title: Long-term follow-up of patients from a randomised trial of atrial versus ventricular pacing for sick-sinus syndrome Atrial High Rate Episodes Detected by Pacemaker Diagnostics Predict Death and Stroke: Report of the Atrial Diagnostics Ancillary Study of the MOde Selection Trial (MOST) Randomized Trial of Atorvastatin for Reduction of Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery: Results of the ARMYDA-3 (Atorvastatin for Reduction of MYocardial Dysrhythmia After cardiac surgery) Study Atorvastatin prevents atrial fibrillation in patients with bradyarrhythmias and implantation of an atrial-based or dual-chamber pacemaker: a prospective randomized trial. Ventricular pacing or dual-chamber pacing for sinus-node dysfunction. Asymptomatic atrial fibrillation in pacemaker recipients: incidence, progression, and determinants based on the atrial high rate trial. The HMG-CoA reductase inhibitor atorvastatin prevents atrial fibrillation by inhibiting inflammation in a canine sterile pericarditis model. Minimizing ventricular pacing to reduce atrial fibrillation in sinus-node disease. A randomized comparison of atrial and dual-chamber pacing in 177 consecutive patients with sick sinus syndrome: echocardiographic and clinical outcome. Randomized pilot study of a new atrial-based minimal ventricular pacing mode in dual-chamber implantable cardioverter-defibrillators. Atrial fibrillation after DDDR pacemaker implantation. The acute effect of cardiac pacing mode on endothelial vasodilation: prospective, double-blind, cross-over, comparative clinical study. The −174G/C Interleukin-6 Polymorphism Influences Postoperative Interleukin-6 Levels and Postoperative Atrial Fibrillation. Is Atrial Fibrillation an Inflammatory Complication? Diagnosis of paroxysmal atrial fibrillation in patients with implanted pacemakers: relationship to symptoms and other variables. Long-term risk of recurrent atrial fibrillation as documented by an implantable monitoring device: implications for optimal patient care. Usefulness of statin drugs in protecting against atrial fibrillation in patients with coronary artery disease.
abstract: BACKGROUND In a previous study of 225 patients with sick-sinus syndrome r and omised to either single-chamber atrial pacing ( n=110 ) or single-chamber ventricular pacing ( n=115 ) , we found that after a mean follow-up of 3.3 years , atrial pacing was associated with significantly less atrial fibrillation and thromboembolism whereas there was no significant difference in mortality and heart failure between the two groups . We aim ed to find out whether this beneficial effect of atrial pacing is maintained during extended follow-up of up to 8 years . METHODS Follow-up visits for all patients were at 3 months , 12 months , then once a year at which patients had a physical examination , ECG recording , and pacemaker check-up . Endpoints were mortality , cardiovascular death , atrial fibrillation , thromboembolic events , heart failure , and atrioventricular block . Data was analysed on Dec 31 , 1996 . FINDINGS At long-term follow-up , 39 patients from the atrial group had died versus 57 from the ventricular group ( relative risk 0.66 [ 95 % CI 0.44 - 0.99 ] ; p=0.045 ) . 19 patients from the atrial group and 39 patients from the ventricular group died from a cardiovascular cause ( 0.47 [ 0.27 - 0.82 ] ; p=0.0065 ) . The cumulative incidences of atrial fibrillation and chronic atrial fibrillation were also significantly lower in the atrial group than in the ventricular group ( 0.54 [ 0.33 - 0.89 ] , p=0.012 and 0.35 [ 0.16 - 0.76 ] , p=0.004 , respectively ) . Thromboembolic events occurred in 13 patients in the atrial group and 26 in the ventricular group ( 0.47 [ 0.24 - 0.92 ] , p=0.023 ) . Heart failure was less severe in the atrial group than in the ventricular group ( p<0.05 ) . In multivariate analysis , atrial pacing was significantly associated with freedom from thromboembolic events ( 0.47 [ 0.24 - 0.92 ] , p=0.028 ) and survival from cardiovascular death ( 0.52 [ 0.30 - 0.91 ] , p=0.022 ) , but no longer with overall survival ( 0.71 [ 0.46 - 1.08 ] , p=0.11 ) or chronic atrial fibrillation ( 0.45 [ 0.20 - 1.05 ] , p=0.063 ) . Atrioventricular block occurred in four patients in the atrial group ( 0.6 % annual risk ) . INTERPRETATION The beneficial effect of atrial pacing found in our previous study is enhanced substantially over time . Patients with sick-sinus syndrome should be treated with an atrial rather than ventricular-pacing system because after long-term follow-up , atrial pacing is associated with a significantly higher survival , less atrial fibrillation , fewer thromboembolic complications , less heart failure , and a low-risk of atrioventricular block Background —Some current pacing systems can automatically detect and record atrial tachyarrhythmias that may be asymptomatic . We prospect ively studied a 312-patient ( pt ) subgroup of MOST ( MOde Selection Trial ) , a 2010-patient , 6-year r and omized trial of DDDR versus VVIR pacing in sinus node dysfunction ( SND ) . The purpose of the study was to correlate atrial high rate events ( AHREs ) detected by pacemaker diagnostics with clinical outcomes . Methods and Results —Pacemakers were programmed to log an AHRE when the atrial rate was > 220 bpm for 10 consecutive beats . Analysis was confined to patients with at least 1 AHRE duration exceeding 5 minutes . The 312 patients were median age 74 years , 55 % female , and 60 % had a history of SVT . 160 of 312 ( 51.3 % ) patients enrolled had at least 1 AHRE > 5 minutes duration over median follow-up of 27 months . Cox proportional hazards analysis assessed the relationship of AHREs with clinical events , adjusting for prognostic variables and baseline covariates . The presence of any AHRE was an independent predictor of the following : total mortality ( hazard ratio AHRE versus no AHRE and 95 % confidence intervals=2.48 [ 1.25 , 4.91 ] , P = 0.0092 ) ; death or nonfatal stroke ( 2.79 [ 1.51 , 5.15 ] , P = 0.0011 ) ; and atrial fibrillation ( 5.93 [ 2.88 , 12.2 ] , P = 0.0001 ) . There was no significant effect of pacing mode on the presence or absence of AHREs . Conclusions —AHRE detected by pacemakers in patients with SND identify patients that are more than twice as likely to die or have a stroke , and 6 times as likely to develop atrial fibrillation as similar patients without AHRE Background — Atrial fibrillation ( AF ) after cardiac surgery is associated with increased risk of complications , length of stay , and cost of care . Observational evidence suggests that patients who have undergone previous statin therapy have a lower incidence of postoperative AF . We tested this observation in a r and omized , controlled trial . Methods and Results — Two hundred patients undergoing elective cardiac surgery with cardiopulmonary bypass , without previous statin treatment or history of AF , were enrolled . Patients were r and omized to atorvastatin ( 40 mg/d , n=101 ) or placebo  ( n=99 ) starting 7 days before operation . The primary end point was incidence of postoperative AF ; secondary end points were length of stay , 30-day major adverse cardiac and cerebrovascular events , and postoperative C-reactive protein ( CRP ) variations . Atorvastatin significantly reduced the incidence of AF versus placebo ( 35 % versus 57 % , P=0.003 ) . Accordingly , length of stay was longer in the placebo versus atorvastatin arm ( 6.9±1.4 versus 6.3±1.2 days , P=0.001 ) . Peak CRP levels were lower in patients without AF ( P=0.01 ) , irrespective of r and omization assignment . Multivariable analysis showed that atorvastatin treatment conferred a 61 % reduction in risk of AF ( odds ratio 0.39 , 95 % confidence interval 0.18 to 0.85 , P=0.017 ) , whereas high postoperative CRP levels were associated with increased risk ( odds ratio 2.0 , 95 % confidence interval 1.2 to 7.0 , P=0.01 ) . The incidence of major adverse cardiac and cerebrovascular events at 30 days was similar in the 2 arms . Conclusions — Treatment with atorvastatin 40 mg/d , initiated 7 days before surgery , significantly reduces the