Significance of ST elevation in lead V1 in acute anterior myocardial infarction: A pulsed wave tissue Doppler echocardiography study

Abstract

Recent studies have focused upon the significance of ST segment elevation (STE) in lead V1 in acute anterior myocardial infarctions (AAMI). Our study investigated whether STE in V1 is associated with alterations in regional and global left ventricular functions determined by tissue Doppler (TD) imaging mitral annulus corners. Standard echocardiography and TD imaging of four sites of mitral annulus were performed to 47 consecutive patients with AAMI within 36 hours of hospital admission. Correlations between the maximum STE amplitude in V1 and TD velocities were analyzed. The amplitude of STE in V1 significantly correlates with early diastolic TD velocities of septal (r= -0.49), anterior (r= -0.47) and inferior mitral annulus (r= -0.51), early to late diastolic TD velocity ratio of inferior mitral annulus (r= -0.48), and mean early diastolic TD velocity (r= -0.52). A subgroup analysis revealed that patients with STE of 2 mm in V1 (32%) had significantly lower peak systolic and late diastolic TD velocity at septal annulus (5.9 ±1.8 cm/s vs. 6.8 ±1.3 cm/s; p=0.03 and 9.1 ±2.5 cm/s vs. 10.6 ±1.8 cm/s; p=0.02, respectively), early diastolic velocity at lateral mitral annulus (6.1 ±1.7 cm/s vs. 8.1 ±2.6 cm/s; p=0.02), and mean systolic TD velocity (6.2 ±1.2 cm/s vs. 6.8 ±0.9 cm/s; p=0.04). In patients with AAMI, a pronounced STE in V1 is associated with high degree of functional impairment involving both infarct-related and apparently best functioning portions of the left ventricle as determined by TD analysis of different mitral annulus corners.