Cross-clamp fibrillation
Cross-clamp fibrillation (XCF) involves cross-clamping the aorta and inducing ventricular fibrillation, to allow the heart to continue to beat during vessel occlusion. A 2019 comparative study on XCF and cardioplegia in patients undergoing CABG, reviewed 3,340 XCF patients to measure survival outcomes and post-operative complications(38).  Their results showed that when compared to cardioplegia, XCF reduced cases of atrial arrhythmias, post-operative inotropic use and conferred a mean survival advantage(38).  However, there was no reported difference in mortality between the two procedures(38).
Glucose-insulin-potassium cardioplegia 
The use of a glucose-insulin-potassium (GIK) infusion was first detailed in 1962 by Sodi-Pallares et al. where it was used to treat acute myocardial infarction(39). Its mechanism of cardioprotection has been extensively reviewed and studies indicate that insulin plays the key role by targeting the the reperfusion injury salvage (RISK) pathway, which plays a role in reducing IRI(40). In 2002, the Insulin Cardioplegia Trial failed to demonstrate a significant difference in post-operative outcomes between patients receiving insulin solutions versus those in the placebo group in CABG surgery(41). However, since then a randomised-control trial by Ellenberger et al. in 2018 researched GIK effects on patients undergoing on-pump heart surgery. They reported that GIK was associated with better left systolic ventricular function after weaning off bypass, reduced cardiovascular and respiratory complications, and shorter ICU stays compared with saline(42).