Two cases are presented in which a pigtail catheter was entrapped by the chordae tendineae of the tricuspid valve during pulmonary arteriography. A technique for removal of the catheter from its entanglement by the chordae tendineae is described. Caution must be taken when advancing through the right ventricle a catheter that appears to be entrapped by the chordae tendineae. When such an entanglement occurs, measures to reduce the risk of rupturing a papillary muscle must be taken.