Chronotropic Incompetence May Impact Exercise Capacity in Patients Supported by Left Ventricular Assist Device

• Published in: The Journal of heart and lung transplantation Vol. 32; no. 4; p. S93
• Main Authors: Garan, A.R, Nahumi, N, Han, J, Colombo, P, Yuzefpolskaya, M, Te-Frey, R, Takayama, H, Naka, Y, Uriel, N, Jorde, U.P
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.04.2013
• Subjects: Surgery
• ISSN: 1053-2498; 1557-3117
• DOI: 10.1016/j.healun.2013.01.999

Purpose Chronotropic incompetence (CI) is common in advanced heart failure (HF) patients. However, its prevalence and significance in patients with a left ventricular assist device (LVAD) is unknown. This study sought to determine whether CI is predictive of exercise performance in this patient population and whether it may be overcome by rate-responsive pacing (RRP). Methods and Materials A prospective study of LVAD patients undergoing a cardio-pulmonary exercise test (CPET) was performed. CI was defined as the inability to achieve 80% of the maximal age-adjusted predicted heart rate. Clinical and CPET data were collected and analyzed according to the presence of CI. Results Thirty-six patients were enrolled. Mean age was 58.3 + 13.1 years, 77.8% were men, and 61.1% were bridge-to-transplant. Thirty-one (86.1%) exhibited CI following LVAD placement. The severity of CI was correlated with the peak VO2 (r=0.38, p=0.02). There were no differences between those with and without CI with respect to age, gender, cardiomyopathy type, diabetes mellitus prevalence, disease duration, beta-blocker use, or time on mechanical support. Seven patients had a second CPET with activated RRP 36 + 33 days after the first test. In 4 patients RRP resulted in a higher heart rate and in these patients peak VO2 improved by an average increase of 1.4 + 0.8ml/min/kg. Conclusions CI is common among patients with advanced HF following LVAD placement. The severity of CI correlated with exercise performance in LVAD patients. RRP represents a possible intervention to improve exercise performance. [ figure 1 ]