Analysis of Bioprosthetic Aortic Valve Thrombosis—Implications and Management Strategies

Valve Thrombosis Following Transcatheter Aortic Valve Replacement: State-of-the-Art Review

Transcatheter aortic valve replacement (TAVR) is a well-established treatment for severe aortic stenosis, especially in patients over 75 or those at high surgical risk. While these prosthetic valves have a lower thrombogenic profile than mechanical heart valves, leaflet thrombosis in transcatheter aortic valves (TAV) occurs in an estimated 5%-40% of cases. Most TAV thromboses are subclinical and can be detected via cardiac computed tomography (CCT), which reveals hypo-attenuating leaflet thickening and reduced leaflet motion in asymptomatic patients without elevated transprosthetic gradients on echocardiography. The mechanisms behind TAV thrombosis involve local mechanical triggers, patient predisposing factors, and device and procedure-related aspects. The ideal antithrombotic therapy post-TAVR depends on individual patient characteristics, balancing bleeding risks with the need for oral anticoagulants. Data on the optimal management of TAV thrombosis and the routine use of CT post-TAVR are limited. While anticoagulation effectively resolves clinically significant prosthesis thrombosis, its benefit in subclinical cases is unclear. There is an ongoing debate about whether subclinical leaflet thrombosis precedes clinical valve thrombosis, making the ideal follow-up after valve implantation uncertain. This article aims to provide a comprehensive review, summarizing current data on the incidence of TAVR thrombosis, underlying mechanisms, clinical and imaging diagnosis, management strategies, preventive measures, and long-term follow-up.

A Propensity-Matched National Analysis of Transcatheter Aortic Valve Implantation Outcome in Patients With Gastrointestinal Bleeding

Gastrointestinal (GI) bleeding is often observed in severe aortic stenosis, which can be attributed to the presence of arteriovenous malformations and von Willebrand's factor deficiency. GI is one of the most common complications in patients who underwent transcatheter aortic valve implantation (TAVI). The outcome of the TAVI procedure with GI bleeding is unknown. We performed an International Classification of Diseases, Tenth Revision-based national cohort analysis using the national readmission database from 2016 to 2020. We compared cardiovascular outcomes, mortality, and readmission rates of patients with TAVI who developed GI bleeding compared with those who had no GI bleeding. A total of 320,353 hospitalizations with TAVI were identified from the year 2016 to 2020. Patients with TAVI with GI bleeding were 6,193.37 and without GI bleeding were 314,160. The median age of the patients with TAVI with GI or without GI bleeding was 80. GI bleed patients had statistically significantly higher readmission rates at 30, 90, and 180 days and they had higher odds of in-hospital mortality (adjusted odds ratio [aOR] = 6.35; 95% confidence interval [CI]: 5.37 to 7.52; p <0.0001), acute kidney injury (aOR = 5.22; 95% CI:4.75 to 5.74; p <0.0001), stroke (aOR = 2.83; 95% CI 2.05 to 3.91 p:0.0001, postprocedural bleeding (aOR: 1.76; 95% CI: 1.35 to 2.30; p:0.0001), cardiac tamponade (aOR = 2.54; 95% CI 1.86 to 3.49; p <0.0001), use of mechanical circulatory support (aOR: 5.33; 95% CI:4.13 to 6.86; p <0.0001), and heart failure (aOR:1.73; 95%CI: 1.54 to 1.94; p <0.0001). The total cost of hospitalization and length of stay was higher in the GI bleed group. Patients with TAVI with GI bleeding have worse clinical outcomes and higher in-hospital mortality and readmission rates compared with patients with no GI bleeding.

Valve-in-valve transcatheter aortic valve replacement versus redo aortic valve replacement: which procedure for which patient?

INTRODUCTION

Bioprosthetic aortic valves are increasingly being utilized in a younger population due to improved durability and possibility for future valve-in-valve replacement. This has resulted in a larger population of patients with bioprosthetic aortic valve degeneration requiring re-intervention. Despite no head-to-head comparisons between redo surgical aortic valve replacement (SAVR) and valve-in-valve transcatheter aortic valve replacement (ViV TAVR), observational studies suggest a comparable long-term risk between which led to the incorporation of ViV TAVR to current guidelines.

AREAS COVERED

This article summarizes the comparative performance of redo SAVR versus ViV TAVR in patients with bioprosthetic valve dysfunction and provides a guide to better understand which procedure is best for which patient.

EXPERT OPINION

With the rising use of TAVR, we will be confronted with more bioprosthetic aortic valve degeneration requiring re-intervention. Based on the available evidence and expert consensus, we propose that patients with bioprosthetic aortic valve degeneration be treated with ViV TAVR if they have a history of radiation heart disease, prohibitive surgical risk, and multiple sternotomies; while patients with small prostheses, history of infective endocarditis, those at high risk for coronary obstruction, and those with need for other cardiac surgery will be managed with redo SAVR.

Cross-Linking Porcine Pericardium by 3,4-Dihydroxybenzaldehyde: A Novel Method to Improve the Biocompatibility of Bioprosthetic Valve

Heart valve replacement is an effective therapy for patients with moderate to severe valvular stenosis or regurgitation. Most bioprosthetic heart valves applied clinically are based on cross-linking with glutaraldehyde (GLUT), but they have some drawbacks like high cytotoxicity, severe calcification, and poor hemocompatibility. In this study, we focused on enhancing the properties of bioprosthetic heart valves by cross-linking with 3,4-dihydroxybenzaldehyde (DHBA). The experiment results revealed that compared with GLUT cross-linked porcine pericardium (PP), the relative amount of platelets absorbed on the surface of DHBA cross-linked PP decreased from 0.294 ± 0.034 to 0.176 ± 0.028, and the activated partial thromboplastin time (APTT) increased from 9.9 ± 0.1 to 15.2 ± 0.1 s, indicating improved hemocompatibility. Moreover, anticalcification performance and cytocompatibility were greatly enhanced by DHBA cross-linking. In conclusion, the properties of bioprosthetic valves could be effectively improved by processing valves with a DHBA-based cross-linking method.