Comparison between atrial fibrillation-triggered implantable cardioverter-defibrillator (ICD) shocks and inappropriate shocks caused by lead failure: different impact on prognosis in clinical practice. Competing risk analysis of cause-specific mortality in patients with an implantable cardioverter-defibrillator: The EVADEF cohort study. Association between atrial fibrillation and appropriate implantable cardioverter defibrillator therapy: results from a prospective study. Impact of atrial fibrillation on early complications and one year-survival after cardioverter defibrillator implantation: results from the German DEVICE registry. Association Between Use of Primary Prevention Implantable Cardioverter-Defibrillators and Mortality in Patients with Heart Failure: A Prospective Propensity-Score Matched Analysis from the Swedish Heart Failure Registry. Prognostic importance of atrial fibrillation in implantable cardioverter-defibrillator patients. Predictors of early mortality in implantable cardioverter-defibrillator recipients Outcomes of cardiac resynchronization therapy in patients with intermittent atrial fibrillation or atrial flutter in the COMPANION trial. Mechanisms Underlying the Lack of Effect of Implantable Cardioverter-Defibrillator Therapy on Mortality in High-Risk Patients With Recent Myocardial Infarction: Insights from the Defibrillation in Acute Myocardial Infarction Trial (DINAMIT) Impact of Implantable Cardioverter-Defibrillator, Amiodarone, and Placebo on the Mode of Death in Stable Patients With Heart Failure: Analysis From the Sudden Cardiac Death in Heart Failure Trial Japanese randomized trial for investigation of a combined therapy of amiodarone and implantable cardioverter defibrillator in patients with ventricular tachycardia and fibrillation: the Nippon ICD Plus Pharmachologic Option Necessity study design. Canadian Implantable Defibrillator Study (CIDS): study design and organization. CIDS Co-Investigators. Heart Failure and the Risk of Shocks in Patients With Implantable Cardioverter Defibrillators: Results From the Triggers Of Ventricular Arrhythmias (TOVA) Study Effectiveness of implantable cardioverter-defibrillators in patients with ischemic heart disease and left ventricular dysfunction. Factors influencing appropriate firing of the implanted defibrillator for ventricular tachycardia/fibrillation: findings from the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II). The association between atrial fibrillation and sudden cardiac death: the relevance of heart failure. Optimal heart failure therapy and successful cardioversion in heart failure patients with atrial fibrillation.
INTRODUCTION Recent studies suggest a worse impact of inappropriate shock therapies on the outcome of patients with an implantable cardioverter-defibrillator ( ICD ) .  However , it is not known whether the worse impact is attributed to the ICD shock itself or due to the underlying heart disease . The aim of the study was to evaluate the impact of inappropriate ICD shocks on clinical outcome by comparing ICD shocks triggered by atrial fibrillation ( AF ) with shocks caused by lead failure . METHODS AND RESULTS A total of 1,411 consecutive patients of the prospect i ve single-center ICD-registry Ludwigshafen who underwent an ICD implantation between 1992 and 2008 for primary or secondary prevention of sudden cardiac death were analyzed . During the median follow-up of 3 years , 297 ( 21 % ) patients experienced inappropriate ICD shocks . Sixty percent of patients had inappropriate shocks due to AF and 24 % due to lead defect or T-wave oversensing . Multiple ICD shocks ( ≥2 ) triggered by AF were associated with a worse prognosis , whereas a single shock due to AF or 1 or multiple shocks result ing from lead failure were not . ICD shocks caused by AF occurred more often in t and em with a serious adverse event than in patients with a lead failure ( 15 % vs 6 % , P < 0.05 ) . CONCLUSION Multiple ICD shocks triggered by AF are associated with a worse prognosis in ICD patients , whereas a single shock due to AF or shocks result