CARDIOVASCULAR MEDICINE Myocardial performance index for assessment of left ventricular outcome in successfully recanalised anterior myocardial infarction

Objective: To investigate whether the myocardial performance index (MPI) can predict left ventricular functional outcome in patients with early recanalisation after anterior acute myocardial infarction (MI) and to determine when the index should be measured. Design: MPI was measured serially by two dimensional Doppler echocardiography after successful percutaneous coronary intervention (PCI). Left ventricular function was evaluated by echocardiography and left ventriculography. To assess coronary microvascular damage, the coronary flow velocity pattern was measured immediately after PCI with a Doppler guidewire. Setting: Hiroshima City Asa Hospital. Patients: 32 consecutive patients with their first anterior acute MI who had complete occlusion of left anterior descending coronary artery. Interventions: Successful PCI within six hours of symptom onset. Main outcome measures: Left ventricular anterior wall motion score index (A-WMSI), left ventricular end diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and left ventricular end diastolic volume (LVEDV). Results: There was a significant negative correlation between MPI on day 2 and the coronary diastolic deceleration time (r = 20.66, p , 0.002), as well as a significant positive correlation with the coronary diastolic deceleration rate (r = 0.74, p , 0.0001). MPI on day 2 was significantly correlated with the short and long term changes of A-WMSI and with the short term changes of LVEDP. Furthermore, MPI on day 2 was significantly correlated with the short and long term changes of LVEF (r = 20.52, p , 0.003, and r = 20.64, p , 0.0008, respectively) and of LVEDV (r = 0.51, p , 0.003, and r = 0.41, p , 0.05, respectively). Conclusions: Doppler derived MPI on day 2, representative of the early coronary microvascular state, can predict the left ventricular functional outcome after early successful recanalisation of a patient’s first anterior acute MI.