Month: July 2026

Acta Biomater. 2026 Aug;219:224-235. doi: 10.1016/j.actbio.2026.06.040. Epub 2026 Jun 19.

ABSTRACT

Heterograft biomaterials, such as glutaraldehyde-pretreated bovine pericardium (BP), are used to fabricate bioprosthetic heart valves (BHV). BHV durability is limited by structural valve degeneration (SVD), which is caused by either advanced glycation end products (AGE) with associated serum protein deposition, calcification, or both. Vitamin B6 vitamers have been investigated experimentally and clinically for mitigating AGE formation that complicates diabetes. In the present study, we investigated a vitamin B6-based photo-responsive molecule, Pyriphenone (PPh), hypothesizing that PPh could mitigate both BP AGE-serum protein uptake and BP calcification in vivo. PPh was synthesized by reacting pyridoxamine with benzophenone. PPh was optimally soluble in ethanol, and PPh-ethanol solutions were used for all PPh studies. PPh was demonstrated to become covalently and stably attached to BP with exposure to ultraviolet light. PPh-BP demonstrated significantly reduced in vitro AGE deposition and associated serum albumin uptake, versus unmodified BP. PPh-BP showed significant resistance to oxidation in vitro and demonstrated comparable biaxial mechanical properties to unmodified BP. In vitro hydrodynamic testing of trileaflet BHV fabricated from BP-PPh demonstrated no alterations of functionality, compared to unmodified BHV. In vivo 28-day subdermal implants in juvenile rats with either PPh-BP or unmodified BP demonstrated that PPh significantly mitigated AGE and serum albumin uptake, and calcification versus unmodified BP. Ex vivo studies of BP-PPh exposed to human whole blood demonstrated significantly reduced adhesion of platelets and white blood cells versus unmodified BP. In conclusion, PPh-BP mitigates calcification, AGE, and serum albumin uptake and reduces platelet and white blood cell adhesion. STATEMENT OF SIGNIFICANCE: Heart valve disease is highly prevalent, affecting millions. At this time, it can only be treated by either surgical valve repair or replacement of the diseased valve with a prosthesis. Bioprosthetic heart valves, fabricated from heterograft materials, are the most widely used heart valve replacements. However, these devices have poor durability due to calcification and advanced glycation end-product (AGE) deposition, which cause structural valve degeneration. Pyriphenone, the subject of this paper, is a compound synthesized by the authors that is shown in this paper to confer resistance to bioprosthetic valve calcification and AGE deposition.

PMID:42315002 | PMC:PMC13352493 | DOI:10.1016/j.actbio.2026.06.040

Acta Biomater. 2026 Aug;219:224-235. doi: 10.1016/j.actbio.2026.06.040. Epub 2026 Jun 19.

ABSTRACT

Heterograft biomaterials, such as glutaraldehyde-pretreated bovine pericardium (BP), are used to fabricate bioprosthetic heart valves (BHV). BHV durability is limited by structural valve degeneration (SVD), which is caused by either advanced glycation end products (AGE) with associated serum protein deposition, calcification, or both. Vitamin B6 vitamers have been investigated experimentally and clinically for mitigating AGE formation that complicates diabetes. In the present study, we investigated a vitamin B6-based photo-responsive molecule, Pyriphenone (PPh), hypothesizing that PPh could mitigate both BP AGE-serum protein uptake and BP calcification in vivo. PPh was synthesized by reacting pyridoxamine with benzophenone. PPh was optimally soluble in ethanol, and PPh-ethanol solutions were used for all PPh studies. PPh was demonstrated to become covalently and stably attached to BP with exposure to ultraviolet light. PPh-BP demonstrated significantly reduced in vitro AGE deposition and associated serum albumin uptake, versus unmodified BP. PPh-BP showed significant resistance to oxidation in vitro and demonstrated comparable biaxial mechanical properties to unmodified BP. In vitro hydrodynamic testing of trileaflet BHV fabricated from BP-PPh demonstrated no alterations of functionality, compared to unmodified BHV. In vivo 28-day subdermal implants in juvenile rats with either PPh-BP or unmodified BP demonstrated that PPh significantly mitigated AGE and serum albumin uptake, and calcification versus unmodified BP. Ex vivo studies of BP-PPh exposed to human whole blood demonstrated significantly reduced adhesion of platelets and white blood cells versus unmodified BP. In conclusion, PPh-BP mitigates calcification, AGE, and serum albumin uptake and reduces platelet and white blood cell adhesion. STATEMENT OF SIGNIFICANCE: Heart valve disease is highly prevalent, affecting millions. At this time, it can only be treated by either surgical valve repair or replacement of the diseased valve with a prosthesis. Bioprosthetic heart valves, fabricated from heterograft materials, are the most widely used heart valve replacements. However, these devices have poor durability due to calcification and advanced glycation end-product (AGE) deposition, which cause structural valve degeneration. Pyriphenone, the subject of this paper, is a compound synthesized by the authors that is shown in this paper to confer resistance to bioprosthetic valve calcification and AGE deposition.

