Competing risk analysis of cause-specific mortality in patients with an implantable cardioverter-defibrillator: The EVADEF cohort study. Impact of atrial fibrillation on early complications and one year-survival after cardioverter defibrillator implantation: results from the German DEVICE registry. Sinus rhythm restoration by catheter ablation in patients with long-lasting atrial fibrillation and congestive heart failure: impact of the left ventricular ejection fraction improvement on the implantable cardioverter defibrillator insertion indication. Comparison between atrial fibrillation-triggered implantable cardioverter-defibrillator (ICD) shocks and inappropriate shocks caused by lead failure: different impact on prognosis in clinical practice. Predictors of early mortality in implantable cardioverter-defibrillator recipients 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. Exercise training and implantable cardioverter-defibrillator shocks in patients with heart failure: results from HF-ACTION (Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing). Catheter ablation versus standard conventional treatment in patients with left ventricular dysfunction and atrial fibrillation (CASTLE-AF) - study design. Prognostic importance of atrial fibrillation in implantable cardioverter-defibrillator patients. Implantable cardioverter defibrillators and quality of life: results from the defibrillators in nonischemic cardiomyopathy treatment evaluation study. Impact of sleep-disordered breathing on life-threatening ventricular arrhythmia in heart failure patients with implantable cardioverter-defibrillator. Impact of Age and Medical Comorbidity on the Effectiveness of Implantable Cardioverter-Defibrillators for Primary Prevention Predictors of Implantable Cardioverter Defibrillator Shocks During the First Year Changes in Follow-Up Left Ventricular Ejection Fraction Associated With Outcomes in Primary Prevention Implantable Cardioverter-Defibrillator and Cardiac Resynchronization Therapy Device Recipients. Clinical Outcomes of Single- versus Dual-Chamber Implantable Cardioverter Defibrillators: Lessons from the Israeli ICD Registry. 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 Association between atrial fibrillation and appropriate implantable cardioverter defibrillator therapy: results from a prospective study. Cardiac resynchronization therapy for the treatment of heart failure in patients with intraventricular conduction delay and malignant ventricular tachyarrhythmias. Prognostic value of a restrictive mitral filling pattern in patients with systolic heart failure and an implantable cardioverter-defibrillator. Effect of implantable cardioverter-defibrillator implantation on surgical morbidity in the CABG Patch Trial. Surgical Investigators of the Coronary Artery Bypass Graft Patch Trial. Baseline characteristics of patients in the coronary artery bypass graft (CABG) Patch Trial. Cardiac Resynchronization Therapy in Patients With Permanent Atrial Fibrillation: Results From the Resynchronization for Ambulatory Heart Failure Trial (RAFT) Dual-chamber pacing or ventricular backup pacing in patients with an implantable defibrillator: the Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial.
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 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 AIMS In the setting of congestive heart failure ( CHF ) , atrial fibrillation ( AF ) ablation can improve clinical status and the left ventricular ejection fraction ( LVEF ) value . However , the impact of AF ablation on the implantable cardioverter defibrillator ( ICD ) indication has never been specifically addressed . METHODS AND RESULTS Study subject were six CHF ( mean age 61.1 + /- 6.9 years , mean LVEF 25.8 + /- 7.3 % ) patients refractory to conventional medical treatment with long-lasting AF unresponsive to external cardioversion . Five patients had an idiopathic dilated cardiomyopathy ( DCM ) and one had an ischaemic cardiomyopathy ( ICM ) . Their New York Heart Association ( NYHA ) class was III-IV . Two patients had renal insufficiency . No patient had left ventricular delay . All patients underwent AF ablation .  