ST-SEGMENT ELEVATION IN RIGHT PRECORDIAL LEADS IMPLIES DEPRESSED RIGHT-VENTRICULAR FUNCTION AFTER ACUTE INFERIOR MYOCARDIAL-INFARCTION

Background The prognosis of acute inferior myocardial infarction is wo rse when it is complicated by right ventricular infarction. ST elevati on in the right precordial leads is one of the reliable methods for de tecting acute right ventricular infarction. The purpose of the study w as to examine the relation between ST elevation in the right precordia l electrocardiographic leads during acute inferior infarction and the severity of right ventricular systolic dysfunction. Methods This study analyzed the relation between ST elevation greater than or equal to 0 .1 mV in V4R and the severity of right ventricular systolic dysfunctio n in 43 consecutive patients (men/women: 35/8; average age 62 +/- 9 ye ars) with acute inferior myocardial infarction with a rapid-response S wan-Ganz catheter to measure the right ventricular ejection fraction ( RVEF). Results RVEF was significantly lower in patients with ST elevat ion (n = 18) than in those without (n = 25) (33% +/- 6% vs 40% +/- 9%, p = 0.010). If the infarct-related lesion was located in the proximal right coronary artery, RVEF tended to be lower than if the lesion was located in the distal right coronary artery or the left circumflex co ronary artery (33% +/- 10% vs 37% +/- 9% vs 42% +/- 9%, p = 0.101). Lo gistic regression analysis demonstrated that ST elevation in V4R was t he only independent predictor of depressed RVEF (odds ratio = 5.31, 95 % confidence interval = 1.28 to 22.1, p = 0.022). Conclusion ST elevat ion in lead V4R during acute inferior myocardial infarction predicts r ight ventricular systolic dysfunction.