Cardiac catheterization is useful in these patients to further characterize rheumatic MS hemodynamics and etiology of symptoms, as it can measure absolute pressures in the LV, LA, and pulmonary circulation at rest and with exercise. Although the mean pulmonary artery wedge pressure is an acceptable substitute for mean LA pressure, the LV to pulmonary wedge gra- dient will overestimate the true transmitral gradient because of phase delay and delayed transmission of Nonetheless, the absolute mean pulmonary artery wedge pressure and its relationship to the LV diastolic pressure and pulmonary artery pres- sure can provide useful clinical information. The Gorlin equation can be used for an independent calculation of mitral valve area.2,3 CLINICAL STATEMENTS AND GUIDELINES 6.2.1.5. Diagnostic Testing: Exercise Testing Recommendation for Diagnostic Testing: Exercise Testing in Patients With Rheumatic MS COR LOE Recommendation In patients with rheumatic MS and a discrepancy between resting echocardiographic findings and clinical symptoms, exercise testing with Doppler or invasive hemodynamic assessment is recommended to evaluate symptomatic response, exercise capacity, and the response of the mean mitral gradient and pulmonary artery pressure.1 5 Synopsis Exercise testing with either Doppler echocardiography or cardiac catheterization is important when the resting hemodynamics do not match the clinical symptoms in patients with rheumatic MS. Recommendation-Specific Supportive Text 1. Exercise testing with hemodynamics is helpful in the management of rheumatic MS when a patient s symptoms seem significantly greater than or less than would be expected from TTE. Results have been published in which both exercise and dobu- tamine were used with Doppler echocardiography, although exercise is preferred in general as the more Most experience is with tread- mill exercise, with images and Doppler obtained immediately after stress, but bicycle exercise allows data acquisition at various stages of exercise. 