403 ECG EXERCISE STRESS TEST PREDICTORS OF LEFT MAIN CORONARY ARTERY DISEASE


 
 
 Left main coronary artery disease (LMCAD) heavily affects prognosis of patients with suspected CAD. Thus, its identification/exclusion is an important step in the assessment of these patients. Although being the gold standard to identify LMCAD, invasive coronary angiography (ICA) is burdened by some risks, while coronary computed tomography angiography (CCTA) has still limited availability, quite high costs and associated radiologic risks.
 In the past decades, several studies demonstrated the utility of ECG exercise stress test (EST) for the identification of LM disease in patients with suspected CAD. However, the pre-test probability of CAD of subjects undergoing EST has significantly changed in the last decades.
 Accordingly, in this study we aimed to assess the predictive value of EST for the presence/absence of LMCAD in a contemporary population of patients with suspected CAD.
 
 
 
 We retrospectively enrolled 495 consecutive patients, referred to our Center between years 2018 and 2021 because of suspected CAD, who underwent both an EST (standard treadmill Bruce protocol) and ICA (within 12 months of the EST). Patients with a history of coronary artery bypass surgery were excluded.
 
 
 
 Overall, 24 patients (4.8%) were found to have LMCAD at ICA. Among clinical variables, only male gender (p=0.025) and smoking (p=0.003) were associated with LMCAD. A number of ECG leads with EST-induced ST-segment depression (STD) ≥5 and a maximal STD ≥2 mm were more frequently found in patients with, compared to those without LMCAD (29.2 vs 9.8%, p=0.003; and 58.3 vs 24.8%, p<0.001, respectively). No other EST variable was associated with LMCAD, including ST-segment elevation in lead aVR (4.2 vs. 2.6% in the 2 groups, respectively, p=0.63). On the other hand, among the 206 patients (41.6% of the population) who achieved 85% of maximal heart rate predicted for age and had ST-segment depression < 2mm, LMCAD was present in 1.9% only.
 
 
 
 Our data indicate that EST continues to be a valuable tool for predicting the presence/absence of LMCAD in contemporary populations of patients with suspected coronary artery disease.
