Simple six-item clinical score improves risk prediction capability of stress echocardiography

Objectives To assess the value of a simple score integrating non-ischaemia-related variables in expanding the wall motion abnormalities risk power during stress echocardiography (SE). Methods Study includes 14279 patients who underwent SE for evaluation of coronary artery disease. All-cause death was the end point. Patients were randomly divided into the modelling and validation group of equal size. In the modelling group, multivariate analysis was conducted using clinical, rest and SE data, and a score was obtained from the number of non-ischaemia-related independent prognostic predictors. The score prognostic capability was compared in both groups. Results During a median follow-up of 31 months, 1230 patients died: 622 (9%) in the modelling and 608 (9%) in the validation group (p=0.68). Independent predictors of mortality were ischaemia at SE (HR 1.77, 95%CI 1.49 to 2.12; p<0.0001) and six other parameters: age >= 65 years, wall motion at rest, diabetes, left bundle branch block, anti-ischaemic therapy and male sex. Risk score resulted prognostically effective in the modelling and validation groups, both with and without inducible ischaemia subset. When risk score was included in the multivariate analysis, besides ischaemia at SE it was the only independent predictor of mortality in the modelling (HR 1.70, 95%CI 1.60 to 1.82; p<0.0001), in the validation (HR 1.77, 95%CI 1.65 to 1.90; p<0.0001) and in the overall group (HR 1.73, 95%CI 1.66 to 1.82; p<0.0001). Conclusions Simple clinical variables may be able to optimise SE risk stratification.