Objective Non-invasive cardiac imaging may suffer from poor image quality in morbidly obese individuals. This study aimed to determine the clinical value of contemporary stress echocardiography (SE) in morbidly obese patients referred for assessment of suspected coronary artery disease (CAD).

Methods This prospective, multicentre observational study was conducted in two district hospitals and one tertiary centre in London, UK. Individuals with body mass index ≥35 kg/m² referred for SE were evaluated. The percentage of patients with obstructive CAD on coronary angiography, following abnormal SE, was assessed. Patient outcomes were determined with follow-up for the composite end-point of all-cause mortality, myocardial infarction and late revascularisation.

Results Over a 13-month period, 209 morbidly obese patients underwent SE, and contrast agent was used in 96% of patients. A diagnostic result was obtained in 200/209 (96%) patients. Of 32 (15%) patients with inducible ischaemia, 25 underwent angiography, 22 (88%) had corresponding significant CAD and, of these, 16 (77%) underwent revascularisation. Conversely, only 2/157 patients (1.3%) with normal SE underwent angiography, and none underwent revascularisation. Over a mean follow-up period of 17.8±5.4 months, there were nine events. The annualised cardiac event rate after a normal SE was 0.95%. Events were more frequent in patients with inducible ischaemia versus those without ischaemia (5/32 (15.6%) vs 4/153 (2.6%); p=0.002). Ejection fraction <50% (HR 9.5; 95% CI 2.4 to 38.0; p=0.002) and inducible ischaemia (HR 9.4; 95% CI 2.5 to 35.8; p=0.001) were predictors of outcome on univariable Cox regression analysis.

Conclusions Contemporary SE has excellent feasibility and positive predictive value and resulted in appropriate risk stratification of symptomatic patients with significant obesity. A normal SE portends an excellent outcome over the short–intermediate term in this high-risk patient population.