Left Ventricular Regional Diastolic Dysfunction in Patients with First Myocardial Infarction Determined by Diastolic Motion of the Atrioventricular Plane.

Abstract

Motion of the left ventricular [left ventricle (LV)] atrioventricular (AV) plane has been used to assess systolic LV function. The method has not been used properly to assess diastolic function, especially after a first myocardial infarction (MI). The diastolic function was assessed in 47 previously healthy patients with a first MI assessed by echocardiographic diastolic motion of the LV AV plane. The motion of the AV plane was recorded at four different LV sites, that is, at the septal, anterior, lateral, and inferior walls. Two distinct phases of motion were noticed during diastole at all the sites: one at the early diastole caused by rapid filling of the LV and the other at late diastole during the atrial contraction. The contribution of left atrial contraction to LV filling at different LV sites was calculated by relating the magnitude of the motion caused by atrial contraction to the total diastolic AV plane motion at the respective sites. These left atrial contributions were regarded as the regional diastolic function of the respective LV sites. The global LV diastolic function was determined from the left atrial contribution to total AV plane motion from the above four sites. Patients with anterior MI had a significantly lower ejection fraction than those with inferior MI (41% and 49%, respectively; P < 0.01). Compared with age-matched healthy subjects, the regional atrial contribution to diastolic filling was significantly higher at the anterior wall in anterior MI (38% and 52%, respectively; P < 0.001) and at the inferior wall in inferior MI (43% and 53%, respectively; P < 0.01). The atrial contribution to global LV filling was increased in anterior MI (48% compared with 42% in healthy subjects; P < 0.05) but not in inferior MI. These findings suggest that the diastolic AV plane displacement (AVPD) may be used to assess both the regional and the global diastolic function in patients following an MI.