PMID:42315002 | PMC:PMC13352493 | DOI:10.1016/j.actbio.2026.06.040

Int J Surg Case Rep. 2026 Mar 26;138(6):2164-2167. doi: 10.1097/RC9.0000000000000366. eCollection 2026 Jun.

ABSTRACT

INTRODUCTION AND IMPORTANCE: Tuberculous aneurysm of the ascending aorta is extremely rare and life-threatening, particularly in elderly patients. Early recognition and appropriate surgical management are essential to prevent fatal rupture.

CASE PRESENTATION: An 84-year-old man presented with hemoptysis and chest tightness. Computed tomography revealed a saccular aneurysm of the ascending aorta with sternal erosion. During surgery, the aneurysm showed a caseous appearance with dense adhesions and infiltration into adjacent tissue. Frozen section demonstrated granulomatous inflammation suggesting tuberculous aortitis, which was later confirmed by postoperative Xpert MTB/RIF assay. A double-layer aortic repair was performed using an inner bovine pericardial patch and an outer Gelweave graft. The patient recovered well under antituberculous therapy and remained stable at 7-month follow-up.

CLINICAL DISCUSSION: Tuberculous aortitis in elderly patients is challenging due to degenerative aortic wall changes and hypertension. Intraoperative frozen section combined with gross findings played a key role in guiding the surgical strategy. The double-layer repair provided infection control and mechanical durability, consistent with current literature supporting biologic-synthetic hybrid reconstruction in infected aneurysms.

CONCLUSION: A tuberculous aneurysm of the ascending aorta should be considered in atypical cases presenting with hemoptysis. In elderly patients with degenerative aortic walls and hypertension, double-layer repair offers effective infection control and durability when combined with appropriate antituberculous therapy. Early diagnosis and tailored surgical planning are crucial for favorable outcomes.

PMID:42253673 | PMC:PMC13236237 | DOI:10.1097/RC9.0000000000000366

Ann Biomed Eng. 2026 Jun 9. doi: 10.1007/s10439-026-04207-5. Online ahead of print.

ABSTRACT

BACKGROUND: The biomechanical performance of bileaflet transcatheter mitral valves (TMVs) depends on complex interactions between leaflet material behavior and stent design. However, the contributions of leaflet materials and constitutive models, stent materials, and stent geometry to valve function and durability remain poorly understood.

METHODS: A parametric finite element study was conducted using a CAD model of a bileaflet TMV subjected to physiological pressure loading. Five leaflet material models were evaluated: 3 glutaraldehyde-fixed tissues-bovine pericardium (BP; FBP1, FBP2) and porcine pericardium (PP; FPP)-and 2 unfixed tissues-bovine (UBP) and porcine pericardium (UPP). BP was modeled as a linear elastic (FBP1) and Ogden (FBP2). Each was paired with 2 stent materials, cobalt chromium (CoCr) and nitinol, and 3 stent cell densities (low, medium, high), yielding 30 configurations. Von Mises stresses and relative leaflet opening were quantified.

RESULTS: UPP achieved the largest opening (30-32%) with the lowest leaflet 99th percentile stresses (0.048-0.050 MPa), while FBP1 produced the smallest opening (8-9%) and highest leaflet stresses (0.077-0.078 MPa). Leaflet 99th percentile stress was strongly inversely correlated with valve opening (Spearman r=-0.9, p<0.01). Stent material had a negligible effect on valve opening but affected stent stress notably, with nitinol exhibiting about 2-3 orders of magnitude lower stresses compared to CoCr. Increasing stent cell density improved stress distribution with only a modest reduction in opening.

CONCLUSION: Leaflet material model was the primary determinant of bileaflet TMV biomechanical performance, whereas stent material and cell density exerted secondary but meaningful effects. These findings offer insights that may guide the design of more optimized TMV replacement devices.

PMID:42262702 | DOI:10.1007/s10439-026-04207-5

Ann Biomed Eng. 2026 Jun 9. doi: 10.1007/s10439-026-04207-5. Online ahead of print.

ABSTRACT

BACKGROUND: The biomechanical performance of bileaflet transcatheter mitral valves (TMVs) depends on complex interactions between leaflet material behavior and stent design. However, the contributions of leaflet materials and constitutive models, stent materials, and stent geometry to valve function and durability remain poorly understood.

METHODS: A parametric finite element study was conducted using a CAD model of a bileaflet TMV subjected to physiological pressure loading. Five leaflet material models were evaluated: 3 glutaraldehyde-fixed tissues-bovine pericardium (BP; FBP1, FBP2) and porcine pericardium (PP; FPP)-and 2 unfixed tissues-bovine (UBP) and porcine pericardium (UPP). BP was modeled as a linear elastic (FBP1) and Ogden (FBP2). Each was paired with 2 stent materials, cobalt chromium (CoCr) and nitinol, and 3 stent cell densities (low, medium, high), yielding 30 configurations. Von Mises stresses and relative leaflet opening were quantified.

RESULTS: UPP achieved the largest opening (30-32%) with the lowest leaflet 99th percentile stresses (0.048-0.050 MPa), while FBP1 produced the smallest opening (8-9%) and highest leaflet stresses (0.077-0.078 MPa). Leaflet 99th percentile stress was strongly inversely correlated with valve opening (Spearman r=-0.9, p<0.01). Stent material had a negligible effect on valve opening but affected stent stress notably, with nitinol exhibiting about 2-3 orders of magnitude lower stresses compared to CoCr. Increasing stent cell density improved stress distribution with only a modest reduction in opening.

CONCLUSION: Leaflet material model was the primary determinant of bileaflet TMV biomechanical performance, whereas stent material and cell density exerted secondary but meaningful effects. These findings offer insights that may guide the design of more optimized TMV replacement devices.

PMID:42262702 | DOI:10.1007/s10439-026-04207-5

Ann Biomed Eng. 2026 Jun 9. doi: 10.1007/s10439-026-04207-5. Online ahead of print.

ABSTRACT

BACKGROUND: The biomechanical performance of bileaflet transcatheter mitral valves (TMVs) depends on complex interactions between leaflet material behavior and stent design. However, the contributions of leaflet materials and constitutive models, stent materials, and stent geometry to valve function and durability remain poorly understood.

METHODS: A parametric finite element study was conducted using a CAD model of a bileaflet TMV subjected to physiological pressure loading. Five leaflet material models were evaluated: 3 glutaraldehyde-fixed tissues-bovine pericardium (BP; FBP1, FBP2) and porcine pericardium (PP; FPP)-and 2 unfixed tissues-bovine (UBP) and porcine pericardium (UPP). BP was modeled as a linear elastic (FBP1) and Ogden (FBP2). Each was paired with 2 stent materials, cobalt chromium (CoCr) and nitinol, and 3 stent cell densities (low, medium, high), yielding 30 configurations. Von Mises stresses and relative leaflet opening were quantified.

RESULTS: UPP achieved the largest opening (30-32%) with the lowest leaflet 99th percentile stresses (0.048-0.050 MPa), while FBP1 produced the smallest opening (8-9%) and highest leaflet stresses (0.077-0.078 MPa). Leaflet 99th percentile stress was strongly inversely correlated with valve opening (Spearman r=-0.9, p<0.01). Stent material had a negligible effect on valve opening but affected stent stress notably, with nitinol exhibiting about 2-3 orders of magnitude lower stresses compared to CoCr. Increasing stent cell density improved stress distribution with only a modest reduction in opening.

