RESUMO
Preoperative peak oxygen uptake ( V . O2peak ) and ventilatory efficiency ( V . E / V . CO2slope) are related to the vital prognosis after cardiac transplantation (HTx). The objective of our study was to evaluate the effects of exercise-based cardiac rehabilitation (ECR) program on the preoperative exercise capacity of a HTx candidate. A male patient, aged 50-55 years, with chronic heart failure was placed on the HTx list and performed 12 weeks of intensive ECR (5 sessions-a-week). Our results showed that the cardiac index continuously increased between the onset and the end of ECR (1.40 vs. 2.53 L.min-1.m2). The first 20 sessions of ECR induced a V . O2peak increase (15.0 vs. 19.3 ml.min-1.kg-1, corresponding to 42.0 and 53.0% of its maximal predicted values, respectively). The peak V . O2 plateaued between the 20th and the 40th ECR session (19.3 vs. 19.4 ml.min-1.kg-1) then progressively increased until the 60th ECR session to reach 25.7 ml.min-1.kg-1, i.e., 71.0% of the maximal predicted values. The slope of V . E/ V . CO2 showed a biphasic response during the ECR program, with an increase between the onset and the 20th ECR session (58.02 vs. 70.48) and a decrease between the 20th and the 40th ECR session (70.48 vs. 40.94) to reach its minimal value at the 60th ECR session (31.97). After the first 40 sessions of the ECR program, the Seattle Heart Failure Model score predicted median survival time was estimated at 7.2 years. In conclusion, the improvement in exercise capacity and cardiorespiratory function following the ECR helped delay the heart transplant surgery in our patient awaiting heart transplantation.
