Positivity rate of stress echocardiography using regional wall motion abnormalities in chronic coronary syndromes

Background Regional wall motion abnormalities (RWMA) remain the cornerstone of stress echocardiography (SE) for diagnosing myocardial ischemia in chronic coronary syndromes (CCS). Historical positivity rates of 60 – 70% have declined over decades. Purpose To evaluate contemporary RWMA-based SE positivity, inter-center and geographic variability, and clinical and procedural factors associated with positivity in CCS. Methods In a prospective multicenter study, CCS patients underwent exercise or pharmacological SE according to local protocols. Stress modalities included treadmill or bicycle, dobutamine, dipyridamole, or adenosine. SE positivity was defined by rest-stress wall motion score index increase (ΔWMSI >0.12), corresponding to worsening of one grade (from 1=normal to 4=dyskinetic) in at least two of 17 segments or two grades in one segment. High-risk studies were defined by ΔWMSI >0.40. Continuous variables are mean ± standard deviation and categorical variables counts and percentages. Comparisons used chi-square test. Patients were grouped into four regions: Americas, Asia/Middle East, Eastern Europe/Russia, Western/Southern Europe. Inter-center variability was explored descriptively. Multivariable logistic regression evaluated factors independently associated with inducible RWMA after adjustment for clinical and procedural variables. Results A total of 11,831 patients (mean age 65±11 years, 39.1% women) from 33 laboratories in 15 countries were included; 1,458 (12.3%) received ultrasound-enhancing agents. Resting WMSI was 1.09±0.24. Overall, 1,355 (11.4%) demonstrated new or worsening RWMA. Among positive studies, 370 (27.3%) were high-risk (ΔWMSI > 0.40), representing 3.1% of cohort. Positivity differed by stress modality: exercise 16.8%, dobutamine 9.0%, vasodilators 3.2% (p<0.001). Inter-center variability ranged from 1.1 to 46.3% (Figure). Geographic differences were observed, with highest positivity rates in Eastern Europe/Russia and lowest in Western/Southern Europe and Asia/Middle East (p<0.001). Using Western/Southern Europe as reference, differences persisted after multivariable adjustment (Table). Factors associated with inducible RWMA were older age (OR 1.03 per year, 95% CI 1.02–1.03), male sex (OR 1.23, 95% CI 1.08–1.42), diabetes (OR 1.17, 95% CI 1.00–1.36), hypertension (OR 1.30, 95% CI 1.09–1.56), dyslipidemia (OR 1.67, 95% CI 1.42–1.97), exercise stress (OR 2.03, 95% CI 1.81–2.28), ultrasound-enhancing agents (OR 2.63, 95% CI 2.13–3.24), high-volume centers (>500 studies entered in data bank) (OR 1.22, 95% CI 1.02–1.48) (all p<0.05). Conclusion SE positivity based solely on RWMA in CCS is currently low and shows inter-center and geographic variability, partly influenced by patient profile and procedural factors. These findings support the need to evolve SE toward a multiparametric and standardized approach to better capture the heterogeneous phenotypes of myocardial ischemia beyond RWMA alone.