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Published on: June 8, 2022
A novel technique in a sheep model for evaluating prosthetic heart valve performance
1Department of Surgery, Cooper Hospital/University Medical Center, University of Medicine, Camden, New Jersey, USA.
Summary
A new sheep model allows testing mechanical heart valve thrombogenicity without cardiac bypass. This method revealed clot formation at valve hinges, impacting leaflet movement in prosthetic heart valves.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Surgical Innovation
Background:
- Evaluating prosthetic heart valve thrombogenicity is crucial for patient safety.
- Existing animal models often require cardiopulmonary bypass or carry risks like paraplegia.
- A need exists for a more accessible and safer animal model.
Purpose of the Study:
- To develop and validate a novel sheep model for assessing mechanical heart valve thrombogenicity.
- To enable evaluation without cardiopulmonary bypass or significant surgical risks.
- To investigate clot formation in mechanical heart valves placed in the systemic circulation.
Main Methods:
- A left lateral thoracotomy was performed in six sheep.
- A mechanical heart valve within a valved conduit was anastomosed to the descending thoracic aorta.
- Partial aortic occlusion was used, avoiding complete thoracic aortic clamping and cardiopulmonary bypass.
Main Results:
- The novel surgical technique was successfully implemented with a median operative time of 170 minutes and estimated blood loss of 250 cc.
- No instances of paraplegia were observed postoperatively.
- All evaluated mechanical heart valves showed clot formation at the hinges, impeding leaflet motion, despite maintaining patency and valve function.
Conclusions:
- This innovative sheep model effectively evaluates prosthetic heart valve thrombogenicity in the systemic circulation.
- The model avoids the need for cardiac bypass and mitigates the risk of paraplegia.
- Findings indicate significant clot formation at the hinges of mechanical heart valves, impacting their function.
