Objectives: 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).
Conclusion: 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.
Keywords: adult congenital heart disease; catheterization; conduit dysfunction; echocardiography; percutaneous transcatheter valve replacement.
© 2014, Wiley Periodicals, Inc.