Why do aortic dissection and mitral valve prolapse occur in Marfan syndrome?

Marfan syndrome is a genetic disorder that affects the body's connective tissues, which provide support to various structures in the body, including the heart, blood vessels, and valves. The underlying issue in Marfan syndrome is a deficiency in fibrillin-1, a protein that is crucial for the proper formation and maintenance of connective tissue. This defect leads to structural weaknesses in the tissues that comprise the aorta and the mitral valve, making these structures predisposed to problems such as aortic dissection and mitral valve prolapse.

Aortic dissection occurs when the connective tissue in the aorta is weakened, allowing the layers of the aorta to separate (dissect) under pressure, which can lead to life-threatening conditions. Similarly, mitral valve prolapse occurs when the mitral valve's connective tissues are abnormal, resulting in the valve leaflets not being able to close properly. This can lead to regurgitation and other complications.

In this context, a connective tissue disorder is the fundamental cause of both aortic dissection and mitral valve prolapse in individuals with Marfan syndrome, making this the correct response to the question. The other options, such as aortic valve calcification, hypertrophic cardiomyopathy, and coronary artery disease