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Published on: March 19, 2016
Platelet survival time following aortic valve replacement.
Circulation
|February 1, 1975
Summary
Aortic valve replacement with Starr-Edwards prostheses or stented homografts shortens platelet survival time, increasing thromboembolism risk. Direct homografts do not affect platelet survival, suggesting they are a safer alternative for preventing blood clots.
Area of Science:
- Cardiovascular Surgery
- Hematology
- Biomaterials Science
Background:
- Thromboembolism is a significant complication after aortic valve replacement (AVR).
- Previous studies linked shortened platelet survival time to thromboembolism in mitral valve patients.
- This study investigates platelet survival in patients undergoing AVR for aortic valve disease.
Purpose of the Study:
- To measure platelet survival time in patients with aortic valve disease before and after AVR.
- To compare platelet survival times across different prosthetic valves and homograft types.
- To determine the correlation between platelet survival time and thromboembolic events post-AVR.
Main Methods:
- Platelet survival time was measured using the chromium-51 method in 73 patients with aortic valve disease.
- Measurements were taken preoperatively and post-AVR with various prostheses (Starr-Edwards models) and aortic homografts (stented and direct).
- Platelet survival was analyzed in relation to thromboembolic history and platelet suppressant therapy.
Main Results:
- Preoperative platelet survival was normal (3.4 ± 0.14 days).
- Starr-Edwards prostheses and stented aortic homografts significantly shortened platelet survival (2.5–3.0 days, P < 0.001).
- Directly sewn aortic homografts maintained normal platelet survival (3.7 ± 0.24 days).
- Patients with Starr-Edwards prostheses and a history of thromboembolism had significantly shorter platelet survival (2.7 ± 0.12 days, P < 0.001).
- Platelet suppressant therapy improved platelet survival in patients with Starr-Edwards devices and thromboembolism.
Conclusions:
- Starr-Edwards valves and stented aortic homografts alter platelet survival, increasing thromboembolism risk.
- Directly sewn aortic homografts do not appear to affect platelet survival.
- Shortened platelet survival time is correlated with thromboembolic events following AVR, particularly with certain prosthetic devices.
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