Pericardial Patch Research Articles

Posterior Skirt Technique with Mitral Valve Replacement for Mitral Annular Calcification

AbstractSevere mitral annular calcification (MAC) presents a surgical challenge due to the complexity of disease and the risk of valve replacement. There have been a variety of techniques to combat this risk including edge-to-edge repair, collar-enforced prosthesis, and pericardial patch techniques. This report highlights a case in which a novel reproducible surgical technique was used to prevent perivalvular leak with mitral valve replacement. This technique may add to surgeons' repertoire in addressing patients with MAC concentrated on the posterior annulus.

Acellular Bovine Pericardial Patch for Difficult Abdominal Closure in the Pediatric Population: Our Experience with Review of Literature.

Closure of congenital body wall defects in children can be a challenging task for the pediatric Surgeon. Biological prosthesis has been increasingly used for high-risk wound closure in adult patients with excellent outcomes and use in the pediatric population has also been reported. Here, we aim to study the outcome of abdominal wound repair with a tissue-engineered acellular bovine pericardial patch. Over a period of 21 months, a total of 15 children had undergone abdominal wound repair with bioprostheses, i.e., bovine pericardial patch at our institute. Patient demographics, cause of defect, an indication of patch use, rate of infection, postoperative recovery, recurrence, and outcome were studied. A total of 15 patients underwent abdominal wall closure with acellular bovine pericardial patch. Nine out of 15 patients were neonates, of whom five had gastroschisis, two had a congenital diaphragmatic hernia, and two had ruptured omphalocele major. Of the rest 6 patients, 2 were patients of bladder exstrophy, 2 were older children of congenital diaphragmatic hernia with incisional hernias, and 2 were older children with omphalocele major. Out of the five patients with gastroschisis, two died during the early postoperative period due to sepsis. The wound healed in the rest 13 patients with mild skin dehiscence in two patients. Only one child had a recurrence. Reconstruction with acellular bovine pericardial patch is a viable option in children with high-risk abdominal wounds as it allows tensionless repair with excellent healing and minimal complications. Recurrence, if any, may disappear with time as remodeling of the prosthesis occurs along with the growth of the body wall of the child.

Tricuspid valve repair for infective endocarditis.

The progressive increase in the use of implantable electronic devices, vascular access for dialysis and the increased life expectancy of patients with congenital heart diseases has led in recent years to a considerable number of right-side infective endocarditis, especially of the tricuspid valve (TV). Although current guidelines recommend TV repair for native tricuspid valve endocarditis (TVE), the percentage of valve replacements remains very high in numerous studies. The aim of our study is to analyse our experience in the treatment of TVE with a reparative approach. This case series includes all the patients who underwent surgery for acute or healed infective endocarditis on the native TV, at the Cliniques Universitaires Saint-Luc (Bruxelles, Belgium) between February 2001 and December 2020. Thirty-one patients were included in the study. Twenty-eight (90.3%) underwent TV repair and 3 (9.7%) had a TV replacement with a mitral homograft. The repair group was divided into 2 subgroups, according to whether a patch was used during surgery or not. Hospital mortality was 33.3% (n = 1) for the replacement group and 7.1% (n = 2) for repair (P = 0.25). Overall survival at 10 years was 75.6% [95% confidence interval (CI): 52-89%]. Further, freedom from reoperation on the TV at 10 years was 59.3% (95% CI: 7.6-89%) vs 93.7% (95% CI: 63-99%) (P = 0.4) for patch repair and no patch use respectively. Freedom from recurrent endocarditis at 10 years was 87% (95% CI: 51-97%). Considering that TVE is more common in young patients, a repair-oriented approach should be considered as the first choice. In the case of extremely damaged valves, the use of pericardial patch is a valid option. If repair is not feasible, the use of a mitral homograft is an additional useful solution to reduce the prosthetic material.

Implementation of an epicardial implantable MEMS sensor for continuous and real-time postoperative assessment of left ventricular activity in adult minipigs over a short- and long-term period.

