Sinus tachycardia is associated with impaired exercise tolerance following heart transplantation

Abstract

Background: Sinus tachycardia often presents in heart transplantation (HTx) recipients, but data on its effect on exercise performance are limited.

Methods: Based on mean heart rate (HR) value 3 months after HTx, 181 patients transplanted from 2006 to 2015 at University of Nebraska Medical Center were divided into two groups: (i) HR<95 beats/min (bpm, n=93); and (ii) HR≥95 bpm (n=88). Cardiopulmonary exercise testing (CPET) was performed 1 year after HTx.

Results: Mean HR at 3 months post-HTx was 94±11 bpm and did not change significantly at 1 year post-HTx (96±11 bpm, P=.13). HR≥95 bpm at 3 months was associated with younger donor age (OR 1.1; CI 1.0-1.1, P=.02), female donors (OR -2.4; CI 1.16-5.24 P=.02), and lack of donors' heavy alcohol use (OR -0.43; CI 0.17-0.61; P=.04). HR≥95 bpm at 3 months post-HTx was independently associated with decreased exercise capacity in metabolic equivalent (P=.008), reduced peak VO₂ (P=.006), and percent of predicted peak VO₂ (P=.002) during CPET.

Conclusions: HR≥95 at 3 months following HTx is associated with reduced exercise tolerance in stable HTx recipients. Medical HR reduction after HTx could improve exercise performance after HTx and merits further investigation.

Keywords: complication; heart (allograft) function/dysfunction; quality of life.