The hemodynamic effects and mechanism of action of XXXX in the treatment of @entity67 during left heart bypass.

@entity1169 @entity1707 @entity712 @entity64 @entity358 @entity661 @entity2224 @entity67
The efficacy of @entity358 ( @entity358 ) was evaluated in improving right ventricular (RV) output during left heart bypass for @entity712 . In 13 @entity1707 , a 40-ml balloon was positioned within a graft anastomosed to the pulmonary artery distal to the pulmonary valve, and left heart bypass was instituted from the left atrium to the carotid artery. @entity712 was produced by an infusion of @entity1169 (range, 25 to 78 mg). In this model, RV output decreased despite volume loading to a right atrial pressure of 15 mm Hg and atrioventricular sequential pacing at 100 beats per minute. Pulmonary artery balloon counterpulsation increased both RV output (from 519 +/- 76 to 1,117 +/- 110 ml/min; p less than 0.01) and RV @entity64 work (from 1.3 +/- 0.4 to 2.3 +/- 0.6 gm-m; p less than 0.01). Right atrial pressure decreased (from 15.5 +/- 0.9 to 10.7 +/- 1.0 mm Hg; p less than 0.01) in 8 of the @entity1707 studied during RV failure. In 5 @entity1707 , @entity2224 occurred without a stable model of RV failure, and there was no cardiac output before or after counterpulsation. The mechanism of action of @entity358 was studied by placing a flow probe around a large branch of the right pulmonary artery. During @entity67 caused flow through the pulmonary circulation, and ventricular systole resulted in filling of the graft. During @entity2224 , @entity661 and deflation produced only a to-and-fro movement of blood in the pulmonary artery branch without net forward flow.(ABSTRACT TRUNCATED AT 250 WORDS)