ing from lead failure are not . These data support that the ICD shock itself has no worse impact on the outcome of ICD patients BACKGROUND Although implantable cardioverter-defibrillator ( ICD ) therapy has been evaluated in r and omized controlled trials , enrolling highly selected patients , mortality events in ICD patients have received little attention in routine medical care . We sought to assess the 24-month total and cause-specific mortality rates and their predictors in " real life " patients with an ICD . METHODS The Evaluation Médico-Economique du Défibrillateur Automatique Implantable study was a French multicenter , prospect i ve , observational cohort study of ICD patients with a 2-year follow-up . Cause-specific mortality rates and predictors at implantation of  sudden cardiac death ( SCD ) or progressive heart failure ( HF ) death were assessed using competing risk methodology . RESULTS From June 2001 to June 2003 , 2,296 unselected patients were implanted and followed until June 2005 . During a mean follow-up of 20.5 + /- 6.7 months , 274 deaths occurred : 29 ( 10.6 % ) were SCD and 146 ( 53.3 % ) were HF deaths , corresponding to 24-month cause-specific mortality rates of 1.4 % ( 95 % confidence interval 0.9%-1.9 % ) and 6.9 % ( 95 % confidence interval 5.8%-8.0 % ) , respectively . Among the characteristics at implantation , ejection fraction ( EF ) < 30 % and history of atrial fibrillation were independently associated with SCD ; age , high New York Heart Association class , systemic hypertension , prior atrial fibrillation , QRS duration , EF < 30 % , and lack of beta-blocker therapy were independently associated with HF death . CONCLUSIONS In this large cohort of " daily " patients , the 2-year incidence of SCD ( 1.4 % ) was comparable with the event rate observed in r and omized controlled trials ; HF remained the predominant mode of death . An EF < 30 % at implantation appears to be the most important predictor of ICD-unresponsive SCD INTRODUCTION  Atrial fibrillation ( AF ) is associated with significant morbidity and mortality that may be related to hemodynamic impairment , thromboembolic events , or enhanced electrical instability of the ventricular myocardium . There is , however , a lack of data concerning the association of AF and ventricular tachyarrhythmias . METHODS AND RESULTS Consecutive patients with indication for an implantable cardioverter defibrillator ( ICD ) were classified for the presence or absence of persistent AF at the time of device implantation .  Incidence of device therapy , stored electrograms , and clinical events during follow-up were evaluated prospect ively . Two hundred fifty patients were included . During follow-up ( 20+/-14 months ) , patients in AF experienced appropriate device therapy for recurrent ventricular arrhythmias more frequently compared with patients in sinus rhythm ( SR ) ( 63 % vs 38 % , P = 0.01 ) . On multivariate analysis , AF was an independent predictor of appropriate ICD therapy ( relative risk 1.8 ; 95 % confidence interval [ CI ] 1.2 to 2.9 ) and inappropriate device therapy ( relative risk 2.3 ; 95 % CI 1.2 to 4.5 ) . Predefined clinical events ( cluster endpoint : death , syncope , and hospitalizations ) were observed more frequently in AF than in SR patients ( 55 % vs 31 % , P = 0.01 ) . Analysis of device-stored electrograms revealed a higher incidence of short-long-short cycles preceding ventricular arrhythmias in AF compared with SR patients ( 50 % vs 16 % , P = 0.002 ) . Baseline heart rate preceding ventricular arrhythmias did not differ between the two groups . CONCLUSION AF is an independent predictor of recurrent ventricular arrhythmias in ICD recipients . The underlying electrophysiologic mechanism seems to be irregular rather than rapid ventricular activation , with a high incidence of short-long-short sequences preceding ventricular tachyarrhythmias in AF patients AIMS AND OBJECTIVE Outcome data of patients with implantable cardioverter defibrillators ( ICD ) and atrial fibrillation ( AF ) are conflicting . The German DEVICE registry aims to add further information on this particular cohort . METHODS AND RESULTS The German DEVICE registry is a nationwide prospect i ve multicenter data base of ICD implantations . 