Reperfusion Injury, Myocardial

The goal of this observational study is to investigate the ability of the SpectroCor Tissue Oxygenation Monitor and its accessory SpectroCor Sensor to observe and monitor changes in cardiac oxygen availability in pediatric patients during open-heart surgery. Patients of less than 18 years old who, and whose guardian(s), when applicable according to national legislation, have signed the informed consent, can participate in the study. The primary hypothesis is that the SpectroCor Tissue Oxygenation Monitor and its accessory SpectroCor Sensor can detect myocardial oxygen availability in pediatric open-heart surgery patients. It is expected that the detected tissue oxygenation timely correlates with procedures affecting myocardial perfusion and other clinical parameters during the operation. The secondary hypothesis is that the SpectroCor Tissue Oxygenation Monitor and its accessory, the SpectroCor Sensor, are safe to use, and their usability is acceptable. No comparison group is included in the study. The devices are used by the study investigators during open-heart surgery to collect myocardial tissue spectrometer data from the pediatric population to validate and potentially further develop the monitor and its accessory, the sterile sensor. The follow-up period for each participant ends with discharge from the hospital. No data (such as questionnaires) are obtained directly from the study participants.

A heart attack (myocardial infarction) occurs when an artery supplying blood to the heart is suddenly blocked resulting in damage to the heart muscle. Patients presenting to hospital with a heart attack undergo an immediate angiogram (x-ray of the arteries in the heart) and are usually treated immediately with a balloon and stent to open their blocked artery. This procedure is called "primary percutaneous coronary intervention" (or primary PCI for short). An angiogram is a routine procedure that involves insertion of fine plastic tube (catheter) into either the groin or wrist under local anaesthetic. The tube is passed into the artery in the heart and X-ray pictures are taken to find out if the arteries are blocked. Blocked arteries can usually be opened by passing a small balloon into the artery, via the fine plastic tube followed by placement of a stent (a fine metal coil) into the artery to prevent it from blocking again. Although this treatment is very successful, it can result in damage to the heart muscle when the artery is opened. Cooling the entire body has been shown to reduce heart muscle damage during heart attacks in some patients but not in others; however, it is uncomfortable due to the shivering, expensive and can result in delays in opening the blocked artery. The investigators are conducting a series of research studies to find out if cooling the heart muscle directly through the catheter being used for the normal primary angioplasty treatment using room temperature may be effective in preserving heart muscle, without the shortcomings of entire body cooling. The investigators have already published an initial series of ten cases in which this treatment appeared to be feasible without causing significant clinical problems. The present study is a pilot study designed to assess the rate of patient recruitment and feasibility of this new treatment while exploring some detailed outcomes measuring the restoration of blood flow within the coronary artery at the end of the procedure. Ultimately if the present pilot study is successful, the investigators plan to go on to undertake a much larger randomised outcome study to determine definitively whether this treatment can help reduce heart attack size.