What is often omitted in contemporary myocardial protections

Contemporary myocardial protection techniques commonly omit optimal strategies for protecting the heart during reperfusion, which is the phase when blood flow is restored to the tissue. We read with great interest the article: ‘Myocardial protection in cardiac surgery—hindsight from the 2020s’ by Mukharyamov et al. The authors reviewed the biochemical principles of ischaemia, reperfusion and cardioplegic extension of ischaemia tolerance and addressed the concepts of myocardial protection with ‘hindsight from the 2020s’. In light of rising patient risk profiles, minimizing surgical trauma and improving perioperative morbidity management become key today [1]. In this context we focused from a critical point of view on the comparison of different cardioplegic solutions and their delivery techniques, in particular: (i) on the role and relationship between the cardiac mass and volume of myocardial protection solution is a limitation that this review has not explored in detail and (ii) the perioperative echocardiography can detect aortic regurgitation (AR) that may interfere with the adequate delivery of cardioplegia solution to the myocardium during cardiac operation. The cardiac mass influences the volume administration of myocardial protection solution in cardiac surgery. Larger hearts may require increased volumes to ensure adequate distribution of the protective solution, while smaller hearts may need less. Tailoring the volume to the individual's cardiac mass through relative wall thickness formula with echocardiography helps optimize myocardial protection during surgery, supporting better outcomes and minimizing complications [2]. During valve surgery, the antegrade delivery of cardioplegic solution via the aortic root is the most utilized method for arresting the heart. However, in the context of moderate or severe AR, such antegrade method may not be effective, since most of the cardioplegia may go to the left ventricle. Rapid venting of the left ventricle through a vent catheter or squeezing of the left ventricle during the delivery of cardioplegic solution can be an effective option. Direct coronary cannulation is also possible, but it may result in late coronary ostial stenosis yet particular care should be taken in order to avoid mechanical trauma to the coronary arteries. Retrograde coronary sinus perfusion of cardioplegic solution may be an alternative technique in the presence of significant AR [3]. We ask the authors, congratulating them on their review, if according to their point of view these critical issues are limitations that we can control in the future through echocardiography to improve the quality in perfusion.

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