Abstract 8126: ST-Segment Elevation in Lead aVR Strongly Predicts Adverse Outcomes at 1 Year in Patients with Non-ST-Segment Elevation Acute Coronary Syndrome

Abstract

Background: In patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), ST-segment depression on admission ECG is recognized to strongly predict poor outcomes; however, lead aVR is not considered. Lead aVR is referred to as a “cavity lead,” and ST-segment elevation in lead aVR (ST↑aVR) may reflect global subendocardial ischemia in NSTE-ACS. Methods: We studied 585 patients with NSTE-ACS who underwent coronary angiography during initial hospitalization. Patients were divided into the 3 groups according to the degree of ST↑aVR on admission ECG: no ST↑aVR (n=422, G-A); ST↑aVR <1.0 mm (n=84, G-B); and ST↑aVR ≥1.0 mm (n=79, G-C). TIMI risk score, summed ST-segment depression in all leads except aVR (ΣST↓), troponin T (TnT), hemoglobin (Hb), high-sensitivity C-reactive protein (hsCRP), estimated glomerular filtration rate (eGFR), and brain natriuretic peptide (BNP) were also measured on admission. Results: There were no differences in sex or coronary risk factors except for diabetes mellitus in the 3 groups. In G-A, G-B, and G-C, age was 66±11, 70±10, and 70±11 years; TIMI risk core was 2.6±1.4, 3.5±1.2, and 4.1±1.2; the rates of diabetes mellitus were 29%, 41%, and 53%; Killip class ≥2 was 5%, 14%, and 28%; positive TnT was 28%, 42%, and 57%; the levels of Hb were 14±2, 13±2, and 13±2 g/dl; hsCRP was 0.329±0.574, 0.540±1.100, and 0.664±1.340 mg/dl; eGFR was 68±25, 62±29, and 58±24 ml/min/1.73 m 2 ; BNP was 157±284, 282±415, and 386±334 pg/ml; ΣST↓ was 1.8±2.4, 6.0±4.0, and 12.3±6.0 mm; the rates of left main or 3-vessel disease were 6%, 42%, and 72%; and major adverse events (death, [re]infarction, urgent revascularization, or congestive heart failure) at 1 year were 11%, 37%, and 46%, respectively (all p<0.01). Multivariate analysis showed that as compared with no ST↑aVR, the hazard ratios (95% CI) for 1-year adverse events associated with ST↑aVR <1.0 mm and ST↑aVR ≥1.0 mm were 2.66 (1.18-5.89; p<0.001) and 4.20 (1.48-10.9; p<0.001), respectively. Conclusions: ST↑aVR on admission ECG is a strong predictor of 1-year adverse outcomes in patients with NSTE-ACS, even after adjusting for traditional risk factors, biomarker profiles, and ST-segment depression in other leads. Our findings suggest the importance of ST↑aVR in early risk stratification.