Case report: Right atrium-inferior vena cava bypass in a patient with unusual cardiac cystic echinococcosis.

Cardiovascular hydatid disease is caused by parasitic infection of Echinococcus granulosus, which could be asymptomatic or life-threatening depending on lesion site, granuloma size, and disease progression. Diagnosis and treatment of cardiac echinococcosis should be under comprehensive consideration. In this case, we reported a successful right atrium-inferior vena cava bypass surgery in a 31-year-old female with unresectable right atrial echinococcosis and inferior vena cava obstruction.

Transcatheter Mitral Valve-in-Valve Implantations Using Inverted J-Valve.

Background: As bioprosthetic valves are being widely used, the incidence of structural valve deterioration increases, as well as the need for reoperation. Transcatheter mitral valve-in-valve implantations are being increasingly adopted as an alternative to redo-surgical mitral replacement for patients with high surgical risks. This study reports a series of transcatheter mitral valve-in-valve implantations using inverted J-valves. Methods: From April 2019 to September 2021, 17 symptomatic high-risk patients with mitral bioprosthetic valve dysfunction underwent transapical transcatheter mitral valve-in-valve implantations using inverted J-valves at our institution. Results: The median age was 70 years, with 76.5% being female. The median Society of Thoracic Surgeons predicted risk of mortality (STS PROM) was 17.2% (8.7-82.24%). All patients had successful transapical transcatheter mitral valve-in-valve implantations except for one intraoperative death due to left ventricle rupture. Four patients underwent simultaneous transcatheter aortic valve implantation, two of which had valve-in-valve transcatheter aortic valve implantation. There was no major complication except one case of bleeding. Thirty-day mortality was 11.8% (2/17), and 90-days mortality was 23.5% (4/17). Percentages of patients with New York Heart Association class III/IV symptoms decreased from 100 (17/17) to 20% (3/15) at 30-days. Median mitral inflow velocity was 1.95 mm/s at 30 days, compared to 2.7 mm/s at baseline. Median mitral valve effective orifice area increases from 1.5 mm at baseline to 1.85 mm at 30 days. Conclusion: Transcatheter transapical valve-in-valve implantations with J-valve can be a plausible solution to failed mitral bioprosthesis with acceptable results for high-risk patients.

Hyaluronic Acid-Grafted Bioprosthetic Heart Valves Achieved by Copolymerization Exhibited Improved Anticalcification and Antithrombogenicity.

Bioprosthetic heart valves (BHVs) are widely used in clinic, but they still have problems of calcification, thrombogenicity, and cytotoxicity. The reported techniques based on glutaraldehyde (Glut) crosslinking have difficulty in solving these problems simultaneously. In this study, we grafted Glut-crosslinked porcine pericardium (GA) with hyaluronic acid (HA) by radical copolymerization to improve its anticalcification and antithrombotic properties. Partially methacrylated poly-ε-lysine was used to introduce methacryl groups into GA. Then, HA-grafted porcine pericardium (GA-HA) was obtained by radical copolymerization. Rat's subcutaneous implantation results showed that the calcium content of GA-HA was significantly lower than that of GA (37 ± 29 µg/mg vs 188 ± 7 µg/mg), and the platelets adhering to the surface of GA-HA decreased by approximately 41% compared with GA. In conclusion, grafting porcine pericardium with HA by copolymerization might be feasible to improve the anticalcification and antithrombotic properties of BHVs.

A hydrophobic antifouling surface coating on bioprosthetic heart valves for enhanced antithrombogenicity.

Thrombosis is an important factor that causes the failure of artificial biological valves in addition to calcification and immune rejection. A hydrophobic antifouling surface can improve blood compatibility by reducing the absorption of protein. In this study, porcine pericardium was cross-linked with glycidyl methacrylate, and carbon-carbon double bonds were introduced. Then, fluoride monomer was added so that the pericardial surface would become hydrophobic and antifouling. Fluoride modification changed the hydrophilicity of the pericardium surface, and the surface water contact angle increased from 84° to 143°. Compared with unmodified pericardium, the adsorption of bovine serum albumin and fibrinogen decreased by 93.1% and 85%, respectively, and the anti-thrombogenicity was greatly enhanced.

