Pulse duplicator study of the right ventricular outflow tract: changes induced by surgery

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Cardiac Anatomy

Background:

• Right ventricular outflow tract (RVOT) reconstruction is crucial in congenital heart defect repair.
• Transannular and composite monocusp patches are common surgical techniques.
• Understanding patch-induced leaflet dynamics is vital for optimizing outcomes.

Purpose of the Study:

• To evaluate the hemodynamic effects of RVOT reconstruction using different patch types.
• To assess the functional impact of transannular and composite monocusp patches on pulmonary valve function.
• To analyze leaflet motion and distortion post-RVOT reconstruction.

Main Methods:

• Utilized a pulse duplicator system with 31 adult pig hearts.
• Compared normal hearts (n=6) with those receiving transannular patches (n=7) and composite monocusp patches (n=18).
• Observed and analyzed leaflet movement and valve competency under simulated physiological conditions.

Main Results:

• Insertion of RVOT patches induced abnormal movements and distortion of posterior pulmonary leaflets.
• The composite monocusp patch resulted in a competent pulmonary valve.
• Despite competency, the bovine pericardial cusp in the monocusp patch exhibited slower movements, leading to mild regurgitation.

Conclusions:

• RVOT reconstruction with patches can negatively affect pulmonary leaflet dynamics.
• Composite monocusp patches offer a solution for pulmonary valve competency post-RVOT reconstruction.
• Further refinement of patch materials and design may mitigate residual regurgitation.