incidence of postoperative AF after elective cardiac surgery with cardiopulmonary bypass and shortens hospital stay . These results may influence practice patterns with regard to adjuvant pharmacological therapy before cardiac surgery BACKGROUND Increasing evidence suggests that atrial fibrillation ( AF ) is an inflammatory disease . Statins is an anti-inflammatory agent . The present study was conducted to test the efficacy of atorvastatin in preventing paroxysmal AF or atrial high rate episodes ( AHEs ) in patients with bradyarrhythmias and implantation of an atrial-based or dual-chamber pacemaker . METHODS The effect of atorvastatin on time to the first attack of AF or AHE ( > or = 180 per minute and > or = 1 or 10 minutes ) , which was accurately detected by pacemaker interrogation , was evaluated in an open-label prospect i ve r and omized design for 1 year of follow-up . RESULTS Fifty-two patients ( 23 males , 70 + /- 13 years old ) were r and omized to the  statin group ( atorvastatin 20 mg/d ) and 54 ( 25 males , 72 + /- 13 years old ) to the  nonstatin group . Event-free survivals from AHE > or = 1 minute were not significantly different between the 2 groups ( log-rank P = .410 ) . However , patients in the nonstatin group were more likely to develop AHE > or = 10 minutes than those in the statin group ( log-rank P = .028 ) . Atrial high rate episode > or = 10 minutes occurred in 3 ( 5.8 % ) of 51 patients in the statin group after 1 year of follow-up , and 10 ( 19.2 % ) of 52 patients ( odds ratio 0.26 , P = .041 ) in the nonstatin group . The mean left atrial volume of the statin group was significantly lower than that of the nonstatin group at the end of follow-up ( 39.7 + /- 1.7 vs 43.7 + /- 1.9 mL , P < .0001 ) . CONCLUSIONS The present study demonstrated the efficacy of atorvastatin in preventing significant AF ( > or = 10 minutes ) and left atrial enlargement in patients with bradyarrhythmias and implantation of a pacemaker BACKGROUND Dual-chamber ( atrioventricular ) and single-chamber ( ventricular ) pacing are alternative treatment approaches for sinus-node dysfunction that causes clinical ly significant bradycardia . However , it is unknown which type of pacing results in the better outcome . METHODS We r and omly assigned a total of 2010 patients with sinus-node dysfunction to dual-chamber pacing ( 1014 patients ) or ventricular pacing ( 996 patients ) and followed them for a median of 33.1 months . The primary end point was death from any cause or nonfatal stroke . Secondary end points included the composite of death , stroke , or hospitalization for heart failure ; atrial fibrillation ; heart-failure score ; the pacemaker syndrome ; and the quality of life . RESULTS The incidence of the primary end point did not differ significantly between the dual-chamber group ( 21.5 percent ) and the ventricular-paced group ( 23.0 percent , P=0.48 ) . In patients assigned to dual-chamber pacing , the risk of atrial fibrillation was lower ( hazard ratio , 0.79 ; 95 percent confidence interval , 0.66 to 0.94 ; P=0.008 ) , and heart-failure scores were better ( P<0.001 ) . The differences in the rates of hospitalization for heart failure and of death , stroke , or hospitalization for heart failure were not significant in unadjusted analyses but became marginally significant in adjusted analyses . Dual-chamber pacing result ed in a small but measurable increase in the quality of life , as compared with ventricular pacing . CONCLUSIONS In sinus-node dysfunction , dual-chamber pacing does not improve stroke-free survival , as compared with ventricular pacing . However , dual-chamber pacing reduces the risk of atrial fibrillation , reduces signs and symptoms of heart failure , and slightly improves the quality of life . Overall , dual-chamber pacing offers significant improvement as compared with ventricular pacing BACKGROUND The epidemiology and clinical implication s of asymptomatic atrial tachyarrhythmias ( AT ) including both atrial fibrillation and flutter in pacemaker recipients with and without