Radionuclide methods of measuring the right ventricular (RV) ejection fraction (EF) provide noninvasive means of evaluating right-sided cardiac function at rest and exercise. This study compared 2 radionuclide methods with a cast-validated contrast angiographic method of RVEF analysis in 21 consecutive patients who underwent RV contrast ventriculography and gated equilibrium blood pool radionuclide ventriculography. Eleven subjects had gated first-pass radionuclide studies that were technically adequate for EF analysis. RVEF was calculated by different operators for the contrast and radionuclide methods. The close correlation of the contrast angiographic method with both equilibrium blood pool and first-pass radionuclide methods supports the use of the radionuclide techniques.