Prognostic Significance of Heart Rate and its Long-term Trend in Cardiac Transplant Patients.

INTRODUCTION AND OBJECTIVES The aim of the present study was to examine the prognostic significance of heart rate and its trend in heart transplantation. METHODS This observational study enrolled 170 patients who received a bicaval heart transplant between 1995 and 2005; all were in sinus rhythm. The resting heart rate was determined via electrocardiography at the end of the first posttransplant year and annually until the tenth year. Cox analysis was used to evaluate the incidence of adverse events with a mean (standard deviation) follow-up of 8.9 (3.1) years. The primary study end point was the composite outcome of death or graft dysfunction. RESULTS The resting heart rate at the end of the first posttransplant year was an independent predictor of the primary composite end point (hazard ratio=1.054; 95% confidence interval, 1.028-1.080; P<.001) and was significantly associated with total mortality (hazard ratio=1.058; 95% confidence interval, 1.030-1.087; P<.001) and mortality from cardiac causes (hazard ratio=1.069; 95% confidence interval, 1.026-1.113; P=.001), but not with graft dysfunction (hazard ratio=1.028; 95% confidence interval, 0.989-1.069; P=.161). For patients with a heart rate ≥ 105 or<90 bpm vs those with 90-104 bpm, the hazard ratios of the primary end point were 2.233 (95% confidence interval, 1.250-3.989; P=.007) and 0.380 (95% confidence interval, 0.161-0.895; P=.027), respectively. Heart rate tended to decrease in the first 10 years after transplantation (P=.001). Patients with a net increase in heart rate during follow-up showed a higher incidence of adverse events. CONCLUSIONS An elevated heart rate is an adverse prognostic marker after heart transplantation.