Myocardial performance index evaluated with tissue doppler echocardiography at early, intermediate and late phase of acute myocardial infarction

ABSTRACT

In this study, ejection fraction% [EF%] and myocardial performance index [MPI] were recorded in 67 survivors at early, intermediate and late phase of acute myocardial infarction [AMI] .EF% was echocardiographically obtained by the Simpson's method; MPI was calculated using Tissue Doppler Echocardiography [IDE] derived from isovolumetric contraction time [ICT]; isovolumetric relaxation time [IRT] and ejection time [ET]. Results were compared with those obtained in 70 controls matched for age and sex.At hospital discharge [early evaluation], EF% was < 50% with significant increase in MPI in respect to the healthy controls [increase in ICT, significant reduction in ET and IRT was unchanged]. Six months later [intermediate evaluation], EF% still resulted in < 50%, MPI was slightly reduced with further increase in ICT and IRT in comparison to the early evaluation, and slight reduction in ET Finally, one year later [late evaluation], in spite of increase in EF>50%, MPI was still increased, with slight rise in ICT, almost normalization in ET, but more evident increase in IRT. The outcomes of MPI demonstrate that in post-AMI patients, late prevalent diastolic ventricular dysfunction occurs following an early systolic dysfunction. In this study, EF% appears to be less sensitive than MPI in defining late post-AMI left ventricular dysfunction. Finally,TDE seems to be more sensitive than conventional Doppler method in measuring MPI