What is the clinical evidence from this study?

Study design: Cohort. Population: End-stage hypertrophic cardiomyopathy (n=20). Intervention: Biventricular pacing. Primary outcome: Improvement of at least one NYHA class.

April 11, 2008Open Access

Effect of Biventricular Pacing on Symptoms and Cardiac Remodelling in Patients with End-Stage Hypertrophic Cardiomyopathy

Key Result

Biventricular pacing improved heart failure symptoms by at least one NYHA class in 40% of patients with end-stage hypertrophic cardiomyopathy, and increased ejection fraction (p=0.009).

Study Design

Type

Cohort (n=20)

Structured PICO

Does biventricular pacing improve symptoms and cardiac remodelling in patients with end-stage hypertrophic cardiomyopathy?

Population

20 patients with non-obstructive end-stage hypertrophic cardiomyopathy (HCM), left bundle branch block, and symptoms of heart failure refractory to medical therapy, mean age 57±13 years, 12 male.

Intervention

Implantation of a biventricular (BiV) pacing device

Outcome

Change in NYHA class, echocardiographic parameters, and exercise capacity before and after implantationpatient reported

Biventricular pacing may improve heart failure symptoms and induce reverse cardiac remodelling in a subset of patients with end-stage hypertrophic cardiomyopathy and left bundle branch block.

Abstract

Abstract Background Biventricular (BiV) pacing is an established therapy for heart failure in ischaemic and dilated cardiomyopathy. Its effects in end-stage 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 end-diastolic 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.