title: Evaluation of peak pressure gradients in patients after melody valve implantation: a comparison of cardiac catheterization and doppler echocardiography.
abstract: OBJECTIVE
  The aim of this study was to determine and quantify the relationship between Doppler echocardiography and cardiac catheterization measurements of the peak right ventricle-pulmonary artery (RV-PA) pressure gradient in patients within 24 hours of Melody valve implantation for treatment of a dysfunctional RV outflow tract (RVOT) conduit or bioprosthetic valve (BPV).
  
  
  BACKGROUND
  Patients with a dysfunctional RVOT conduit or BPV are now routinely treated percutaneously with implantation of a Melody valve. However, often the postimplantation catheter measurements of the RV-PA peak gradient do not match the postimplant echo-derived gradients obtained after completion of the procedure. Importantly, these echo gradients are commonly used to monitor patients after implantation over time.
  
  
  METHODS
  Medical records of 42 patients with Melody valve implantation were reviewed (men: 25/42; mean age: 22.4 ± 11.2 years; RVOT conduit: 23/42; BPV: 18/42; pulmonic stenosis: 6/42, pulmonic regurgitation: 3/42, both: 33/42).
  
  
  RESULTS
  The postimplantation RV-PA peak gradient measured by Doppler echocardiography (within 24 hours of valve implantation) was significantly higher than the measurements acquired by catheterization immediately following implantation (24.2 ± 16.3 mmHg vs. 11.6 ± 8.5 mmHg, P < 0.0001). The relationship showed a moderate-strong correlation (r = 0.65, P < 0.0001) with regression analysis suggesting a linear association in both directions (echo gradient = 1.24 × cath gradient + 9.8, P<0.0001 vs. cath gradient = 0.34 × echo gradient + 3.4, P<0.0001).
  
  
  CONCLUSIONS
  The Doppler echocardiography-derived RV-PA peak gradient within 24 hours of valve implantation is predictably higher than the catheter measured peak gradient immediately following valve implantation. A regression equation was derived to define this important relationship.
authors.affiliation: Ahmanson/UCLA Adult Congenital Heart Disease Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Brenton S
authors.initials: BS
authors.lastname: Bauer
authors.affiliation: Ahmanson/UCLA Adult Congenital Heart Disease Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Sybil
authors.initials: S
authors.lastname: Zachariah
authors.affiliation: Ahmanson/UCLA Adult Congenital Heart Disease Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Daniel
authors.initials: D
authors.lastname: Levi
authors.affiliation: Children's Heart Center, Las Vegas, Nevada.
authors.forename: Abraham
authors.initials: A
authors.lastname: Rothman
authors.affiliation: Children's Heart Center, Las Vegas, Nevada.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Galindo
authors.affiliation: Ahmanson/UCLA Adult Congenital Heart Disease Center, David Geffen School of Medicine at UCLA, Los Angeles, California.
authors.forename: Jamil A
authors.initials: JA
authors.lastname: Aboulhosn
mesh_terms: D000293:Adolescent; D000328:Adult; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D015150:Echocardiography, Doppler; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016896:Treatment Outcome; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000601:surgery*; D055815:Young Adult
keywords: adult congenital heart disease; catheterization; conduit dysfunction; echocardiography; percutaneous transcatheter valve replacement