Clinical significance of R-wave amplitude in lead V 1 and inferobasal myocardial infarction in patients with inferior wall myocardial infarction

• Published in: Annals of noninvasive electrocardiology Vol. 29; no. 3; p. e13114
• Main Authors: Zheng, Xiao-Bin, Wu, Hai-Yan, Zhang, Ming, Yao, Bing-Qi
• Format: Journal Article
• Language: English
• Published: United States 01.05.2024
• Subjects: QRS duration; risk stratification; inferior wall myocardial infarction; R‐wave amplitude in V1
• ISSN: 1082-720X; 1542-474X
• DOI: 10.1111/anec.13114

To assess electrocardiogram (ECG) for risk stratification in inferior ST-elevation myocardial infarction (STEMI) patients within 24 h. Three hundred thirty-four patients were divided into four ECG-based groups: Group A: R V <0.3 mV with ST-segment elevation (ST↑) V -V , Group B: R V <0.3 mV without ST↑ V -V , Group C: R V ≥0.3 mV with ST↑ V -V , and Group D: R V ≥0.3 mV without ST↑ V -V . Group A demonstrated the longest QRS duration, followed by Groups B, C, and D. ECG signs for right ventricle (RV) infarction were more common in Groups A and B (p < .01). ST elevation in V , indicative of left ventricle (LV) lateral injury, was more higher in Group C than in Group A, while the ∑ST↑ V R + V R + V R, representing RV infarction, showed the opposite trend (p < .05). The estimated LV infarct size from ECG was similar between Groups A and C, yet Group A had higher creatine kinase MB isoform (CK-MB; p < .05). Cardiac troponin I (cTNI) was higher in Groups A and C than in B and D (p < .05 and p = .16, respectively). NT-proBNP decreased across groups (p = .20), with the highest left ventricular ejection fraction (LVEF) observed in Group D (p < .05). Group A notably demonstrated more cardiac dysfunction within 4 h post-onset. For inferior STEMI patients, concurrent R V <0.3 mV with ST↑ V -V suggests prolonged ventricular activation and notable myocardial damage. RV infarction's dominance over LV lateral injury might explain these observations.