Electrocardiogram criteria of limb leads predicting right coronary artery as culprit artery in inferior wall myocardial infarction: A meta-analysis

BACKGROUND

Prior studies have proposed several electrocardiogram (ECG) criteria in limb leads for identifying the culprit coronary artery (CCA) in patients with acute inferior wall myocardial infarction (IWMI). The aim of our study was to conduct an evidence-based evaluation and test accuracy comparison of these criteria.

METHODS

We searched the PubMed, Embase, and Ovid. Eligible studies to assess the diagnostic performance of ECG criteria predicting CCA in IWMI were reviewed for inclusion. A diagnostic meta-analysis of bivariate approach was performed for pooled estimates of sensitivity and specificity, and meta-regression was implemented to investigate sources of heterogeneity.

RESULTS

Twenty-four studies with 4431 unique participants met the inclusion criteria. The pooled sensitivity and specificity for ST-segment elevation (STE) in III > II, ST-segment depression (STD) in I, STD in aVL, STD in aVL > I, STE in III > II, and STD in aVL > I were 0.91 (0.88-0.94) and 0.69 (0.53-0.81), 0.80 (0.73-0.87) and 0.69 (0.62-0.76), 0.90 (0.81-0.95) and 0.41 (0.22-0.62), 0.84 (0.75-0.91) and 0.72 (0.48-0.88), and 0.79 (0.62-0.90) and 1.00 (0.37-1.00), respectively. Heterogeneity investigation showed that whether multi-vessel diseased patients were excluded, sample size, publication year, etc., could influence the diagnostic performance.

CONCLUSION

STE in III > II performed better than other criteria for predicting RCA as CCA in IWMI, and STE in III > II and STD in aVL > I were potential and simple algorithms. ECG could be an effective tool to identify the CCA, but future studies are clearly needed to address the potential of diagnostic and prognostic value.

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.