Cardiopulmonary exercise testing in the evaluation of functional capacity after treatment of lymphomas in adults

The present study assessed several parameters of cardiopulmonary function in patients, after treatment for aggressive non-Hodgkin's lymphoma and Hodgkin's disease, to determine the influence of these parameters on patient's performance status. One hundred and six patients (66 male and 40 female) aged 40 +/- 15 years were examined 1-2 years (median 14 months) after anticancer treatment. The patients were examined by means of rest and dynamic stress echocardiography and cardiopulmonary exercise. The rest and post-exercise ejection fraction (EF), Doppler parameters of left ventricular diastolic function and peak oxygen consumption (pVO2) were used as parameters of cardiopulmonary performance. The cumulative dose (CD) of doxorubicin (DOX) given was 240 +/- 70 (240 mg/m2). Thirty-seven percent of patients received mediastinal irradiation in accordance with the used treatment protocol. Sixty-four patients (60%) experienced fatigue after the treatment. Three patients (3%) demonstrated an decreased EF <50%, 34 (32%) demonstrated impaired diastolic function, 14 (13%) demonstrated decreased pVO2<20 ml/kg/min and 15 (14%) demonstrated a value of pVO2 below the reference value, respectively. None of the patients exhibited clinical signs of heart failure. Apart from three patients with a rest EF<50%, all the other patients responded to stress echocardiography with an increment of EF > 5%. The parameter pVO2 significantly correlated with stress EF (0.58, P < 0.0002). A significant relationship was found with all parameters of diastolic function: to index E/A of diastolic filling (r = 0.67, P < 0.0001), isovolumic relaxation time (r = -0.56, P < 0.0009) and to deceleration time (r = -0.54, P < 0.009), respectively. A negative relationship was found with age (r = -0.74, P < 0.0001), CD of DOX (r = -0.53, P < 0.003) and radiotherapy-involving mediastinum (r = - 0.44, P < 0.04), respectively. Using multivariate analysis, a significant relationship was found between pVO2 and parameters of diastolic filling, age, female sex and CD of DOX, respectively (r = 0.58, P < 0.0001). Diastolic dysfunction was correlated with age, CD of DOX and radiotherapy-involving mediastinum, respectively (r = 0.51, P < 0.01). The results show that diastolic dysfunction was the most affected parameter of cardiopulmonary function in cancer survivors. This parameter negatively influenced cardiopulmonary performance and was significantly correlated with the cumulative dose of doxorubicin given and radiotherapy on mediastinum. Despite a high number of patients experiencing fatigue, the study demonstrates that only a relatively small number of patients show a depressed pVO2 on a cardiopulmonary stress test and other cardiac abnormalities. The results of the tests support the introduction of regular aerobic exercise for cancer survivors to increase their cardiopulmonary performance and well-being. Hypothetically, aerobic training may also positively influence diastolic function. However, this assumption warrants a prospective follow-up.