Which type of cardioplegia may be less effective in the presence of calcified aorta?

Antegrade cardioplegia is often less effective in the presence of a calcified aorta due to several anatomical and physiological factors. Antegrade cardioplegia is typically delivered directly into the coronary arteries via cannulation of the aorta, relying on the aortic pressure to facilitate the flow of the cardioplegic solution into the myocardium.

In cases of a calcified aorta, the rigidity and narrowed lumens of the arterial vessels can impede the ability of the cardioplegic solution to flow freely into the coronary arteries. The calcification can create obstructions or areas of reduced compliance, making it difficult for the solution to effectively perfuse the myocardium, which is essential for achieving adequate cardiac protection during periods of ischemia.

Furthermore, the antegrade approach depends on a healthy, compliant vessel that can accommodate and distribute the cardioplegic fluid adequately. In contrast, retrograde cardioplegia, which is delivered through the coronary sinus, may bypass some of these obstacles and better deliver the protective solution to the heart muscle, even in the presence of a calcified aorta.

Understanding the implications of a calcified aorta on the efficacy of different cardioplegic methods is crucial for perfusionists to ensure optimal myocardial preservation