The aim of this study was to demonstrate that total hemodynamic evaluation of patients with aortic regurgitation can be performed on an outpatient basis by combining right heart catheterization with digital subtraction angiography (DSA). Thirteen patients with severe aortic regurgitation were catheterized as outpatients, without premedication. The pulmonary artery was entered percutaneously through the femoral vein. Cardiac output and stroke volume were measured by the indicator dilution method by injection into the inferior vena cava and sampling from the pulmonary artery. The regurgitant fraction was obtained by subtracting the indicator stroke volume from the angiographic left ventricular stroke volume. The following results are expressed as mean +/- SD. Ejection fraction (%) = 54 +/- 6; end diastolic volume index (ml) = 228 +/- 40; end systolic volume index (ml) = 198 +/- 51 and regurgitant fraction (%) = 59 +/- 7 while the pulmonary wedge pressure (mmHg) = 10 +/- 3. In 4 cases, comparison with recent catheterization data showed good agreement for all parameters (r = 0.90), except ejection fraction (r = 0.75). In conclusion, this simplified catheterization method using digital subtraction enables the procedure to be done on an outpatient basis. All essential hemodynamic data can be obtained by right heart catheterization.