Background: Defending the heart against potential damage during cross-clamping is the most important and vital step to ensuring a successful surgical outcome(1). The creation of cardioplegia solutions was one of the major advances in cardiac surgery that allowed surgeons to conduct complicated surgical procedures to avoid myocardial injury (14). Treating cardioplegia at a cool temperature would be a significant factor in lowering myocardial metabolism. However, the reduction in myocardial metabolism due to hypothermia, compared with that achieved by diastolic arrest, is usually very negligible. Since Normothermias enzymatic and cellular processes work better (7). Owing to the propensity of the heart to resume electrical operation during normothermia, however, this must be administered consistently or only with short interruptions (4). Terminal warm blood cardioplegia (hot shot) is normally done just before the elimination of the aortic cross-clamp since it has been demonstrated that myocardial metabolism is increasing (23). Methods: A prospective controlled randomised study (200 hundred patients aged 40 to 65 years of both sexes underwent elective CABG pump surgery) will be included. They will be divided into three groups of patients: Group I:includes 100 Patients who received intermittent cold blood cardioplegia. Group II:includes 100 Patients who received intermittent warm blood cardioplegia with controlled reperfusion for 3 minutes before aortic unclamping. Study made from January, 2019 to August, 2020, at National Heart Institute.All patients were thoroughly evaluated preoperatively, intraoperatively, and postoperatively. Results: We hypothesized that in our patient cohort, warm blood cardioplegia could be as successful as or even better than the conventional antegrade cold blood cardioplegia. Patients were randomised into two similar blocks, each of which consisted of 100 patients, each of whom obtained one of the two cardioplegic solutions. Our analysis did not indicate a statistically important difference in the post-operative release of myocardial biomarkers (Troponin I) & CK in both classes. This finding did not significantly reflect the clinical outcome of our patient, which may indicate similar myocardial protection in primary low-risk CABG patients for both cold and warm blood cardioplegia. Conclusion: During the time of cardiac arrest, both methods tend to enable an equal and adequate approach for myocardial defence. To attain improved myocardial defence, warm blood cardioplegia needs a shorter administration interval. Therefore, the choice between one type of cardioplegia and the other remains at the discretion of the surgeon. The statistically minor variation found in the release of myocardial enzymes did not translate into distinct clinical results.
Randomized trial comparing intermittent antegrade warm blood cardioplegia with multidose cold blood cardioplegia for coronary artery bypass
