Prognostic significance of myocardial ischaemia during exercise echocardiography in the absence of angiographic evidence of obstructive coronary disease

Aims We studied the prognostic significance of myocardial ischaemia during exercise stress echocardiography (ExE) in the absence of angiographic evidence of obstructive coronary artery disease (CAD) in a contemporary cohort of patients. Methods and results We retrospectively enrolled 84 patients who underwent ExE and had exercise-induced myocardial ischaemia followed by angiographic coronary evaluation. Fifty-one (61%) patients had non-obstructive CAD (iNOCAD), and 33 (39%) had normal coronaries (iNC). iNC and NOCAD patients were propensity matched to 99 and 153 patients with non-ischaemic ExE, respectively. Compared to iNOCAD, iNC patients were younger (60.9 ± 10.4 vs. 68 ± 8.9 years, P = 0.002) and predominantly women (76% vs. 47%, P = 0.009). Ejection fraction (57 ± 9.4 vs. 56.4 ± 6, P = 0.776) as well as other clinical and demographic variables were similar. During median follow-up of 3.2 years, there were 27 composite adverse cardiovascular events (1 death, 10 acute chest pain events, 2 strokes, and 21 cardiac hospitalizations). iNC was associated with a higher risk of acute chest pain (HR: 19.0, 95% CI: 3.7–93) and the composite adverse outcome (HR: 3.3, 95% CI: 1.7–6.6), compared to matched patients. Similarly, iNOCAD was associated with a higher risk of the composite outcome (HR: 2.2, 95% CI: 1.2–4.2). Conclusion Ischaemic ExE in the absence of angiographically obstructive CAD carries an elevated risk of adverse cardiovascular events necessitating medical optimization and close follow-up for progression.