P150. Biomechanical Assessment of No-cut Tricuspidization vs Bicuspidization Repairs in Quadricuspid Truncal Valve Model

Objective: To compare the impact of no-cut tricuspidization and bicuspidization repairs on valve performance in a diseased quadricuspid truncal valve model.

Methods: A Type C quadricuspid valve disease model (two symmetric dominant and two symmetric diminutive leaflets) was created in explanted porcine aortic roots. Three types of repairs-tricuspidization (sewing two diminutive leaflets together), symmetric bicuspidization (diminutive-dominant, diminutive-dominant), and asymmetric bicuspidization (diminutive-diminutive, dominant-dominant)-were completed without cutting or adding leaflet material. Each group was run on a validated ex-vivo univentricular system under physiological parameters for 40 cycles. All groups were tested within the same aortic root to minimize inter-root differences. Outcomes included transvalvular gradient, regurgitation fraction, and orifice area. Linear mixed effects model and pairwise comparisons were employed to compare outcomes across groups.

Results: Across three aortic roots of mean diameter 20.5 ± 1.5 cm, the diseased truncal valve had mean transvalvular gradient of 40.9 ± 7.3 mm Hg, regurgitation fraction of 50.4 ± 8.9%, and orifice area of 1.62 ± 0.11 cm² at 6.9 ± 0.1 L/min cardiac output. All repair groups had significantly improved regurgitation and transvalvular gradient compared to the diseased control (p<0.001). The tricuspidization repair demonstrated significantly lower transvalvular gradient (18.0±2.2 mm Hg, p<0.001) and regurgitation fraction (14.2±7.7%, p<0.001) compared to the bicuspidization techniques. While all repairs decreased valve orifice area (p<0.001), tricuspidization was associated with the least decrease in area (1.59 ± 0.12 cm², p < 0.001).

Conclusions: Repair of diseased Type C quadricuspid valve without cutting of leaflet material is feasible. Tricuspidization repair is associated with lower transvalvular gradient, reduced regurgitation fraction, and higher orifice area compared to bicuspidization techniques.

Perry Choi (1), Amit Sharir (1), Riya Nilkant (1), Alexander D. Kaiser (1), Michael Ma (1), (1) Stanford University, Stanford, CA

Perry Choi

Poster Presenter

Dr. Perry Choi is a 4th year resident in Stanford's Integrated Cardiothoracic Surgery Residency Program. He received his MD at Harvard Medical School, where he spent time conducting research on mitral valve replacement options in the pediatric population under the mentorship of Dr. Sitaram Emani at Boston Children's Hospital. Currently, he is working as a research fellow in the labs of Dr. Michael Ma and Dr. Joseph Woo, investigating the biomechanics of ventricular remodeling and complex valvular repair techniques in congenital heart disease. His career interests include academic surgery, adult congenital cardiac disease, and surgical education. 

Specialties: Congenital