LVEF and NYHA class were dramatically improved in the five DCM patients . New York Heart Association class , but not the LVEF , was improved in the ICM patient . A redo ablative procedure was undertaken in four of five DCM patients and in the ICM patient due to arrhythmia recurrence . Left ventricular ejection fraction and NYHA were improved again in the DCM patients ( 56 + /- 4.4 % , I-II , respectively ) and led to ICD indication preclusion . The LVEF remained low in the ICM patient ( 30 % ) and led to ICD insertion . Sinus rhythm has been stable during the 18.1 + /- 5.7 months follow-up period . CONCLUSION  Atrial fibrillation ablation in CHF patients can improve both the clinical status of patients and their LVEF , especially among those affected by DCM . The LVEF improvement has the potential to preclude the indication for a primary prevention ICD insertion 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 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 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 The purpose of this study was to determine whether exercise training is associated with an increased risk of implantable cardioverter-defibrillator ( ICD ) therapy  in patients with heart failure ( HF ) . BACKGROUND Few data are available regarding the safety of exercise training in patients with ICDs and HF . METHODS HF-ACTION ( Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing ) r and omized 2,331 out patients with HF and an ejection fraction ( EF ) ≤35 % to exercise training or usual care .  Cox proportional hazards modeling was used to examine the relationship between exercise training and ICD shocks . RESULTS We identified 1,053 patients ( 45 % ) with an ICD at baseline who were r and omized to exercise training ( n = 546 ) or usual care ( n = 507 ) . Median age was 61 years old , and median EF was 24 % . Over a median of 2.2 years of follow-up , 20 % ( n = 108 ) of the exercise patients had a shock versus 22 % ( n = 113 ) of the control patients . A history of sustained ventricular tachycardia/fibrillation ( hazard ratio [ HR ] : 1.93 [ 95 % confidence interval ( CI ) : 1.47 to 2.54 ] ) , previous atrial fibrillation/flutter ( HR : 1.63 [ 95 % CI : 1.22 to 2.18 ] ) , exercise-induced dysrhythmia ( HR : 1.67 [ 95 % CI : 1.23 to 2.26 ] ) , lower diastolic blood pressure ( HR for 5-mm Hg decrease < 60 : 1.35 [ 95 % CI : 1.12 to 1.61 ] ) , and nonwhite race ( HR : 1.50 [ 95 % CI : 1.13 to 2.00 ] ) were associated with an increased risk of ICD shocks . Exercise training was not associated with the occurrence of ICD shocks ( HR : 0.90 [ 95 % CI : 0.69 to 1.18 ] , p = 0.45 ) . The presence of an ICD was not associated with the primary efficacy composite endpoint of death or hospitalization ( HR : 0.99 [ 95 % CI : 0.86 to 1.14 ] , p = 0.90 ) . CONCLUSIONS We found no evidence of increased ICD shocks in patients with HF and reduced left ventricular function  who underwent exercise training . Exercise therapy should not be prohibited in ICD recipients with HF . ( Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure ; NCT00047437 BACKGROUND Electrical isolation of the pulmonary veins by catheter ablation is an emerging treatment modality for the treatment of atrial fibrillation ( AF ) and is increasingly used in patients with heart failure . METHODS The catheter ablation versus st and ard conventional treatment in patients with left ventricular dysfunction and atrial fibrillation trial ( CASTLE-AF ) is a r and omized evaluation of ablative treatment of atrial fibrillation in patients with left ventricular dysfunction . The primary endpoint is the composite of all-cause mortality or worsening of heart failure requiring unplanned hospitalization using a time to first event analysis . Secondary endpoints are all-cause mortality , cardiovascular mortality , cerebrovascular accidents , worsening of heart failure requiring unplanned hospitalization , unplanned hospitalization due to cardiovascular reason , all-cause hospitalization , quality of life , number of therapies ( shock and antitachycardia pacing ) delivered by the implantable cardioverter-defibrillator ( ICD ) , time to first ICD therapy , number of device-detected ventricular tachycardia and ventricular fibrillation episodes , AF burden , AF free interval , left ventricular function , exercise tolerance , and percentage of right ventricular pacing . CASTLE-AF will r and omize 420 patients for a minimum of 3 years at 48 sites in the United States , Europe , Australia , and South America 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 BACKGROUND The Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation study demonstrated that implantable cardioverter defibrillators ( ICDs ) significantly reduce the risk of sudden cardiac death in patients with nonischemic cardiomyopathy and an ejection fraction of 35 % or less , with no statistically significant decrease in overall mortality . The impact of ICD placement and shock on health-related quality of life ( HRQL ) in