What are the cardiovascular complications, particularly those involving the aorta and other major blood vessels, in individuals with Marfan syndrome?

Cardiovascular Complications of Marfan Syndrome

Virtually every patient with Marfan syndrome will develop aortic disease at some point during their lifetime, with progressive aortic root dilatation leading to dissection or rupture being the primary cause of death. 1

Aortic Complications

Aortic Root Aneurysm and Dissection

• Aortic root dilatation occurs in 60-80% of patients and represents the most life-threatening cardiovascular complication, with Type A dissection being the most common presentation. 1
• The aortic root at the sinuses of Valsalva is the primary site of pathology, though dilatation can extend to the ascending aorta and aortic arch. 1
• Approximately 15% of patients experience dissection at aortic diameters less than 5.0 cm, emphasizing that even modest dilatation carries significant risk. 1
• The severity of disease correlates with both the degree and length of aortic dilatation—dilatation limited to the sinuses of Valsalva has a less malignant prognosis than extension to the aortic arch. 1

Type B Dissection and Descending Aorta

• A subset of patients present with Type B dissection involving the descending thoracic aorta, which carries a particularly poor prognosis. 1
• Other segments of the aorta beyond the root may also dilate, requiring comprehensive imaging of the entire aorta. 1, 2
• After initial ascending aortic repair, 53% of patients require second surgeries for subsequent aneurysms or dissections at other sites, most commonly involving the descending thoracic aorta, demonstrating that Marfan syndrome affects the entire aorta. 3

Valvular Heart Disease

Mitral Valve Complications

• Mitral valve prolapse with regurgitation is the second most common cardiovascular manifestation, occurring significantly more frequently than in the general population. 1, 4
• Mitral regurgitation can lead to symptoms of left ventricular volume overload and contributes to overall cardiovascular morbidity. 1

Aortic Valve Complications

• Aortic regurgitation develops in approximately 50% of patients, resulting from distortion of the aortic valve cusps by the enlarged aortic root rather than primary valve pathology. 1, 5
• Severe aortic regurgitation increases hemodynamic stress on the aortic wall and accelerates disease progression. 6

Tricuspid Valve Involvement

• Tricuspid valve abnormalities, including regurgitation, can occur as part of the cardiovascular spectrum. 1, 7

Myocardial Dysfunction

• Left ventricular systolic and diastolic dysfunction occurs independent of valvular disease, attributed to primary contractile dysfunction from underlying microfibrillar defects affecting myocardial elastic properties. 4
• This myocardial involvement may become increasingly important as patients survive longer with improved medical and surgical treatments. 4

Pulmonary Artery Dilatation

• Dilatation of the main pulmonary artery occurs with significantly higher prevalence in Marfan patients compared to normal controls and should be assessed during cardiovascular evaluation. 4

Risk Factors for Catastrophic Events

High-Risk Features

• Aortic diameter >5.0 cm represents definite surgical indication due to markedly increased dissection risk. 6
• Rapid aortic growth rate ≥0.3 cm/year indicates higher risk requiring more frequent monitoring and earlier intervention. 6
• Family history of aortic dissection substantially increases risk even at smaller aortic diameters. 1, 6
• Aortic cross-sectional area to height ratio ≥10 cm²/m identifies patients at risk for dissection at smaller absolute diameters, particularly important in shorter patients. 1, 6

Pregnancy-Related Risks

• Pregnancy represents a period of significantly increased risk for aortic dissection and rupture, particularly during the third trimester and delivery, with aortic root diameter >40 mm identifying an especially high-risk group. 1, 6
• Dissection can occur even with normal aortic dimensions, making any woman with Marfan syndrome a high-risk pregnancy candidate. 1

Clinical Pitfalls

• Dissection may occur even with only mild aortic dilatation, making the rate of progression heterogeneous and unpredictable among individual patients. 1, 2
• Patients with aortic disease are typically asymptomatic until catastrophic complications occur, emphasizing the critical importance of surveillance imaging. 1
• The risk of dissection clearly increases with increasing aortic diameter, but no diameter threshold provides complete protection against this complication. 1, 2