Continuous or intermittant retrograde cardioplegia during coronary bypass: A propensity score adjusted comparison

Introduction Continuous retrograde cardioplegia worsens surgeon’s vision while performing distal anastomosis in coronary artery bypass grafting operations. We investigated whether intermittent retrograde cardioplegia, which provides a bloodless surgical field by interrupting cardioplegia flow during distal anastomosis, poses a disadvantage in terms of myocardial protection. Methods This retrospective study was conducted in two different heart centres between January 2013 and July 2023. A total of 234 patients who underwent ≥2 target vessel revascularization under cardiopulmonary bypass were examined. Isothermic, potassium-enriched blood cardioplegia was used and induction was performed antegrade in all patients. In addition to antegrade, we routinely gave retrograde cardioplegia. Retrograde cardioplegia was applied continuously with the force of gravity in the continuous group ( n = 167), and intermittently with pressure in the intermittent group ( n = 167). Results The volume of cardioplegia solution administered was significantly higher in the intermittent group compared to the continuous group (4070 ± 760 mL vs 3190 ± 575 mL; p = 0.001). However, no significant differences were observed between the groups regarding postoperative clinical outcomes or early mortality rates. Conclusions Intermittent retrograde cardioplegia offers superior operative conditions by ensuring a bloodless surgical field and improved procedural comfort, while maintaining equivalent efficacy in myocardial protection compared with the continuous method.