arrhythmia history are not well understood . The Atrial High Rate Episodes ( A-HIRATE ) in Pacemaker Patients Trial was design ed to identify and compare the incidence of AT in patients with and without previously diagnosed AT and a st and ard indication for dual chamber pacing  , and to provide useful diagnostic information for clinical management . METHODS Four hundred twenty-seven patients were implanted with a pacemaker ( Kappa 7 - 900 , Medtronic , Inc. , Minneapolis , MN , USA ) capable of detecting and storing multiple atrial high rate episodes ( AHRE ) and followed for 2 years . Group I included 331 patients without prior history of AT and Group II included 96 patients with prior AT history . RESULTS Pacemaker diagnostics appropriately detected 93 % of review ed AHRE . The rate of occurrence of first AHRE was significantly higher ( P < 0.0001 ) in Group II patients , as was average AHRE burden . The rate of first AHRE occurrence was 88.6 % for patients in Group II and 53.8 % in Group I at 24 months post-implant . The rate of AHRE occurrence was similar in both groups after the first month post-implant . The majority of stored AHRE were asymptomatic ; symptoms did not correspond to an actual AHRE in most patients . CONCLUSIONS The incidence of AT in pacemaker recipients is high . Most device-detected AHRE are asymptomatic . Prior history of AT is associated with higher arrhythmia burden . AHRE diagnostics have a high positive predictive value for identifying AT events OBJECTIVE It has been recently reported that AF is associated with tissue inflammation . Statins reduce C-reactive protein ( CRP ) levels . However , the effect of statin on atrial fibrillation ( AF ) is unclear . The purpose of the present study was to evaluate the effect of statin on AF in a canine sterile pericarditis model . METHODS Sterile pericarditis was created in 20 dogs r and omly assigned to two groups : a control group ( 10 dogs ) and an atorvastatin treatment group ( 10 dogs ) . Atorvastatin was administered orally ( 2 mg/kg/day ) beginning 1 week before the operation until the end of the study . Before and 2 days after the operation , CRP levels , the duration of induced AF , the atrial effective refractory period ( AERP ) , and intra-atrial conduction time were determined . RESULTS Before the operation , there were no significant differences in any of the parameters between the two groups . On the second postoperative day , the atorvastatin group had a lower CRP level ( 7.6+/-0.5 versus 11.7+/-1.3 mg/dl , P<0.0001 ) , a shorter AF duration ( 177+/-57 versus 534+/-189 s , P<0.0001 ) , a longer AERP ( 138+/-6 versus 130+/-6 ms , P<0.01 ) , and a shorter intra-atrial conduction time ( 46+/-3 versus 51+/-5 ms , P<0.01 ) than the control group . CONCLUSIONS Atorvastatin can prevent maintenance of AF by inhibiting inflammation in the canine sterile pericarditis model . Atorvastatin may thus be a novel therapeutic agent for AF BACKGROUND Conventional dual-chamber pacing maintains atrioventricular synchrony but results in high percentages of ventricular pacing , which causes ventricular desynchronization and has been linked to an increased risk of atrial fibrillation in patients with sinus-node disease . METHODS We r and omly assigned 1065 patients with sinus-node disease , intact atrioventricular conduction , and a normal QRS interval to receive  conventional dual-chamber pacing ( 535 patients ) or dual-chamber minimal ventricular pacing with the use of new pacemaker features design ed to promote atrioventricular conduction , preserve ventricular conduction , and prevent ventricular desynchronization ( 530 patients ) . The primary end point was time to persistent atrial fibrillation . RESULTS The mean ( + /-SD ) follow-up period was 1.7+/-1.0 years when the trial was stopped because it had met the primary end point . The median percentage of ventricular beats that were paced was lower in dual-chamber minimal ventricular pacing than in conventional dual-chamber pacing ( 9.1 % vs. 99.0 % , P<0.001 ) , whereas the percentage of