Normal ST Segment Elevation and Electrocardiographic Patterns in the Right-Sided Precordial Leads (V3R and V4R) in Healthy Young Adult Koreans

BACKGROUND AND OBJECTIVES: It is important to analyze right-sided chest electrocardiograms (ECGs) to rule out combined right ventricular infarction in patients with inferior wall infarction. However, the patterns of right-sided chest ECGs in healthy adults have not been thoroughly investigated. This study was conducted to analyze the normal patterns of ECGs and the prevalence of ST segment elevation (STE) in the right-sided precordial leads (V3R and V4R) in healthy adult Koreans. SUBJECTS AND METHODS: One hundred thirty healthy male volunteers who registered at the Armed Forces Daejeon Hospital for military recruitment were enrolled between December 2006 and April 2007. Standard 12-lead ECGs and right-sided precordial ECGs were obtained. The characteristic features of the QRS complex configuration, STE, and T wave morphology from right-sided precordial ECGs were analyzed. RESULTS: The most common QRS configuration in right-sided precordial leads was the rS pattern. The Q waves were present in lead V4R in 4.6% of the study population. STEs of 0.5-1 mm were present in 25.4% of V3R recordings and 6.2% of V4R recordings. T waves were usually negative in the right-sided precordial leads. However, if there was a STE in V4R, the associated T waves were usually positive. There were statistically significant correlations between STEs in V4R and STEs in II, III, aVF, V1, V3, and V6 (p<0.01). CONCLUSION: The STEs, Q waves, and T wave inversions in the V3R and V4R leads were relatively common findings in young, healthy, Korean adults. However, there were no cases in which there was a STE ≥1 mm and a STE concurrently with a q wave.