A computational framework for post‐TAVR cardiac conduction abnormality (CCA) risk assessment in patient‐specific anatomy

Abstract

Background Cardiac conduction abnormality (CCA)‐ one of the major persistent complications associated with transcatheter aortic valve replacement (TAVR) may lead to permanent pacemaker implantation. Localized stresses exerted by the device frame on the membranous septum (MS) which lies between the aortic annulus and the bundle of His, may disturb the cardiac conduction and cause the resultant CCA. We hypothesize that the area‐weighted average maximum principal logarithmic strain (AMPLS) in the MS region can predict the risk of CCA following TAVR. Methods Rigorous finite element‐based analysis was conducted in two patients (Balloon expandable TAVR recipients) to assess post‐TAVR CCA risk. Following the procedure one of the patients required permanent pacemaker (PPM) implantation while the other did not (control case). Patient‐specific aortic root was modeled, MS was identified from the CT image, and the TAVR deployment was simulated. Mechanical factors in the MS region such as logarithmic strain, contact force, contact pressure, contact pressure index (CPI) and their time history during the TAVR deployment; and anatomical factors such as MS length, implantation depth, were analyzed. Results Maximum AMPLS (0.47 and 0.37, respectively), contact force (0.92 N and 0.72 N, respectively), and CPI (3.99 and 2.86, respectively) in the MS region were significantly elevated in the PPM patient as compared to control patient. Conclusion Elevated stresses generated by TAVR devices during deployment appear to correlate with CCA risk, with AMPLS in the MS region emerging as a strong predictor that could be used for preprocedural planning in order to minimize CCA risk.

Effect of Sinotubular Junction Size on TAVR Leaflet Thrombosis: A Fluid-structure Interaction Analysis

“…The anonymized patient’s CT scan was acquired at Stony Brook University Hospital under the approval of the local institutional review board. The patient model, shown in Figure 2 a, was reconstructed following the procedures described in our previous study [39]. Briefly, the pre-TAVR CT scan of the selected patient was imported as DICOM file and segmented into 3D surface meshes using ITK-SNAP 3.6 [40].…”

Assessing Post-TAVR Cardiac Conduction Abnormalities Risk Using a Digital Twin of a Beating Heart

“…Therefore, additional patient-specific computational modeling may provide more accurate predictions of patient specific CCA risk. Recently, computational studies on patient-specific structural models have indicated that elevated contact pressure and contact pressure index (CPI) on the His bundle region in the intraventricular septum below the triangular space between the RCL and NCL for self-expandable TAVR cases (Rocatello et al 2018) and high area-weighted average logarithmic strain (AMPLS) and Contact force for balloon expandable TAVR cases were associated with onset of CCA following TAVR procedure (Reza et al 2022). To gain more insight into the mechanisms underlying post-TAVR CCA development and provide a more accurate assessment of CCA risk, it is essential to analyze the interaction between the TAVR prosthesis and conduction fibers within a realistic, electromechanically coupled, beating heart condition.…”