***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: AIMS Whilst the CArdiac REsynchronization in Heart Failure ( CARE-HF ) trial has shown that cardiac resynchronization therapy ( CRT ) leads to reduced morbidity and mortality , the cost-effectiveness of this therapy remains uncertain . The aim of this study was to evaluate the incremental cost per quality adjusted life year ( QALY ) gained and incremental cost per life year gained of CRT plus medical therapy compared to medical therapy alone . METHODS AND RESULTS This prospect i ve analysis based on intention to treat data from all patients enrolled in the CARE-HF trial at 82 clinical centres in 12 European countries . A total of 813 patients with New York Heart Association class III or IV heart failure due to left ventricular systolic dysfunction and cardiac dyssynchrony were r and omized to CRT plus medical therapy ( n = 409 ) vs. medical therapy alone  ( n = 404 ) . During a mean follow-up of 29.4 months CRT was associated with increased costs ( 4316 , 95 % CI : 1327 - 7485 ) , survival ( 0.10 years , 95 % CI : -0.01 - 0.21 ) , and QALYs ( 0.22 , 95 % CI : 0.13 - 0.32 ) . The incremental cost-effectiveness ratio was 19 319 per QALY gained ( 95 % CI : 5482 - 45 402 ) and 43 596 per life-year gained ( 95 % CI : -146 236 - 223 849 ) . These results were sensitive to the costs of the device , procedure , and hospitalization . CONCLUSION Treatment with CRT appears cost-effective at the notional willingness to pay threshold of 29 400 ( 20,000 pounds sterlings ) per QALY gained OBJECTIVES The evaluation of the risk of recurring heart failure events ( HFEs ) was a pre-specified sub study of MADIT-CRT ( Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy ) . BACKGROUND There are limited data regarding the effect of cardiac resynchronization therapy with a defibrillator ( CRT-D ) on the occurrence of recurring heart failure episodes after a first post-implantation HFE . METHODS Data with regard to recurring HFEs were prospect ively collected for all 1,820 MADIT-CRT participants . The CRT-D versus defibrillator-only risk for nonfatal first- and subsequent-HFEs was assessed by Cox proportional hazards and And ersen-Gill proportional intensity regression modeling , respectively , in efficacy analyses recognizing active device-type during follow-up . RESULTS Multivariate analysis showed that CRT-D was associated with a significant reduction in the risk of a first HFE ( hazard ratio [ HR ] : 0.54 , 95 % confidence interval [ CI ] : 0.44 to 0.67 , p < 0.001 ) and with a similar magnitude of reduction in the risk of HFEs subsequent to a first post-enrollment event ( HR : 0.62 , 95 % CI : 0.45 to 0.85 , p = 0.003 ) . The benefit of CRT-D for the prevention of first and subsequent HFEs was pronounced among patients with left bundle branch block ( HR : 0.38 , 95 % CI : 0.29 to 0.49 , p < 0.001 ; and HR : 0.50 , 95 % CI : 0.33 to 0.76 , p = 0.001 , respectively ) and nonsignificant in non-left bundle branch block patients ( HR : 1.12 , 95 % CI : 0.77 to 1.64 , p = 0.55 ; and HR : 0.99 , 95 % CI : 0.58 to 1.69 , p = 0.96 , respectively ; p values for interaction : p < 0.001 and p = 0.06 , respectively ) . The occurrences of first and second HFEs were associated with 7- and nearly 19-fold respective increases in the risk of subsequent mortality . CONCLUSIONS In the MADIT-CRT trial , the benefit of cardiac resynchronization therapy for the reduction in recurring HFEs was maintained after the occurrence of a first post-enrollment event . The occurrence of HFEs greatly increased the risk of death . ( Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy ; NCT00180271 ) BACKGROUND We conducted a prospect i ve , multicenter , r and omized comparison of implantable cardioverter-defibrillator ( ICD ) versus antiarrhythmic drug therapy in survivors of cardiac arrest secondary to documented ventricular arrhythmias . METHODS AND RESULTS From 1987 , eligible patients were r and omized to an ICD , amiodarone , propafenone , or metoprolol ( ICD versus antiarrhythmic agents r and omization ratio 1:3 ) . Assignment to propafenone was discontinued in March 1992 , after an interim analysis conducted in 58 patients showed a 61 % higher all-cause mortality rate than in 61 ICD patients during a follow-up of 11.3 months . The study continued to recruit 288 patients in the remaining 3 study groups ; of these , 99 were assigned to ICDs , 92 to amiodarone , and 97 to metoprolol . The primary end point was all-cause mortality . The study was terminated in March 1998 , when all patients had concluded a minimum 2-year follow-up . Over a mean follow-up of 57+/-34 months , the crude death rates were 36.4 % ( 95 % CI 26.9 % to 46.6 % ) in the ICD and 44.4 % ( 95 % CI 37.2 % to 51.8 % ) in the amiodarone/metoprolol arm . Overall survival was higher , though not significantly , in patients assigned to ICD than in those assigned to drug therapy ( 1-sided P=0.081 , hazard ratio 0.766 , [ 97.5 % CI upper bound 1.112 ] ) . In ICD patients , the percent reductions in all-cause mortality were 41.9 % , 39.3 % , 28 . 4 % , 27.7 % , 22.8 % , 11.4 % , 9.1 % , 10.6 % , and 24.7 % at years 1 to 9 of follow-up . CONCLUSIONS During long-term follow-up of cardiac arrest survivors , therapy with an ICD is associated with a 23 % ( nonsignificant ) reduction of all-cause mortality rates when compared with treatment with amiodarone/metoprolol . The benefit of ICD therapy is more evident during the first 5 years after the index event Background —Implantable cardioverter defibrillator ( ICD ) use reduces mortality in patients with serious ventricular arrhythmias compared with antiarrhythmic drug ( AAD ) use . However , the relative impact of these therapies on self-perceived quality of life ( QoL ) is unknown . Methods and Results —Three self-administered instruments were used to measure generic and disease-specific QoL in  Antiarrhythmics  Versus  Implantable Defibrillators  trial participants . Generalized linear models were used to assess the relationships between self-perceived QoL and treatment ( AAD versus ICD ) and adverse symptoms and ICD shocks . To minimize the impact of missing data , only patients surviving 1 year were included in the primary analyses . Baseline characteristics among QoL participants ( n=905 ) and non participants ( n=111 ) were similar , but participants who survived 1 year ( n=800 ) were healthier at baseline than nonsurvivors ( n=105 ) . Of the 800 patients in the primary analysis , characteristics of those r and omized to AAD ( n=384 ) versus ICD ( n=416 ) were similar . Overall , ICD and AAD use were associated with similar alterations in QoL. The development of sporadic shocks and adverse symptoms were each associated with reduced physical functioning and mental well-being and increased concerns among ICD recipients , whereas development of adverse symptoms was associated with reduced physical functioning and increased concerns among AAD recipients . Conclusions —ICD and AAD therapy are associated with similar alterations in self-perceived QoL over 1-year follow-up . Adverse symptoms were associated with reduced self-perceived QoL in both groups , and sporadic shocks were associated with reduced QoL in ICD recipients BACKGROUND To date , the implantable cardioverter-defibrillator ( ICD ) has been shown to be effective for primary prevention of sudden cardiac death only in selected groups of patients in the chronic phase after myocardial infa rct ion . METHODS AND RESULTS The Immediate Risk-Stratification Improves Survival ( IRIS ) Study compares ICD therapy with no ICD therapy in selected high risk patients early after myocardial infa rct ion . Special emphasis is placed on optimal acute and long term medical therapy in all patients including  metoprolol CR/ZOK . The hypothesis is tested that use of the ICD reduces overall mortality . For that purpose , consecutive acute ST elevation or non-ST elevation myocardial infa rct ion patients are collected in a registry . From this denominator , patients are screened , and enrolled early after myocardial infa rct ion ( day 5 to day 31 ) if they exhibit both a reduced left ventricular ejection fraction < or = 40 % and a heart rate > or = 100 bpm on the first available electrocardiogram ( criterion I ) , or