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[Hemodynamics after mitral valve replacement with Starr-Edwards, Björk-Shiley and Lillehei-Kaster protheses (author's
Insights
Mitral valve replacement prostheses can cause persistent hemodynamic abnormalities. The Björk-Shiley valve demonstrated superior hemodynamic performance compared to Starr-Edwards and Lillehei-Kaster valves, particularly during exercise.
Area of Science:
- Cardiovascular Surgery
- Biomedical Engineering
- Hemodynamics
Background:
- Persistent hemodynamic abnormalities after mitral valve replacement require further investigation.
- Understanding prosthesis performance is crucial for optimizing patient outcomes.
Purpose of the Study:
- To evaluate and compare the long-term hemodynamic performance of three different mitral valve prostheses: Starr-Edwards (SEM), Lillehei-Kaster (LKM), and Björk-Shiley (BSM).
- To assess the impact of valve type and size on hemodynamic parameters at rest and during exercise one year postoperatively.
Main Methods:
- A randomized study involving 50 patients who underwent mitral valve replacement.
- Hemodynamic parameters including pulmonary arterial pressure, left atrial pressure, cardiac index, and valve gradients were measured at rest and during exercise.
- Functional valve orifice area and ejection fraction were calculated for each prosthesis type.
Main Results:
- All prostheses exhibited some degree of stenosis, leading to increased pulmonary artery and left atrial pressures during exercise.
- The Björk-Shiley (BSM) tilting disc valves showed the most favorable hemodynamic results, likely due to their optimal internal-to-external diameter ratio.
- Starr-Edwards (SEM) prostheses exhibited consistent results, suggesting complete opening, but had significant pressure gradients due to small internal diameters.
- Lillehei-Kaster (LKM) pivoting disc valves demonstrated unexpectedly small functional valve areas, possibly from incomplete disc opening.
Conclusions:
- Prosthesis type significantly influences long-term hemodynamic function after mitral valve replacement.
- The Björk-Shiley valve appears to offer superior hemodynamic performance compared to Starr-Edwards and Lillehei-Kaster valves.
- Further research into valve design, particularly internal diameter and opening mechanics, is warranted to minimize hemodynamic abnormalities.
Abstract:
After mitral valve replacement hemodynamic abnormalities persist. These abnormalities were studied 1 year postoperatively. In 50 randomized patients; 15 with Starr-Edwards (SEM), 15 with Lillehei-Kaster (LKM) and 20 with Björk-Shiley (BSM) prostheses at rest and during exercise. Simultaneously were determined: pulmonary arterial pressure, left atrial pressure, left ventricular enddiastolic pressure, mean diastolic pressure gradient across the prostheses, cardiac index, stroke volume index, valve orifice area, and ejection fraction. The results show an important stenosis by the prostheses leading to high pressure increase in pulmonary artery and left atrium during excercise. This stenosis depends on valve size and type. Björk-Shiley tilting disc valves show the best hemodynamic results. This may be due to the most favourable ratio between internal and external diameter. Starr-Edwards prostheses with identical sizes show the most identical results if compared to each other. Therfore we suggest that Starr-Edwards prostheses open completely in every case. However, there is an important pressure gradient caused by the small internal diameter. Lillehei-Kaster pivoting disc valves reach surprisingly small functional valve areas. This may be caused by an incomplete opening of the disc.