this population is unknown . METHODS The 12-Item Medical Outcomes Short-Form Health Survey and the Minnesota Living with Heart Failure Question naire were administered to 458 patients with nonischemic cardiomyopathy , an ejection fraction of 35 % or less , and either nonsustained ventricular tachycardia or 10 or more premature ventricular depolarizations per hour at baseline , 1 month after r and omization , and every 3 months thereafter throughout the trial . The subjects were r and omized to an ICD or st and ard medical therapy . Outcomes were compared using hierarchical linear regression . RESULTS Overall , there were no significant differences in HRQL throughout the trial between patients r and omized to an ICD or st and ard medical therapy . However , in patients with 1 or more ICD shocks , HRQL declined 0.5 + /- 0.2 ( mean + /- SD ) points per shock on the emotional scale of the Minnesota Living with Heart Failure Question naire ( P = .04 ) and 1.0 + /- 0.5 points per shock on the mental component score of the 12-Item Medical Outcomes Short-Form Health Survey ( P = .04 ) . CONCLUSIONS Overall , HRQL was not affected by ICD implantation in patients in the Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation study . Implantable cardioverter defibrillator shock was associated with a reduction in some measures of HRQL , but the effects were unlikely to result in a clinical ly observable alteration until 5 or more shocks were experienced It was recognized that sleep-disordered breathing ( SDB ) is associated with cardiac arrhythmia and sudden cardiac death . However , it was unclear whether the presence of SDB increased the risk of life-threatening ventricular arrhythmia in patients with heart failure ( HF ) with an implantable cardioverter-defibrillator ( ICD ) . Seventy-one patients with HF and an ICD who were followed up for 180 days after a sleep study were prospect ively studied . All patients had an ejection fraction < or=35 % . SDB was defined as an apnea-hypopnea index > or=10 events/hour on the sleep study . The frequency of appropriate ICD therapy and the day-night pattern of ICD therapies were compared between patients with and without SDB . SDB was diagnosed in 47 of 71 patients ( 66 % ) . There were no statistical differences between patients with and without SDB in baseline cardiac function . However , appropriate ICD therapies occurred more frequently in patients with ( 43 % ) than without SDB ( 17 % ; p = 0.029 ) . On multivariate analysis , the presence of SDB was an independent predictor for appropriate ICD therapy ( hazard ratio 4.05 , 95 % confidence interval 1.20 to 13.65 , p = 0.015 ) . Moreover , the rate of total ICD therapy from midnight to 6 A.M. was significantly higher in patients with ( 34 % ) than without SDB ( 13 % ; p = 0.046 ) . In conclusion , in patients with HF with an ICD , the presence of SDB was common and an independent predictor of life-threatening ventricular arrhythmias that were more likely to occur during sleep Background —Although implantable cardioverter-defibrillators ( ICDs ) reduce mortality in primary prevention patients with left ventricular systolic dysfunction , recent studies have question ed their overall role in clinical practice , especially in older patients and those with major comorbid conditions . Methods and Results —In a prospect i ve cohort of 965 patients with ischemic and nonischemic cardiomyopathies ( ejection fraction ≤35 % ) and no prior ventricular arrhythmias , we compared long-term mortality in patients who did ( n=494 [ 51 % ] ) and did not receive ICDs over a mean follow-up period of 34±16 months . Using a l and mark analysis , multivariable Cox proportional hazards models that included propensity scores for ICD implantation assessed the relationship between ICD therapy and mortality in the entire cohort and by age and the presence of major comorbid conditions . Data from these analyses were then used as inputs in a Markov model to generate incremental cost-effectiveness ratios for ICD therapy . Patients who received ICDs were similar in age and prevalence of most major comorbid conditions , including symptomatic heart failure . After multivariable adjustment , ICD therapy was associated with a 31 % lower risk for all-cause mortality ( adjusted hazard ratio , 0.69 ; 95 % CI , 0.50 to 0.96 ; P=0.03 ) . The relationship between ICD therapy and lower all-cause mortality was consistent after stratification by age ( < 65 , 65 to 74 , and ≥75 ) , ischemic etiology , ejection fraction ( > 25 % versus ≤25 % ) , and the presence of major comorbid conditions ( probability