Clinical significance of ST-segment elevation in lead V1 in patients with acute inferior wall Q-wave myocardial infarction.
BACKGROUND
This study was designed to determine the clinical significance of ST-segment elevation in the precordial leads (leads V1 and V2) in acute Q-wave inferior wall myocardial infarction.


RESULTS
One hundred fifty-eight consecutive patients with acute Q-wave inferior wall myocardial infarction were classified into 3 groups on the basis of the initial ST-change in V1 (group 1 = 29 patients with ST elevation, group 2 = 97 patients with ST depression, and group 3 = 32 patients with no ST-segment change). The right coronary artery was the infarct-related artery in all the patients in group 1. Although there was no significant difference between groups 1 and 2, the number of left ventricular asynergic segments was larger and the incidence of major in-hospital arrhythmias was higher in groups 1 and 2 compared with group 3. Patients in group 1 had a significantly higher incidence of proximal lesion (86%) and right ventricular infarction (69%) than the other 2 groups did. When ST elevation in leads V1 and V2 was considered, 14 of 15 patients (93%) with ST elevation only in V1 had right ventricular infarction, whereas 6 of 14 patients (43%) with ST elevation in both V1 and V2 had right ventricular infarction (P =.011).


CONCLUSIONS
ST-segment elevation in V1 on admission in patients with acute Q-wave inferior wall myocardial infarction indicates a right coronary artery lesion associated with a larger infarct size and a higher incidence of major in-hospital arrhythmias.
Tsuka
Y
Y
Second Department of Internal Medicine, Kansai Medical University, Osaka, Japan.
Sugiura
T
T
Hatada
K
K
Nakamura
S
S
Yuasa
F
F
Iwasaka
T
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000150:complications; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology*