Copulsation balloon for right ventricular assistance - Preliminary trials

Background-Options for management of acute right ventricular (RV) failure a re limited. This report describes preliminary testing of a temporary RV ass ist device that acts by direct compression of the RV. The system comprises a pancake-shaped silicone balloon (5 cm diameter) connected to a drive cons ole that delivers a 65-mL pneumatic pulse during cardiac systole. Methods and Results-Initial in vivo tests were performed on 6 pigs (weight, 41+/-4 kg). RV wall motion and stroke volume were monitored via transesoph ageal echocardiography. Acute RV failure was created by graded right corona ry ligation, which yielded a 63% reduction in RV stroke volume (39.9+/-8.2 to 14.7+/-1.9 mL; P<0.002). We secured the balloon over the RV free wall by attaching it to the edges of the opened pericardium. The sternum was then reapproximated, and data were collected with the device off and on (every b eat). Device placement had no deleterious effect on RV function. Balloon ac tivation returned RV stroke volumes to normal (37.8+/-9.2 mt) and increased mean pulmonary artery pressures from 13+/-2 to 16+/-3 mm Hg (P<0.01). RV c ompression did not induce or exacerbate tricuspid regurgitation. Mean aorti c pressure improved from postinfarction levels but did not return to normal . Conclusions-We conclude that the pulmonary circulation can be supported in the short term via cardiac compression and that balloon copulsation techniq ues for short-term RV failure should be tested in long-term models.