Generation of a novel ex-vivo model to study re-endothelialization.

Endothelial dysfunction initiates the pathogenesis of a myriad of cardiovascular diseases, yet the precise underlying mechanisms remain unclear. Current model utilises mechanical denudation of arteries resulting in an arterial-injury model with onset of intimal hyperplasia (IH). Our study shows that 5 min enzymatic denudation of human umbilical artery (hUA) lumen at 37 °C efficiently denudes hUA while maintaining vessel integrity without significantly increase intima-media thickness after 7 days in culture. This ex-vivo model will be a valuable tool in understanding the mechanism of re-endothelialization prior to smooth muscle cells (SMC) activation thus placating IH at an early stage.

E arly S u p ervised I ncremental R esistance T raining (ESpIRiT) following cardiac surgery via a median sternotomy: a study protocol of a multicentre randomised controlled trial.

INTRODUCTION: There is no consistency in current practice pertaining to the prescription and progression of upper limb resistance exercise following cardiac surgery via median sternotomy. The aim of this study is to investigate whether less restrictive sternal precautions with the addition of early-supervised resistance training exercise improves upper limb function and facilitates recovery following median sternotomy. METHODS AND ANALYSIS: This is double-blind randomised controlled trial, with parallel group, concealed allocation, blinding of patients and assessors, and intention-to-treat analysis. 240 adult participants who had median sternotomy from eight hospitals in Malaysia will be recruited. Sample size calculations were based on the unsupported upper limb test. All participants will be randomised to receive either standard or early supervised incremental resistance training. The primary outcomes are upper limb function and pain. The secondary outcomes will be functional capacity, multidomain recovery (physical and psychological), length of hospital stay, incidence of respiratory complications and quality of life. Descriptive statistics will be used to summarise data. Data will be analysed using the intention-to-treat principle. The primary hypothesis will be examined by evaluating the change from baseline to the 4-week postoperative time point in the intervention arm compared with the usual care arm. For all tests to be conducted, a p value of <0.05 (two tailed) will be considered statistically significant, and CIs will be reported. The trial is currently recruiting participants. ETHICS AND DISSEMINATION: The study was approved by a central ethical committee as well as the local Research Ethics Boards of the participating sites (UKM:JEP-2019-654; Ministry of Health: NMMR-50763; National Heart Centre: IJNREC/501/2021). Approval to start was given prior to the recruitment of participants commencing at any sites. Process evaluation findings will be published in peer-reviewed journals and presented at relevant academic conferences. TRIAL REGISTRATION NUMBER: International Standard Randomised Controlled Trials Number (ISRCTN17842822).

Retrospective review comparing intrapleural fibrinolytic therapy (alteplase) and surgical intervention in complex pleural effusion.

BACKGROUND: Intrapleural fibrinolytic therapy (IPFT) is one of the treatment options for complex pleural effusion. In this study, the IPFT agent used was alteplase, a tissue plasminogen activator (t-PA). This study aims to determine the difference in the outcome of patients with complex pleural effusion between IPFT and surgery in terms of radiological improvement, inflammatory parameters, length of stay, and post-intervention complications. METHODS: A retrospective review of patients with complex pleural effusion treated at Universiti Kebangsaan Malaysia Medical Center from January 2012 to August 2020 was performed. Patient demographics, chest imaging, drainage chart, inflammatory parameters, length of hospital stay, and post-intervention and outcome were analyzed. RESULTS: Fifty-eight patients were identified (surgical intervention, n = 18; 31% and IPFT, n = 40, 69%). The mean age was 51.7 ± 18.2 years. Indication for surgical intervention was pleural infection (n = 18; 100%), and MPE (n = 0). Indications for IPFT was pleural infection (n = 30; 75%) and MPE (n = 10; 25%). The dosages of t-PA were one to five doses of 2-50 mg. The baseline chest radiograph in the IPFT group was worse than in the surgical intervention group. (119.96 ± 56.05 vs. 78.19 ± 55.6; p = 0.029) At week 1, the radiological success rate for IPFT and surgical intervention were 27% and 20%, respectively, and at weeks 4-8, the success rate was 56% and 80% respectively. IPFT was associated with lesser complications; fever (17.5%), chest pain (10%), and non-life-threatening bleeding (5%). CONCLUSION: IPFT was comparable to surgery in radiological outcome, inflammatory parameters, and length of stay with lesser reported complications.

Incidental finding of congenital pericardial defect during vats bullectomy. Tips and tricks to avoid blunder.

