SUMMARY
Objective. To evaluate the role of functional and imaging parameters during exercise stress echocardiography (SE) in the presence of ST-segment elevation (ST-E) in aVR leads to predict significant left main/left main equivalent/or ostial left anterior descending (LAD) stenosis (LM+). Methods. The study population included 548 patients with ECG and echo markers of myocardial ischemia, in whom diagnostic coronary angiography was performed. We analyzed the patients’ clinical characteristics, ECG changes, wall motion score index (WMSI) by stress echocardiography (SE), as well as functional capacity during exercise (METs) and Duke treadmill score.Results. aVR ST-segment elevation was found in 60/548 (11%) patients, whereas aVR ST-E was found in 23/57 patients with left main LM stenosis (Sn 40%, Sp 92%, PPV 38%, NPV 93%). When aVR ST-E was combined with other functional/imaging parameters, patients with aVR ST-E and LM+ had significantly worse functional capacity in METs (5.0±2.2 vs. 6.7±2.3, P=0.005), lower Duke score (-6.8±6.8 vs. -3.6±4.1, P=0.049), and higher deterioration of WMSI (0.51±0.24 vs. 0.39±0.24, P=0.046). Significant multivariable predictors of the left main (LM) stenosis were aVR ST-E and positive SE in LAD territory in the whole group of patients, and Delta WMSI, Duke score and METs achieved in patients presented with aVR ST-E during exercise.Conclusion. The aVR ST-segment alone has intermediate sensitivity in detecting significant LM stenosis in patients referred to SE testing for chest pain. When combined with other functional and imaging parameters, including poor exercise functional capacity in METs, lower Duke score or greater WMA in the territory of LAD, its diagnostic power to detect LM significantly increases.