ASSESSMENT OF EARLY LEFT-VENTRICULAR REMODELING IN ORTHOTOPIC HEART-TRANSPLANT RECIPIENTS WITH CINE MAGNETIC-RESONANCE-IMAGING - POTENTIAL MECHANISMS

We performed short axis cine magnetic resonance imaging studies in 11 patients 2 months after they underwent orthotopic heart transplantatio n (OHT), and in 10 control subjects, to measure left ventricular (LV) volumes, mass, and end-systolic wall stress to assess ventricular remo deling after OHT. Although there were no significant differences in ve ntricular volumes and ejection fractions between heart transplant reci pients and control subjects, heart transplant recipients had significa ntly higher LV mass (198 +/- 61 vs 132 +/- 27 gm, p = 0.001). As a con sequence of myocardial hypertrophy, end-systolic wall stress was signi ficantly reduced in heart transplant recipients compared with control subjects (34 +/- 16 vs 57 +/- 10 kdyne/cm(2), p = 0.001). Moreover, he art transplant recipients had significantly reduced end-systolic wall stress/volume ratio when compared with control subjects (0.89 +/- 0.3 vs 1.26 +/- 0.3 kdyne/cm(2)/ml, p < 0.01), indicating an already reduc ed LV contractility 2 months after heart transplantation. Univariate r egression analysis revealed a significant correlation between LV mass and averaged cyclosporine levels, but no correlation between LV mass a nd blood pressure, cold ischemic time, acute rejection, age, body mass , blood pressure, plasma catecholamine levels, or plasma renin activit y. Magnetic resonance imaging demonstrates early LV remodeling after O HT with reduced myocardial contractility. Cyclosporine may be contribu ting to these changes.