Diagnosis of acute right ventricular infarction

Abstract

In acute inferior myocardial infarction (MI) due to right coronary artery occlusion, associated right ventricular infarction (RVMI) is best diagnosed by ST-segment elevation in an additional lead-precordial V4R. 1 Many studies and reviews have confirmed the value of lead V4R in recognizing RVMI and in prompting the clinical recognition of important hemodynamic consequences—systemic venous hypertension, clear lungs, and systemic hypoperfusion with low blood pressure. Appropriate therapy with intravenous fluid and inotropic agents is indicated. A variety of electrocardiogram (ECG) lead and display systems have been proposed as effective in capturing STsegment elevations not apparent in the standard 12-lead format. These include calculated epicardial potentials from 80-site body surface maps using a thoracic volume conductor model; a 24-lead system in which each of the standard 12 leads is inverted, producing an additional 12 leads for analysis, and various methods for predicting ECGs at nonrecorded sites from measured ECGs. An entire recent issue of Journal of Electrocardiology (volume 41 no. 3 May/ June 2008) was devoted to the lead system problem. None of the proposed techniques is widely accepted as yet or available in a standard commercial application. The addition of posterior (V7-V9) and right ventricular (V4R to V6R) leads in all suspected acute MI cases increased the sensitivity of diagnosis by 8.4%. In our method to rapidly identify acute RVMI, only a single additional lead (V4R) is recorded and that only if the word “inferior” has appeared in the computer diagnostic statement. Thus, no time is lost before a necessary V4R is