3261 patients are included ( 81 % males , 2701 ( 82.8 % ) first ICD implantations , 560 ( 17.2 % ) ICD replacements ) .  Cardiac resynchronization therapy ( CRT-D ) was performed in 882 patients ( 27.0 % ) . Sinus rhythm ( SR ) was present in 2654 ( 81.4 % ) and atrial fibrillation ( AF ) in 607 ( 18.6 % ) . Left ventricular ejection fraction ( LVEF ) did not differ between groups ( SR 32.3 % , AF 30.4 % ; p = 0.09 ) . AF patients were older ( AF 70.9 versus SR 63.9 years ; p < 0.0001 ) , presented with more co-morbidities ( diabetes , hypertension , chronic kidney disease ; all p < 0.001 ) . In-hospital complications were not significantly different between groups ( p = 0.58 ) . Follow-up information after one year was available in 2967 patients ( 91 % ) . One-year overall mortality after first ICD implantation was 4.9 % for SR and 11.2 % for AF patients ( p < 0.0001 ) ; mortality one year after ICD replacement was 8.4 % for SR and 12.0 % for AF ( p = 0.34 ) . No statistically significant difference between SR and AF patients receiving a CRT device was observed ( SR 6.9 % , AF 10.7 % , p = 0.16 ) in terms of one-year mortality . CONCLUSION The German DEVICE registry demonstrates that patients with AF who receive ICD devices are older , have more co-morbidity and more severe heart failure . AF carries an independent 1.39 fold risk ( 95 % CI 1.02 - 1.89 ) of death after one year in patients only with first ICD implantation BACKGROUND Most r and omized trials on implantable cardioverter-defibrillator ( ICD ) use for primary prevention of sudden cardiac death in heart failure with reduced ejection fraction ( HFrEF ) enrolled patients > 20 years ago . We investigated the association between ICD use and all-cause mortality in a contemporary HFrEF cohort and examined relevant subgroups . METHODS Patients from the Swedish HF Registry ( SwedeHF ) fulfilling the European Society of Cardiology criteria for primary prevention ICD were included . The association between ICD use and 1-year and 5-year all-cause and cardiovascular ( CV ) mortality was assessed by Cox Regression models in a 1:1 propensity score matched cohort and in prespecified subgroups . RESULTS Of 16,702 eligible patients , only 1,599 ( 10 % ) had an ICD . After matching , 1,305 ICD recipients were compared to 1,305 non-recipients . ICD use was associated with a reduction in all-cause mortality risk within 1 year [ hazard ratio ( HR ) : 0.73 , 95 % confidence interval ( CI ) : 0.60 - 0.90 ] and 5 years ( HR : 0.88 , 95%CI : 0.78 - 0.99 ) . Results were consistent in all subgroups including patients with vs. without ischemic heart disease , males vs. females , in those aged < 75 vs. ≥75 years , in those with earlier vs. later enrollment in SwedeHF and in patients with vs. without cardiac resynchronization therapy . CONCLUSIONS In a contemporary HFrEF population , ICD for primary prevention was underused although it was associated with reduced short- and long-term all-cause mortality . This association was consistent across all the investigated subgroups . These results call for better implementation of ICD therapy OBJECTIVES This study aim ed to assess the prevalence of different types of  atrial fibrillation ( AF ) and their prognostic importance in  implantable cardioverter-defibrillator ( ICD ) patients . BACKGROUND The prevalence of AF has taken epidemic proportions in the population with cardiovascular disease . The prognostic importance of different types of AF in ICD patients remains unclear . METHODS Data on 913 consecutive patients ( 79 % men , mean age 62 + or - 13 years ) receiving an ICD at the Leiden University Medical Center were prospect ively collected . Among other characteristics , the existence and type of AF ( paroxysmal , persistent , or permanent ) were assessed at implantation . During follow-up , the occurrence of appropriate or inappropriate device therapy as well as mortality was noted . RESULTS At implantation , 73 % of patients had no history of AF , 9 % had a history of paroxysmal AF , 7 % had a history of persistent AF , and 11 % had permanent AF . During 833 + or - 394 days of follow-up , 117 ( 13 % ) patients died , 228 ( 25 % ) patients experienced appropriate device discharge , and 139 ( 15 % ) patients received inappropriate shocks . Patients with permanent AF exhibited more than double the risk of mortality , ventricular arrhythmias triggering device discharge , and inappropriate device therapy .  