Clicks due to Swan-Ganz catheter.

Nonejection systolic and diastolic clicks appeared when a Swan-Ganz catheter was positioned in the proximal portion of the right pulmonary artery. The clicks disappeared on inflation of the catheter's balloon. Initial impressions included secondary prolapse of the mitral leaflets, an accentuated third heart sound, and the exposure of an occult opening snap. These high-frequency sounds are thought to be generated by the forward and backward movement of the catheter against either the proximal portion of the pulmonary artery or the right ventricular outflow tract or by a whipping action of the catheter itself.