Cardiac resynchronization therapy with a defibrillator reduced the risk of heart failure or death by 34% in ischemic (P=0.001) and 44% in non-ischemic (P=0.002) cardiomyopathy compared to ICD alone.
RCT (n=1,820)
Does CRT-D reduce the risk of heart failure or death compared to ICD therapy in mildly symptomatic patients with ischemic and non-ischemic cardiomyopathy?
CRT-D provides significant clinical benefit in both ischemic and non-ischemic mildly symptomatic cardiomyopathy, though non-ischemic patients show greater echocardiographic reverse remodeling.
Effect estimate: Risk reduction 34% (ICM) and 44% (non-ICM)
p-value: p=0.001 (ICM), 0.002 (non-ICM)
AIMS: There are no data regarding the differential response to cardiac resynchronization therapy with defibrillator (CRT-D) by the aetiology of cardiomyopathy in mildly symptomatic patients. We evaluated the outcome of patients enrolled in MADIT-CRT by ischaemic and non-ischaemic aetiology of cardiomyopathy (ICM and non-ICM, respectively). METHODS AND RESULTS: The clinical response to CRT-D was assessed among ICM (n = 1046) and non-ICM (n = 774) patients enrolled in MADIT-CRT during an average follow-up of 2.4 years, and echocardiographic response was assessed at 1 year. Cardiac resynchronization therapy with defibrillator vs. ICD therapy was associated with respective 34% (P = 0.001) and 44% (P = 0.002) reductions in the risk of heart failure or death among ICM and non-ICM patients (P for interaction = 0.455). In the ICM group, CRT-D was associated with mean (±SD) 29 ± 14% and 18 ± 10% reductions in left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV), respectively. In the non-ICM group, CRT-D was associated with significantly greater volume reductions compared with the ICM group 37 ± 16% and 24 ± 12% reductions in LVESV and LVEDV, respectively (P < 0.001 for all). Risk subsets in the ICM group that showed a favourable clinical response to CRT-D included patients with QRS ≥150 ms, systolic blood pressure <115 mmHg, and left bundle branch block (LBBB), whereas in the non-ICM group females, patients with diabetes mellitus, and LBBB, displayed a favourable clinical response. CONCLUSION: Mildly symptomatic ICM and non-ICM patients show significant differences in the echocardiographic response to CRT-D and in the clinical benefit within risk subsets suggesting that risk assessment for CRT-D in this population should be aetiology-specific.
Barsheshet et al. (Fri,) conducted a rct in Mildly symptomatic ischaemic and non-ischaemic cardiomyopathy (n=1,820). Cardiac resynchronization therapy with defibrillator (CRT-D) vs. ICD therapy was evaluated on Heart failure or death (Risk reduction 34% (ICM) and 44% (non-ICM), p=0.001 (ICM), 0.002 (non-ICM)). Cardiac resynchronization therapy with a defibrillator reduced the risk of heart failure or death by 34% in ischemic (P=0.001) and 44% in non-ischemic (P=0.002) cardiomyopathy compared to ICD alone.