The sensing of left ventricular (LV) activity is fundamental in the diagnosis and monitoring of cardiovascular health in high-risk patients after cardiac surgery to achieve better short- and long-term outcome. Conventional approaches rely on noninvasive measurements even if, in the latest years, invasive microelectromechanical systems (MEMS) sensors have emerged as a valuable approach for precise and continuous monitoring of cardiac activity. The main challenges in designing cardiac MEMS sensors are represented by miniaturization, biocompatibility, and long-term stability. Here, we present a MEMS piezoresistive cardiac sensor capable of continuous monitoring of LV activity over time following epicardial implantation with a pericardial patch graft in adult minipigs. In acute and chronic scenarios, the sensor was able to compute heart rate with a root mean square error lower than 2 BPM. Early after up to 1 month of implantation, the device was able to record the heart activity during the most important phases of the cardiac cycle (systole and diastole peaks). The sensor signal waveform, in addition, closely reflected the typical waveforms of pressure signal obtained via intraventricular catheters, offering a safer alternative to heart catheterization. Furthermore, histological analysis of the LV implantation site following sensor retrieval revealed no evidence of myocardial fibrosis. Our results suggest that the epicardial LV implantation of an MEMS sensor is a suitable and reliable approach for direct continuous monitoring of cardiac activity. This work envisions the use of this sensor as a cardiac sensing device in closed-loop applications for patients undergoing heart surgery.

Alpha gal syndrome, a relative not absolute contraindication to the use of bovine pericardium to close an intracardiac septal defect: a case report

BackgroundAlpha-gal syndrome is an allergic condition in which individuals develop an immune-mediated hypersensitivity response when consuming red meat and its derived products. Its diagnosis is important in individuals undergoing cardiac surgery, as patients frequently require large doses of unfractionated heparin or the insertion of surgical implants, both of which are porcine or bovine in origin. There are currently no guidelines for heparin administration in alpha-gal patients, with even less knowledge regarding the long-term clinical implications of these patients after receiving bioprosthetic valve replacements or other prostheses.Case presentationWe present the case of a 31-year-old male who underwent cardiac surgery in the setting of alpha-gal syndrome for a large atrial septal defect (ASD) and mitral valve prolapse (MVP). The patient continues to do well one year after undergoing a mitral valve repair, tricuspid valve repair and an ASD closure using bovine pericardium. He sustained no adverse reaction to the use of heparin products or the presence of a bovine pericardial patch. This rare case was managed by a multidisciplinary team consisting of cardiothoracic surgery, cardiac anesthesiology, and allergy/immunology that led to an optimal outcome despite the patient’s pertinent allergic history.ConclusionsThis case highlights that the use of bovine pericardium and porcine heparin to close septal defects in patients with milder forms of alpha-gal allergy can be considered if other options are not available. Further studies are warranted to investigate the long-term outcomes of such potential alpha-gal containing prostheses and heparin exposure and establish the optimal decision making algorithm and prophylactic regimen.

Use of autologous pericardial patch graft for treatment of large congenital peritoneopericardial diaphragmatic hernia in two cats

AbstractPeritoneopericardial diaphragmatic hernia is a congenital structural anomaly that results in a communication between the pericardial sac and the peritoneal cavity. About 50% of cats are asymptomatic at the time of diagnosis, and the remaining animals may show respiratory (dyspnoea, tachypnoea, exercise intolerance), gastrointestinal, cardiac tamponade or non‐specific clinical signs. Median celiotomy for herniorrhaphy without tension (primary closure, muscle flaps, synthetic mesh, pericardium) is the treatment of choice for symptomatic patients. Two cats were referred with respiratory signs, secondary to a peritoneopericardial diaphragmatic hernia. A pericardial patch graft was obtained and sutured to the diaphragm as an alternative technique to close the large defect and not cause excessive tension on the diaphragm and caval foramen. Patients recovered well without any complications after surgery. Re‐examination and thoracic radiographs at 1 week, 2 weeks, 3 months, 6 months and 3 years postoperatively showed no signs of recurrence and the patients remained asymptomatic.

Delayed traumatic left ventricular pseudoaneurysm: diagnostic challenges and surgical management.

