Early hemodynamic changes versus peak values: what is more useful to predict occurrence of dyspnea during stress echocardiography in patients with asymptomatic mitral stenosis?

Background: In asymptomatic mitral stenosis (MS), the usefulness of peak exercise Doppler echocardiography (DE) values is acknowledged, but the role of values recorded during the first stage of DE remains unclear.

Methods: DE was analyzed in 48 asymptomatic patients with significant MS and revealed dyspnea in 22 patients (46%).

Results: MS severity and rest and peak systolic pulmonary artery pressures (SPAPs) were not different between patients who did and did not develop dyspnea. Progressions of mean gradient and relative SPAP (ratio of SPAP/baseline SPAP) were significantly greater in patients who developed dyspnea compared with those who did not (P < .01), whereas no difference was observed for absolute SPAP progression (P = .28). Onset of dyspnea was associated with a high increase of relative SPAP (>90% at 60W, OR 2.31; CI, 1.2-4.8; P = .02) but not with the 60 mm Hg peak SPAP threshold (OR 1.3; CI, 0.7-43.1; P = .40).

Conclusion: DE reveals symptoms in 46% of patients who are considered asymptomatic. Despite similar peak values, these patients have different hemodynamic parameters during the first level of exercise compared with patients remaining asymptomatic. This may lead to the integration of early hemodynamic changes in the evaluation of exercise tolerance.