Objective: Heart transplantation improves the survival rate and quality of life in patients with severe symptoms of congestive heart failure and an ejection fraction of 20% or less. Despite marked symptomatic and clinical improvement in those who undergo heart transplantation, exercise capacity often remains reduced, and the factors limiting exercise performance during the post-transplantation period remain unclear. This study was performed to investigate the factors affecting exercise capacity in heart transplantation recipients.
Patients and methods: Fourteen patients with cardiomyopathy were enrolled in this study. We measured peak exercise oxygen uptake (peak VO(2)) in seven patients (age range: 42 +/- 14 yr) 10-28 months after transplantation, in seven patients (age range: 33 +/- 18 yr) with dilated cardiomyopathy before heart transplantation, and in 14 healthy control subjects (age range: 44 +/- 12 yr). The left ventricular ejection fraction, Beck Depression Inventory score, Medical Outcome Health Survey Short Form-36 Questionnaire (SF-36) results, and immunosuppressive therapy administered were recorded in all patient groups.
Results: All patients in the post-transplantation group terminated exercise testing before the anaerobic threshold because of general fatigue. All heart transplantation recipients exhibited a left ventricular ejection fraction within the normal range (mean +/- SD = 57% +/- 2%). The peak VO(2) mean values were significantly different among the three groups (p = 0.001). There were statistically significant correlations between the peak VO(2) values and the Beck Depression Inventory scores (r = -0.637, p = 0.01), between the peak VO(2) values and bodily pain (r = 0.717, p = 0.006), between the peak VO(2) values and general health perceptions (r = 0.706, p = 0.007), and between peak VO(2) values and postoperative duration (r = 0.843, p = 0.03) in all patient groups.
Conclusion: In the long-term treatment of heart transplant recipients, exercise training should be considered an important therapeutic tool that enables patients to achieve a good quality of life.