Mitral annular disjunction (MAD) is an abnormal atrial displacement of the mitral valve leaflet hinge point. MAD is gaining clinical importance for several studies reporting its association to mitral valve prolapse (MVP), complex ventricular arrhythmias and sudden cardiac death.

On the other hand, other studies found MAD as an extremely diffuse anatomical variant of mitral valve annulus without any pathological implication.

Cardiac Magnetic Resonance is the non-invasive gold standard for myocardial characterization, with the possibility of accurate anatomical and functional evaluation associated to the evaluation of focal and interstitial fibrosis, resulting useful in the identification of arrhythmic substrate and for patients risk stratification. Additionally, Cardiac Magnetic Resonance (CMR) was found to be superior to echocardiography not only in term of tissue characterization, but also in the identification of small MAD.

Therefore, in relation to the scarcity of data about MAD prevalence and pathological potential, we set a large multicenter retrospective study aimed to evaluate prevalence of MAD in patients submitted to CMR independently by the clinical suspicion, and to evaluate the association with prolapse and arrhythmias.

Multicenter retrospective study. All cardiac MRI study obtained during the first semester of 2019 will be screened in order to identify the presence and severity of MAD, it association to other myocardial condition such as bileaflet mitral valve prolapse, miltral regurgitation, curling, and focal and interstitial fibrosis at LGE and ECV evaluation.

Finally, the association between MAD and arrhythmias will be investigated.

Inclusion Criteria:

• Consecutive adult patients (age ≥18 years-old), submitted to Cardiac Magnetic Resonance independently by the clinical suspicions in the first 6 month of 2019 (from January to June 2019) that have signed an Informed Consent authorizing data collection for future retrospective clinical research protocols

Exclusion Criteria:

• Pediatric patients (age <18 years-old), cardiac devices (implantable devices), previous mitral valve surgery, lack of LGE images, lack of clinical information about presence of arrhythmias. The timeline was selected to avoid the impact of COVID-19 pandemic on CMR availability, scheduling, and findings.

Consecutive adult patients (age ≥18 years-old), submitted to Cardiac Magnetic Resonance independently by the clinical suspicions in the first semesterof 2019 (from January to June 2019)