Chicken or the egg: ST elevation in lead aVR or SYNTAX score.

BACKGROUND: ST-segment elevation in lead aVR (STEaVR) anticipates left main and/or three-vessel disease (LM/3VD) in patients with acute coronary syndromes. STEaVR is generally reciprocal to and accompanied by ST-segment depression (STD) in the precordial leads. SYNTAX score (SS) is an angiographic scoring system and is widely used to evaluate the severity and complexity of coronary artery disease. The purpose of our study was to assess the relationship between STEaVR and SS.

METHODS: We performed a retrospective analysis of 117 patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). Electrocardiograms at presentation were reviewed, especially for ST-segment elevation of ≥ 0.05 mV in lead aVR and STD of ≥ 0.05 mV in more than two contiguous leads. All lesions causing ≥ 50% stenosis in a coronary artery with a diameter of ≥ 1.5 mm were included in the SS calculation. SS was divided into two groups: ≥ 23: high, < 23: low.

RESULTS: Among the 117 patients, 80 (68.4%) had STEaVR and 37 (31.6%) did not. Patients with STEaVR had a higher SS and higher rate of LM/3VD (85 vs 67.6%, p < 0.001; 86.2 vs 72.9%, p = 0.03, respectively) than those without STEaVR. On multivariate analysis, STEaVR [odds ratio (OR) 1.85; 95% confidence interval (CI): 1.20-3.97, p = 0.03] and STD in leads V1 -V4 (OR 2.14; 95% CI: 1.46-4.23, p = 0.002) were independent predictors of a high SS.

CONCLUSION: This study demonstrated that STEaVR was an independent predictor of a high SS.