atrial beats that were paced was similar in the two groups ( 71.4 % vs. 70.4 % , P=0.96 ) . Persistent atrial fibrillation developed in 110 patients , 68 ( 12.7 % ) in the group assigned to conventional dual-chamber pacing and 42 ( 7.9 % ) in the group assigned to dual-chamber minimal ventricular pacing . The hazard ratio for development of persistent atrial fibrillation in patients with dual-chamber minimal ventricular pacing as compared with those with conventional dual-chamber pacing was 0.60 ( 95 % confidence interval , 0.41 to 0.88 ; P=0.009 ) , indicating a 40 % reduction in relative risk . The absolute reduction in risk was 4.8 % . The mortality rate was similar in the two groups ( 4.9 % in the group receiving dual-chamber minimal ventricular pacing vs. 5.4 % in the group receiving conventional dual-chamber pacing , P=0.54 ) . CONCLUSIONS Dual-chamber minimal ventricular pacing , as compared with conventional dual-chamber pacing , prevents ventricular desynchronization and moderately reduces the risk of persistent atrial fibrillation in patients with sinus-node disease . ( Clinical Trials.gov number , NCT00284830 [ Clinical Trials.gov ] . ) OBJECTIVES A r and omized trial was done to compare single-chamber atrial ( AAI ) and dual-chamber ( DDD ) pacing in patients with sick sinus syndrome ( SSS ) . Primary end points were changes in left atrial ( LA ) size and left ventricular ( LV ) size and function as measured by M-mode echocardiography . BACKGROUND In patients with SSS and normal atrioventricular conduction , it is still not clear whether the optimal pacing mode is AAI or DDD pacing . METHODS A total of 177 consecutive patients ( mean age 74 + /- 9 years , 73 men ) were r and omized to treatment with one of three rate-adaptive ( R ) pacemakers  : AAIR ( n = 54 ) , DDDR with a short atrioventricular delay ( n = 60 ) ( DDDR-s ) , or DDDR with a fixed long atrioventricular delay ( n = 63 ) ( DDDR-l ) . Before pacemaker implantation and at each follow-up , M-mode echocardiography was done to measure LA and LV diameters . Left ventricular fractional shortening ( LVFS ) was calculated . Analysis was on an intention-to-treat basis . RESULTS Mean follow-up was 2.9 + /- 1.1 years . In the AAIR group , no significant changes were observed in LA or LV diameters or LVFS from baseline to last follow-up . In both DDDR groups , LA diameter increased significantly ( p < 0.05 ) , and in the DDDR-s group , LVFS decreased significantly ( p < 0.01 ) . Atrial fibrillation was significantly less common in the AAIR group , 7.4 % versus 23.3 % in the DDDR-s group versus 17.5 % in the DDDR-l group ( p = 0.03 , log-rank test ) . Mortality , thromboembolism , and congestive heart failure did not differ between groups . CONCLUSIONS During a mean follow-up of 2.9 + /- 1.1 years , DDDR pacing causes increased LA diameter , and DDDR pacing with a short atrioventricular delay also causes decreased LVFS . No changes occur in LA or LV diameters or LVFS during AAIR pacing . Atrial fibrillation is significantly less common during AAIR pacing OBJECTIVE We hypothesized that a new minimal ventricular pacing mode ( MVP ) that provides AAI/R pacing with ventricular monitoring and back-up DDD/R pacing as needed during AV block ( AVB ) would significantly reduce cumulative percent ventricular pacing compared to DDD/R. BACKGROUND Conventional DDD/R mode often results in high cumulative percent ventricular pacing that may adversely affect ventricular function and increase risk of heart failure and atrial fibrillation . METHODS MVP was made operational in 30 patients with DDD/R implantable cardioverter-defibrillators ( ICDs ) and no history of AVB . Patients were r and omized to one week each in DDD/R and MVP . Holter monitor recordings ( ECG , intracardiac electrograms , and event markers ) and device diagnostics were analyzed for cumulative % atrial paced ( Cum%AP ) , cumulative percent ventricular pacing , and frequency and duration of DDD/R pacing back-up . Diaries were used to report symptoms . RESULTS Age of the study population was 