FEASIBILITY STUDY OF A DIRECT ENDO-AORTIC CLAMP BALLOON FOR MICS -ESTABLISHMENT OF BALLOON FIXATION DURING CPB

Abstract

Objective: MICS (Minimally Invasive Cardiac Surgery) has recently become an important concept in cardiac surgery. As the Heartport® port-access system under fluoroscopy is complicated, we developed a balloon which can be directly inserted easily and safely into the ascending aorta, and measured the balloon and perfusion pressure of CPB for preventing migration. Methods: We performed CPB with the balloon in twelve dogs (20 kg). Thoracotomy was performed, the ascending aorta was confirmed, and the outer diameter was measured. We cannulated into the femoral artery and into the right atrium for the CPB, inserted a root cannula and then EAC balloon, and inflated the balloon while confirming the internal pressure of the balloon. Then, the position of the balloon was confirmed while paying attention to systemic pressure and root pressure, and cardioplegia was injected. The pump pressure was progressively changed (50 mg, 80 mg, 90 mg), each balloon pressure was measured three times during one hour, and migration of the balloon was estimated. In addition, the histology at the fixed part of the balloon of the aorta was reviewed. Results: At the balloon pressure of 300–400 mmHg, the balloon migrated more than 100 mmHg. In all dogs, the balloon was inserted into the best position without fluoroscopy, and there was almost no histological difference between the endo-aortic clamp balloon compared with an extra-aortic clamp balloon. Conclusions: A new balloon was developed which can be easily and safely used, and which has potential for use in children.