Combined endothelial and myocardial protection by endothelin antagonism enhances transplant allograft preservation.

Background: Endothelin is a potent inflammatory peptide associated with myocardial dysfunction, coronary vasculopathy, and reduced survival after cardiac transplantation. We hypothesized that endothelin antagonism during cardiac allograft storage would limit early endothelial dysfunction and improve myocardial performance after transplantation.

Methods: Porcine orthotopic transplantations (n = 16) were performed after 6 hours of ischemic storage.

Is profound hypothermia required for storage of cardiac allografts?

Background: Improved methods of cardiac allograft protection are required to expand the pool of potentially available organs and to enhance the recovery of grafts subjected to prolonged ischemia. We have previously demonstrated that limited coronary perfusion provided by donor blood harvested at the time of organ procurement can improve both metabolic and functional recovery after transplantation. In this study we evaluated the hypothesis that limited coronary perfusion may enable prolonged cardiac storage while avoiding the potentially detrimental effects of profound hypothermia.

Acute graded hypercapnia increases collateral coronary blood flow in a swine model of chronic coronary artery obstruction.

Objective: To evaluate the effect of acute hypercapnia on regional myocardial blood flow in a swine model of chronic, single-vessel coronary artery obstruction. Permissive hypercapnia is being used frequently in critical care settings. One possible detrimental effect of hypercapnia is the initiation of coronary "steal" in patients with coronary artery disease.

Donor blood perfusion improves myocardial recovery after heart transplantation.

Background: Improved methods of donor heart preservation may allow for prolonged storage and permit remote procurement. Previous attempts to use oxygenated perfusion circuits during storage have not gained widespread acceptance because they were either too impractical or complicated to use for remote harvest. We hypothesized that collection and perfusion of donor blood during prolonged storage may improve myocardial recovery.