61 years + /- 12 years and 83 % were male . Baseline PR interval was 204 ms + /- 32 ms and programmed AV intervals ( DDD/R ) were 200 ms + /- 50 ms (paced)/167 ms + /- 54 ms ( sensed ) . Cum%AP was similar between MVP and DDD/R ( 47.9 + /- 37 vs 46.3 + /- 36 ) . Cumulative percent ventricular pacing was significantly lower in MVP vs DDD/R ( 3.79 + /- 16.3 vs 80.6 + /- 33.8 , P < .0001 ) . Back-up DDD/R pacing during MVP operation due to transient AVB occurred in 10 % of patients ( 9.3 + /- 7.4 [ range 1 - 15 ] episodes/patient-day , duration 39.7 minutes + /- 156 minutes ) . Fifteen percent of AV intervals during MVP operation exceeded 300 ms . No significant symptoms were reported during MVP operation . CONCLUSIONS MVP dramatically reduced cumulative percent ventricular pacing compared to DDD/R while maintaining AV synchrony and providing sensor-modulated atrial pacing support . Intermittent oscillations between MVP and DDD/R during transient AV block appeared safe and well tolerated INTRODUCTION Newer implantable pulse generators have data storage capabilities that permit detection of multiple episodes of atrial fibrillation ( AF ) . This study evaluated the clinical predictors and time course of AF development in a general pacemaker population . METHODS AND RESULTS Patients ( n = 231 ) received DDDR pacemakers with features that permit detection and storage of information about the date , time of onset , and duration of multiple , sequential episodes of AF . Patients were followed for 718+/-383 days . Time to first occurrence of AF , interval between first and second episode of AF , and total AF burden were determined at each follow-up visit . AF occurred more often in patients ( 68 % ) with sinus node disease than in patients with AV block ( 37 % ; P < 0.001 ) . Time to first occurrence of AF was 21.2 days ( 95 % confidence interval [ CI ] 14.7 to 30.6 days ) after pacemaker implantation . AF burden initially decreased significantly in patients ( 0.8 hours/day , 95 % CI 0.7 to 0.9 at 8 weeks after implant vs 0.6 hours/day , 95 % CI 0.4 to 0.8 at 12 months after implant ; P = 0.005 ) but then increased significantly during long-term follow-up ( 2.0 hours/day , 95 % CI 1.0 to 3.7 at 48 months after implant ; P = 0.008 ) . The long-term increase in AF burden was seen predominantly in patients with sinus node disease . A prior history of AF and the duration of follow-up were independent predictors of AF occurrence . CONCLUSION AF develops frequently after dual-chamber pacemaker implantation . AF burden increases progressively over the long term BACKGROUND Compared to atrioventricular sequential pacing , ventricular dem and pacing is known to have somewhat more deleterious hemodynamic effects , which probably arise from increased sympathetic tonus and inappropriate baroreceptor activation . Endothelial function is affected by various local and systemic factors including baroreceptor activity . The aim of this study was to explore whether cardiac pacing would have any effect on endothelial functions . METHODS Twelve patients ( six male , mean age : 75 + /- 9 years ) with previously implanted DDD or VDDcardiac pacemakers were included . All patients had stable atrial rhythms during the study . Patients were r and omized to either atrial-based pacing mode ( VDD or DDD ) or ventricular dem and pacing mode ( VVI ) first , and then cross-over was performed with the other pacing mode . Endothelial function was assessed by brachial artery ultrasonography . Basal diameter of the brachial artery , and both flow-mediated dilation ( FMD ) and endothelium-independent vasodilation with nitroglycerin were measured 1 hour after each pacing mode . RESULTS Compared to atrial-based pacing mode , ventricular dem and pacing was associated with a significantly worse FMD both as absolute and percentage values ( 0.17 + /- 0.09 mm vs 0.28 + /- 0.11 mm , P = 0.015 and 4.84 + /- 2.37 % vs 7.00 + /- 2.88 % , P = 0.028 , respectively ) . However , there was no significant difference in nitroglycerin-mediated vasodilation values between