Left ventricular (LV) pseudoaneurysms are uncommon, with traumatic cases being particularly rare. We present a case of a 26-year-old male with a delayed presentation of a traumatic LV pseudoaneurysm, 2years post-blunt chest trauma. The patient experienced New York Heart Association (NYHA) grade 2 dyspnea, which prompted the investigation. Imaging studies, including X-ray, echocardiogram, and cardiac computed tomography (CT), revealed a large pseudoaneurysm arising from the LV apex, containing intramural thrombus. The surgical intervention involved the closure of the communicating orifice and on-lay pericardial patch placement. This case emphasizes the diagnostic challenges and successful management of traumatic LV pseudoaneurysms. Early detection through imaging and prompt surgical intervention led to a favorable outcome. This report contributes to understanding post-traumatic pseudoaneurysms and underscores the importance of a multidisciplinary approach in their management. Further studies are needed to refine diagnostic and treatment strategies for this rare condition.

Evaluation of pericardium patch graft thickness in patients with Ahmed glaucoma valve implantation: an anterior segment OCT study

PurposeTo evaluate the changes in thickness of tissues, specifically the pericardium patch graft (PPG) covering the silicone tube in Ahmed Glaucoma Valve (AGV) surgery.Study designProspective observational study.MethodsThis study included cases with refractory glaucoma that underwent AGV implantation with PPG coverage. Conjunctival epithelium, stroma and PPG thickness covering the tube were measured using anterior segment optical coherence tomography (AS-OCT) at 1, 6 and 12 months. Additionally, the same measurements were taken 1500 µm away from the tube as a control for the central measurements.ResultsTwenty-seven eyes of 27 patients were evaluated in the study. Although PPG thickness decreased significantly in both regions, the amount of reduction was more pronounced centrally. Centrally, the reduction rate was 21.2% and 34.8% during the 1-6 months period and 6-12 months period, while peripherally it was 3.5% and 5.1%, respectively. No change was observed in the thickness of the epithelium during the follow-up period. There was a significant thinning of the stroma in the central and peripheral regions during the 1-6 months period (30.5% and 17%, respectively). No cases of exposure were observed during the follow-up period.ConclusionAlthough the most evident thinning of the layers covering the tube was observed in the early postoperative period, PPG showed a stable decrease even in the late period. The progressive reduction in the PPG thickness observed also in the peripheral region indicates that factors beyond mechanical forces contribute to this degenerative process. AS-OCT could be a valuable non-invasive tool in clarifying this process.

Twenty-five years' experience with isolated bicuspid aortic valve repair: impact of commissural orientation.

Repair of the bicuspid aortic valve has evolved in the past 25 years. The aim of this study was to review and analyze the long-term durability of isolated BAV repair with particular focus on commissural orientation (CO). All patients who underwent bicuspid aortic valve repair for severe aortic regurgitation between 10/1998 and 12/2022 were included. The study group consists of all patients operated after 2009 ie, since CO modification. The control group includes patients who were operated before 2009. Commissural orientation was classified as symmetric, asymmetric, and very asymmetric. Overall, 594 adult patients (93% male; mean age 42 years) were included. At 15 years, survival was 94.8% (SD : 2.2); freedom from reoperation was 86.8% (SD : 2.3). Freedom from AI≥II was 70.8% (SD : 4.7) at 15 years. Modification of commissural orientation by sinus plication was performed in 200 (33.7%) instances. Using competing risks analysis, the absence of eH measurement (P = 0.018), very asymmetric CO (P = 0.028), the presence of calcification (P < 0.001), the use of pericardial patch (P < 0.001), the use of subcommissural sutures (P < 0.001), and preoperative endocarditis (P = 0.005) were identified as independent predictors for reoperation. Follow-up was 97% complete (4228 patient-years); mean follow-up was 7 years (SD : 5). Isolated bicuspid aortic valve repair leads to good survival and durability in all morphologic types if cusp repair is guided by effective height, suture annuloplasty is performed, and CO is modified using sinus plication in asymmetrical valves. Very asymmetrical valves may should be treated with a lower threshold for replacement.

