Evolving Indications, Challenges, and Advances in Cardiac Resynchronization Therapy for Heart Failure.

Abstract

Cardiac resynchronization therapy (CRT) via biventricular pacing has markedly improved heart failure outcomes over the past two decades. However, some patients show no clinical improvement or evidence of reverse remodeling following device implantation. Challenges include suboptimal patient selection, limitations in the characterization of conduction disease (especially nonspecific interventricular conduction delays), procedural constraints, inappropriate device programming, and delayed referral. Moreover, there remains no formal consensus on evaluating and characterizing CRT efficacy. Underutilization persists among women and minoritized racial and ethnic groups. Targeted research addressing unmet needs has led to evolving guideline indications. Novel electrocardiographic and imaging techniques are continually being developed to improve patient selection and alternate pacing strategies have emerged. Conduction system pacing may allow for a more physiologic approach to CRT. Observational studies and small clinical trials have shown comparable or superior efficacy of conduction system pacing over traditional biventricular pacing; however, more studies are needed. LAY SUMMARY: Cardiac resynchronization therapy via biventricular pacing has transformed heart failure management over the past two decades. This review examines persistent challenges in clinical practice and evolving guideline recommendations. Key issues, including refining patient selection, better characterizing conduction abnormalities, and optimizing device programming, were highlighted. Emerging evidence suggests conduction system pacing as a physiologic alternative to biventricular pacing, with early studies showing promising outcomes. However, rigorous clinical trials are needed to confirm these findings and guide future practice. Advancing CRT necessitates continued innovation and strategies to improve equity and access across diverse populations.