non-sustained ventricular tachycardia at a rate > or = 150 bpm during Holter ( criterion II ) . CONCLUSIONS IRIS is a large scale prospect i ve , r and omized trial to evaluate the benefit of ICD therapy for reduction of total mortality in patients considered at high risk of sudden death early after acute myocardial infa rct ion BACKGROUND Although pharmacological therapy has ameliorated symptoms and improved the survival of patients with chronic heart failure ( CHF ) , this chronic syndrome remains a progressive disease causing incremental morbidity and early mortality . A new therapy for the treatment of CHF should ideally decrease mortality , alleviate symptoms , and improve functional capacity . A growing body of evidence suggests that the use of implantable devices to resynchronize ventricular contraction may be a beneficial adjunct in the treatment of CHF . METHODS The Comparison of Medical Therapy , Pacing , and Defibrillation in Chronic Heart Failure ( COMPANION ) trial is a r and omized , open-label , 3-arm study of patients in New York Heart Association class III or IV with an ejection fraction of 35 % or less and a QRS duration of 120 milliseconds or less . The COMPANION study objectives are to determine whether optimal pharmacological therapy used with ( 1 ) ventricular resynchronization therapy alone or ( 2 ) ventricular resynchronization therapy combined with cardioverter-defibrillator capability is superior to optimal pharmacological therapy alone in reducing combined all-cause mortality and hospitalizations ; reducing cardiac morbidity ; improving functional capacity , cardiac performance , and quality of life ; and increasing total survival OBJECTIVES This study analyzed the causes of death in the  Antiarrhythmics Versus Implantable Defibrillators ( AVID ) Trial . BACKGROUND Both implantable cardioverter-defibrillators ( ICDs ) and antiarrhythmic drugs ( AADs ) are used as mainstays of treatment for life-threatening ventricular arrhythmias in patients who have survived either ventricular fibrillation or sustained ventricular tachycardia with hemodynamic compromise and serious symptoms . The AVID Trial compared the effectiveness of these two therapies . Survival was better with the ICD . Assessment of the cause of death should help to determine the mechanism of improvement in survival with the ICD . METHODS Of 1,016 patients enrolled in the AVID Trial , 202 patients died . The mode of death was determined by the unblinded Principal Investigator and independently by an Events Committee , which review ed material s meticulously blinded with respect to treatment . Deaths were classified as cardiac or noncardiac . Cardiac deaths were further classified as arrhythmic or nonarrhythmic , and causes of noncardiac death were identified . RESULTS Deaths were more frequent in patients treated with an AAD ( n = 122 ) , compared with patients treated with the ICD ( n = 80 ) , unadjusted p < 0.001 , p = 0.012 adjusted for sequential monitoring . In AVID , 157 deaths were cardiac , and 79 were arrhythmic . The major effect of the ICD was to prevent arrhythmic death ( AAD = 55 , ICD = 24 , nominal unadjusted p < 0.001 ) . Nonarrhythmic cardiac deaths were equal ( AAD = 39 , ICD = 39 ) . Patients treated with an AAD had a slightly greater incidence of noncardiac deaths ( 28 vs. 17 , p = 0.053 ) , primarily due to pulmonary and renal causes . CONCLUSIONS The ICD is more effective than an AAD in reducing arrhythmic cardiac death , while nonarrhythmic cardiac death is unchanged . Of note , apparent arrhythmic death still seems to constitute 38 % of all cardiac deaths despite 
    Output:
    
A reduction in SCD but not all-cause mortality was found in people  with recent MI .
CRT-P and CRT-D  reduced mortality and HF hospitalisations , and improved other outcomes , in people with HF as a result of LVSD and cardiac dyssynchrony when compared with OPT .
The rate of SCD was lower with CRT-D than with CRT-P but other outcomes were similar .
In people with both conditions , CRT-D reduced the risk of all-cause mortality and HF hospitalisation , and improved other outcomes , compared with ICDs .