- Meeting abstract
- Open Access
1109 Quantification of the orifice area of bioprostheses in aortic position by cardiovascular magnetic resonance
© von Knobelsdorff-Brenkenhoff et al; licensee BioMed Central Ltd. 2008
- Published: 22 October 2008
- Cardiovascular Magnetic Resonance
- Aortic Valve Replacement
- Steady State Free Precession
- Orifice Area
- Effective Orifice Area
Effective orifice area is a decisive parameter in patients' follow-up after aortic valve replacement (AVR) with bioprostheses and is usually calculated by continuity equation in transthoracic echocardiography (TTE). However, difficult sonic conditions after cardiac surgery in many patients obviate reliable quantification of the prosthetic orifice.
This is the first series to test the feasibility of Cardiovascular Magnetic Resonance (CMR) as an alternative non-invasive method to quantify the orifice area of bioprostheses.
CMR planimetry was feasible in 13 patients (76.5%) and not feasible in 4 (23.5%): Two patients with stented prosthesis had susceptibility artefacts due to the prosthetic alloy superposing the orifice area, in 2 patients turbulent transvalvular flow rendered image-quality non-diagnostic. Mean orifice area did not differ between TTE (1.78 ± 0.25 cm2) and CMR (1.74 ± 0.26 cm2; p = 0.42). Orifice areas by TTE and CMR correlated significantly (r = 0.75; p = 0.003). All 5 patients with patient-prosthesis mismatch in TTE, defined as an effective orifice area index ≤ 0.85 cm2/m2, also showed orifice areas ≤ 0.85 cm2/m2 in CMR planimetry.
CMR planimetry of the orifice area of bioprostheses in aortic position is feasible and shows a high degree of consistency towards standard calculation by continuity equation. This new approach might prove especially valuable in patients with poor acoustic windows.
This article is published under license to BioMed Central Ltd.