The Myocardial Performance Index detects chronic cardiac allograft dysfunction sooner than other methods

AIM: Many noninvasive techniques have been proposed for the early detection of chronic heart graft dysfunction. Diastolic dysfunction may precede systolic dysfunction, and often is prominent; therefore, the aim of the study was to investigate the clinical and prognostic value of a Doppler-derived index of both systolic and diastolic function in heart transplanted patients (Myocardial Performance Index, MPI). METHODS: The MPI was measured in 63 consecutive patients (mean age 55 years, 49 men and 14 women) in sinus rhythm with an orthotopic heart transplantation for at least 1 year (mean 5.3 years) and in 63 age and sex-matched controls. A complete clinical examination was performed at the time of enrollment and was repeated after 3 months. RESULTS: At 3 months, 11 patients (17.5%) presented events (heart failure, hospitalisation or cardiac death). Patients were divided into 2 groups: Group A (52 patients) without events in the follow-up and Group B (11 patients) with events. The values of MPI in Group B (0.55+/-0.19) were significantly higher than values in Group A (0.34+/-0.18, P=0.001). Whereas the values of the index did not differ significantly between Group A and control group (0.34+/-0.18 vs 0.33+/-0.10, P=NS). In the univariate analysis, the population of heart transplanted patients was dichotomised in subgroups by a cut-off MPI of 0.47 and a cut-off ejection fraction (EF) of 50%. Nine patients (41%) with MPI=or>0.47 presented events, while only 2 patients (5%) with MPI<0.47 had any event (P<0.001; c2 12.9). Six patients (85%) with EF<50% had events, while only 5 patients (9%) with EF=or>50% had an event (P<0.001; c2 14). In the multivariate analysis only MPI (chi squared=22.6, P=0.018) and EF (chi squared=20.8, P=0.025) were significant independent predictors of heart failure or cardiac death. By looking at Kaplan-Meyer curves, MPI seems to be better than EF in the earlier detection of graft dysfunction. CONCLUSION: MPI, as a combined systolic and diastolic index, may detect graft dysfunction earlier than EF.