Exercise Stress Echocardiography in Degenerative Mitral Regurgitation

he origins of current understanding of hemodynamics and of their echocardiography-based assessment are cardiac catheterization diagnostic techniques. Cardiac catheterization was essential for hemodynamic assessment and diagnosis in the 1950s and 1960s, and it was the gold standard for the validation of Doppler echocardiography developments in the 1980s and 1990s. 1 Furthermore, the assessment of hemodynamics during exertion began with cardiac catheterization 2 only to evolve substantially with echocardiography because of the noninvasive nature of this modality, making it more practical and easy to repeat at follow-up. The study of Utsunomiya et al 3 represents a return back to the origins, revalidating echocardiographic measures of pulmonary pressure and cardiac output during exercise with simultaneous cardiac catheterization and echocardiography in patients with degenerative mitral regurgitation. Echocardiography remains the first-line tool for the assessment of pulmonary artery pressure; however, current guidelines 4 lead to a return back to the origins, recognizing the limitations of echocardiography and, consequently, increasing the role of right heart cardiac catheterization at rest. Nevertheless, during exertion, Utsunomiya et al 3 found good agreement between echocardiographic and invasive measures of pulmonary artery pressure, of cardiac output, of pulmonary vascular resistance, and right ventricular contractile reserve, revalidating the use of supine bicycle stress echocardiography in primary mitral regurgitation. The aim of their study was not to validate exercise echocardiography but to define the mechanisms of exercise intolerance in hemodynamically significant primary mitral regurgitation.