values for all interactions > 0.05 ) . Incremental cost-effectiveness ratios  for ICD therapy were similar between patients aged ≥75 years and younger patients but rose slightly in those with multiple comorbid conditions . Conclusions —Routine use of ICDs in primary prevention patients with left ventricular systolic dysfunction was associated with lower all-cause mortality , even among older patients and those with major comorbid conditions . Although their use needs to be individualized , our findings suggest that these groups should not be routinely excluded from ICD treatment The purpose of this study was to predict implantable cardioverter defibrillator ( ICD ) shocks using demographic and clinical characteristics in the first year after implantation for secondary prevention of cardiac arrest . A prospect i ve design was used to follow 168 first-time ICD recipients over 12 months . Demographic and clinical data were obtained from medical records at the time of ICD insertion . Implantable cardioverter defibrillator shock data were obtained from ICD interrogation reports at hospital discharge , 3 , 6 , and 12 months . Logistic regression was used to predict ever receiving an ICD shock using background characteristics . Patients received an ICD for secondary prevention of sudden cardiac arrest , they were 64.1 years old , 89 % were white , 77 % were male , with a mean ( SD ) ejection fraction of 33.7 % ( 14.1 % ) . The cumulative percentage of ever receiving an ICD shock was 33.3 % over 1 year . Three variables predicted shocks in the first year : history of chronic obstructive pulmonary disease ( COPD ) ( odds ratio [ OR ] , 4.42 ; 95 % confidence interval [ CI ] , 1.2 - 16.4 ; P = .03 ) , history of congestive heart failure ( OR , 3.55 ; 95 % CI , 1.4 - 9.3 ; P = .01 ) , and documented ventricular tachycardia ( VT ) at the time of ICD implant ( OR , 10.05 ; 95 % Cl , 1.8 - 55.4 ; P = .01 ) . High levels of anxiety approached significance ( OR = 2.82 ; P = .09 ) . The presence of COPD , congestive heart failure , or VT at ICD implant was a significant predictor of receiving an ICD shock in the first year after ICD implantation . Because ICD shocks are distressing , painful , and associated with greater mortality , healthcare providers should focus attention on prevention of shocks by controlling VT , careful management of HF symptoms , reduction of the use of short acting β agonist medications in COPD , and perhaps recognizing and treating high levels of anxiety BACKGROUND Heart failure patients with primary prevention implantable cardioverter-defibrillators ( ICD )  may experience an improvement in left ventricular ejection fraction ( LVEF ) over time . However , it is unclear how LVEF improvement affects subsequent risk for mortality and sudden cardiac death . OBJECTIVES This study sought to assess changes in LVEF after ICD implantation and the implication of these changes on subsequent mortality and ICD shocks . METHODS We conducted a prospect i ve cohort study of 538 patients with repeated LVEF assessment s after ICD implantation for primary prevention of sudden cardiac death . The primary endpoint was appropriate ICD shock defined as a shock for ventricular tachyarrhythmias . The secondary endpoint was all-cause mortality . RESULTS Over a mean follow-up of 4.9 years , LVEF decreased in 13.0 % , improved in 40.0 % , and was unchanged in 47.0 % of the patients . In the multivariate Cox models comparing patients with an improved LVEF with those with an unchanged LVEF , the hazard ratios were 0.33 ( 95 % confidence interval : 0.18 to 0.59 ) for mortality and 0.29 ( 95 % confidence interval : 0.11 to 0.78 ) for appropriate shock . During follow-up , 25 % of patients showed an improvement in LVEF to > 35 % and their risk of appropriate shock decreased but was not eliminated . CONCLUSIONS Among primary prevention ICD patients , 40.0 % had an improved LVEF during follow-up and 25 % had LVEF improved to > 35 % . Changes in LVEF were inversely associated with all-cause mortality and appropriate shocks for ventricular tachyarrhythmias . In patients whose follow-up LVEF improved to > 35 % , the risk of an appropriate shock remained but was markedly decreased OBJECTIVE To compare the clinical outcomes of a single- versus dual-chamber ICD for primary prevention of sudden cardiac death in a large , national ICD registry . METHODS Data were collected from the prospect i ve Israeli ICD Registry . Baseline characteristics and clinical outcomes including mortality , admissions for heart failure ( HF ) , and ICD therapy were compared between