Recording lead V 4R is associated to enhanced use of fibrinolytic therapy in acute myocardial infarction

Abstract

Background ST-segment elevation in the right-sided chest lead V 4R in inferior wall myocardial infarction is recognized as a sign of proximal occlusion of the right coronary artery with evolving right ventricular myocardial infarction. Our objective is to study how often lead V 4R is recorded in clinical practice and how this might be associated with use of reperfusion therapy and outcome of patients. Methods Recording of lead V 4R in 814 consecutive patients with acute myocardial infarction, administration of therapy, and outcome of the patients during a median follow-up of 285 days (174-313 days) were studied. Results V 4R was recorded in 52% of patients with inferior ST-elevation myocardial infarction. Patients with V 4R recorded were more likely to receive fibrinolytic therapy compared with patients without recording (65% vs 51%; P = .035). In multivariate analysis, recording of lead V 4R (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.2; P = .006), along with age ( P < .001), previous myocardial infarction (OR 2.2, 95% CI 1.3-3.5; P = .002), and diabetes (OR 3.9, 95% CI 1.1-2.4; P = .03) correlated to the use of reperfusion therapy. Patients with lead V 4R recorded had less ( P = .055) reinfarction, unstable angina, stroke, and/or death during follow-up. Conclusions Lead V 4R was recorded in only half of patients with inferior ST-elevation myocardial infarction. Patients with V 4R recorded were more likely to receive thrombolytic therapy than those without recording of the additional chest lead.