Patients with paroxysmal or persistent AF did not show a significant increased risk of mortality or appropriate device therapy but demonstrated almost 3 times the risk of inappropriate device therapy . CONCLUSIONS In the population currently receiving ICD treatment outside the setting of clinical trials , a large portion has either a history of AF or permanent AF . Both types of AF have prognostic implication s for mortality and appropriate as well as inappropriate device discharge Aims Multiple trials have shown that implantable cardioverter defibrillators ( ICDs ) prolong survival in secondary and primary prevention population s. However , in spite of the efficacy of these devices in terminating life-threatening arrhythmias , total mortality remains high . Methods and results We evaluated 1703 patients ( mean age : 67 ± 12 years , 82 % male ) with conventional ICD indications , who were enrolled and followed between 2001 and 2004 at 128 US centres . Patients were followed for up to a year , and vital status was obtained for 1655 patients ( 97 % , median follow-up : 377 days ) . There were 183 deaths within 1 year of ICD implantation ( 1-year mortality rate : 16 % ) . Predictors of mortality included a history of atrial fibrillation ( AF , P < 0.0001 ) , diabetes ( P = 0.0001 ) , failure to use cholesterol-lowering medications ( P < 0.001 ) , use of digitalis and derivatives ( P < 0.0001 ) , use of diuretics ( P < 0.0001 ) , low body mass index ( BMI , P < 0.0001 ) , increasing age ( P < 0.0001 ) , low left ventricular ejection fraction ( P < 0.0001 ) , low activity hours ( P < 0.0001 ) , elevated resting heart rate ( P = 0.014 ) , low mean arterial pressure ( MAP , P = 0.007 ) , and poor functional status ( New York Heart Association class , P < 0.0001 ) . In multivariate modelling , AF ( P ≤ 0.001 ) , diabetes ( P = 0.004 ) , BMI ( P = 0.001 ) , MAP ( P = 0.040 ) , and functional class ( P = 0.006 ) predicted mortality . Conclusion In this population undergoing ICD implantation , poor functional status , low MAP , diabetes , low BMI , and AF were strongly associated with death within a year BACKGROUND Controlled clinical trial data are lacking for cardiac resynchronization therapy ( CRT ) outcomes in patients with advanced heart failure ( HF ) from reduced left ventricular ejection fraction ( HFrEF ) and intermittent atrial fibrillation or flutter ( IAF/AFL ) . OBJECTIVE The purpose of this study was to describe CRT outcomes in patients with IAF/AFL and advanced HF . METHODS HF outcomes in patients in the COMPANION ( Comparison of Medical Therapy , Pacing , and Defibrillation in Heart Failure ) trial with New York Heart Association class III or IV HFrEF , left ventricular ejection fraction ≤0.35 , sinus rhythm at r and omization , and no history of baseline arrhythmia were compared with those with a history of IAF/AFL . RESULTS In those with no history of baseline arrhythmia ( n = 887 ) , compared with optimal pharmacological therapy ( OPT ) with no CRT , the CRT + OPT arms exhibited a significant reduction in the end points of death or any hospitalization ( hazard ratio [ HR ] 0.73 [ 95 % Confidence Interval ( CI ) : 0.60 to 0.89 ] ; P = .002 ) and death or HF hospitalization ( HR 0.53 [ 95 % CI : 0.41 to 0.68 ] ; P < .001 ) . In contrast , in the IAF/AFL subgroup ( n = 293 ) , CRT did not result in improved outcomes compared with OPT ( death or any hospitalization : HR 1.16 [ 95 % CI : 0.83 to 1.63 ] ; P = .38 ; death or HF hospitalization : HR 0.97 [ 95 % CI : 0.64 to 1.46 ] ; P = .88 ) . The