Investigating the effect of melatonin on myocardial tissue when administered before cardiac surgery in adults.

Heart disease is the leading cause of death worldwide. The only way to lessen the detrimental effects on the heart during oxygen poor circumstances is to re-introduce oxygen to the cells of the heart (by getting rid of the obstruction responsible for the problem). Re-introduction of blood flow and oxygen to cells that was oxygen poor however also results in damage to the cells. This is known as “reperfusion injury”, the medical world still doesn’t have a treatment option to eliminate reperfusion injury. The aim of this study is to investigate a new treatment option (melatonin) to lessen or eliminate the damage to the heart following reperfusion injury. Although we know that this treatment option is extremely effective in animals (it halved the size of heart attacks in rats), we still don’t have a clear answer to its role in humans. More research is required to determine how melatonin can benefit patients undergoing heart surgery. We thus hypothesize that preoperative, sublingual melatonin will have cardio-protective properties during reperfusion injury, and that the cardio-protection will be as a result of the anti-oxidant and anti-inflammatory effects associated with melatonin supplementation. The degree of cardio-protection, anti-inflammatory and anti-oxidative properties will be assessed by biomarkers (CRP and hsTnT levels found in blood samples). This study will be performed at two centres (Sir Charles Gairdner Hospital and Saint John of God, Subiaco) and is a prospective, randomized, double-blind, placebo-controlled, phase 2 study investigating the oral, preoperative administration of melatonin. Double-blind means that neither you nor your study doctor will know which treatment you are receiving. This research project has specifically been designed this way to make sure the researchers interpret the results in a fair and appropriate way and avoids study doctors or participants jumping to conclusions. However, in the event it is medically necessary your study doctor can find out which treatment you are receiving. The participants will be allocated into three study groups: The control group (receiving placebo with no active ingredients), the low dose melatonin group and the higher dose melatonin group.