Changes in left and right ventricular function of donor hearts during the first year after heart transplantation

Objective Expected values of tissue Doppler imaging (TDI) velocities and myocardial performance index (MPI) after heart transplantation (HTx) have not been evaluated. This study assessed left and right ventricular (LV and RV) structure and function during the first year after HTx using these indexes. Methods and results Echocardiography including MPI and TDI systolic (S'), early (E') and late (A') diastolic velocities of RV and LV were performed in 20 donors (mean age 35 +/- 13 years) and serially in 20 recipients (mean age 59 +/- 9 years) during the first year after HTx. Increase in LV mass occurred at 7 days, with normalisation at 3 months (p<0.001). An increase in MPI (p<0.001) and a decrease in E', S' velocities on TDI occurred at week 1 with gradual improvement during the first year (p<0.001). Normalisation of LV and RV MPI occurred at 6 months (p<0.001) and LV TDI velocities at 1 year (p<0.001). TDI velocities of both ventricles, however, at 1 year remained lower than at baseline. No patient had greater than grade IA rejection during the follow-up. No significant change was found in myocyte size within the first year. However, there was a 3.3-fold increase in fibrosis. Conclusions This study is the first to identify the normal changes of TDI and MPI of both ventricles during the first year after HTx. An increase in LV mass and impairment of bi-ventricular systolic and diastolic function occur early after HTx with gradual improvement during the first year. No significant changes in myocyte size were observed, but there was a substantial increase in fibrosis.