the two groups . RESULTS A total of 1,125 subjects , 37 % with a single-chamber and 63 % with a dual-chamber ICD , constructed the baseline cohort . Approximately 80 % had ischemic heart disease ( IHD ) . Mean follow-up was 22 months , mean ejection fraction was 30 % , and mean QRS width was 103 milliseconds in both groups . During follow-up , there were no significant differences in the rate of mortality , admissions for HF , appropriate or inappropriate therapy , or in time to any of the clinical outcomes . Using multivariate analysis , single-chamber ICD was not associated with increased risk of death or admission for HF . In a subgroup of patients with IHD , single-chamber ICD was associated with a higher rate of inappropriate therapy . CONCLUSIONS In this large retrospective population -based cohort , dual-chamber ICD showed no benefit in reducing the incidence of death or HF admissions , whereas in a subgroup of patients with IHD , single-chamber ICD was associated with increased inappropriate therapy . Further prospect i ve studies are necessary to assess the benefit of dual-chamber ICD in reducing the rate of inappropriate therapy 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 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 OBJECTIVES This study was conducted to assess the safety and effectiveness of cardiac resynchronization therapy ( CRT ) when combined with an implantable cardioverter defibrillator ( ICD ) . BACKGROUND Long-term outcome of CRT was measured in patients with symptomatic heart failure ( HF ) , intraventricular conduction delay , and malignant ventricular tachyarrhythmias ( ventricular tachycardia/ventricular fibrillation [ VT/VF ] ) requiring therapy from an ICD . METHODS Patients ( n = 490 ) were implanted with a device capable of providing both CRT and ICD therapy and r and omized to CRT ( n = 245 ) or control ( no CRT , n = 245 ) for up to six months . The primary end point was progression of HF , defined as all-cause mortality , hospitalization for HF , and VT/VF requiring device intervention . Secondary end points included peak oxygen consumption ( VO(2 ) ) , 6-min walk ( 6 MW ) , New York Heart Association ( NYHA ) class , quality of life ( QOL ) , and echocardiographic analysis . RESULTS A 15 % reduction in HF progression was observed , but this was statistically insignificant ( p = 0.35 ) . The CRT , however , significantly improved peak VO(2 ) ( 0.8 ml/kg/min vs. 0.0 ml/kg/min , p = 0.030 ) and 6 MW ( 35 m vs. 15 m , p = 0.043 ) . Changes in NYHA class ( p = 0.10 ) and QOL ( p = 0.40 ) were not statistically significant . The CRT demonstrated significant reductions in ventricular dimensions ( left ventricular internal diameter in diastole = -3.4 mm vs. -0.3 mm , p < 0.001 and left ventricular internal diameter in systole = -4.0 mm vs. -0.7 mm , p < 0.001 ) and improvement in left ventricular ejection fraction ( 5.1 % vs. 2.8 % , p = 0.020 ) . A subgroup of patients with advanced HF ( NYHA class III/IV ) consistently demonstrated improvement across all functional status end points . CONCLUSIONS The CRT improved functional status in patients indicated for an ICD who also have symptomatic HF and intraventricular conduction delay In patients with chronic heart failure and reduced systolic function , an implantable cardioverter-defibrillator ( ICD )  improves the prognosis , but morbidity and mortality remain high . We attempted to identify the prognostic impact of Doppler echocardiography and QRS duration in such patients . We prospect ively enrolled 84 patients with chronic heart failure , an ICD , and impaired systolic function ( mean ejection fraction 29 + /- 10 % ) . Echocardiographic measurements included left ventricular dimensions/volumes , ejection fraction , mitral E/A ratio , deceleration time , and tissue Doppler analysis of mitral annular velocities ( S ' , E ' , A ' ) . A cardiac event ( death from pump failure or appropriate ICD therapy , i.e. , antitachycardia pacing/shock due to sustained ventricular tachycardia or ventricular fibrillation ) was defined as the study end point . During a follow-up of 373 + /- 254 days , 22 patients ( 26 % ) had an event ( death from pump failure , n = 7 ; patients who received an appropriate ICD therapy , n = 16 ) . In patients with an event , the QRS duration was longer ( 169 + /- 41 vs 146 + /- 37 ms , p = 0.023 ) , the mitral E/E ' ratio was higher ( 16.0 + /- 6.5 vs 12.8 + /- 5.9 , p = 0.044 ) , and a restrictive filling pattern was more frequent ( 44 % vs 9 % , p = 0.017 ) . Stepwise multivariate Cox regression analysis identified a