Dobutamine stress echocardiography for noninvasive assessment and risk stratification of patients with rheumatic mitral stenosis

OBJECTIVES: We sought to evaluate the impact of dobutamine stress echocardiography (DSE) in patients with known rheumatic mitral stenosis (MS) in order to assess its safety, feasibility, and prognostic correlation to well-known clinical outcomes. BACKGROUND: Noninvasive prognostic assessment of MS still represents an unresolved task in patients with clinically challenging disease. METHODS: Dobutamine stress echocardiography was performed in 53 patients with MS (8 males; age 37.4 +/- 11.3 years) with no major complications. RESULTS: During follow-up (60.5 +/- 11.0 months), 29 patients presented with clinical events: 16 hospitalizations, seven cases of acute pulmonary edema, and six symptomatic supraventricular arrhythmias. On multivariate analysis, the diastolic mitral valve mean gradient at peak DSE (DSE-MG) was the best predictor of clinical events (p < 0.008), especially in patients with moderate disease (p < 0.001). The best performance of DSE for the detection of clinical events was obtained at a cut-off value of 18 mm Hg DSE-MG (sensitivity 90%, specificity 87%, and accuracy 90%). The addition of DSE to the conventional cardiology work-up would allow a 17% increment for the detection of high-risk patients in the entire population and a 40% increment in patients with presumed moderate disease. CONCLUSIONS: In patients with MS, DSE is a safe and highly feasible stress test. A DSE-MG > or =18 mm Hg identifies a subgroup of high-risk patients in whom a more aggressive approach may be warranted; on the other hand, patients with a DSE-MG <18 mm Hg predicts an uneventful clinical course and may justify a more conservative strategy.