title: Declining cardiopulmonary exercise capacity is not associated with worsening systolic systemic ventricular dysfunction in adults with transposition of great arteries after atrial switch operation.
abstract: OBJECTIVE
  Cardiopulmonary exercise capacity is often reduced in patients with transposition of the great arteries after atrial switch operation. Reduced exercise capacity may be caused by deterioration of systemic right ventricular function over time. This study analyzed serial changes in systemic right ventricular function and cardiopulmonary exercise capacity in young adults with transposition of the great arteries after atrial redirection surgery.
  
  
  METHODS
  Twenty-one patients (37% female, mean age 23.2 ± 3.3, mean age at surgery 12.8 ± 14 years) with transposition of the great arteries after atrial switch operation were included in this study. Patients were followed up for a mean period of 39.6 ± 13.1 months. Exercise capacity expressed as peak VO2 max, systemic right ventricular function and subpulmonary left ventricular function assessed by cardiac magnetic resonance imaging and NT-proBNP levels were obtained at baseline and follow-up. Changes in peak VO2 max were correlated to changes in cardiac magnetic resonance imaging and NT-proBNP levels.
  
  
  RESULTS
  Baseline peak VO2 max decreased significantly (28.31 ± 5.80 mL/kg/min vs. 25.17 ± 5.71 mL/kg/min, P = .005) on follow-up. Cardiac magnetic resonance imaging parameters of systemic right ventricular ejection fraction as well as subpulmonary left ventricular ejection fraction remained unchanged (44.68 ± 6.59% vs. 45.65 ± 9.60%, P = .54, 60.18 ± 6.29% vs. 61.52 ± 5.30%, P = .35). NT-proBNP levels did not increase (211.7 ± 85.7 ng/mL vs. 261.2 ± 182.2 ng/mL, P = .16).
  
  
  CONCLUSIONS
  After atrial switch operation for transposition of the great arteries we observed a declining functional exercise capacity. This was not associated with worsening systemic right ventricular function, suggesting that other factors are contributing to the decline in physical exercise capacity.
authors.affiliation: Clinic for Cardiology and Angiology, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Roentgen
authors.forename: Mareike
authors.initials: M
authors.lastname: Kaan
authors.forename: Oktay
authors.initials: O
authors.lastname: Tutarel
authors.forename: Gerd Peter
authors.initials: GP
authors.lastname: Meyer
authors.forename: Mechthild
authors.initials: M
authors.lastname: Westhoff-Bleck
mesh_terms: D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005858:Germany; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010101:Oxygen Consumption; D010446:Peptide Fragments / Q000097:blood; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014188:Transposition of Great Vessels / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D018497:Ventricular Dysfunction, Right / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right; D055815:Young Adult
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Brain Natiuretic Peptide; Cardiovascular Magnetic Resonance; Exercise Capacity; Mustard Procedure; Systolic Function; Transposition of Great Arteries