We studied the global and regional left ventricular function, its determinants and its modification with time, in orthotopic heart transplant recipients. We reviewed the left ventricular cineangiography performed 1 (50 patients), 2 (33 patients), 3 (18 patients), and 4 (seven patients) years after operation. Regional wall motion was quantitatively evaluated by the area method. All patients had angiographically normal coronary arteries and no evidence of acute rejection at the time of the study. One year after heart transplantation, cardiac index and left ventricular ejection fraction were mildly but significantly lower than normal. Cardiac index was more than 2.5 L/min/m2 in all but one patient, and ejection fraction was more than 50% in all patients. Only previous acute cardiac rejection necessitating therapy and arterial hypertension showed some influence on the left ventricular function. Two years after operation, the left ventricular end-diastolic volume was increased, and left ventricular mass-volume ratio decreased compared with year 1. Three years after operation, an increase of left ventricular end-diastolic pressure and of left ventricular ejection fraction was also evident. Four years after operation, the heart rate was higher, compared with previous years. Even if the changes in the parameters of left ventricular function were significant, they were small in terms of absolute value. Regional hypokinesia was detected 1 year after heart transplantation in eight patients, involving one segment in six patients and two segments in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)