Safety and Feasibility of Hyperkalemic Cardioplegia With Diazoxide in Cardiac Surgery (CPG-DZX) Trial

Safety and Feasibility of Hyperkalemic Cardioplegia With Diazoxide in Cardiac Surgery (CPG-DZX) Trial

This study aims to confirm the safety and efficacy of diazoxide as an additive to hyperkalemic cardioplegia in patients undergoing cardiac surgery with cardiopulmonary bypass. The investigators hypothesize that diazoxide combined with hyperkalemic cardioplegia provides superior myocardial protection and reduced myocardial stunning compared with standard cardioplegia alone. Thirty patients will receive treatment. Safety will be assessed by comparing mean arterial blood pressure measurements, glucose levels and incidence of adverse events between the two groups. Efficacy will be assessed by comparing right and left ventricular function in pre-operative vs post-operative transesophageal echocardiograms, need for mechanical circulatory support, ease of separation from bypass and Vasoactive Inotrope Score (VIS) between the two groups. The information gained could pave the way for the use of Katp (Potassium-atp) channel openers to prevent stunning, improve patient outcomes, and reduce health care costs related to myocardial stunning that requires inotropic and mechanical support following cardiac surgery.

This is a Phase I clinical trial. Thirty patients total will receive treatment (IV Diazoxide added to cardioplegia). Diazoxide will be added to the first dose of cardioplegia only. Subsequent doses of cardioplegia will not contain additives.

Inclusion Criteria:

• Age 18 years or older
• Scheduled for cardiac surgery with cardiopulmonary bypass and cardioplegic arrest
• Patient scheduled for elective cardiac surgery
• If female participant of childbearing potential, she must agree to and be able to use a highly effective method of birth control (eg, barrier contraceptives, hormonal contraceptives, intrauterine devices, or sexual abstinence) continuously for six days post- diazoxide dose

Exclusion Criteria:

• Patient with Diabetes Mellitus on sulfonylurea medications
• Scheduled for left ventricular assist device (LVAD) or heart transplant
• Left ventricular ejection fraction < 30%
• Pre-operative placement or planned use of mechanical circulatory support during surgery
• Allergy to Thiazide and its derivatives
• History of gout
• Patient is pregnant or breastfeeding
• Patients with seizure disorders controlled by diphenylhydantoin
• Patients with a history of cold agglutinins