CONCLUSION: Leaflet material model was the primary determinant of bileaflet TMV biomechanical performance, whereas stent material and cell density exerted secondary but meaningful effects. These findings offer insights that may guide the design of more optimized TMV replacement devices.

PMID:42262702 | DOI:10.1007/s10439-026-04207-5

Cureus. 2026 Apr 29;18(4):e107945. doi: 10.7759/cureus.107945. eCollection 2026 Apr.

ABSTRACT

Ventricular septal rupture (VSR) is a rare but catastrophic mechanical complication of acute myocardial infarction, even in the contemporary reperfusion era. Although early reperfusion strategies have significantly reduced its incidence, they do not completely eliminate the risk. We report the case of a 76-year-old man with a history of hypertension and no prior structural heart disease who presented with an anterior ST-elevation myocardial infarction (STEMI). He received tenecteplase 2 hours and 37 minutes after symptom onset and was subsequently referred for routine percutaneous coronary intervention (PCI), during which a stent was implanted in the left anterior descending (LAD) artery. During in-hospital monitoring, a new harsh holosystolic murmur was detected. Transthoracic echocardiography revealed an 11-mm interventricular septal defect with left-to-right shunting, which was confirmed by color and spectral Doppler. Despite this mechanical complication, the patient remained hemodynamically stable and did not require vasopressor support. He underwent successful surgical repair using an infarct exclusion technique with a bovine pericardial patch. The postoperative course was favorable, with no need for mechanical circulatory support, extubation within the first 12 hours, no requirement for high-dose vasoactive amines, and no residual shunt on follow-up echocardiography. He was discharged home with outpatient follow-up. This case highlights that post-infarction VSR may occur despite timely pharmaco-invasive reperfusion, particularly in anterior STEMI, and underscores the importance of continued clinical vigilance even after apparently successful reperfusion. Early recognition through physical examination and echocardiography, together with prompt multidisciplinary management, may allow for favorable outcomes in selected patients.

PMID:42220791 | PMC:PMC13220294 | DOI:10.7759/cureus.107945

Ann Biomed Eng. 2026 Jun 9. doi: 10.1007/s10439-026-04207-5. Online ahead of print.

ABSTRACT

BACKGROUND: The biomechanical performance of bileaflet transcatheter mitral valves (TMVs) depends on complex interactions between leaflet material behavior and stent design. However, the contributions of leaflet materials and constitutive models, stent materials, and stent geometry to valve function and durability remain poorly understood.

METHODS: A parametric finite element study was conducted using a CAD model of a bileaflet TMV subjected to physiological pressure loading. Five leaflet material models were evaluated: 3 glutaraldehyde-fixed tissues-bovine pericardium (BP; FBP1, FBP2) and porcine pericardium (PP; FPP)-and 2 unfixed tissues-bovine (UBP) and porcine pericardium (UPP). BP was modeled as a linear elastic (FBP1) and Ogden (FBP2). Each was paired with 2 stent materials, cobalt chromium (CoCr) and nitinol, and 3 stent cell densities (low, medium, high), yielding 30 configurations. Von Mises stresses and relative leaflet opening were quantified.

RESULTS: UPP achieved the largest opening (30-32%) with the lowest leaflet 99th percentile stresses (0.048-0.050 MPa), while FBP1 produced the smallest opening (8-9%) and highest leaflet stresses (0.077-0.078 MPa). Leaflet 99th percentile stress was strongly inversely correlated with valve opening (Spearman r=-0.9, p<0.01). Stent material had a negligible effect on valve opening but affected stent stress notably, with nitinol exhibiting about 2-3 orders of magnitude lower stresses compared to CoCr. Increasing stent cell density improved stress distribution with only a modest reduction in opening.

CONCLUSION: Leaflet material model was the primary determinant of bileaflet TMV biomechanical performance, whereas stent material and cell density exerted secondary but meaningful effects. These findings offer insights that may guide the design of more optimized TMV replacement devices.

