Author:

J Cardiothorac Surg. 2026 Jun 15. doi: 10.1186/s13019-026-04338-9. Online ahead of print.

ABSTRACT

BACKGROUND: Prosthetic valve endocarditis (PVE) after transcatheter aortic valve replacement (TAVR) is an uncommon but life-threatening complication associated with high embolic risk.

CASE PRESENTATION: A 82-year-old woman with prior TAVR presented with fever and malaise and was diagnosed with PVE due to Streptococcus Mutans. Transesophageal echocardiography revealed a large, highly mobile vegetation attached to the transcatheter valve, floating in the systolic jet of blood flow. Computed tomography demonstrated progressive splenic infarction and embolic involvement of the kidneys and mesenteric circulation, while no cerebral embolization occurred. At surgery, the previously visualized vegetation was no longer present, suggesting interval embolization. The transcatheter valve was explanted using cardiopulmonary bypass and cardioplegia. Radical debridement and annular enlargement with bovine pericardium were performed, followed by implantation of a surgical bioprosthesis using infection-conscious techniques. The patient recovered uneventfully. Post hoc analysis may suggest that proximal origin of the supra-aortic vessels (type III aortic arch configuration with the innominate artery originates below the horizontal plane of the inner curvature of the aortic arch) in the setting of an elongated aorta in this patient may explain the absence of cerebral embolization. This could possibly be relevant in combination with the centrally located floating vegetation, which was ejected along the strong central flow stream and consequently embolized to the abdominal organs. However, this excludes a generalization of the statement, and therefore the classic surgical principle of early surgery in patients with huge floating vegetations should be applied in similar cases.

CONCLUSIONS: This case illustrates the embolic potential of large, mobile vegetations in TAVR-associated endocarditis and supports early surgical intervention in accordance with both American and European infective endocarditis guidelines. The absence of cerebral embolization in the presence of massive systemic emboli should not be mistaken for anatomical protection.

PMID:42298723 | DOI:10.1186/s13019-026-04338-9

J Cardiothorac Surg. 2026 Jun 5;21(1):338. doi: 10.1186/s13019-026-04318-z.

ABSTRACT

BACKGROUND: The UFO procedure is an established surgical technique to treat extensive endocarditis of the aortic or mitral valve with involvement of the intervalvular fibrous body (IVFB). This technique can be used for radical resection of the whole infected tissue. Independently of the size of the infected region it is unavoidable to replace both valves. In this high-risk re-do case we performed a modified so-called hemi-UFO procedure with preservation of the mitral valve. We present a 71-year-old male patient initially diagnosed with severe stenosis of the aortic valve. An aortic valve replacement with a 23-mm prosthesis was performed via partial upper mini-sternotomy. Eight weeks after surgery an echocardiogram revealed a large vegetation and severe regurgitation of the aortic valve prosthesis. The risk of death following reintervention heart surgery (EuroSCORE II) was calculated as 50.64%. We performed a re-do with full sternotomy. Intraoperatively it was observed that the aortic prosthesis was partially torn out. The aortic annulus exhibited circular infection with an abscess connecting to the left atrium. The tissue of the left atrial roof was partially destroyed, similar to a phlegmonous infection. We opened the left atrial roof and radically resected the infected tissue up to the IVFB. We prepared a custom-made conduit prosthesis of bovine pericardium with a 25-mm valve prosthesis. We replaced two thirds of the ascending aorta with re-implantation of the coronary arteries using the Bentall-de Bono technique. We were able to stabilise and implant the new aortic valve prosthesis with sutures through the opened left atrial roof. The stitches began close to the anterior mitral leaflet region and ended in the direction of the left ventricle outflow tract. All sutures were pericardium-pledgeted and were passed through a bovine pericardial patch. This patch formed a new mitral annulus and was used for the closure of the left atrial roof. We had to reconstruct the IVFB, the roof of the left atrium and the mitral annulus in the anterior (A1), middle (A2) and posterior (A3) segments. The patient was transferred to the intensive care unit with no inotropes and in sinus rhythm. The 3-year follow-up was uneventful.

CONCLUSION: We showed a successful surgical treatment of aortic prosthesis endocarditis with involvement of the IVFB. We were able to perform a radical resection of the infected tissue, reconstruct and replaced all sacrificed tissue with biological tissue and preserved the native mitral valve in a modified hemi-UFO procedure.

PMID:42249393 | PMC:PMC13244841 | DOI:10.1186/s13019-026-04318-z

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

Pediatr Surg Int. 2026 May 19;42(1):236. doi: 10.1007/s00383-026-06441-3.

ABSTRACT

PURPOSE: We aimed to investigate whether pledget presence, pledget composition, and full versus partial thickness suture technique affect the force esophageal tissue can withstand before tearing.

METHODS: A right thoracotomy was performed on 10 deceased fetal sheep, 110-114 days gestation. The esophagus was divided at the level of the carina and 2 cm of tissue was removed to mimic long-gap esophageal atresia. The pouches were sutured with horizontal mattress non-absorbable braided polyester suture using one of three methods: polytetrafluoroethylene (PTFE) pledgets, bovine pericardial pledgets, or no pledget, in full or partial thickness manner. Each suture was attached to a tensiometer and manually tightened at 50 gram-force / 30 s. Maximal force before esophageal tearing and time to tearing were measured. Results were compared using a linear mixed model.

RESULTS: PTFE pledgets withstood significantly more force than pericardial pledgets (p = 0.029) and provided longer duration before tearing compared to no pledget (p = 0.017) and pericardial pledgets (p = 0.047). Full versus partial-thickness technique made no difference.

CONCLUSION: In a deceased fetal lamb long-gap esophageal atresia model, PTFE pledgets improved tissue resistance to tearing (PTFE > pericardial) and prolonged stretch duration (PTFE > pericardial or no pledget). Suture thickness (full vs. partial) made no difference.

PMID:42154275 | DOI:10.1007/s00383-026-06441-3