To the Editor:-For minimally invasive cardiac surgery, the Endocoronary Sinus [trade mark sign] catheter (Heartport, Redwood City, CA) is placed via a percutaneous venous introducer and permits delivery of cardioplegic solution into the coronary sinus after the tip of the catheter is positioned in the coronary sinus. Abramson and Giannoti described right ventricular perforation associated with attempted placement of this catheter. We agree that rapid diagnosis and treatment is important in this situation; furthermore, we wish to remind clinicians of proper techniques for introduction that should minimize the incidence of the reported complication. The coronary sinus drains into the right atrium; thus, advancement of the catheter into the right ventricle is generally not necessary. Monitoring of distal tip pressure provides a direct indication should the catheter tip be advanced from the right atrium across the tricuspid valve. In this circumstance, prompt withdrawal of the catheter back into the right atrium is necessary for rapid placement of the catheter into proper position in the coronary sinus and should also minimize the possibility of the catheter tip contacting the wall of the right ventricle. Imaging with transesophageal echocardiography or fluoroscopy facilitates catheter placement. Familiarity with cardiac anatomy and physiology combined with appropriate interpretation of clinical data permit efficient and safe placement of this catheter, typically in approximately 5 min. 
Lawrence C. Siegel, M.D.
Vice President, Clinical Affairs; Heartport, Inc.; Redwood City, California; Clinical Associate Professor of Anesthesia; Department of Anesthesia; Stanford University School of Medicine; Stanford, California
(Accepted for publication December 7, 1998.)