Objective: In adults after successful heart transplant, the cardiorespiratory function is still suboptimal. Such data in pediatric recipients are still scarce.
Methods: From April 2007 to November 2008, six children (five male and one female), four with dilated cardiomyopathy and two with complex heart disease, underwent orthotropic heart transplantation (OHT) at the age of 14±3.1 years. Grade exercise testing with breath-by-breath gas analysis was performed using an incremental cycling at 31.5±7.3 days after surgery.
Results: Pediatric recipients had significant impairment in workload (58±31 watts), oxygen consumption (18.4±3.5 mL/Kg/min), and oxygen pulse (7.6±2.4 mL/beat) at peak exercise one month after OHT. Typical heart rate responses of a denervated heart with the manifestation of higher resting heart rate (96±10 beats/min), lower peak heart rate (119±22 beats/min) during exercise, and continuous heart rate increase toward 1 to 2 minutes after cessation of exercise were also demonstrated.
Conclusions: Pediatric OHT recipients have a low cardiopulmonary endurance during the early postoperative period. Such early cardiorespiratory response to exercise was also observed in adult recipients. Therefore, an early multidisciplinary cardiac rehabilitation program given in adults should also be incorporated into the postoperative follow-up of pediatric recipients to enhance the physical capacity and improve the quality of life.