Therapy and Prevention Cardiac Transplantation

We have tested the feasibility and effectiveness of a 2 year (average 16 7 months) walk/jog exercise program on 36 male orthotopic cardiac transplant patients (21 to 57 years old) seen initially 2 to 23 months after surgery. Comparison of initial exercise test results with those in 45 age-matched normal men showed the patients to have a lesser lean body mass (56 ± 7 vs 63 ± 8 kg, p < .001), with a higher resting heart rate (104 ± 12 vs 77 14 beats/min, p < .001) and systolic (138 ± 16 vs 129 ± 17 mm Hg, p < .001) and diastolic (95 14 vs 84 ± 10 mm Hg, p < .001) blood pressures. Peak power output was less than normal (101 27 vs 219 ± 41 W, p < .001), as was peak heart rate (136 ± 15 vs 176 ± 13 beats/min, p < .001), peak oxygen intake (V02max) (22 + 5 vs 34 ± 6 ml.kg.min -', p < .001), and absolute anaerobic threshold (1.18 ± 0.40 vs 2.04 + 0.40 liters-min1, p < .001). Peak ventilatory equivalent was higher (48 ± 9 vs 37 ± 6 1.11, p < .001). Cardiac output (Q), as estimated by the CO2 rebreathing method, was slightly above normal at rest (p < .0 1), but below normal at two submaximal work rates. The group's average weekly training distance was 24 km, with eight highly compliant patients progressing to 32 km or more weekly. After training, lean tissue increased ( + 2.4 + 3.1 kg, p < .001), and resting values were reduced for heart rate (-4 ± 11 beats/min, p < .05), systolic (-13 ± 20 mm Hg, p < .001), and diastolic (9 17 mm Hg, p < .001) blood pressures. There were significant reductions in submaximal values for minute ventilation (VE), ratings of perceived exertion, and diastolic blood pressure at equivalent workloads. Peak values increased for power output ( + 49 + 34 W, p < .001), VO2max ( + 4.0 ± 6.0 ml-kg.min1, p < .001), VE ( + 20 ± 20 1 *min', p < .001), and heart rate ( + 13 + 17 beats/min, p < .001), and decreased for diastolic blood pressure (-8 ± 15 mm Hg, p < .001). In the eight highly compliant patients a greater decrease occurred in resting heart rate (1 1 ± 5 beats/min, p < .001) and submaximal heart rate (range 5 to 10 beats/min less at each power output), with a greater increase in peak power output (+ 68 + 42 W, p < .001), and V02max (+ 11 ± 6 mlkgmin p < .001). The slope of the Q/V02 line was unchanged by training. There was no evidence of cardiac reinnervation in any patient. We conclude that exercise rehabilitation is justified because of its ability to increase working capacity and thus quality of life in cardiac transplant patients. Circulation 77, No. 1, 162-171, 1988. CARDIAC TRANSPLANTATION is now an accepted treatment for end-stage cardiac disease, with actuarial survival rates of 78% for the first 2 years' and greater than 60% for the first 5 years after operation.2 3 Nevertheless, to date there have not been any reports on the effect of a long-term endurance-type exercise training program on the cardiorespiratory function of a large group of such patients. From the Toronto Rehabilitation Centre, Toronto, Ontario, Canada, and Harefield Hospital, Middlesex, England. Address for correspondence: Terence Kavanagh, M.D., Medical Director and Associate Professor of Rehabilitation Medicine, Toronto Rehabilitation Centre, 345 Rumsey Rd., Toronto, Ontario, CanadaM4G 1R7. Received June 11, 1987; revision accepted Sept. 24. 1987. 162 Consequently, the functional status of 36 male orthotopic cardiac transplant recipients was assessed at entry to and at the end of a 16 month training program. The initial status of the patients was compared with the findings in 45 age-matched male volunteers.