Dobutamine stress echocardiography (DSE) is being consistently used as an exercise-independent stress modality aimed at the detection of coronary artery disease (CAD) and the evaluation of myocardial ischemia. It may though occasionally induce coronary vasospasm. In this study, we aimed to evaluate the prevalence and predictors of dobuta-mine-related coronary spasm in patients without known CAD and false positive DSE (positive DSE but no significant coronary lesions on angio-gram)

3952 patients referred to our echocardiography laboratory for DSE between January 2010 and May 2012 were prospectively investigated. Those with positive DSE underwent coronary angiograms with systematic methylergometrine intracoronary injection in case of absence of significant coronary stenosis or spontaneous occlusive coronary spasm. Patients with spontaneous occlusive coronary spasm or positive methylergometrine test but no significant stenoses were enrolled and compared with those with positive DSE but no coronary lesions nor spontaneous or induced spasm (« true » false positive DSE)

29 patients with DSE-related vasospasm (19.4% of positive DSE without known CAD) were compared with 56 patients with no lesions and no spam (« true » false positive DSE). They were more frequently smokers (72.4% vs 37.5%; p=0.003); they had more frequently dyslipidemia (79.3% vs 43%;p=0.001); they also had a larger ischemic area at peak DSE (3.4 vs 2.7 segments; p=0.05).

On multivariate analysis, dyslipidemia (HR=10.7; 95% CI= [2.7-42.1]; p=0.001) and active smoking (HR=6.1; 95% CI= [1.7-21.1]; p=0.004) were found to be independant predictors of spam-related DSE rather than « true » false positive DSE.

DSE- related coronary spasm is present in a significant proportion of patients with erroneously labelled « false » positive DSE and should systematically be ruled out. Dyslipidemia and active smoking were independant predictors of spasm rather than « true » false positive DSE