the two pacing sessions . CONCLUSIONS Acute ventricular dem and pacing ( VVI pacing ) is clearly associated with attenuation of FMD in patients with atrial-based pacing systems . The attenuation of endothelial vasodilation might have a role in hemodynamic and clinical deterioration in patients with VVI pacemakers Background —It has been suggested that inflammation can have a role in the development of atrial arrhythmias after cardiac surgery and that a genetic predisposition to develop postoperative complications exists . This study was conceived to verify if a potential genetic modulator of the systemic inflammatory reaction to cardiopulmonary bypass ( the −174 G/C polymorphism of the promoter of the Interleukin-6 gene ) has a role in the pathogenesis of postoperative atrial fibrillation ( AF ) . Patients and Results —In 110 primary isolated coronary artery bypass patients the −174G/C Interleukin-6 promoter gene variant was determined . Interleukin-6 , fibrinogen and C-reactive protein plasma levels were determined preoperatively , 24 , 48 , and 72 hours after surgery and at discharge . Heart rate and rhythm were continuously monitored for the first 36 to 48 hours ; daily 12-lead electrocardiograms were performed thereafter until discharge . GG , CT , and CC genotypes were found in 62 , 38 , and 10 patients , respectively . Multivariate analysis ( which included genotype , age , sex , and classical risk factors for AF ) identified the GG genotype as the only independent predictor of postoperative AF . The latter occurred in 33.9 % of GG versus 10.4 % of non-GG patients ( hazard ratio 3.25 , 95%CI 1.23 to 8.62 ) . AF patients  had higher blood levels of Interleukin-6 and fibrinogen after surgery ( P < 0.001 for difference between the area under the curve ) . Conclusion —The −174G/C Interleukin-6 promoter gene variant appears to modulate the inflammatory response to surgery and to influence the development of postoperative AF . These data suggest an inflammatory component of postoperative atrial arrhythmias and a genetic predisposition to this complication BACKGROUND Atrial fibrillation ( AF ) is not always accompanied by clear-cut symptoms and symptoms suggestive of AF may not correspond to a genuine AF episode . The study prospect ively evaluated the burden of asymptomatic AF episodes in pacemaker patients ( for sick sinus syndrome ) with a history of documented paroxysmal AF . METHODS Consecutive patients were enrolled and implanted with dual-chamber pacemakers equipped with diagnostic features for AF monitoring .  Each patient was instructed about typical AF symptoms and was asked to keep a detailed log of symptoms . Stored pacemaker data were analyzed using only AF episodes > 30 s. RESULTS The mean follow-up was 16 + /- 6 months and 102 patients were enrolled ( 73 + /- 7 years , 59 M ) . Thirteen patients ( 13 % ) dropped out with the development of permanent AF and their data were discarded . Twenty-three patients ( 26 % ) without device-stored AF episodes all reported at least one annotated AF episode . There were 1,245 device-stored AF episodes in 66 ( 74 % ) out of 89 patients . Patients reported 1,141 episodes of AF-related symptoms . Only 240 ( 21 % ) corresponded to a genuine device-stored AF event . The sensitivity and positive predictive value of symptoms to detect AF were respectively 19 % and 21 % . Episode duration , rate increase at the onset of the arrhythmia , heart disease , or antiarrhythmic drug therapy showed no statistically significant differences comparing symptomatic and asymptomatic episodes . CONCLUSIONS Many pacemaker patients with paroxysmal AF can develop AF-like symptoms in the absence of device-stored AF . AF-related symptoms have low sensitivity and low positive predictive value in patients with permanent pacemakers OBJECTIVES The present study determined the incidence and time course of atrial fibrillation ( AF ) recurrences  in patients with a history of AF and fitted with an implantable monitoring device .  