Unusual presentation and delayed diagnosis of cardiac angiosarcoma

BackgroundPrimary cardiac angiosarcomas are very rare and present aggressively with high rates of metastasis. Given the poor prognosis, particularly once disease has spread, early diagnosis and multidisciplinary treatment is essential.Case presentationWe present the case of a 46-year-old male who presented with chest pain, intermittent fevers, and dyspnea. Workup with computed tomography scan and transesophageal echocardiography demonstrated a right atrial pseudoaneurysm. Given the concern for rupture, the patient was taken to the operating room, where resection of the pseudoaneurysm and repair using a bovine pericardial patch was performed. Histopathology report initially demonstrated perivascular lymphocyte infiltrate. Six weeks later, the patient represented with chest pain and new word finding difficulty. Workup revealed multiple solid lung, pericardial, brain, and bone nodules. Eventual biopsy of a cardiophrenic nodule demonstrated angiosarcoma, and rereview of the original pathology slides confirmed the diagnosis of primary cardiac angiosarcoma.ConclusionsPrimary cardiac angiosarcomas are often misdiagnosed given the rarity of these tumors, but early diagnosis and initiation of treatment is essential. The unique presentation of our case demonstrates that clinical suspicion for cardiac angiosarcoma should be maintained for spontaneous pseudoaneurysm originating from the right atrium.

Surgical outcomes of patients with inferior vena cava leiomyosarcoma

IntroductionPrimary vascular leiomyosarcomas are incredibly rare and have a poor prognosis. The purpose of this study was to analyze the surgical outcomes of patients with primary inferior vena cava (IVC) leiomyosarcoma. MethodsWe performed a retrospective review of IVC leiomyosarcoma resections performed at a single tertiary care hospital from 2014 to 2023. A total of 13 cases were analyzed, including 10 women and 3 men. The presenting symptoms, tumor characteristics, operative management, postoperative complications, and survival rates were assessed for each patient. ResultsThe median patient age was 59 years (quartile [Q]1, 52 years; Q3, 68 years). The median tumor size was 7.0 cm (Q1, 6 cm; Q3, 12 cm). The median mitotic rate was 6 per 10 high-power fields (Q1, 2.5; Q3, 15.5). All 13 patients underwent grossly negative tumor resection, with 9 (69%) having microscopically negative margins (R0). No patient had lymph node involvement. The IVCs were managed with ligation in four patients for tumors already occluding the IVC and bovine pericardial patch angioplasty in seven patients or primary repair in two patients for patent IVCs. Concomitant right nephrectomy was performed in seven patients. Left renal vein ligation was performed in three patients, but no left nephrectomies were performed. Significant postoperative complications included one patient with lower extremity compartment syndrome, two patients with severe leg swelling, and one patient with arm swelling. The 30-day mortality rate was zero. Using the Kaplan-Meier product limit method, disease-specific survival was estimated to be 93%. ConclusionsSurgical resection is a feasible and effective oncologic treatment option for patients with IVC leiomyosarcoma. The IVC can be safely managed by ligation, primary repair, or patch angioplasty, depending on the prior patency of the IVC.

Role of Pericardial Patch in Neurosurgery: Institutional Experience.

Dural closure is an important part of neurosurgery, failure which may lead to wound infection, pseudomeningoceles, meningitis, severe morbidity to a patient, and even mortality. In cases where primary dura closure is not possible, a bovine pericardial patch is a good alternative with the benefits of suturability and the ability to provide watertight closure, hence preventing Cerebrospinal Fluid (CSF) leak. The present study demonstrates the use of the bovine pericardial patch in both cranial and spinal disorders for dural closure as well as for transposition technique in microvascular decompression. The aim of our study is to understand the advantages and feasibility of a bovine pericardial patch in various neurosurgical procedures. Fifty-one patients were analyzed prospectively and followed up in which glutaraldehyde-free bovine pericardial patch was used in various cranial and spinal disorders. The most common indications where a bovine pericardial patch was used, in decreasing order of frequency, were meningioma excision surgery (47%), followed by Chiari malformation operated for foramen magnum decompression (17.6%), meningomyelocele (7.8%), spinal dural defects (7.8%), trigeminal neuralgia (5.8%), traumatic decompression with lax duraplasty (4%), glioma (4%), encephalocele (4%), and skull base defects (2%). Two patients had complications, one with CSF leak and the other had superficial wound infection, which were managed appropriately. The use of a bovine pericardial patch as a dural substitute in various cranial and spinal disorders is feasible with good outcomes, and it can be considered an ideal dural substitute.

