Effect of biventricular pacing on symptoms and cardiac remodelling in patients with end‐stage hypertrophic cardiomyopathy

Abstract

Background: Biventricular (BiV) pacing is an established therapy for heart failure in ischaemic and dilated cardiomyopathy. Its effects in endstage hypertrophic cardiomyopathy (HCM) are unknown. Aims: To assess the potential benefits of BiV pacing in patients with symptomatic end-stage HCM. Methods: Twenty patients with non-obstructive HCM (12 male, mean age 57 ± 13 years), left bundle branch block and symptoms of heart failure refractory to medical therapy underwent implantation of a BiV device. NYHA class, echocardiographic parameters and exercise capacity were assessed before and after implantation. Results: At a mean follow-up of 13 ± 6 months, an improvement of at least one NYHA class was reported in 8 (40%) patients. A clinical response was associated with an increase in ejection fraction (from 41 ± 14% to 50 ± 12%, p = 0.009), and reductions in left ventricular enddiastolic diameter (from 57 ± 6 mm to 52 ± 7 mm, p = 0.031) and left atrial diameter (from 65 ± 8 mm to 57 ± 6 mm, p = 0.005). Percentage predicted peak oxygen consumption was unchanged in responders but significantly declined in non-responders (p = 0.029). Conclusions: BiV pacing improved heart failure symptoms in a significant proportion of patients with end-stage HCM. Symptomatic improvement was associated with reverse remodelling of the left atrium and ventricle.

Disease Pathways and Novel Therapeutic Targets in Hypertrophic Cardiomyopathy

“…An existing study of end-stage HCM, in which BiVP promoted LV reverse-remodeling, and improved symptoms provide a rationale for further studies that are ongoing (NCT00504647). 103 …”

2011 ACCF/AHA Guideline for the Diagnosis and Treatment of Hypertrophic Cardiomyopathy

“…There is a paucity of published data on the use of cardiac resynchronization therapy devices in patients with HCM and end-stage heart failure. 421 A number of large cohort studies from the United States indicate that HCM is the most common cardiovascular cause of SCD in young athletes, accounting for about one third of these events. 58,59,425,427 The American College of Cardiology Bethesda Conference No.…”

45-year-old man with hypertrophic cardiomyopathy after alcohol ablation, progression to dilated cardiomyopathy (RCD code: III‑1B.8a)

“…Our patient had ventricular arrhythmias with an episode of non-sustained VT registered during the Holter monitoring ECG and therefore he was qualified for ICD. Perhaps, if he had had ECG evidence of electrical dyssynchrony (wide and disturbed QRS), he should have been probably qualified also for cardiac resynchronization therapy (CRT) as it was proved to have a good effect on heart failure symptoms and can slow or even reverse LV remodeling [9]. However, our patient's QRS duration was only 110 ms without typical left bundle branch block morphology and as a result he was not a "classic" candidate for CRT.…”