Glycidyl methacrylate-crosslinked fish swim bladder as a novel cardiovascular biomaterial with improved antithrombotic and anticalcification properties.

At present, commercial artificial biological valves are mostly prepared by crosslinking bovine or porcine pericardia with glutaraldehyde. Swim bladder has similar components and lower immunogenicity compared to bovine or porcine pericardium. In this study, we used a glycidyl methacrylate (GMA)-based radical polymerization method to crosslink decellularized swim bladders. Amino and carboxyl groups in the swim bladder were reacted with epoxy groups on GMA to introduce carbon-carbon double bonds to the swim bladder. The results showed that the platelet adhesion of GMA-crosslinked swim bladders (GMA-SBs) decreased by 35%, as compared to that of glutaraldehyde-crosslinked swim bladders (GLUT-SBs). Moreover, the superior anticoagulant property was further verified by the ex vivo arteriovenous shunt assay. Meanwhile, the subcutaneous implantation in rats showed that GMA-SBs were able to effectively inhibit the calcification compared with GLUT-SBs. In conclusion, GMA-SBs showed improved antithrombotic and anticalcification properties compared to GLUT-SBs.

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.

A method for simultaneously crosslinking and functionalizing extracellular matrix-based biomaterials as bioprosthetic heart valves with enhanced endothelialization and reduced inflammation.

With the coming of an aging society and the emergence of transcatheter valve technology, the implantation of bioprosthetic heart valves (BHVs) in patients with valvular disease has significantly increased worldwide. Currently, most clinically available BHVs are crosslinked with glutaraldehyde (GLUT). However, the GLUT treated BHV is less durable due to the combined effect of multiple factors such as cytotoxicity, immune responses, and calcification. In this study, the in-situ polymerization of sulfonic monomers with a decellularized extracellular matrix (ECM) was performed to simultaneously achieve the crosslinking and functionalization of ECM. Subsequently, the feasibility of the hybrid ECM used as leaflet material of BHV was evaluated. In in-vitro tests, the results indicated that the hybrid ECM fixed collagen efficiently and the introduction of sulfonic polymer promoted the proliferation and migration of human umbilical vein endothelial cells (HUVECs). In in-vivo tests, after being implanted in SD rats and mice, the hybrid ECM significantly inhibited immune response and calcification compared with the non-hybrid counterpart and GLUT crosslinked tissue. These results indicated that the hybrid ECM exhibited more competitive stability and better biocompatibility compared to these features in GLUT-crosslinked valve. Therefore, the sulfonic polymer hybrid ECM provides a potential material for more durable BHV and the in-situ polymerization strategy can serve as a general treatment method for tissue crosslinking as well as tailoring the biophysical properties of ECM.

Extracellular matrix coating improves the biocompatibility of polymeric heart valves.

Prosthetic heart valve replacement is an effective therapy for patients with valvular heart disease. New-type polymer materials provide potential choices of material for preparing prosthetic heart valves. In this study, we focused on enhancing the biocompatibility of polystyrene-block-isobutylene-block-styrene (SIBS) by surface modification with an extracellular matrix (ECM). Experimental results demonstrated that the ECM coating increased the adsorption resistance against protein and platelets. SIBS coated with an ECM adsorbed much less bovine serum albumin and fibrinogen (5.38 µg cm-2 and 31.53 µg cm-2, respectively) than the original material (90.84 µg cm-2 and 132.38 µg cm-2, respectively). The relative platelet adsorption of the ECM-modified SIBS was lower than that of SIBS (0.04 versus 0.10). Moreover, the surface coating could also reduce endothelial cytotoxicity, suppress the immune response, and potentially induce tissue regeneration. In conclusion, ECM coating improved the biocompatibility of SIBS effectively.