MAD may serve as a new marker for outcomes in Marfan's Syndrome, JAMA.

Recently, mitral annular disjunction (MAD), has received particular interest as a potential marker or substrate for ventricular arrhythmia and sudden cardiac death (SCD). Demolder et al have now shown that MAD among patients with Marfan's syndrome (MFS) is associated with the occurrence of arrhythmic events, a higher need for mitral valve intervention, and, among patients with extensive MAD, more aortic events. Cardiac imaging for patients with MFS should thus consider the assessment of MAD as a potential marker for adverse outcomes. These findings were published recently in JAMA Cardiology.

The cardinal features of MFS occur in the cardiovascular, ocular, and skeletal organ systems. Owing to the difficulties in predicting outcomes among patients with MFS, there is an unmet need for additional prognostic indicators. Recently, mitral annular disjunction (MAD), defined as a separation between the mitral valve hinge point and the left ventricular (LV) myocardium, has garnered new attention for predicting cardiovascular outcomes related to ventricular arrhythmias and SCD.

The present study was aimed to define the prevalence of MAD and examine its association with cardiovascular outcomes and arrhythmia among patients with MFS. This retrospective, single-center cohort study included 142 patients with a diagnosis of MFS based on the revised Ghent criteria and a confirmed (likely) pathogenic variant in the FBN1 gene.

The presence of MAD was assessed by echocardiography, and the extent of MAD was categorized in tertiles. Outcomes included aortic events (aortic dissection or prophylactic aortic surgery), arrhythmic events (defined as sustained ventricular tachycardia or sudden cardiac death), and mitral valve surgery.

MAD was found in 34% and was associated with a higher need for mitral valve intervention, occurrence of arrhythmic events (defined as sustained ventricular tachycardia and sudden cardiac death), and, among patients with extensive MAD, more aortic events. In addition, ventricular arrhythmia, but not atrial arrhythmia, was more often observed among patients with MAD.

Aortic root z scores were higher among patients with MAD. Mitral annular disjunction distance was independent of age or BSA and showed no significant increase over time, possibly related to a slow progression rate and/or echocardiographic variability. Mitral valve prolapse is frequently observed among patients with MFS, suggesting a potential association between MAD and connective tissue alterations.

"Our results suggest that patients with MFS and significant MAD may require close clinical follow-up and Holter monitoring", noted the authors.

Thus, this study suggests that reporting on the presence and extent of MAD should be considered in the routine cardiac evaluation of patients with MFS as a potential marker for adverse outcomes.

SOURCE: JAMA Cardiology: doi:10.1001/jamacardio.2021.2312