Impact of Minimally Invasive Cardiac Surgery Versus Conventional OPEN Valve Surgery on Myocardial Protection

Background: Minimally invasive cardiac surgery (MICS) offers several advantages that can be particularly beneficial for older patients. However, nothing is currently known about the impact of MICS on myocardial protection. Thus, this study aimed to compare myocardial protection in valve surgery between patients who received MICS and those who underwent conventional open cardiac surgery (OPEN). Methods: We retrospectively included all adult patients (≥18 years) who received elective or urgent valve surgery in our department. We compared the peak value and area under the curve (AUC) of the high-sensitive troponin T (TnT) and creatine kinase muscle-brain type (CK-MB) concentrations during the first, second, and third 24 h period and the cumulative catecholamine dosages of adrenaline, noradrenaline, and enoximone at 72 h after removal of the aortic cross-clamp in patients who received valve replacement or reconstruction for MICS versus OPEN. Results: The peak TnT release in the first (p = 0.025) and second 24 h interval (p = 0.046), as well as the TnT AUC in the first 24 h (p = 0.024), were lower in the MICS group with reconstruction. The peak CK-MB release was relevantly lower in the first (p = 0.093) and third 24 h period (p = 0.067), as well as the CK-MB AUC between 48 and 72 h (p = 0.055). However, the peak release and AUC for TnT and CK-MB did not differ between MICS and OPEN in the replacement population. The noradrenaline dosage was lower (p = 0.023) for MICS in the replacement population. In the reconstruction population, the dosage of adrenaline (p = 0.036), noradrenaline (p = 0.043), and enoximone (p = 0.012) was lower in the MICS group than in the OPEN group. Conclusion: In addition to known factors of myocardial protection, such as ischemia time and cardioplegia, MICS seems to promote improved myocardial protection during valve reconstruction, while the postoperative catecholamine requirement is reduced after valve reconstruction and replacement. These additional benefits of MICS might be especially advantageous for old and frail patients undergoing cardiac surgery.