BACKGROUND The long-term risk of undetected recurrence of AF in patients receiving stable antiarrhythmic therapy remains uncertain . METHODS In 110 patients with a class I indication for physiologic pacing and a history of AF , a pacemaker with dedicated functions for AF detection and electrogram storage was implanted , and antiarrhythmic drug treatment was optimized . Patients were regularly followed up with evaluation of AF-related symptoms , a  resting electrocardiogram ( ECG ) , and  interrogation of device memory .  The incidence of AF recurrences lasting > 48 h in asymptomatic patients presenting in sinus rhythm ( SR ) at the respective follow-up visit constituted the primary end point of this prospect i ve study . RESULTS During 19 + /- 11 months , 678 follow-up visits were performed . Atrial fibrillation was documented in 51 patients ( 46 % ) by ECG recording and in 97 patients ( 88 % ) by a review of stored electrograms ( p < 0.0001 ) . Device interrogation revealed AF recurrences lasting > 48 h in 50 patients , 19 of whom ( 38 % ) were completely asymptomatic and in SR at subsequent follow-up . In 11 ( 16 % ) of 67 patients with device-confirmed freedom from AF for > or =3 months , AF lasting > 48 h recurred subsequently . CONCLUSIONS This prospect i ve study demonstrates a high incidence of recurrent AF despite optimized antiarrhythmic therapy . Of particular note , AF relapses > 48 h remained totally asymptomatic in a significant proportion of patients . Freedom from AF for > or =3 months did not preclude subsequent long-lasting AF recurrence Atrial  fibrillation ( AF ) is prevalent in the elderly , in patients with hypertension , and in patients with coronary artery disease ( CAD ) . We hypothesized that statin therapy might be effective in preventing AF in patients with CAD and examined this hypothesis in a sample of patients with chronic stable CAD without AF , followed prospect ively at a large outpatient cardiology practice . The association between statin use and the risk of developing AF was examined univariately and then with adjustment for potential confounding factors . Four hundred forty-nine men and women between the ages of 40 and 87 years were followed for an average of 5 years . Fifty-two patients ( 12 % ) developed AF during follow-up . Statin therapy was used by 59 % of the patients during the study period and was associated with a significantly reduced risk of developing AF ( crude odds ratio , 0.48 , 95 % confidence interval 0.28 to 0.83 ) . This association remained significant after adjustment for potential confounders , including age , hypertension , left ventricular systolic function , occurrence of heart failure or acute ischemic events , and baseline cholesterol and changes in cholesterol levels ( adjusted odds ratio 0.37 , 95 % confidence interval 0.18 to 0.76 ) . Use of  statins in patients with chronic stable CAD appears to be protective against AF . The underlying mechanism for this effect is unknown but appears to be independent of the reduction in serum cholesterol levels
target: Statistical heterogeneity between included studies was not detected ( chi(2 ) = 1.68 , P = 0.43 , I(2 ) = 0 % ) , although significant clinical differences were found in terms of study design , patient population s , statins use and dosage and AF-monitoring capabilities .
  Statins may represent a novel treatment strategy to prevent the occurrence of AF in patients with PM , especially for those who had a PM implanted due to sinus node dysfunction .
background: Patients with permanent pacemakers ( PM ) are at high risk of developing atrial fibrillation ( AF ) .
  Minimal ventricular pacing modalities have been demonstrated to reduce AF in such patients , although they are not suitable for patients with advanced atrioventricular conduction disease .
  Recent evidence s suggest that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors ( i.e. statins ) may represent a new strategy to prevent AF in patients at risk .
  In this article , we sought to review data regarding the effectiveness of statin therapy in preventing AF patients with a PM .