ATP—Sensitive Potassium Channel Opener Diazoxide Reduces Myocardial Stunning in a Porcine Regional With Subsequent Global Ischemia Model

Ana K. Velez, Eric Etchill, Katherine Giuliano, Sean Kearney, Melissa Jones, Jie Wang, Brian Cho, Mary Beth Brady, Jeffrey Dodd-O, Joseph M. Meyer, Jennifer S. Lawton

Research output: Contribution to journalArticlepeer-review

Abstract

BACKGROUND: ATP-sensitive potassium channels are inhibited by ATP and open during metabolic stress, providing endog-enous myocardial protection. Pharmacologic opening of ATP potassium channels with diazoxide preserves myocardial function following prolonged global ischemia, making it an ideal candidate for use during cardiac surgery. We hypothesized that diazoxide would reduce myocardial stunning after regional ischemia with subsequent prolonged global ischemia, similar to the clinical situation of myocardial ischemia at the time of revascularization. METHODS AND RESULTS: Swine underwent left anterior descending occlusion (30 minutes), followed by 120 minutes global ischemia protected with hyperkalemic cardioplegia±diazoxide (N=6 each), every 20 minutes cardioplegia, then 60 minutes reperfusion. Cardiac output, time to wean from cardiopulmonary bypass, left ventricular (LV) function, caspase-3, and infarct size were compared. Six animals in the diazoxide group separated from bypass by 30 minutes, whereas only 4 animals in the cardioplegia group separated. Diazoxide was associated with shorter but not significant time to wean from bypass (17.5 versus 27.0 minutes; P=0.13), higher, but not significant, cardiac output during reperfusion (2.9 versus 1.5 L/min at 30 minutes; P=0.05), and significantly higher left ventricular ejection fraction at 30 minutes (42.5 versus 15.8%; P<0.01). Linear mixed regression modeling demonstrated greater left ventricular developed pressure (P<0.01) and maximum change in ventricular pressure during isovolumetric contraction (P<0.01) in the diazoxide group at 30 minutes of reperfusion. CONCLUSIONS: Diazoxide reduces myocardial stunning and facilitates separation from cardiopulmonary bypass in a model that mimics the clinical setting of ongoing myocardial ischemia before revascularization. Diazoxide has the potential to reduce myocardial stunning in the clinical setting.

Original languageEnglish (US)
Article numbere7723
JournalJournal of the American Heart Association
Volume11
Issue number23
DOIs
StatePublished - 2022

Keywords

  • animals
  • cardiopulmonary bypass
  • diazoxide
  • heart arrest, induced
  • myocardial stunning
  • swine
  • ventricular function, left

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Fingerprint

Dive into the research topics of 'ATP—Sensitive Potassium Channel Opener Diazoxide Reduces Myocardial Stunning in a Porcine Regional With Subsequent Global Ischemia Model'. Together they form a unique fingerprint.

Cite this