restrictive filling pattern as the only independent predictor of an event ( hazard ratio 3.65 , 95 % confidence interval 1.54 to 8.64 , p = 0.003 ) . For patients with a restrictive filling pattern , the outcome was markedly poorer than that for patients with a nonrestrictive pattern ( event-free survival rate 38 % vs 72 % , p = 0.005 ) . In conclusion , in patients with chronic heart failure , an ICD , and systolic dysfunction , a restrictive filling pattern is an independent predictor of adverse cardiac events BACKGROUND The Coronary Artery Bypass Graft ( CABG ) Patch Trial tested the hypothesis that prophylactic insertion of an implantable cardioverter-defibrillator ( ICD )  improves survival rates after high-risk CABG . We compared group-specific perioperative morbidity and mortality rates . METHODS AND RESULTS Patients were r and omized intraoperatively to undergo CABG ( control subjects , n = 454 ) or CABG plus ICD implantation ( n = 446 ) . There were no significant differences between groups in the incidence of diabetes , ejection fraction < 0.25 , end-diastolic pressure , prior myocardial infa rct ion , or congestive heart failure . Cardiopulmonary bypass time averaged 106 minutes in control subjects and 127 minutes in the ICD group . At the inception of the trial , investigators were concerned that ICD therapy could increase surgical mortality rates or the incidence of shock , bleeding , congestive heart failure , arrhythmias , or deep sternal wound infection . Of these , only sternal wound infection was significantly more frequent in the ICD group ( 2.2 % versus 0.4 % , P < 0.05 ) . Also more common in the ICD group were infection at a wound or catheter site ( 12 % versus 6 % ) , urinary tract infection ( 4 % versus 1 % ) , pneumonitis ( 8 % versus 4 % ) , respiratory insufficiency ( 13 % versus 8 % ) , transient central nervous system deficit ( 6 % versus 2 % ) , and psychotic reaction ( 4 % versus 1 % ) . The all-cause death rate was 6.7 % in the ICD group and 4.6 % for control patients ( P = NS ) at the time of the last surgical death , postoperative day 48 . CONCLUSIONS Epicardial ICD insertion during CABG is associated with an increase in perioperative infection . Although reporting bias may have influenced the data , if ICD insertion is indicated in CABG patients , metachronous endocardial implantation should be considered BACKGROUND Patients with left ventricular dysfunction who undergo coronary artery bypass graft ( CABG ) surgery  frequently have late sudden cardiac death . The CABG Patch Trial is a prospect i ve , r and omized , multicenter clinical trial that r and omized patients at high risk at the completion of CABG surgery to implantation of an epicardial implantable cardioverter defibrillator ( ICD ) or to no antiarrhythmic treatment .  The trial was design ed to determine whether prophylactic implantation of an ICD at the time of CABG surgery would result in a lower total mortality in long-term follow-up . METHODS Patients undergoing CABG surgery were eligible for the trial if they were younger than 80 years , had a left ventricular ejection fraction less than 0.36 , and had an abnormal signal averaged electrocardiogram . Patients with a history of sustained ventricular tachycardia or ventricular fibrillation were excluded from the trial . All patients were scheduled to undergo follow-up at 3-month intervals until 42 months after surgery . RESULTS R and omization of patients in the trial ended in February 1996 . During the recruitment period 71,855 patients were screened , 1,422 were eligible , 1,055 were enrolled ( signed consent forms ) , and 900 patients ( 76 % of eligible patients ) were r and omized . The mean age of the 446 patients in the ICD group was 64 years versus 63 years for the 454 patients in the control group . A total of 87 % of the participants in the ICD group were men versus 82 % in the control group ( p = NS ) . Most of the patients had a history of hypertension ( 55 % ) , smoking ( 78 % ) , and hypercholesterolemia ( 54 % ) . Half of the patients had clinical heart failure , and the mean ejection fraction for both patient groups was 0.27 + /- 0.06 . No difference was seen in the history of myocardial infa rct ion ( 83 % ) , congestive heart failure ( 50 % ) , or atrial ( 11 % ) or ventricular ( 17 % ) arrhythmias between the two groups . Major clinical characteristics ( age , sex , number of previous infa rct ions , incidence of heart failure , and mean left ventricular ejection fraction ) were almost identical to those found in another ICD primary prevention trial , the Multicenter Automatic