Leadless left ventricular endocardial pacing for cardiac resynchronization therapy: A systematic review and meta-analysis

BACKGROUND Leadless left ventricular (LV) endocardial pacing to achieve cardiac resynchronization therapy (CRT) is a novel procedure for treatment of patients with dyssynchronous heart failure. Current evidence is limited to observational studies with small patient numbers. OBJECTIVE The purpose of this systematic review and meta-analysis was to assess the safety and efficacy of leadless LV endocardial pacing. METHODS A literature search was conducted through PubMed, EMBASE, and Cochrane databases. Mean differences (MDs) in New York Heart Association (NYHA) functional class and LV ejection fraction (LVEF) from baseline to 6 months postprocedure were combined using a random effects model. Heterogeneity was evaluated using the Cochrane Q test, I-2, meta-regression, and sensitivity analysis. Funnel plots were constructed to detect publication bias. RESULTS Five studies with 181 patients were included in the final analysis. Procedural success rate was 90.6%. Clinical response rate was 63%, with mean improvement in NYHA functional class of 0.43 (MD-0.43; 95% confidence interval [CI] -0.76 to -0.1; P < .01), with high heterogeneity (P<.001; I-2 - 81.1%). There was a mean increase in LVEF of 6.3% (MD 6.3; 95% CI 4.35-8.19; P<.001, with low heterogeneity (P=0.84; I-2, 0.001%). The echocardiographic response rate was 54%. Procedure-related complication and mortality rates were 23.8% and 2.8%, respectively. CONCLUSION The efficacy of leadless LV endocardial pacing for CRT supports its use as a second-line therapy in patients in whom standard CRT is not possible or has been ineffective. Improvements in safety profile will facilitate widespread uptake in the treatment of these patients.

Automated summary

This systematic review and meta-analysis assesses the safety and efficacy of leadless left ventricular endocardial pacing for cardiac resynchronization therapy (CRT) in patients with dyssynchronous heart failure. The results indicate that leadless LV endocardial pacing is effective as a second-line therapy for patients who are unable to undergo or are unresponsive to standard CRT. However, procedure-related complications and mortality rates are relatively high, highlighting the need for further improvement in safety.