Hemodynamic Changes Associated with Injection of Angiocardiographic Contrast Medium in Assessment of Valvular Lesions

Measurements of flow and pressures related to the left heart were made on 21 patients immediately prior to and at intervals of 2 and 4 minutes after angiocardiography. These patients had normal mitral valves (group 1), mitral incompetence (group 2), or mitral stenosis (group 3). There was an increase in left ventricular end-diastolic pressure accompanied by an increase in "pulmonary artery wedge" (PA wedge) pressure in all patients. Patients with mitral valve disease generally develop higher PA wedge pressures; those with mitral stenosis develop, in addition, significantly increased mean diastolic and end-diastolic gradients across the mitral valve. These increased gradients in mitral stenosis are due to increased flow across the mitral valve, which results from a combination of increased cardiac output and decreased diastolic filling time. Diagnostic angiocardiography affords an opportunity of observing the effects of valve lesions at a higher flow rate and is particularly useful in those patients with normal PA wedge pressure and small gradients initially.