interaction between history of AF/AFL and CRT was statistically significant for both outcomes ( P < .05 ) . CONCLUSION In the COMPANION trial , patients with moderate to severe HFrEF and a history of IAF/AFL had no benefit from CRT Background — Although implantable cardioverter-defibrillators ( ICDs ) lower mortality in stable patients with low ejection fraction late after myocardial infa rct ion , r and omized trials of ICD versus control subjects implanted early after myocardial infa rct ion do not show mortality benefit . Our objective was to investigate possible mechanisms underlying the lack of mortality benefit in the Defibrillation in Acute Myocardial Infa rct ion Trial ( DINAMIT ) . Methods and Results — This is a secondary analysis of the prospect i ve r and omized clinical trial . Out patients with recent ( 6 to 40 days ) acute myocardial infa rct ion , left ventricular dysfunction ( ejection fraction < 35 % ) , and low heart rate variability were r and omized to ICD ( n=311 ) or to st and ard medical therapy  ( n=342 ) . In a competing-risks analysis , those factors that increased the risk of arrhythmic death also increased the risk of nonarrhythmic deaths . After adjustment for these factors , receiving an ICD was associated with a decreased risk of arrhythmic death ( hazard ratio , 0.33 ; 95 % confidence interval , 0.15 to 0.71 ) but an increase in nonarrhythmic death ( hazard ratio , 1.70 ; 95 % confidence interval , 1.00 to 2.80 ) . In an adjusted time-dependent analysis , patients receiving an ICD and having appropriate ICD therapy had a 15.1 % yearly hazard of mortality compared with 5.2 % in ICD patients with no appropriate therapy ( P<0.001 ) . The reduction in sudden death in ICD patients was completely offset by increased nonarrhythmic deaths , which were greatest in patients receiving ICD shock therapy ( hazard ratio , 6.0 ; 95 % confidence interval , 2.8 to 12.7 ) . Conclusions — In patients receiving ICDs early after myocardial infa rct ion , those factors that are associated with arrhythmia requiring ICD therapy are also associated with a high risk of nonsudden death , negating the benefit of ICDs in this setting Background — The Sudden Cardiac Death in Heart Failure Trial ( SCD-HeFT ) demonstrated that implantable cardioverter-defibrillator ( ICD ) therapy reduces all-cause mortality in patients with New York Heart Association class II/III heart failure and a left ventricular ejection fraction ≤35 % on optimal medical therapy . Whether ICD therapy reduced sudden death caused by ventricular tachyarrhythmias without affecting heart failure deaths in this population is unknown . Methods and Results — SCD-HeFT r and omized 2521 subjects to placebo , amiodarone , or shock-only , single-lead ICD therapy .  Over a median follow-up of 45.5 months , a total of 666 deaths occurred , which were review ed by an Events Committee and initially categorized as cardiac or noncardiac . Cardiac deaths were further adjudicated as result ing from sudden death presumed to be ventricular tachyarrhythmic , bradyarrhythmia , heart failure , or other cardiac causes . ICD therapy significantly reduced cardiac mortality compared with placebo ( adjusted hazard ratio , 0.76 ; 95 % confidence interval , 0.60 to 0.95 ) and tachyarrhythmia mortality ( adjusted hazard ratio , 0.40 ; 95 % confidence interval , 0.27 to 0.59 ) and had no impact on mortality result ing from heart failure or noncardiac causes . The cardiac and tachyarrhythmia mortality reductions were evident in subjects with New York Heart Association class II but not in subjects with class III heart failure . The reduction in tachyarrhythmia mortality with ICD therapy was similar in subjects with ischemic and nonischemic disease . Compared with placebo , amiodarone had no significant effect on any mode of death . Conclusions — ICD therapy reduced cardiac mortality and sudden death presumed to be ventricular tachyarrhythmic in SCD-HeFT and had no effect on heart failure mortality . Amiodarone had no effect on all-cause mortality or its cause-specific components , except an