The aim of this study was to determine whether second-generation porcine bioprostheses, glutaraldehyde fixed at pressures said to be less than 4 mm Hg, exhibit more natural leaflet material properties than earlier valves fixed at 80 to 100 mm Hg. Biaxial mechanical testing techniques were used to compare Carpentier-Edwards SAV, St. Jude Medical BioImplant, Hancock II, and Medtronic Intact bioprostheses (12 leaflets from four valves in each case) with fresh porcine aortic valves and high pressure-fixed Carpentier-Edwards 6625 bioprostheses (14 leaflets from five valves in each case). The circumferential extensibility of leaflets from Medtronic Intact bioprostheses and from fresh porcine aortic valves were not significantly different (p greater than 0.05), whereas leaflets from the other second-generation valves tested and from Carpentier-Edwards 6625 valves were highly inextensible in the circumferential direction. The radial material properties of leaflets from all bioprostheses differed from those of fresh porcine aortic valves, which were very extensible with a high pretransitional compliance. The radial extensibility and compliance of Hancock II, St. Jude Medical BioImplant, and Carpentier-Edwards 6625 leaflets were not significantly different (p greater than 0.05). In the radial direction, Carpentier-Edwards SAV and Medtronic Intact valve leaflets were substantially more extensible than Carpentier-Edwards 6625 leaflets (p less than 0.01), whereas Medtronic Intact leaflets were more compliant than all other bioprostheses. These data demonstrate (1) that second-generation porcine bioprosthetic valves do not necessarily exhibit more natural leaflet material properties than earlier high pressure-fixed xenografts and (2) that Medtronic Intact valve leaflets have material properties most closely approximating the fresh porcine aortic valve.
Download full-text PDF |
Source |
|---|
Publication Analysis
Top Keywords
Similar Publications
Extended Rhythm Monitoring to Assess for Ventricular Arrhythmias After Transcatheter Pulmonary Valve Replacement With the Harmony Valve.
Circ Cardiovasc Interv
January 2025
Department of Pediatrics, Pediatric Cardiology (J.K.Y., L.W., A.C.T., H.C., A.W.R., L.F.P., S.R.C., A.M.D., D.B.M.), Stanford University, Palo Alto, CA.
Background: Varying rates of nonsustained ventricular tachycardia (NSVT) have been reported early after transcatheter pulmonary valve replacement (TPVR) with the Harmony valve, but data regarding rhythm outcomes beyond hospital discharge are limited. This study aims to characterize ventricular arrhythmias after Harmony TPVR from implant through mid-term follow-up.
Methods: Ventricular arrhythmia data from postimplant telemetry and follow-up extended rhythm monitoring (ERM) were analyzed after Harmony TPVR.
Background: The EXCELLENT registry aimed to evaluate the effectiveness of the EMBOTRAP Revascularization Device in an all-comer population in a real-world setting, with a focus on the composition of retrieved clots.
Methods: EXCELLENT is a prospective, global registry of patients with acute ischemic stroke treated with EMBOTRAP as the first-line mechanical thrombectomy device conducted at 34 sites (25 sites contributing clot) from September 2018 to March 2021, utilizing core imaging and central histology laboratories blinded to clinical data, independent 90-day modified Rankin Scale assessment and Clinical Events Committee.
Results: After screening 3799 patients, a total of 997 subjects (mean age, 70.
Oral Muvalaplin for Lowering of Lipoprotein(a): A Randomized Clinical Trial.
JAMA
January 2025
Eli Lilly and Company, Indianapolis, Indiana.
Article Synopsis
- A recent study showed that muvalaplin effectively inhibits the formation of lipoprotein(a), reducing its levels significantly, with reductions up to 85.8% observed in higher dosages over a 12-week period for those at high cardiovascular risk.
- * The phase 2 trial involved 233 participants with elevated lipoprotein(a) and conditions like atherosclerosis and diabetes, testing different dosages of muvalaplin against a placebo.
- * Results indicated substantial decreases in lipoprotein(a) concentrations and generally demonstrated that muvalaplin is well tolerated, but the long-term effects on high-risk populations require further investigation.
Electrophysiologic characteristics and clinical correlation of right ventricular activation during left bundle branch area pacing (RV-LBBAP study).
Heart Rhythm
October 2024
Geisinger Heart Institute, Geisinger Commonwealth School of Medicine, Wilkes Barre, Pennsylvania.
Background: Left bundle branch area pacing (LBBAP) results in a right bundle branch (RBB) delay pattern because of preexcitation of the left bundle. The mechanism of right ventricular (RV) activation during LBBAP is largely unknown.
Objective: The aim of the study was to analyze the electrophysiologic characteristics of RV activation by mapping the RBB during LBBAP and its clinical correlation.
Comparison of a Novel Posterior Integrated Transfixation Sacroiliac Joint Fusion Approach to the Posterolateral and Lateral Approaches: A Cadaveric Biomechanical and Computational Analysis of the Fixation, Invasiveness, and Fusion Area.
Med Devices (Auckl)
October 2024
Medical Device Development, San Francisco, CA, USA.
Purpose: To concurrently assess and compare the fixation efficacy, invasiveness, and fusion potential of a posterior integrated transfixation cage system to the posterolateral threaded implant and lateral triangular rod systems, in a cadaveric model.
Methods And Materials: Twelve (12) cadaveric sacroiliac joint specimens were utilized and tested within the single-leg stance multidirectional pure moment bending model. Each specimen was tested in the intact, destabilized, treated (using posterior, posterolateral, and lateral systems), and post-fatigue conditions by applying 0 to ± 7.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!