PMID:42262702 | DOI:10.1007/s10439-026-04207-5

Ann Biomed Eng. 2026 Jun 9. doi: 10.1007/s10439-026-04207-5. Online ahead of print.

ABSTRACT

BACKGROUND: The biomechanical performance of bileaflet transcatheter mitral valves (TMVs) depends on complex interactions between leaflet material behavior and stent design. However, the contributions of leaflet materials and constitutive models, stent materials, and stent geometry to valve function and durability remain poorly understood.

METHODS: A parametric finite element study was conducted using a CAD model of a bileaflet TMV subjected to physiological pressure loading. Five leaflet material models were evaluated: 3 glutaraldehyde-fixed tissues-bovine pericardium (BP; FBP1, FBP2) and porcine pericardium (PP; FPP)-and 2 unfixed tissues-bovine (UBP) and porcine pericardium (UPP). BP was modeled as a linear elastic (FBP1) and Ogden (FBP2). Each was paired with 2 stent materials, cobalt chromium (CoCr) and nitinol, and 3 stent cell densities (low, medium, high), yielding 30 configurations. Von Mises stresses and relative leaflet opening were quantified.

RESULTS: UPP achieved the largest opening (30-32%) with the lowest leaflet 99th percentile stresses (0.048-0.050 MPa), while FBP1 produced the smallest opening (8-9%) and highest leaflet stresses (0.077-0.078 MPa). Leaflet 99th percentile stress was strongly inversely correlated with valve opening (Spearman r=-0.9, p<0.01). Stent material had a negligible effect on valve opening but affected stent stress notably, with nitinol exhibiting about 2-3 orders of magnitude lower stresses compared to CoCr. Increasing stent cell density improved stress distribution with only a modest reduction in opening.

CONCLUSION: Leaflet material model was the primary determinant of bileaflet TMV biomechanical performance, whereas stent material and cell density exerted secondary but meaningful effects. These findings offer insights that may guide the design of more optimized TMV replacement devices.

PMID:42262702 | DOI:10.1007/s10439-026-04207-5

Oper Neurosurg. 2026 Jun 3. doi: 10.1227/ons.0000000000002083. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVES: Circumferential defects of the dural sleeve of exiting lumbar nerve roots may occur after incidental durotomy, trauma, or deliberate opening of the root cuff during resection of nerve sheath tumors. Standard onlay duraplasty can control cerebrospinal fluid (CSF) leakage but does not restore the tubular dural-epineural conduit. We describe a collagen-matrix cuff technique for root sleeve reconstruction and report our initial institutional experience.

METHODS: This single-center, retrospective case series includes 9 consecutive reconstructions performed between January 2022 and October 2025 for intraoperatively recognized circumferential defects of exiting lumbar nerve root sleeves not amenable to safe primary suturing. The cohort comprised 6 iatrogenic root sleeve defects occurring during elective lumbar procedures (including instrumented and noninstrumented decompressive and/or stabilizing surgeries), 2 post-traumatic cases, and 1 elective tumor case presented as the illustrative case (L3 nerve root ganglioneuroma resection). Clinical records, intraoperative notes, and imaging were reviewed retrospectively. Minimum clinical and MRI follow-up was 6 months for all patients. Adjunctive lumbar drainage was used in one iatrogenic case.

RESULTS: In all cases, a bovine pericardium-derived collagen matrix was prehydrated, tailored, positioned under the root, sutured proximally to the dural margin at the root axilla, and wrapped to form a tubular cuff bridging the dural sac to the epineural segment, with distal reinforcement using fat and fibrin sealant. No patient required reoperation for CSF leak or pseudomeningocele. There were no cases of symptomatic nerve root herniation or new permanent neurological deficit. Radicular symptoms were stable or improved at the last follow-up.

CONCLUSION: Collagen-matrix cuff reconstruction is a simple, anatomically oriented option for circumferential lumbar root sleeve defects when primary closure is not feasible. In this initial single-center experience, the technique provided stable reconstruction without CSF-related complications and may represent a useful adjunct in selected complex root sleeve injuries.

PMID:42233683 | DOI:10.1227/ons.0000000000002083