title: Cardiopulmonary exercise test in adults with prior Fontan operation: The prognostic value of serial testing.
abstract: BACKGROUND
  The purpose of the study was to determine the role of cardiopulmonary exercise test (CPET) indices in predicting cardiovascular adverse events (CAEs) in patients with Fontan palliation. CAE was defined as death or cardiac surgery.
  
  
  METHODS
  Retrospective review of adult Fontan patients who had treadmill CPET at Mayo Clinic, 1994-2013. Patients with loss of follow-up defined as ≥2years without clinical follow-up were excluded. The results of serial CPETs were reviewed, and patients with CPETs meeting the following criteria were selected for analysis: maximum effort on serial CPETs, minimum of 3-year interval between CPETs, and absence of CAE between CPETs.
  
  
  RESULTS
  A total of 145 patients met inclusion criteria for the study; age at baseline CPET was 24±3years; age at Fontan operation was 11±5years; and 91 (63%) were males. Baseline peak oxygen consumption (VO2) was 22.7±5.4ml/kg/min (63±11% predicted), peak heart rate was 135±31beats per minute, and oxygen saturation at peak exercise was 86±7%. Serial CPETs were performed in 71/145 patients (49%); mean duration between CPETs was 3.8±0.3years. The % predicted peak VO2decreased by 1.7±0.9 percentage points/year. CAE (deaths n=22; cardiac surgery n=45) occurred in 54/145 patients (37%) within 8±3years. Decline in % predicted peak VO2≥3 percentage points/year was the only predictor of 5-year risk of CAE (HR 1.86, 95% CI 1.11-3.48, P=0.02).
  
  
  CONCLUSIONS
  Serial CPET is prognostic of CAE in the adult Fontan population, and can be used to risk stratify these patients.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA. Electronic address: egbe.alexander@mayo.edu.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Egbe
authors.affiliation: Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Driscoll
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA.
authors.forename: Arooj R
authors.initials: AR
authors.lastname: Khan
authors.affiliation: Division of Cardiovascular Surgery, Mayo Clinic, Rochester, MN, USA.
authors.forename: Sameh S
authors.initials: SS
authors.lastname: Said
authors.affiliation: Department of Internal Medicine, Wayne State University/Detroit Medical Center, Detroit, MI, USA.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Akintoye
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA.
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Berganza
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA.
authors.forename: Heidi M
authors.initials: HM
authors.lastname: Connolly
mesh_terms: D000328:Adult; D018376:Cardiovascular Abnormalities / Q000601:surgery; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D018729:Fontan Procedure / Q000009:adverse effects* / Q000379:methods; D006339:Heart Rate; D006801:Humans; D000069451:Long Term Adverse Effects / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D010101:Oxygen Consumption; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D013997:Time Factors; D014481:United States
keywords: Adverse event; Cardiopulmonary exercise testing; Fontan; Oxygen consumption