To evaluate the effect of lung transplantation on right ventricular (RV) and left ventricular (LV) volumes and function, magnetic resonance imaging (MRI) was performed in 11 patients before and 6 to 24 months after single (n = 7) or double (n = 4) lung transplantation as well as in 15 healthy control subjects. Prior to transplantation, RV end-diastolic (RVEDVI, ml/m2) and end-systolic (RVESVI, ml/m2) volume indices were significantly increased in patients compared with those in control subjects. RV ejection fraction (RVEF, %), although within the lower normal range, was significantly reduced. In contrast, LV volume indices (ml/m2) were significantly smaller in patients than in control subjects, whereas LV ejection fraction (LVEF, %) was not different from that in normal subjects. After lung transplantation, MRI revealed a significant reduction in RVEDVI from 73 +/- 29 to 54 +/- 14 (p = 0.03) and RVESVI from 38 +/- 23 to 20 +/- 6 (p = 0.01) with a concomitant significant increase in RVEF from 48 +/- 14 to 63 +/- 6 (p = 0.01). Consecutively, the LV expanded to normal (LVEDVI from 49 +/- 12 to 65 +/- 14, p = 0.01; LVESVI from 23 +/- 9 to 28 +/- 7, p = 0.05), whereas LVEF remained unchanged (55 +/- 9 versus 56 +/- 8).