increase in non-cardiac mortality in class III patients . Clinical Trial Registration Information— URL : http://www . clinical trials.gov . Unique identifier : NCT00000609 BACKGROUND Implantable cardioverter-defibrillators ( ICDs ) are the most effective therapy in reducing the mortality of patients with life-threatening ventricular tachyarrhythmias . However , the ICD can not prevent the recurrence of tachycarida attacks and that limits the clinical usefulness of them . The Nippon ICD Plus Pharmachologic Option Necessity ( NIPPON ) trial was design ed as the first prospect i ve r and omized study to test the hypothesis whether amiodarone could improve the patient 's clinical outcome by reducing the amount of ICD therapy in the Japanese patient population . METHODS AND RESULTS Approximately 400 patients with organic heart disease and spontaneous episode(s ) of sustained ventricular tachycardia/fibrillation ( VT/VF ) will be r and omly assigned to one of 2 groups ; the amiodarone group and non-amiodarone group . Both groups of patients will be followed at least for 24 months . The end-point committee will adjudicate events in a blinded fashion . The primary end-points of this study are determination of the appropriate therapy from the ICD and alteration of the assigned treatment because of its harmful effects and /or frequent ICD therapies . CONCLUSION The NIPPON study is expected to confirm our underst and ing of the prognostic and therapeutic usefulness of adjuvant amiodarone therapy for patients with an ICD and with a history of sustained VT/VF The Canadian Implantable Defibrillator Study ( CIDS ) is an on-going r and omized multicenter clinical trial that compares implantable cardioverter-defibrillator ( ICD ) therapy against amiodarone in patients with prior cardiac arrest or hemodynamically unstable ventricular tachycardia . Eligible patients are equally r and omized to receive or not receive an ICD as initial management . Those not receiving an ICD receive amiodarone . All patients are seen in follow-up every 6 months . The primary outcome event cluster is arrhythmic death or any other death occurring within 30 days of therapy initiation . Secondary outcomes are all-cause mortality and nonfatal occurrences of ventricular tachycardia or fibrillation . The goal of the study is to recruit 400 patients over 4 years . All patients will be followed to the end of the year . This will result in an 80 % chance of detecting a reduction in arrhythmic death of 58 % by ICD if such a difference in truth exists . Recruitment began in October 1990 and 184 patients have been enrolled to date Background —Left ventricular ejection fraction ( LVEF ) predicts device discharges in patients with implantable cardioverter-defibrillators ( ICDs ) .  The relationship between severity of congestive heart failure ( CHF ) and ICD discharges is less clear . Methods and Results —We prospect ively analyzed the association between CHF and risk of appropriate ICD discharges  in the Triggers Of Ventricular Arrhythmias ( TOVA ) study , a cohort study of ICD patients conducted at 31 centers in the United States . Reported shocks were confirmed for sustained ventricular tachycardia ( VT ) or fibrillation ( VF ) by analysis of stored electrograms . Proportional hazards models included CHF categorized by New York Heart Association class . Baseline CHF was present among 502 ( 44 % ) of 1140 patients ; 170 ( 34 % ) had class I , 230 ( 46 % ) had class II , 97 ( 19 % ) had class III , and only 5 ( 1 % ) had class IV symptoms . During median follow-up of 212 days , 92 patients experienced 1 or more appropriate ICD discharges . Class III CHF was associated in a statistically significantly manner with ICD discharge for VT/VF ( hazard ratio 2.40 , 95 % CI 1.16 to 4.98 ) , even with adjustment for LVEF . The combination of LVEF < 0.20 and class III symptoms result ed in a particularly high risk of shocks for VT/VF ( hazard ratio 3.90 , 95 % CI 1.28 to 11.92 ) . Conclusions —Class III CHF , an easily accessible clinical measure , is an independent risk factor , along with LVEF , for ventricular arrhythmias that require shock therapy among ICD patients . Whether patients with class III CHF benefit to a greater degree from ICDs and whether aggressive treatment of CHF in ICD patients may prevent ventricular arrhythmias remains to be determined BACKGROUND Implantable cardioverter-defibrillators ( ICDs ) have been shown in primary prevention efficacy trials to reduce mortality in patients with ischemic heart disease and left ventricular dysfunction . To investigate the generalizabilty of this mortality reduction , we examined the effectiveness of ICDs in clinical practice . METHODS We developed a prospect i ve multicenter cohort of 770 patients with ischemic left ventricular dysfunction ( ejection fraction < or = 35 % ) and without a history of ventricular arrhythmia , of whom 395 ( 52 % ) received ICDs .  Mean + /- SD follow-up was 27 + /- 12 months . We assessed the degree to which ICDs decreased mortality risk using Cox proportional hazards analyses that controlled for clinical predictors of death , receipt of ICD ( a propensity score analysis ) , and predictors of arrhythmic death ( including electrophysiologic variables ) . RESULTS Multivariate Cox analyses showed that those with ICDs had significantly lower all-cause mortality ( hazard ratio [ HR ] , 0.53 ; 95 % confidence interval [ CI ] , 0.33 - 0.86 ) . This mortality reduction was mediated through dramatically lower arrhythmia-related mortality ( HR , 0.35 ; 95 % CI , 0.17 - 0.73 ) , with no significant effect on cardiovascular nonarrhythmic ( HR , 0.81 ; 95 % CI , 0.34 - 1.96 ) and noncardiovascular ( HR , 0.76 ; 95 % CI , 0.29 - 2.05 ) mortality . No differences were found between the ICD and non-ICD groups for a composite outcome of all-cause mortality , appropriate ICD shocks , or documented symptomatic ventricular arrhythmia , which suggests that the 2 groups had similar baseline risk for life-threatening arrhythmic events ( HR , 0.96 ; 95 % CI , 0.63 - 1.45 ) . CONCLUSION In clinical practice , ICDs appear to reduce all-cause and arrhythmic rates of mortality at levels similar to those found in primary prevention trials OBJECTIVES The purpose of this study was to prospect ively examine the role of clinical , laboratory , echocardiographic , and electrophysiological variables as predictors of appropriate initial implantable cardioverter-defibrillator ( ICD ) therapy for ventricular tachycardia ( VT ) or ventricular fibrillation ( VF ) or death in the Multicenter Automatic Defibrillator Implantation Trial II ( MADIT-II ) population . BACKGROUND There is limited information regarding the determinants of appropriate ICD therapy in patients with reduced ventricular function after a myocardial infa rct ion . METHODS We used secondary analysis in one arm of a multicenter r and omized clinical trial in patients with a previous myocardial infa rct ion and reduced left ventricular function . RESULTS We analyzed baseline and follow-up data on 719 patients enrolled in the ICD arm of the MADIT-II study . Appropriate ICD therapy was observed in 169 subjects . Clinical , laboratory , echocardiographic , and electrophysiological variables , along with measures of clinical instability such as interim hospitalization for congestive heart failure ( IH-CHF ) and interim hospitalization for coronary events ( IH-CE ) , were examined with proportional hazards models and Kaplan-Meier time-to-event curves before and after first interim hospitalization . Interim hospitalization-CHF , IH-CE , no beta-blockers , digitalis use , blood urea nitrogen ( BUN ) > 25 , body mass index ( BMI ) > or = 30 kg/m2 , and New York Heart Association functional class > II were associated with increased risk for appropriate ICD therapy for VT , VF , or death . In a multivariate ( stepwise selection ) analysis , IH-CHF was associated with an increased risk for the end point of either VT or VF ( hazard ratio [ HR ] 2.52 , 95 % confidence interval [ CI ] 1.69 to 3.74 , p < 0.001 ) and for the combined end point of VT , VF , or death ( HR 2.97 , 95 % CI 2.15 to 4.09 , p < 0.001 ) . Interim hospitalization-CE was associated with an increased risk for VT , VF , or death ( HR 1.66 , 95 % CI 1.09 to 2.52 , p = 0.02 ) . CONCLUSIONS These results provide important mechanistic information , suggesting that worsening clinical condition and cardiac instability , as reflected by an IH-CHF or IH-CE , are subsequently associated with a significant increase in the risk for appropriate ICD therapy ( for VT/VF ) and death OBJECTIVES The purpose of this study was to evaluate the role of congestive heart failure ( CHF ) in the association between  atrial fibrillation ( AF ) and sudden cardiac death ( SCD ) .  