Diagnostic Testing: Cardiac Catheterization Left ventriculography and hemodynamic measurements are useful when clinical assessment and noninvasive tests are inconclusive or discordant with regard to 1) se- verity of MR, 2) LV function, or 3) the need for surgery.1 Noninvasive imaging is adequate for evaluation of MR in most cases. However, invasive hemodynamic evalu- ation may be necessary in some cases, especially when there is a clinical discrepancy between symptomatic sta- tus and noninvasive testing. Elevated filling pressures support a cardiac cause of dyspnea and may indicate severely abnormal pathophysiology even when the pa- tient claims to be asymptomatic. Conversely, a normal invasive hemodynamic examination in a symptomatic CLINICAL STATEMENTS AND GUIDELINES patient with what appears to be less than severe MR suggests a noncardiac cause for the symptoms. Hemo- dynamic evaluation can be especially helpful in patients with concomitant lung disease. Normal LA (or pulmo- nary artery wedge) pressure and a large transpulmonary gradient suggest pulmonary hypertension that is attrib- utable to lung disease rather than mitral valve disease. Left ventriculography may also be of diagnostic benefit. Whereas echocardiographic-Doppler interrogation of the mitral valve measures flow velocity, ventriculography uses the density of contrast to determine the amount of blood flow from the LV to the LA. Although only semi- quantitative, a carefully performed ventriculogram can help in quantifying MR severity. Additional hemodynam- ic interventions, such as exercise or leg raising, may be helpful when the resting information is equivocal. 7.2.2.5. Diagnostic Testing: Exercise Testing Recommendation for Diagnostic Testing: Exercise Testing for Chronic Primary MR Referenced studies that support the recommendation are summarized in Online Data Supplement 28. 