Functional correlates of ischemic electrocardiographic changes during stress echocardiography. data form stress echo 2030 survey

Abstract Background/Introduction Cardiac stress tests are carried out in populations with a low probability of ischemic heart disease (IHD) much more frequently than in the past. Stress ECG remains a frequently used modality for the diagnosis of IHD in vast areas of the world with limited facilities. Purpose To assess the diagnostic value of stress ECG for diagnosing IHD using inducible regional wall motion abnormalities (RWMA) on stress echocardiography (SE) as the gold standard method of diagnosis. Methods The 12-lead ECG response was retrospectively analyzed in 4317 patients (age 64±13 years, 59.6% males) undergoing SE for chronic coronary syndromes who were prospectively recruited from 39 cardiac centers between March 2021 and February 2024. Exclusion criteria were left bundle branch block or pacemaker rhythm. ECG response was considered ischemic according to standard criteria (if ST-segment deviated >1.0 mm from baseline in ≥2 contiguous leads at 80 ms from J point) during an exercise (n=2980, 69.8%), dobutamine (n = 766, 18.0%), or vasodilator (n=519, 12.2%) SE. All patients underwent a comprehensive SE protocol with an assessment of wall motion score index (WMSI), B-lines (4-site simplified score), left ventricular contractile reserve (LVCR) based on force, coronary flow velocity reserve (CFVR) in the mid-distal left anterior descending artery (LAD), and heart rate reserve (HRR). Results ECG changes occurred in 641 patients (14.8%, Group 1) for the overall studied population. Compared to patients without ECG changes (Group 2, n=3676, 85.2%), patients with ECG changes showed higher values of peak WMSI and lower values of CFVR and LVCR (see table).Amongst patients without inducible RWMA (n=3553), there were 392 (11%) patients with an ischemic ECG at stress (89% specificity). Of 764 patients with inducible RWMA during SE, 249 had an ischemic ECG trace (sensitivity 33%). In patients without inducible RWMA, those with ischemic ECG changes showed similar abnormal stress B-lines (23% vs. 21%, p=0.719), LVCR (61% vs. 63%, p=0.602), CFVR (31% vs 33%, p=0.607) and HRR (37% vs 41%, p=0.097) compared to those without ECG changes. Amongst patients with inducible RWMA and ECG changes, CFVR was significantly lower in patients with ECG changes (39.2% and 60.8%, respectively, p<0.001). Conclusions Simple standard stress ECG diagnostic value in the current era in populations with a low probability of IHD seems to be low. However, during SE, stress-induced ischemic ECG changes are associated with more extensive RWMA and blunted global LVCR, with reduced CFVR in the LAD. Therefore, analysis of ST segment changes during stress imaging studies can offer additional, significant information.