Marfan syndrome (MFS) is an inherited connective tissue disease which frequently involves the cardiovascular system. The heart can be affected since valvular regurgitation is a common complication. However, there is still debate whether a primary cardiomyopathy exists. Our aim was to evaluate the existence of a Marfan‐related cardiomyopathy using cardiovascular magnetic resonance.

We retrospectively evaluated 68 consecutive adult patients with no cardiovascular surgery or significant valvular regurgitation. Left ventricular and right ventricular volumes, ejection fraction, and mass were estimated and compared with published data on a healthy control population. Patients were also assessed for heart failure, aortic dimensions, and valve disease.

One quarter (25.0%) of Marfan patients had reduced left ventricular ejection fraction (LVEF), with 25.0% having increased left ventricular end‐diastolic and 30.8% having increased end‐systolic volumes. The right ventricular ejection fraction was reduced in 10.3%, with increased right ventricular end‐diastolic volumes in 11.8% and increased end‐systolic volumes in 13.2%. On univariate analysis, no association was found between reduced LVEF and age, gender, indexed aortic dimensions, presence of mitral valve prolapse, or valve regurgitation.

This study supports the existence of a primary cardiomyopathy in a subgroup of Marfan patients. The biventricular enlargement and dysfunction is usually mild, asymptomatic, and independent from other cardiovascular manifestations. Further studies are needed to assess underlying causes and natural history of this condition. Routine monitoring and treatment in MFS may need to be tailored not only to prevent aortic root expansion but also to support myocardial function.