Cardiac contractility modulation for heart failure: a meta-analysis of randomized controlled trials.
BACKGROUND
Cardiac contractility modulation (CCM) emerges as a promising device treatment for heart failure (HF). This meta-analysis aimed to systematically review the latest available randomized evidence on the effectiveness and safety of CCM in HF.


METHODS
The Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE were searched in November 2011 to identify eligible randomized controlled trials comparing CCM with sham treatment or usual care. Primary outcomes of interest were all-cause mortality, all-cause hospitalizations, and adverse effects. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated for dichotomous data using a random-effects model.


RESULTS
Three studies enrolling 641 participants were included. Pooled analysis showed that, compared to control, CCM did not significantly improve all-cause mortality (n = 629, RR 1.19, 95% CI 0.50-2.86, P = 0.69), nor was there a favorable effect in all-cause hospitalizations. No increase in adverse effects with CCM was observed.


CONCLUSIONS
Meta-analysis of data from small randomized trials suggests that CCM, although with no clear benefits in improving clinical outcomes, is not associated with worsening prognosis. Large, well-designed trials are needed to confirm its role in HF patients for whom cardiac resynchronization therapy is contraindicated or unsuccessful.
Institute of Vascular Medicine, Li Ka Shing Institute of Health Sciences, S.H. Ho Cardiovascular Disease and Stroke Centre, Heart Education And Research Training (HEART) Centre and Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
Joey S W
JS
Kwong
John E
JE
Sanderson
Cheuk-Man
CM
Yu
D002304:Cardiac Pacing, Artificial / Q000379:methods* / Q000401:mortality*; D006333:Heart Failure / Q000401:mortality* / Q000517:prevention & control*; D006760:Hospitalization; D006801:Humans; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome