title: Endothelin inhibitors lower pulmonary vascular resistance and improve functional capacity in patients with Fontan circulation.
abstract: To evaluate the effects of endothelin inhibitors (ERAs) on hemodynamic and functional parameters in patients post-Fontan procedure with high pulmonary vascular resistance (PVR).
  
  
  
  Among our cohort of patients with Fontan circulation, 8 children, 8 adolescents, and 8 adults had PVR ≥2 WU*m2. These patients were treated with ERAs (minors with bosentan, adults with macitentan) and reevaluated after 6 months. Pre- and posttreatment hemodynamic variables were assessed by cardiac catheterization. Functional capacity was evaluated by cardiopulmonary exercise testing (CPET). Our primary endpoint was to obtain a reduction of PVR; the secondary endpoint was to obtain an improvement of functional capacity.
  
  
  
  Under treatment, New York Heart Association class improved for adolescents and adults. PVR decreased (P = .01) in all groups: in children from the median value 2.3 (interquartile range 2.0-3.1) to 1.9 (1.4-2.3) WU*m2, in adolescents from 2.3 (2.1-2.4) to 1.7 (1.4-1.8) WU*m2, and in adults from 2.8 (2.0-4.7) to 2.1 (1.8-2.8)WU*m2. In 71% of patients, PVR fell to less than 2 WU*m2. Cardiac index increased in adolescents from 2.6 (2.4-3.3) to 3.6 (3.4-4.3) L/min/m2, P = .04, and in adults from 2.1 (2.0-2.3) to 2.8 (2.3-4.7) L/min/m2, P = .03. CPET showed that only adolescents displayed a significant functional improvement. Anaerobic threshold improved from 17 (13-19) to 18 (13-20) mL/kg/min, P = .03; oxygen consumption and VO2max increased from 1.3 (1.0-1.6) to 1.7 (1.1-1.9) L/min, P = .02 and from 25 (21-28) to 28 (26-31) L/min, P = .02, respectively. Oxygen pulse increased from 7.9 (5.7-10.4) to 11.2 (8.2-13.0) L/beat, P = .01.
  
  
  
  This is the first study that assesses by cardiac catheterization and CPET the effects of ERA in patients with Fontan circulation with increased PVR. These results suggest that ERAs might provide most pronounced hemodynamic and functional improvement in adults and adolescents.
authors.affiliation: Division of Pediatric Cardiology, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy. Electronic address: gagnoletti@cittadellasalute.to.it.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Agnoletti
authors.affiliation: Division of Pediatric Cardiology, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Gala
authors.affiliation: Division of Pediatric Cardiology, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Ferroni
authors.affiliation: Division of Pediatric Cardiology, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bordese
authors.affiliation: Division of Statistics, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Appendini
authors.affiliation: Division of Cardiac Surgery, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Pace Napoleone
authors.affiliation: Division of Statistics, Citta' della Salute e della Scienza, Turin, ASL CN1, Saluzzo, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Bergamasco
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000077300:Bosentan / Q000009:adverse effects / Q000627:therapeutic use*; D006328:Cardiac Catheterization; D002648:Child; D065128:Endothelin Receptor Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D018729:Fontan Procedure / Q000009:adverse effects; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D011651:Pulmonary Artery / Q000187:drug effects* / Q000503:physiopathology; D011652:Pulmonary Circulation / Q000187:drug effects*; D011743:Pyrimidines / Q000009:adverse effects / Q000627:therapeutic use*; D020127:Recovery of Function; D013449:Sulfonamides / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D014655:Vascular Resistance / Q000187:drug effects*; D055815:Young Adult
chemical_list: D065128:Endothelin Receptor Antagonists; D011743:Pyrimidines; D013449:Sulfonamides; D000077300:Bosentan; C533860:macitentan
keywords: Fontan circulation; congenital heart disease; hemodynamics; pulmonary hypertension