Perfusion
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Comparative Study Retracted Publication
Treating pulmonary hypertension post cardiopulmonary bypass in pigs: milrinone vs. sildenafil analog.
Procedures using cardiopulmonary bypass (CPB) and aortic cross-clamping are associated with a variable degree of ischemia/reperfusion of the lungs, leading to acute pulmonary hypertension (PHT). The purpose of this study was to compare the effects of the sildenafil analog (UK343-664), a phosphodiesterase type V(PDEV) inhibitor, with milrinone, a PDE type III inhibitor, in a porcine model of acute PHT following CPB. After the pigs were anesthetized, pressure-tipped catheters were placed in the right ventricle and carotid and pulmonary arteries. ⋯ After administration of the drugs, mean pulmonary artery pressure decreased in all 3 groups; however, only in the sildenafil-analog group did pulmonary vascular resistance(PVR) decrease by 35%, from 820 to 433 dynes . cm . sec(-5) at 5 minutes (p<0.05), and continued to be decreased at 10 minutes by 26% (P<0.05). Pulmonary selectivity was demonstrated with sildenafil-analog, because there were no similar changes in systemic vascular resistance(SVR) and no significant changes in systemic hemodynamics. Sildenafil-analog, a PDEV inhibitor, shows a promising role for managing the PVR increases that occur following CPB.