title: Bileaflet Mitral Valve Prolapse and Risk of Ventricular Dysrhythmias and Death.
abstract: BACKGROUND
  Bileaflet mitral valve prolapse (BiMVP) is common among survivors of otherwise unexplained sudden cardiac death, but prognostic implications of BiMVP are unknown. This study evaluated whether patients with BiMVP are at higher risk for ventricular dysrhythmias, ICD placement, or death compared to controls with either single-leaflet mitral valve prolapse (SiMVP) or no mitral valve prolapse (MVP).
  
  
  RESULTS
  This retrospective, matched cohort study included 18,786 patients who underwent echocardiography at Mayo Clinic between June 1990 and September 2014. The study included three cohorts: BiMVP, SiMVP, and controls without MVP. We assessed rates of ventricular dysrhythmias, ICD placement, and all-cause mortality between groups. BiMVP was associated with higher rates of ventricular tachycardia compared to SiMVP and controls (adjusted HR 1.48 [1.14-1.92], P = 0.003 and 1.40 [1.04-1.88], P = 0.026, respectively); however, there were no statistically significant differences in rates of ventricular fibrillation/cardiac arrest or ICD placement between groups. BiMVP was associated with a lower rate of all-cause mortality compared to SiMVP and controls (adjusted HR 0.86 [0.79-0.94], P = 0.0008, and 0.55 [0.50-0.60], P < 0.0001, respectively).
  
  
  CONCLUSIONS
  Although BiMVP is associated with ventricular tachycardia, it is not associated with an increased risk of cardiac arrest/ventricular fibrillation or ICD implantation and is, paradoxically, associated with a better survival compared to SiMVP or matched controls. The findings suggest that, despite its association with ventricular tachycardia, BiMVP in the absence of other risk factors does not seem to portend a poor prognosis at the population level.
authors.affiliation: Department of Medicine, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Nordhues
authors.affiliation: Department of Medicine, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Konstantinos C
authors.initials: KC
authors.lastname: Siontis
authors.affiliation: Division of Biostatistics, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Scott
authors.affiliation: Division of Cardiovascular Diseases, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Vuyisile T
authors.initials: VT
authors.lastname: Nkomo
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.|Division of Cardiovascular Diseases, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.|Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Ackerman
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.|Division of Cardiovascular Diseases, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Asirvatham
authors.affiliation: Division of Cardiovascular Diseases, Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Noseworthy
mesh_terms: D017677:Age Distribution; D015984:Causality; D015331:Cohort Studies; D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D008945:Mitral Valve Prolapse / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control
keywords: bileaflet mitral valve prolapse; implantable cardioverter-defibrillator; mitral valve prolapse; sudden cardiac death; ventricular fibrillation; ventricular tachycardia