Major vascular reconstructions in thoracic oncological surgery.

The replacement of the superior vena cava and thoracic outlet vessels for thoracic malignancies often becomes necessary for radical oncological surgery. The pulmonary artery can be directly infiltrated by the tumor or affected by metastatic hilar lymph nodes. In some cases, it must be resected and reconstructed to achieve oncological radicality and/or avoid pneumonectomy. This study reflects a single-surgeon, retrospective experience spanning 6years (2017-2023). We reviewed data from patients undergoing early anticoagulant therapy after superior vena cava or thoracic outlet vessels bypass and from patients undergoing early antiaggregation therapy following pulmonary artery reconstruction or resection. This series comprises 41 patients treated by a single surgeon. Fourteen patients underwent superior vena cava and thoracic outlet vessel procedures. Among these, eight patients received superior vena cava replacement (six for thymic malignancies and two for lung cancer), and six patients underwent jugular and subclavian artery/vein resection or replacement (all six had sarcomas). There was one death due to respiratory failure, not associated with bleeding or bypass closure. Additionally, there was one graft closure in a patient with severe coagulopathy and three instances of hemothorax (two patients had undiagnosed complex coagulopathies not evident in pre-operative routine blood tests). Following bleeding incidents, anticoagulation was initiated the next day in one case and based on hematological indications in the two coagulopathic patients. In the pulmonary artery series, 27 patients were involved: 20 underwent direct suture after tangential resection, and 7 received pericardial patch reconstruction. Only one case experienced bleeding necessitating redo-surgery. All these patients received early and chronic antiaggregation therapy after pulmonary artery reconstruction. We conclude that major thoracic oncological vascular surgery is safe and feasible with appropriate technical skills. However, achieving optimal results requires integration with correct early anticoagulant therapy or antiaggregation to maintain the patency of bypasses/grafts and prevent life-threatening risks associated with closure of the "new vessels."

Pedicled pericardial patch in tracheal reconstruction in children – Novel technique to provide vascularized tissue for salvaging difficult airways

BackgroundManagement of large central airway defects are often complex. Children who present with these defects have multiple co-morbidities or have had previous surgeries. Surgical options include various tissue cover for these defects without longer term benefits. Vascularized autologous pericardial patch offers a better solution to these defects by providing vascularity and potential for remodelling in future. Methods41 children (M:F of 24:17) were operated for large trachea-bronchial defects between January 2015 and August 2022. The median age of was 12 months with median weight of 8.9 kg (IQR 3.3 kg–17.7 kg) Causes leading to the central tracheal defect include failed repair of previous trachea-oesophageal fistula (TOF) (n = 21) and acquired fistula due to button battery injury (n = 11). Surgical repair consisted of autologous pedicled pericardial patch repair for the airway defect under cardiopulmonary bypass. ResultsThere were two operative deaths related to extensive sepsis and necrosis of reconstructed trachea. Four children had further reoperation with additional patch. Bronchoscopy was used as surveillance in all these children, with use of airway stents (biodegradable stent) in 9 children. The median ventilation time was 8 days, with tracheostomy being needed in 5 for long term support. ConclusionsAutologous pericardial patch is a versatile technique and can be used to salvage large tracheal defects when other method have failed or not feasible. Tracheomalacia at the site of repair could be managed with biodegradable stents. Vascularity and ciliary function of the patch still needs to be evaluated.

