Prosthetic Aortic Valve Fixation Study: 48 Replacement Valves Analyzed Using Digital Pressure Mapping

Abstract

<jats:sec><jats:title>Objective</jats:title><jats:p> Prostheses attachment is critical in aortic valve replacement surgery, yet reliable prosthetic security remains a challenge. Accurate techniques to analyze prosthetic fixation pressures may enable the use of fewer sutures while reducing the risk of paravalvular leaks (PVL). </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> Customized digital thin film pressure transducers were sutured between aortic annulus models and 21-mm bioprosthetic valves with 15 × 4-mm, 12 × 4-mm, or 9 × 6-mm-wide pledgeted mattress sutures. Simulating open and minimally invasive access, 4 surgeons, blinded to data acquisition, each secured 12 valves using manual knot-tying (hand-tied [HT] or knot-pusher [KP]) or automated titanium fasteners (TFs). Real-time pressure measurements and times were recorded. Two-dimensional (2D) and 3D pressure maps were generated for all valves. Pressures less than 80 mm Hg were considered at risk for PVL. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> Pressures under each knot (intrasuture) fell less than 80 mm Hg for 12 of 144 manual knots (5/144 HT, 7/144 KP) versus 0 of 288 TF (P &lt; 0.001). Pressures outside adjacent sutures (extrasuture) were less than 80 mm Hg in 10 of 60 HT, zero of 60 KP, and zero of 120 TF sites for 15 × 4-mm valves; 17 of 48 HT, 25 of 48 KP, and 12 of 96 TF for 12 × 4-mm valves; and 15 of 36 HT, 17 of 36 KP and 9 and 72 TF for 9 × 6-mm valves; P &lt; 0.001 all manual versus TF. Annular areas with pressures less than 80 mm Hg ranged from 0% of the sewing-ring area (all open TF) to 31% (12 × 4 mm, KP). The average time per manual knot, 46 seconds (HT, 31 seconds; KP, 61 seconds), was greater than TF, 14 seconds (P &lt; 0.005). </jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p> Reduced operative times and PVL risk would fortify the advantages of surgical aortic valve replacement. This research encourages continued exploration of technical factors in optimizing prosthetic valve security. </jats:p></jats:sec>

Comparison of Automated Titanium Fasteners to Hand-Tied Knots in Open Aortic Valve Replacement

“…17 This study further indicated that the prosthetic sewing cuff attachment pressures in the areas contained within the individual sutures (intrasuture) averaged double that of pressures obtained within the suture area of HT knots or knots secured using a knot pusher. 17 The adjacent attachment pressures in the areas outside of the individual suture (extrasuture) were also higher with the COR-KNOT secured prosthesis compared with those secured with HT knots. 17 Greater intrasuture and extrasuture pressure around the valve annulus complex could theoretically decrease the risk for PVL.…”

“…17 The adjacent attachment pressures in the areas outside of the individual suture (extrasuture) were also higher with the COR-KNOT secured prosthesis compared with those secured with HT knots. 17 Greater intrasuture and extrasuture pressure around the valve annulus complex could theoretically decrease the risk for PVL.…”

“…[14][15][16] Not only are TF faster than HT knots, but also the TF provide reproducible strength of suture securement. 8,17 Lee et al 17 showed that the COR-KNOT device generated more consistent pressure between the valve sewing cuff and underlying tissue, resulting in better seating of the valve prosthesis in an in vitro aortic root model. 17 This study further indicated that the prosthetic sewing cuff attachment pressures in the areas contained within the individual sutures (intrasuture) averaged double that of pressures obtained within the suture area of HT knots or knots secured using a knot pusher.…”

“…8,17 Lee et al 17 showed that the COR-KNOT device generated more consistent pressure between the valve sewing cuff and underlying tissue, resulting in better seating of the valve prosthesis in an in vitro aortic root model. 17 This study further indicated that the prosthetic sewing cuff attachment pressures in the areas contained within the individual sutures (intrasuture) averaged double that of pressures obtained within the suture area of HT knots or knots secured using a knot pusher. 17 The adjacent attachment pressures in the areas outside of the individual suture (extrasuture) were also higher with the COR-KNOT secured prosthesis compared with those secured with HT knots.…”

The role of Cor‐Knot in the future of cardiac surgery: A systematic review

“…This is likely due to decreased variability in attachment pressures resulting from its facilitation of tight approximation between the soft tissue of the annulus and prosthetic material (i.e. improved valve seating) 13,14 . The pressures under each knot and outside adjacent sutures were also higher than those of hand‐tied knots and those created using an endoscopic knot pusher 13 .…”