Abnormal Mechanics Relate to Myocardial Fibrosis and Ventricular Arrhythmias in Patients With Mitral Valve Prolapse

• Published in: Circulation. Cardiovascular imaging Vol. 16; no. 4; p. e014963
• Main Authors: Nagata, Yasufumi, Bertrand, Philippe B, Baliyan, Vinit, Kochav, Jonathan, Kagan, Ruth D, Ujka, Kristian, Alfraidi, Hassan, van Kampen, Antonia, Morningstar, Jordan E, Dal-Bianco, Jacob P, Melnitchouk, Serguei, Holmvang, Godtfred, Borger, Michael A, Moore, Reece, Hua, Lanqi, Sultana, Razia, Calle, Pablo Villar, Yum, Brian, Guerrero, J Luis, Neilan, Tomas G, Picard, Michael H, Kim, Jiwon, Delling, Francesca N, Hung, Judy, Norris, Russell A, Weinsaft, Jonathan W, Levine, Robert A
• Format: Journal Article
• Language: English
• Published: United States Lippincott Williams & Wilkins 01.04.2023
• Subjects: Arrhythmias, Cardiac - complications; Arrhythmias, Cardiac - etiology; Fibrosis; Humans; Mitral Valve Insufficiency - complications; Mitral Valve Insufficiency - etiology; Mitral Valve Prolapse - complications; Mitral Valve Prolapse - diagnostic imaging; Original; Papillary Muscles - diagnostic imaging; Prolapse; papillary muscles; magnetic resonance imaging; mitral valve prolapse; arrhythmia; echocardiography; fibrosis; mechanics
• ISSN: 1941-9651; 1942-0080; 1942-0080
• DOI: 10.1161/CIRCIMAGING.122.014963

The relation between ventricular arrhythmia and fibrosis in mitral valve prolapse (MVP) is reported, but underlying valve-induced mechanisms remain unknown. We evaluated the association between abnormal MVP-related mechanics and myocardial fibrosis, and their association with arrhythmia. We studied 113 patients with MVP with both echocardiogram and gadolinium cardiac magnetic resonance imaging for myocardial fibrosis. Two-dimensional and speckle-tracking echocardiography evaluated mitral regurgitation, superior leaflet and papillary muscle displacement with associated exaggerated basal myocardial systolic curling, and myocardial longitudinal strain. Follow-up assessed arrhythmic events (nonsustained or sustained ventricular tachycardia or ventricular fibrillation). Myocardial fibrosis was observed in 43 patients with MVP, predominantly in the basal-midventricular inferior-lateral wall and papillary muscles. Patients with MVP with fibrosis had greater mitral regurgitation, prolapse, and superior papillary muscle displacement with basal curling and more impaired inferior-posterior basal strain than those without fibrosis ( <0.001). An abnormal strain pattern with distinct peaks pre-end-systole and post-end-systole in inferior-lateral wall was frequent in patients with fibrosis (81 versus 26%, <0.001) but absent in patients without MVP with basal inferior-lateral wall fibrosis (n=20). During median follow-up of 1008 days, 36 of 87 patients with MVP with >6-month follow-up developed ventricular arrhythmias associated (univariable) with fibrosis, greater prolapse, mitral annular disjunction, and double-peak strain. In multivariable analysis, double-peak strain showed incremental risk of arrhythmia over fibrosis. Basal inferior-posterior myocardial fibrosis in MVP is associated with abnormal MVP-related myocardial mechanics, which are potentially associated with ventricular arrhythmia. These associations suggest pathophysiological links between MVP-related mechanical abnormalities and myocardial fibrosis, which also may relate to ventricular arrhythmia and offer potential imaging markers of increased arrhythmic risk.