Defibrillator Implantation Trial ( MADIT ) . CONCLUSIONS A high risk sample of patients was enrolled in The CABG Patch Trial , as shown by examination of their baseline characteristics Background —Cardiac resynchronization ( CRT ) prolongs survival in patients with systolic heart failure and QRS prolongation . However , most trials excluded patients with permanent atrial fibrillation . Methods and Results —The Resynchronization for Ambulatory Heart Failure Trial ( RAFT ) r and omized patients to an implantable cardioverter defibrillator ( ICD ) or ICD+CRT , stratified by the presence of permanent atrial fibrillation . Patients with permanent atrial fibrillation were r and omized to CRT-ICD ( n=114 ) or ICD ( n=115 ) . Patients receiving a CRT-ICD were similar to those receiving an ICD  : age ( 71.6±7.3 versus 70.4±7.7 years ) , left ventricular ejection fraction ( 22.9±5.3 % versus 22.3±5.1 % ) , and QRS duration ( 151.0±23.6 versus 153.4±24.7 ms ) . There was no difference in the primary outcome of death or heart failure hospitalization between those assigned to CRT-ICD versus ICD ( hazard ratio , 0.96 ; 95 % CI , 0.65–1.41 ; P=0.82 ) . Cardiovascular death was similar between treatment arms ( hazard ratio , 0.97 ; 95 % CI , 0.55–1.71 ; P=0.91 ) ; however , there was a trend for fewer heart failure hospitalizations with CRT-ICD ( hazard ratio , 0.58 ; 95 % CI , 0.38–1.01 ; P=0.052 ) . The change in 6-minute hall walk duration between baseline and 12 months was not different between treatment arms ( CRT-ICD : 19±84 m versus ICD : 16±76 m ; P=0.88 ) . Patients treated with CRT-ICD showed a trend for a greater improvement in Minnesota Living with Heart Failure score between baseline and 6 months ( CRT-ICD : 41±21 to 31±21 ; ICD : 33±20 to 28±20 ; P=0.057 ) . Conclusions — Patients with permanent atrial fibrillation who are otherwise CRT c and i date s appear to gain minimal benefit from CRT-ICD compared with a st and ard ICD . Clinical Trial Registration —URL : http://www . clinical trials.gov . Unique identifier : NCT00251251 CONTEXT Implantable cardioverter defibrillator ( ICD ) therapy with backup ventricular pacing increases survival in patients with life-threatening ventricular arrhythmias . Most currently implanted ICD devices provide dual-chamber pacing therapy . The most common comorbid cause for mortality in this population is congestive heart failure . OBJECTIVE To determine the efficacy of dual-chamber pacing compared with backup ventricular pacing in patients with st and ard indications for ICD implantation but without indications for antibradycardia pacing . DESIGN The Dual Chamber and VVI Implantable Defibrillator ( DAVID ) Trial , a single-blind , parallel-group , r and omized clinical trial . SETTING AND PARTICIPANTS A total of 506 patients with indications for ICD therapy were enrolled between October 2000 and September 2002 at 37 US centers . All patients had a left ventricular ejection fraction ( LVEF ) of 40 % or less , no indication for antibradycardia pacemaker therapy , and no persistent atrial arrhythmias . INTERVENTIONS All patients had an ICD with dual-chamber , rate-responsive pacing capability implanted . Patients were r and omly assigned to have the ICDs programmed to ventricular backup pacing at 40/min ( VVI-40 ; n = 256 ) or dual-chamber rate-responsive pacing at 70/min ( DDDR-70 ; n = 250 ) . Maximal tolerated medical therapy for left ventricular dysfunction , including angiotensin-converting enzyme inhibitors and beta-blockers , was prescribed to all patients . MAIN OUTCOME MEASURE Composite end point of time to death or first hospitalization for congestive heart failure . RESULTS One-year survival free of the composite end point was 83.9 % for patients treated with VVI-40 compared with 73.3 % for patients treated with DDDR-70 ( relative hazard , 1.61 ; 95 % confidence interval [ CI ] , 1.06 - 2.44 ) . The components of the composite end point , mortality of 6.5 % for VVI-40 vs 10.1 % for DDDR-70 ( relative hazard , 1.61 ; 95 % CI , 0.84 - 3.09 ) and hospitalization for congestive heart failure of 13.3 % for VVI-40 vs 22.6 % for DDDR-70 ( relative hazard , 1.54 ; 95 % CI , 0.97 - 2.46 ) , also trended in favor of VVI-40 programming . CONCLUSION For patients with st and ard indications for ICD therapy , no indication for cardiac pacing , and an LVEF of 40 % or less , dual-chamber pacing offers no clinical advantage over ventricular backup pacing and may be detrimental by increasing the combined end point of death or hospitalization for heart failure
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 .