BACKGROUND Recent studies have reported the possibility of an independent association between AF and SCD . We hypothesized that a history of CHF is a significant confounder of this association . METHODS In a prospect i ve case-control analysis from the community ( The Oregon-SUDS [ Sudden Unexpected Death Study ] , 2002 to 2012 ) , SCD cases ( n = 652 ) with clinical records available ( including electrocardiography and /or echocardiography ) were compared with age- and sex-matched control patients with coronary artery disease . The association between AF and SCD was analyzed using multivariable logistic regression and propensity score matching . RESULTS Cases ( age 67.3 ± 11.7 years , 65 % male ) were more likely than control patients ( age 67.2 ± 11.4 years , 65 % male ) to have a history of AF ( p = 0.0001 ) , myocardial infa rct ion ( p = 0.007 ) , CHF ( p < 0.0001 ) , stroke ( p < 0.0001 ) , and diabetes ( p < 0.0001 ) . In multivariate analysis without considering CHF , AF was a significant predictor of SCD ( odds ratio [ OR ] : 1.6 ; 95 % confidence interval [ CI ] : 1.2 to 2.0 ; p = 0.002 ) . However , in a model that included CHF , the AF-SCD association was no longer significant ( OR : 1.1 ; 95 % CI : 0.8 to 1.5 ; p = 0.45 ) , whereas CHF was a significant predictor of SCD ( OR : 3.1 ; 95 % CI : 2.4 to 4.1 ; p < 0.0001 ) . Results on the basis of propensity score matching were consistent . CONCLUSIONS Our findings suggest that a history of CHF , including both systolic and diastolic symptomatic dysfunction , may partially explain the AF-SCD association BACKGROUND Effectiveness , safety , and other factors associated with success of cardioversion ( CV ) of atrial fibrillation ( AF )  have not yet been evaluated in patients with reduced left ventricular ejection fraction . We studied 148 consecutive patients with left ventricular dysfunction ( ejection fraction < or = 45 % ) , who underwent electrical CV for AF in our department . The patients had New York Heart Association heart failure ranging from class II to IV . The overall CV success rate was 71 % . We relied on univariate and multivariate regression and sought variables influencing success rate . Conversion success did not correlate with New York Heart Association class . Instead , we found that the greatest predictor was the degree of heart failure treatment . Patients receiving beta-blockers , angiotensin-converting enzyme inhibitors or angiotension receptor blockers , plus mineralocorticoid receptor blockers had the greatest chance for conversion success . Success was more likely in patients with coronary artery disease ( 91 % ) than in patients with nonischemic cardiomyopathy . CONCLUSIONS Cardioversion is a safe and effective method for the restoration of sinus rhythm in patients with AF and reduced left ventricular ejection fraction . Our findings underscore the value of aggressive heart failure treatment before CV in patients with AF
Atrial fibrillation history is statistically significantly associated with adverse major clinical outcomes in ICD-implanted HF patients .
Patients with AF have a higher risk of all-cause mortality , appropriate , and inappropriate ICD interventions compared with patients with no AF history .
AIMS To assess the association between atrial fibrillation ( AF ) and all-cause mortality and implantable cardioverter-defibrillators ( ICDs ) therapies  in heart failure ( HF ) patients with reduced ejection fraction and an ICD implanted .