1125 AN UNDER-RECOGNIZED CAUSE OF VENTRICULAR ARRHYTHMIAS AND SUDDEN CARDIAC DEATH: A CASE REPORT

Abstract

Abstract Mitral annular disjunction (MAD) is a structural abnormality which is commonly seen in patients with myxomatous mitral valve disease and mitral valve prolapse. MAD is a marker of severe disease including a higher need for mitral valve intervention and more arrhythmic events, which can be a cause of sudden cardiac death (SCD). A 72-years-old man with several cardiovascular risk factors (hypertension, diabetes mellitus, obesity, previous smoking, family history of cardiovascular diseases, chronic kidney disease) experienced two pre-syncopal episodes. Therefore, he was referred to a 24-hour Holter EKG that showed a non-sustained ventricular tachycardia (VT). A transthoracic 2D echocardiogram evidenced a mitral valve prolapse with mild regurgitation, normal left and right heart dimensions and function. Elective coronary angiography was performed to rule out an ischemic aetiology of ventricular arrhythmias (multiple cardiovascular risk factors and strong familiarity for coronary artery disease). The coronary angiography revealed a stenosis of 30% of left anterior descending artery and an intermediate stenosis of right coronary artery. A myocardial perfusion scintigraphy was performed to evaluate the intermediate coronary stenosis. The scintigraphy showed numerous focal perfusion abnormalities non indicative for coronary disease but rather for a degenerative or inflammatory disease. Indeed, we decided to perform a cardiac magnetic resonance (CMR). The CMR revealed a MAD with detachment of the root of the mitral annulus from the postero-lateral ventricular myocardium during systole, without areas of myocardial fibrosis evidenced by late gadolinium enhancement (LGE). Factors for high risk of SCD, such as fibrosis affecting the infero-basal left ventricle free wall or the papillary muscles, family history of SCD, personal history of complex ventricular arrhythmias, were not represented in our case. Therefore, we opted for a medical therapy with beta-blockers and a careful follow-up. MAD is an under-recognized cause of ventricular arrhythmias and SCD, generally associated to mitral valve prolapse. Echocardiography and CMR can identify and quantify MAD. A comprehensive evaluation, including multimodality imaging and clinical history, is mandatory for risk stratification of SCD and for optimal treatment.