title: Myocardial extracellular volume expansion and the risk of recurrent atrial fibrillation after pulmonary vein isolation.
abstract: OBJECTIVE
  This study tested whether myocardial extracellular volume (ECV) is increased in patients with hypertension and atrial fibrillation (AF) undergoing pulmonary vein isolation and whether there is an association between ECV and post-procedural recurrence of AF.
  
  
  BACKGROUND
  Hypertension is associated with myocardial fibrosis, an increase in ECV, and AF. Data linking these findings are limited. T1 measurements pre-contrast and post-contrast in a cardiac magnetic resonance (CMR) study provide a method for quantification of ECV.
  
  
  METHODS
  Consecutive patients with hypertension and recurrent AF referred for pulmonary vein isolation underwent a contrast CMR study with measurement of ECV and were followed up prospectively for a median of 18 months. The endpoint of interest was late recurrence of AF.
  
  
  RESULTS
  Patients had elevated left ventricular (LV) volumes, LV mass, left atrial volumes, and increased ECV (patients with AF, 0.34 ± 0.03; healthy control patients, 0.29 ± 0.03; p < 0.001). There were positive associations between ECV and left atrial volume (r = 0.46, p < 0.01) and LV mass and a negative association between ECV and diastolic function (early mitral annular relaxation [E'], r = -0.55, p < 0.001). In the best overall multivariable model, ECV was the strongest predictor of the primary outcome of recurrent AF (hazard ratio: 1.29; 95% confidence interval: 1.15 to 1.44; p < 0.0001) and the secondary composite outcome of recurrent AF, heart failure admission, and death (hazard ratio: 1.35; 95% confidence interval: 1.21 to 1.51; p < 0.0001). Each 10% increase in ECV was associated with a 29% increased risk of recurrent AF.
  
  
  CONCLUSIONS
  In patients with AF and hypertension, expansion of ECV is associated with diastolic function and left atrial remodeling and is a strong independent predictor of recurrent AF post-pulmonary vein isolation.
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Division of Cardiology, Department of Medicine, Cardiac MR PET CT Program, Division of Radiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Tomas G
authors.initials: TG
authors.lastname: Neilan
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Department of Medicine, Montreal Heart Institute, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Francois-Pierre
authors.initials: FP
authors.lastname: Mongeon
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Division of Cardiology, Department of Medicine, Cardiac MR PET CT Program, Division of Radiology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Ravi V
authors.initials: RV
authors.lastname: Shah
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Department of Internal Medicine, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
authors.forename: Otavio
authors.initials: O
authors.lastname: Coelho-Filho
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Siddique A
authors.initials: SA
authors.lastname: Abbasi
authors.affiliation: Division of Aging, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: John A
authors.initials: JA
authors.lastname: Dodson
authors.affiliation: Division of Nephrology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Ciaran J
authors.initials: CJ
authors.lastname: McMullan
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Bobak
authors.initials: B
authors.lastname: Heydari
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Gregory F
authors.initials: GF
authors.lastname: Michaud
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Roy M
authors.initials: RM
authors.lastname: John
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Ron
authors.initials: R
authors.lastname: Blankstein
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Michael
authors.initials: M
authors.lastname: Jerosch-Herold
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts. Electronic address: rykwong@partners.org.
authors.forename: Raymond Y
authors.initials: RY
authors.lastname: Kwong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D002306:Cardiac Volume; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D017115:Catheter Ablation / Q000379:methods*; D018450:Disease Progression; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D005110:Extracellular Space; D005260:Female; D005355:Fibrosis; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D010865:Pilot Projects; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence
keywords: AF; CI; CMR; ECG; ECV; HR; HTN; LA; LGE; LV; PVI; T(1) measurements; atrial fibrillation; cardiac magnetic resonance; confidence interval; electrocardiography; extracellular volume; hazard ratio; hypertension; late gadolinium enhancement; left atrial; left ventricular; myocardial fibrosis; pulmonary vein isolation