Long-term changes in left ventricular performance and geometry in the transplanted human heart have been incompletely described. Therefore, two-dimensional echocardiograms were performed on 22 recipients of an orthotopic heart transplant at 1 month (32 +/- 20 days), 1 year (11 +/- 3 months) and 4 years (54 +/- 9 months) after transplantation. All studies were performed at a time when the patient had no pathologic evidence of rejection. Ten healthy men served as a normal control group. Over 4 years of follow-up, mean systolic blood pressure in the study patients increased from 121 +/- 12 (p = NS vs. values in the control group) to 139 +/- 11 mm Hg (p less than 0.05 vs. both control values and values at 1 month); mean diastolic blood pressure increased from 72 +/- 7 (p = NS vs. normal values in the control group) to 93 +/- 8 mm Hg (p less than 0.05 vs. both control values and values at 1 month). Left ventricular end-systolic volume increased from 42 +/- 10 (p = NS vs. control values) to 51 +/- 14 ml (p less than 0.05 vs. both control values and values at 1 month) and end-diastolic volume increased from 103 +/- 28 (p = NS vs. control values) to 112 +/- 27 ml (p less than 0.05 vs. control values) over 4 years. Left ventricular mass and ejection fraction did not change significantly within the patient cohort and remained similar to that found in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)