VALUE OF ST-SEGMENT ELEVATION IN LEAD aVR IN NON STELEVATION MYOCARDIAL INFARCTION/UNSTABLE ANGINA IN PREDICTING DISEASE EXTENT, SEVERITY AND OUTCOMES.

Abstract

Background: ST -segment elevation (STE) in lead aVR has been associated with three vessel disease and left main coronary stenosis in acute coronary syndrome, but prognostic relevance of this finding as an independent predictor in patients with non ST elevation myocardial infarction(NSTEMI) or unstable angina (UA) remains unknown. Methodology: We prospectively evaluated the initial electrocardiogram (ECG) in 112 patients with NSTEMI or UA. ST-elevation in lead aVR was measured. Echocardiography was performed, mitral regurgitation and left ventricular ejection fraction (LVEF) were assessed. Selective coronary angiography was performed at median of 3 days after admission, SYNTAX and Gensini scores were calculated. All the patients were followed up in hospital and 3 months after discharge. Results: Overall, 34 patients (30.3%) had STE in lead aVR (group A) and remaining 78 patients (68.7%) had NSTE (Group B). Group A patients had a higher prevalence of lateral leads ST–segment depression (p=0.001). However, group A peak troponin I (p =0.14) and LVEF ( p= 0.22) were not significantly different, but had a higher incidence of mitral regurgitation (MR) (p=0.02). The incidence of single vessel disease, double vessel disease and triple vessel disease in group A were 41%, 29.3% and 23.5%, whereas in group B they were 49%, 33.3% and 10% respectively (p=0.43, p=0.67 and p=0.06 respectively). The mean SYNTAX score was 24.56±16.43 in group A and 19.46±14.39 in group B (p = 0.47). The mean Gensini score was 64.73±40.70 in group A as compared to 46.32±39.43 in group B (p =0.53). There was no significant difference in 3 months clinical outcomes in the two groups. Conclusion: Our study showed that in NSTEMI/Unstable angina, ST elevation in aVR is associated with ST depression in lateral leads and significant MR. Readmission due to acute coronary syndromes was significantly higher in patients with STE in aVR. However, there was no significant difference in troponin I levels, LVEF, disease extent by Gensini and SYNTAX score between the two groups.