Impact of implantable defibrillators and resynchronization therapy on outcome in patients with left ventricular dysfunction--a meta-analysis.
BACKGROUND
The clinical benefits of cardiac resynchronization therapy (CRT) and primary prophylactic implantable cardioverter defibrillator (ICD) in patients with left ventricular systolic dysfunction (LVSD) are debated.


OBJECTIVE
To evaluate by a meta-analysis the effect of CRT and prophylactic ICD therapy in patients with LVSD.


METHODS
Eligible trials evaluating the effect of CRT vs. no-CRT, ICD vs. no-ICD and adding ICD to CRT vs. no-ICD were selected and meta-analyzed. The outcomes were: all cause mortality, cardiac mortality, hospitalization for heart failure and change in exercise tolerance and New York Heart Association class.


RESULTS
Implantation of CRT reduced all cause mortality odds ratio (OR) = 0.73 (0.60-0.89) p = 0.002 and hospitalization for heart failure OR = 0.60 (0.45, 0.80) p = 0.001, increased peak oxygen consumption by 1.77 (0.32-3.22) ml/kg/min p = 0.017 and improved New York Heart Association class by at least one class with OR = 1.52 (1.30, 1.77) p < 0.0001. Implantation of ICD reduced all-cause mortality OR = 0.75 (0.59-0.96) p = 0.025 and cardiac mortality OR = 0.63 (0.48, 0.82) p = 0.001. Adding ICD to CRT reduced all cause mortality OR = 0.69 (0.53-0.91) p = 0.008.


CONCLUSIONS
Selective patients with LVSD benefit from CRT, ICD or both. Further investigations are necessary to clarify which patients benefit most from a single or combined device implantation.
Abdulla
Jawdat
J
Department of Cardiology, Gentofte University Hospital, Copenhagen, Denmark. ja@heart.dk
Haarbo
Jens
J
Køber
Lars
L
Torp-Pedersen
Christian
C
D017147:Defibrillators, Implantable; D006801:Humans; D010138:Pacemaker, Artificial; D018487:Ventricular Dysfunction, Left / Q000401:mortality* / Q000628:therapy*