The authors evaluated using clinical and echocardiographic examination the effect of chemotherapy involving bolus administration of doxorubicin on the heart muscle in 90 patients with non-Hodgkin lymphoma and with Hodgkin lymphoma. In 18% of patients they found an asymptomatic decrease of the left ventricular ejection fraction during chemotherapy, chronic cardiotoxicity was recorded in 5% patients, in 2% of the patients one year after termination of chemotherapy a clinically latent myocardial infarction was found. The diastolic function was impaired (impaired relaxation) in 44% patients after terminated chemotherapy and in 50% after one year. Echocardiographic examination provided evidence that the impaired systolic and diastolic function persists even after one year following termination of chemotherapy. High-dose chemotherapy with administration of peripheral stem cells did not lead to marked deterioration of left ventricular function as compared with patients who did not undergo this treatment. The main clinical complications--death, cardiotoxicity, relapse of the malignant disease, cardiovascular complications--were present in the course of a 18.5-month follow up after establishment of the diagnosis in 32% of the patients.