Treatment of cardiac resynchronization therapy non-responders: current approaches and new frontiers

ABSTRACT

Introduction

Cardiac resynchronization therapy (CRT) has developed into a very effective technology for patients with decreased systolic function and has substantially improved patients’ clinical course. However, non-responsiveness to CRT, described as lack of reverse cardiac chamber remodeling, leading to lack to improve symptoms, heart failure hospitalizations or mortality, is common, rather unpredictable, and not fully understood.

Areas covered

This article aims to discuss key factors that are impacting CRT response, from patient selection to LV lead position, to structured follow-up in CRT clinics. Secondly, common causes and interventions for CRT non-responsiveness are discussed. Next, insight is given into technologies representing new and feasible interventions as well as pacing strategies in this group of patients that remain challenging to treat. Finally, an outlook is given into future scientific development.

Expert opinion

Despite the progress that has been made, CRT non-response remains a significant and complex problem. Patient management in interdisciplinary teams including heart failure, imaging, and cardiac arrhythmia experts appears critical as complexity is increasing and CRT non-response often is a multifactorial problem. This will allow optimization of medical therapy, and the use of new integrated sensor technologies and telemedicine to ultimately optimize outcomes for all patients in need of CRT.

KEYWORDS:

• Cardiomyopathy
• cardiac resynchronization therapy
• device optimization
• future pacing technologies

Article highlights

• Cardiac resynchronization therapy has become a technology that has significantly improved outcomes of symptomatic heart failure patients with systolic dysfunction and significant cardiac conduction defect (QRS width ≥150 ms).

• CRT non-response remains a common problem in about 30–40% of patients.

• CRT non-response is multifactorial, involving several factors such as patient selection, lead implantation, and device programming.

• Optimization is complex and requires a multidisciplinary approach involving heart failure experts, imaging experts, and cardiac electrophysiologists to optimize medical therapy and device settings.

• Several new pacing strategies, such as different types of conduction system pacing, are being evaluated in these patients, toward the goal of continuously increasing the proportion of patients responding to CRT.

Declaration of interest

H. Immo Lehmann has received funding from the LaDue Fellowship at Harvard Medical School. Jagmeet P. Singh is a consultant to Abbott Inc, Biotronik Inc, Boston Scientific, Cardiologs Inc, CVRx Inc, EBR Inc, Impulse Dynamics, Implicity Inc, Medtronic Inc, Microport Inc., New Century Health, and Sanofi Inc. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewers disclosure

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Additional information

Funding

This paper was not funded.