Predictors of Late-Onset Atrial Fibrillation Following Isolated Mitral Valve Repairs in Patients With Preserved Ejection Fraction.
BACKGROUND
We sought to determine the incidence of and risk factors for late-onset atrial fibrillation (LOAF) in patients with preserved ejection fractions undergoing mitral valve repair


METHODS
We included patients undergoing isolated mitral valve repair (MVR) for degenerative disease between 1997-2014 at our institution with EF ≥60%. Patients who had AF preoperatively were excluded from the final analysis. Our primary outcome, LOAF, was defined as AF occurring after discharge following MVR (≥9 days).


RESULTS
223 patients were included in the study with a mean follow-up of 4.8 ± 4.6 years. A total of 25 patients developed LOAF, and freedom from LOAF was 93.9% at one year, and 87.3% at five years. Patients developing LOAF were of similar mean age (58 vs. 63 years in controls, p = 0.08) and had similar preoperative comorbidities, but did show a trend toward larger left atrial diameter (5.1 vs. 4.7 cm, p = 0.11). After risk adjustment with Cox regression analysis, only increasing left atrial size was associated with LOAF (HR 1.63, p = 0.04). On follow-up, 29 patients (10.8%) developed moderate or greater mitral regurgitation at a mean of 2.2 years. Using a mixed-effects model, we were unable to detect an association between recurrent mitral regurgitation following MVR and LOAF (OR 1.36, p = 0.42).


CONCLUSIONS
LOAF occurs in about 13% of preserved ejection fraction patients undergoing MVR by five years. Increasing left atrial diameter is an independent predictor of LOAF. Concomitant anti-arrhythmic procedures may warrant further investigation in patients with preserved ejection fraction and enlarged left atria undergoing MVR. doi: 10.1111/jocs.12774 (J Card Surg 2016;31:486-492).
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
J Trent
JT
Magruder
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Sarah
S
Collica
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Stephen
S
Belmustakov
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Todd C
TC
Crawford
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Joshua C
JC
Grimm
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Duke E
DE
Cameron
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
William A
WA
Baumgartner
Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University, Baltimore, Maryland.
Kaushik
K
Mandal
D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000601:surgery*; D011183:Postoperative Complications; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology*; D013997:Time Factors; D014481:United States / Q000453:epidemiology