Mitral valve repair for infective endocarditis after esophageal reconstruction: a case report

BackgroundIn patients with retrosternal neo-esophageal conduit after right thoracotomy, the approach to cardiac surgery could be challenging. Particularly, in patients with infective endocarditis, there is a risk of injury to the conduit through standard median sternotomy. Moreover, right lung adhesions could be predicted. Herein, we present a case of successful mitral valve repair in a patient with infective endocarditis through a redo right thoracotomy after esophageal reconstruction.Case presentationA 66-year-old male patient was diagnosed with infective endocarditis and a large anterior mitral leaflet vegetation after a previous esophageal reconstruction via right thoracotomy for esophageal cancer. Due to the retrosternal esophageal reconstruction, we performed a mitral valve repair through a redo right thoracotomy. After resecting the vegetation, the defect was closed with a fresh autologous pericardial patch. Mitral valve annuloplasty was performed. Postoperatively, antibiotics controlled the infection. The patient was discharged on postoperative day 30.ConclusionsSuccessful mitral valve repair was performed for infective endocarditis through a redo right thoracotomy after esophageal reconstruction.

An interventional sheep model of severe aortic valve stenosis hemodynamics for the evaluation of alterations in coronary physiology and microvascular function.

We aimed to develop a large animal model of subcoronary aortic stenosis (AS) to study intracoronary and microcirculatory hemodynamics. A total of three surgical techniques inducing AS were evaluated in 12 sheep. Suturing the leaflets together around a dilator (n = 2) did not result in severe AS. Suturing of a pericardial patch with a variable opening just below the aortic valve (n = 5) created an AS which was poorly tolerated if the aortic valve area (AVA) was too small (0.38-1.02 cm2), but was feasible with an AVA of 1.2 cm2. However, standardization of aortic regurgitation (AR) with this technique is difficult. Therefore, we opted for implantation of an undersized AV-bioprosthesis with narrowing sutures on the leaflets (n = 5). Overall, five sheep survived the immediate postoperative period of which three had severe AS (one patch and two bioprostheses). The surviving sheep with severe AS developed left ventricular hypertrophy and signs of increased filling-pressures. Intracoronary assessment of physiological indices in these AS sheep pointed toward the development of functional microvascular dysfunction, with a significant increase in coronary resting flow and hyperemic coronary resistance, resulting in a significantly higher index of microvascular resistance (IMR) and lower myocardial resistance reserve (MRR). Microscopic analysis showed myocardial hypertrophy and signs of fibrosis without evidence of capillary rarefaction. In a large animal model of AS, microvascular changes are characterized by increased resting coronary flow and hyperemic coronary resistance resulting in increased IMR and decreased MRR. These physiological changes can influence the interpretation of regularly used coronary indices.NEW & NOTEWORTHY In an animal model of aortic valve stenosis (AS), coronary physiological changes are characterized by increased resting coronary flow and hyperemic coronary resistance. These changes can impact coronary indices frequently used to assess concomitant coronary artery disease (CAD). At this point, the best way to assess and treat CAD in AS remains unclear. Our data suggest that fractional flow reserve may underestimate CAD, and nonhyperemic pressure ratios may overestimate CAD severity before aortic valve replacement.

Similar long-term outcomes for venous, bovine pericardial, and polyester patches for primary carotid endarterectomy.

Currently, the type of patch used for carotid endarterectomy closure depends on the preference of the operating surgeon. Various materials are available, including autologous venous patches, bovine pericardial patches (BPP), and synthetic patches. The purpose of this study was to compare the long-term outcomes. All patients who underwent primary carotid endarterectomy with patch angioplasty using a venous, bovine, or polyester patch between 2010 and 2020 at two high-volume medical centers were included in this retrospective analysis on largely prospectively collected data. Study endpoints included long-term ipsilateral transient ischemic attack or cerebrovascular accident, restenosis, reintervention, and all-cause mortality. Cox proportional hazard models were fitted to assess the effect of patch type to each outcome. In total, 1481 CEAs were performed with a follow-up of 32 (13-65) months. Venous patch was used in 309 patients (20.9%), BPP in 1000 patients (67.5%), and polyester patch in 172 patients (11.6%). A preoperative symptomatic carotid artery stenosis of >50% was observed in 91.9% (n=284) of the patients who received a venous patch, 92.1% (n=921) of the patients who received BPP, and 90.7% (n=156) of the patients who received a polyester patch (p=0.799). Only in selected patients with an asymptomatic stenosis of >70% surgery was considered. Multivariable analyses showed no significant differences between the three patch types regarding long-term outcomes after adjusting for confounders. In patients undergoing primary carotid endarterectomy, the use of venous, bovine pericardial, or polyester patches seems equally safe and durable in terms of comparability in long-term outcomes.

