In a previous article, a left ventricular assist system (LVAS) with a percutaneous transseptal cannulation technique for easy application was described. This system was safe and efficient (maximum output >3 L/min) and fitted between the intraaortic balloon pumping and LVAS with thoracot-omy. But technical skill for placement was slightly complicated. The cannulation system has been improved. In the new system, the inlet cannula is initially used as a sheath introducer and is quickly inserted into the left atrium after transseptal puncture. The new inlet cannula is made of polyvinyl chloride (TM100, Toyobo, Co., Ltd., Osaka, Japan), which has excellent antithrombogenicity and low friction using a polyester plasticizer. The distal part is designed to be flexible with a spiral wire for easy manipulation. A sealing hub was installed to prevent bleeding at the proximal end. The simplicity and safety of the new system were examined in chronic animal experiments. The inlet cannula was placed into the left atrium within a few seconds after transseptal puncture. During 20 days of activation, there were no episodes of systemic or pulmonary embolism, although no anticoagulant was used. Under fluoroscopy, there was no thrombus formation around the cannula at removal. On the 14th day after removal, the puncture site of the septum had healed. This system is ready for clinical use and shows promise of satisfactory safety and manageability.
©1991 American Society of Artificial Internal Organs