The absence of a small portion of the pericardium is termed pericardial defect. This rare entity can be either acquired or congenital. The prevalence of congenital pericardial defect is exceedingly rare, which is approximately 0.002-0.004% of surgical and pathologic series. The most common type is the absence of the entire left side of pericardium, seen in 67% of all patients with a congenital pericardial defect. Other varieties are incredibly uncommon. Congenital pericardial defect has a male preponderance with a male to female ratio of 3:1, and familial occurrence is uncommon. We report a case of left partial congenital pericardial defect detected incidentally in a 22-year-old man who presented with recurrent left spontaneous pneumothorax. He underwent video-assisted thoracoscopic bullectomy and intraoperatively, we discovered a left partial pericardial defect which exposed the left atrial appendage. Although generally asymptomatic, patients may present with non-specific cardiac symptoms such as atypical chest pain. Partial pericardial defects have an increased risk of herniation of the whole left atrium, the left atrial appendage or the ventricles. If this occurs, cardiac strangulation may occur, leading to necrosis and sudden death. Cardiac MRI is a sensitive tool and will demonstrate the absence of preaortic pericardial recess. In conclusion, no surgical intervention is required in cases of congenital pericardial defect, unless the patient is symptomatic due to complications. If detected incidentally during cardiac or thoracic surgery, the best may be to leave it alone.

Coatings in Decellularized Vascular Scaffolds for the Establishment of a Functional Endothelium: A Scoping Review of Vascular Graft Refinement.

Developments in tissue engineering techniques have allowed for the creation of biocompatible, non-immunogenic alternative vascular grafts through the decellularization of existing tissues. With an ever-growing number of patients requiring life-saving vascular bypass grafting surgeries, the production of functional small diameter decellularized vascular scaffolds has never been more important. However, current implementations of small diameter decellularized vascular grafts face numerous clinical challenges attributed to premature graft failure as a consequence of common failure mechanisms such as acute thrombogenesis and intimal hyperplasia resulting from insufficient endothelial coverage on the graft lumen. This review summarizes some of the surface modifying coating agents currently used to improve the re-endothelialization efficiency and endothelial cell persistence in decellularized vascular scaffolds that could be applied in producing a better patency small diameter vascular graft. A comprehensive search yielding 192 publications was conducted in the PubMed, Scopus, Web of Science, and Ovid electronic databases. Careful screening and removal of unrelated publications and duplicate entries resulted in a total of 16 publications, which were discussed in this review. Selected publications demonstrate that the utilization of surface coating agents can induce endothelial cell adhesion, migration, and proliferation therefore leads to increased re-endothelialization efficiency. Unfortunately, the large variance in methodologies complicates comparison of coating effects between studies. Thus far, coating decellularized tissue gave encouraging results. These developments in re-endothelialization could be incorporated in the fabrication of functional, off-the-shelf alternative small diameter vascular scaffolds.

Molecular Action of Hydroxytyrosol in Attenuation of Intimal Hyperplasia: A Scoping Review.

Objective: Hydroxytyrosol (HT), a polyphenol of olive plant is well known for its antioxidant, anti-inflammatory and anti-atherogenic properties. The aim of this systematic search is to highlight the scientific evidence evaluating molecular efficiency of HT in halting the progression of intimal hyperplasia (IH), which is a clinical condition arises from endothelial inflammation. Methods: A systematic search was performed through PubMed, Web of Science and Scopus, based on pre-set keywords which are Hydroxytyrosol OR 3,4-dihydroxyphenylethanol, AND Intimal hyperplasia OR Neointimal hyperplasia OR Endothelial OR Smooth muscles. Eighteen in vitro and three in vitro and in vivo studies were selected based on a pre-set inclusion and exclusion criteria. Results: Based on evidence gathered, HT was found to upregulate PI3K/AKT/mTOR pathways and supresses inflammatory factors and mediators such as IL-1ß, IL-6, E-selectin, P-selectin, VCAM-1, and ICAM-1 in endothelial vascularization and functioning. Two studies revealed HT disrupted vascular smooth muscle cells (SMC) cell cycle by dephosphorylating ERK1/2 and AKT pathways. Therefore, HT was proven to promote endothelization and inhibit vascular SMCs migration thus hampering IH development. However, none of these studies described the effect of HT collectively in both vascular endothelial cells (EC) and SMCs in IH ex vivo model. Conclusions: Evidence from this concise review provides an insight on HT regulation of molecular pathways in reendothelization and inhibition of VSMCs migration. Henceforth, we propose effect of HT on IH prevention could be further elucidated through in vivo and ex vivo model.

Location and Patterns of Persistent Pain Following Cardiac Surgery.

