Barlow disease (BD) is a common cause of mitral insufficiency. In 2012 the University Hospital of Basel started to perform a simplified mitral valve repair technique in BD just by implanting an annuloplasty-ring. It is hypothesized that the major mechanism of the valvular insufficiency in Barlow disease is a deformation of the left ventricle and the posterior mitral annulus, causing its aberrant displacement during the systole towards posterior and basal and thus impairing the coaptation of the leaflets. This prospective individual MRI study is to investigate the ventricle and the mitral annulus pre- and postoperatively for detailed analysis.

Inclusion Criteria:

• identified Barlow disease suffering from significant mitral insufficiency with indication to surgery

Exclusion Criteria:

• Active endocarditis or any other etiology of mitral insufficiency else than Barlow disease
• Inability to perform a cardiac MRI (e.g., metallic implants, claustrophobia)
• Pregnancy
• Inability to give consent

Patients referred to cardiac surgery clinic (University Hospital Basel) through cardiologist meeting the inclusion criteria based on the medical history, clinical and echocardiographic findings.