[Translated article] Effects of duroplasty with bovine pericardium on fibrosis and extent of spinal cord injury: An experimental study in pigs

IntroductionTraumatic spinal cord injury (SCI) leads to increased intraspinal pressure that can be prevented by durotomy and duroplasty. The aim of the study was to evaluate fibrosis and neural damage in a porcine model of SCI after duroplasty and application of hyaluronic acid (HA) in the tissue cavity. Materials and methodsExperimental study. We created a porcine SCI model by durotomy and spinal cord hemisection of a cervical segment (1cm). Six pigs (Sus scrofa domestica) were used to evaluate three surgical scenarios: (1) control injury with dural reparative microsurgery, (2) duroplasty using bovine pericardium (BPD), and (3) previous method plus HA applied at the lesion. Animals were sacrificed one-month post-injury to assess fibrotic responses and neural tissue damage using conventional histological and immunohistochemical methods. ResultsIn the control case, dural suture prevented invasion of the lesion by extradural connective tissue, and the dura mater showed a 1-mm thickening in the perilesional area. The bovine pericardium patch blocked the entrance of extradural connective tissue, decreased dura-mater tension, and satisfactorily integrated within the receptor tissue. However, it also enhanced subdural and perilesional fibrosis, which was not inhibited by filling the lesion cavity with low- or high-molecular-weight HA. ConclusionsDuroplasty prevents collapse of the dura-mater over the spinal cord tissue, as well as invasion of the lesion by extramedullary fibrotic tissue, without creating additional neural damage. Nevertheless, it enhances the fibrotic response in the spinal cord lesion and the perilesional area. Additional antifibrotic strategies are needed to facilitate spinal cord repair.

Tissue-engineered and autologous pericardium in congenital heart surgery: comparative histopathological study of human vascular explants.

The goal of this histological study was to assess the biocompatibility of vascular patches used in the repair of congenital heart defects. We examined tissue-engineered bovine (n = 7) and equine (n = 7) patches and autologous human pericardium (n = 7), all explanted due to functional issues or follow-up procedures. Techniques like Movat-Verhoeff, von Kossa and immunohistochemical staining were used to analyse tissue composition, detect calcifications and identify immune cells. A semi-quantitative scoring system was implemented to evaluate the biocompatibility aspects, thrombus formation, extent of pannus, inflammation of pannus, cellular response to patch material, patch degradation, calcification and neoadventitial inflammation. We observed distinct material degradation patterns among types of patches. Bovine patches showed collagen disintegration and exudate accumulation, whereas equine patches displayed edematous swelling and material dissolution. Biocompatibility scores were lower in terms of cellular response, degradation and overall score for human autologous pericardial patches compared to tissue-engineered types. The extent of pannus formation was not influenced by the type of patch. Bovine patches had notable calcifications causing tissue hardening, and foreign body giant cells were more frequently seen in equine patches. Plasma cells were frequently detected in the neointimal tissue of engineered patches. Our results confirm the superior biocompatibility of human autologous patches and highlight discernible variations in the changes of patch material and the cellular response to patch material between bovine and equine patches. Our approach implements the semi-quantitative scoring of various aspects of biocompatibility, facilitating a comparative quantitative analysis across all types of patches, despite their inherent differences.

Giant Aneurysm of the Interatrial Septum: A Multidisciplinary Approach

A 46-year-old woman presented for a routine echocardiogram, which revealed a giant atrial septal aneurysm (ASA) with an atrial septal defect (ASD). We surgically excised the ASA and closed the ASD with a pericardial patch. ASA, although rare, poses embolic risks, thus necessitating closure when associated with shunts. Optimal stroke prevention remains uncertain.