A study of right ventricular infarction in inferior wall myocardial infarction

Background: Right ventricular infarction (RVI) is frequently associated with inferior wall myocardial infarction (MI). Methods: This study was designed to identify the burden of RVI in patients presenting with inferior wall MI (n=50) by right precordial electrocardiogram (ECG) and comparing it with echocardiography (ECHO). Results: Their mean age was (54.5 ± 11.9 years); there were 42 males. ST elevation of greater than 1 mm in right precordial leads (RPL) suggestive of RVI was evident in 16 (32%) cases. Among the RPL (V3R - V6R) V4R and V5R showed sensitivity of 87.5%. The 12-lead ECG finding of ST-elevation greater than 1 mm in lead III and lead III/II greater than 1, had poor sensitivity (75%), specificity (88.2%) compared to ST- elevation of greater than 1 mm in any of the RPL (100%). Both the echocardiography criteria, namely right ventricular end-diastolic dimension (RVEDD) greater than 25 mm (92.3%) and the ratio of RVEDD to left ventricular end-diastolic dimension (RVEDD/LVEDD) greater than 0.7 (90%) indicating right ventricle (RV) dilatation was observed significantly more frequently in RVI group. Conclusions: RVI occurs in more than one-third of patients with acute inferior wall MI. All the patients with inferior wall MI should have RPL recorded as early as possible for evidence of RVI, of which V4R, V5R have the highest sensitivity.