently sensitive for paroxysmal atrial fibrillation detection . Further studies are urgently needed to eluci date the optimal timing , method and duration of cardiac rhythm monitoring following ischaemic stroke Atrial fibrillation ( AF ) and paroxysmal AF ( PAF ) are common causes of stroke which may not be detected by a single electrocardiogram ( EKG ) . We conducted a prospect i ve study to determine if 48 hours of telemetry monitoring increased the rate of detection of AF in patients with acute stroke and thus identified patients requiring anticoagulation . One hundred and fifty consecutive patients with acute ischemic stroke were placed on telemetry monitoring for 48 hours . Thirty-five patients had AF related strokes . There were 12 patients with AF related stroke who did not have a previous history of AF and were found to have AF following the stroke . Six of these 12 patients were found to have AF on their admission EKG . The remaining six patients had normal admission EKGs and were diagnosed with AF only during telemetry monitoring for 48 hrs . Patients with AF were older , had larger strokes , which were more likely to be non-lacunar , than patients without AF . Our study suggests that AF is sometimes undiagnosed until a stroke occurs . Improved methods of detection of AF are needed in high-risk patients for primary stroke prevention . Patients older than 65 years of age with non-lacunar strokes should have 48 hours of telemetry monitoring to detect previously undiagnosed AF BACKGROUND Current guidelines recommend at least 24 hours of electrocardiographic ( ECG ) monitoring after an ischemic stroke to rule out atrial fibrillation . However , the most effective duration and type of monitoring have not been established , and the cause of ischemic stroke remains uncertain despite a complete diagnostic evaluation in 20 to 40 % of cases ( cryptogenic stroke ) . Detection of atrial fibrillation after cryptogenic stroke has therapeutic implication s. METHODS We conducted a r and omized , controlled study of 441 patients to assess whether long-term monitoring with an insertable cardiac monitor ( ICM ) is more effective than conventional follow-up ( control ) for detecting atrial fibrillation in patients with cryptogenic stroke . Patients 40 years of age or older with no evidence of atrial fibrillation during at least 24 hours of ECG monitoring  underwent r and omization within 90 days after the index event . The primary end point was the time to first detection of atrial fibrillation ( lasting > 30 seconds ) within 6 months . Among the secondary end points was the time to first detection of atrial fibrillation within 12 months . Data were analyzed according to the intention-to-treat principle . RESULTS By 6 months , atrial fibrillation had been detected in 8.9 % of patients in the ICM group ( 19 patients ) versus 1.4 % of patients in the control group ( 3 patients ) ( hazard ratio , 6.4 ; 95 % confidence interval [ CI ] , 1.9 to 21.7 ; P<0.001 ) . By 12 months , atrial fibrillation had been detected in 12.4 % of patients in the ICM group ( 29 patients ) versus 2.0 % of patients in the control group ( 4 patients ) ( hazard ratio , 7.3 ; 95 % CI , 2.6 to 20.8 ; P<0.001 ) . CONCLUSIONS ECG monitoring with an ICM was superior to conventional follow-up for detecting atrial fibrillation after cryptogenic stroke . ( Funded by Medtronic ; CRYSTAL AF Clinical Trials.gov number , NCT00924638 . ) Background : Paroxysmal atrial fibrillation ( PAF ) may remain underdiagnosed after stroke , as suggested by long- duration EKG monitoring . Here we report the sensitivity of transtelephonic EKG monitoring ( TTM ) for detection of PAF in patients following a recent stroke or TIA and a negative 24-hour Holter . Methods : We analyzed data from 98 consecutive patients with TTM and noncardioembolic TOAST stroke ( n = 78 ) or TIA ( n = 20 ) . Most were cryptogenic events ( 82 % ) . Patients started TTM 0.8 months ( interquartile range 0.4–2.5 ) after the indexed event and r and omly recorded about 1 EKG per day for 1 month . Univariate and multivariate analyses were run to identify PAF predictors . Results : Seventeen PAF episodes were detected in 9.2 % ( 9/98 ) of the patients . The estimated duration of PAF episodes ranged from 4 to 72 hours . Two predictors were identified : premature atrial ectopic beats ( more than 100 ) in 24-hour routine Holter ( odds ratio [ OR ] = 11.0 ; 95 % confidence interval [ CI ] 1.9–62 ; p = 0.007 ) and nonlacunar anterior circulation DWI hypersignals ( OR = 9.9 ; 95 % CI 1.1–90.6 ; p = 0.04 ) . The PAF detection rate varied from 42.6 % for patients meeting both criteria to 0 % for patients with neither of them . Conclusions : Transtelephonic EKG monitoring increases detection rate of paroxysmal atrial fibrillation in stroke and TIA patients whose 24-hour Holter result was negative , especially if they had frequent premature atrial ectopic beats , recent anterior circulation infa rct on MRI , or both
target: Longer duration of electrocardiographic monitoring after cryptogenic stroke is associated with a greater detection of AF .
background: BACKGROUND Atrial fibrillation ( AF ) is a major cause of stroke .
  Although st and ard investigations after an event include electrocardiographic monitoring , the optimal duration to detect AF is unclear .
  We performed a systematic review and meta- analysis to determine whether the duration of electrocardiographic monitoring after an ischemic event is related to the detection of AF .