The mitral annulus disjunction of mitral valve prolapse: Presentation and outcome

Abstract

To assess in MVP-patients, MAD prevalence, phenotypic characteristics and long-term outcome. A cohort of 595 (278 female, age 61 ± 16 years) consecutive patients with isolated MVP, comprehensive clinical, rhythmic, Doppler-echocardiographic and consistent MAD assessment, was examined. MAD prevalence, associated MVP-phenotype and outcome [survival, ventricular arrhythmias (VA)] were analyzed. To balance important baseline differences, we also propensity score matched patients with and without MAD (no-MAD). MAD presence was common (186 – 31%) in MVP, generally in younger patients and was not random but independently associated with severe myxomatous disease and larger left ventricle ( P ≤ 0.005). Age-matched-cohort survival after MVP diagnosis was not worse with MAD (10-year 93 ± 2% for no-MAD and 97 ± 1% for MAD, P = 0.4), even adjusted-comprehensively for MVP characteristics ( P = 0.8) and accounting for time-dependent mitral-surgery ( P = 0.6). During follow-up, 218 patients were diagnosed with VA post-30 days from MVP diagnosis (159 with ventricular tachycardia-VT). MAD was independently associated with higher risk of VA (adjusted-hazard-ratio 2.39[1.79–3.22]) and VT (2.79[1.98–3.94], both P < 0.0001). MAD link to VA persisted with time-dependent mitral-surgery (adjusted-hazard-ratio 2.25[1.65–3.01], P < 0.0001), strongly under medical-management (adjusted-hazard-ratio 2.91[1.95–4.35], P < 0.0001) but weakly post-mitral-surgery (adjusted-hazard-ratio 1.77[1.12–2.79], P = 0.01). This large cohort with MVP comprehensively characterized, shows that MAD is frequent at MVP diagnosis and strongly linked to advanced-myxomatous-degeneration. MAD presence is independently associated with long-term excess-incidence of VA and VT. However, within the first 10 years post-diagnosis MAD is not linked to excess-mortality and while reassurance should be provided from the survival point of view careful monitoring for arrhythmias is in order with MAD.