OBJECTIVES: To investigate the specific clinical features of pain following cardiac surgery and evaluate the information derived from different pain measurement tools used to quantify and describe pain in this population. METHODS: A prospective observational study was undertaken at two tertiary care hospitals in Australia. Seventy-two (72) adults (mean age, 63±11 years) were included following cardiac surgery via a median sternotomy. Participants completed the Patient Identified Cardiac Pain using numeric and visual prompts (PICP), the McGill Pain Questionnaire-Short Form version 2 (MPQ-2) and the Medical Outcome Study 36-item version 2 (SF-36v2) Bodily Pain domain (BP), which were administered prior to hospital discharge, 4 weeks and 3 months postoperatively. RESULTS: Participants experienced a high incidence of mild (n=45, 63%) to moderate (n=22, 31%) pain prior to discharge, which reduced at 4 weeks postoperatively: mild (n=28, 41%) and moderate (n=5, 7%) pain; at 3 months participants reported mild (n=14, 20%) and moderate (n=2, 3%) pain. The most frequent location of pain was the anterior chest wall, consistent with the location of the surgical incision and graft harvest. Most participants equated "pressure/weight" to "aching" or a "heaviness" in the chest region (based on descriptor of pain in the PICP) and the pain topography was persistent at 4 weeks and 3 months postoperatively. Each pain measurement tool provided different information on pain location, severity and description, with significant change (p<0.005) over time. CONCLUSION: Mild-to-moderate pain was frequent after sternotomy, improved over time and was mostly located over the incision and mammary (internal thoracic) artery harvest site. Persistent pain at 3 months remained a significant problem in the community within this surgical population.

The Effects of Pro-Inflammatory and Anti-Inflammatory Agents for the Suppression of Intimal Hyperplasia: An Evidence-Based Review.

Anti-atherogenic therapy is crucial in halting the progression of inflammation-induced intimal hyperplasia. The aim of this concise review was to methodically assess the recent findings of the different approaches, mainly on the recruitment of chemokines and/or cytokine and its effects in combating the intimal hyperplasia caused by various risk factors. Pubmed and Scopus databases were searched, followed by article selection based on pre-set inclusion and exclusion criteria. The combination of keywords used were monocyte chemoattractant protein-1 OR MCP-1 OR TNF-alpha OR TNF-α AND hyperplasia OR intimal hyperplasia OR neointimal hyperplasia AND in vitro. These keywords combination was incorporated in the study and had successfully identified 77 articles, with 22 articles were acquired from Pubmed, whereas 55 articles were obtained from Scopus. However, after title screening, only twelve articles meet the requirements of defined inclusion criteria. We classified the data into 4 different approaches, i.e., utilisation of natural product, genetic manipulation and protein inhibition, targeted drugs in clinical setting, and chemokine and cytokines induction. Most of the articles are working on genetic manipulation targeted on specific pathway to inhibit the pro-inflammatory factors expression. We also found that the utilisation of chemokine- and cytokine-related treatments are emerging throughout the years. However, there is no study utilising the combination of approaches that might give a better outcome in combating intimal hyperplasia. Hopefully, this concise review will provide an insight regarding the usage of different novel approaches in halting the progression of intimal hyperplasia, which serves as a key factor for the development of atherosclerosis in cardiovascular disease.

Selection of an appropriate left-sided double-lumen tube size for one-lung ventilation among Asians.

CONTEXT: Selecting an appropriate size double-lumen tube (DLT) for one-lung ventilation has always been a challenge as most choose it based on experience or using the existing guidelines based on gender and height. AIMS: The aim of this study was to determine if the appropriate choice of this tube could be based on the patients' height, weight, tracheal diameter (TD), or the left main stem bronchus diameter (LMBD) and also to determine the relationship between height and depth of insertion among Asians. SUBJECTS AND METHODS: This was a retrospective review of 179 patients who were intubated with a left-sided DLT and also had a posterior-anterior view of a digital chest radiograph for tracheal and left main bronchus diameter measurements. Additional data collected included patients' demographics and DLT size used. RESULTS: There were 123 (68.7%) males and 56 (31.3%) females with an overall mean age of 33.3 ± 16.3 years. Majority of the males (48.8%) used a size 39 Fr while females (46.4%) used a 35 Fr. There were weak correlations between DLT size with height (male: R2 = 0.222; female: R2 = 0.193), DLT size with weight (male: R2 = 0.109; female: R2 = 0.211), DLT size with TD (male: R2 = 0.027); female: R2 = 0.016), and DLT size with LMBD (male: R2 = 0.222; female: R2 = 0.193). There was a good correlation between depth of DLT inserted with patient's height for both genders. CONCLUSION: The appropriate size of the left-sided DLT could not be predicted based on patients' height, weight, tracheal or left main bronchus diameter alone in Asians; however, the depth of insertion of the tube was dependent on the height in both genders.

Cardiomyogenic differentiation of human sternal bone marrow mesenchymal stem cells using a combination of basic fibroblast growth factor and hydrocortisone.

The alarming rate of increase in myocardial infarction and marginal success in efforts to regenerate the damaged myocardium through conventional treatments creates an exceptional avenue for cell-based therapy. Adult bone marrow mesenchymal stem cells (MSCs) can be differentiated into cardiomyocytes, by treatment with 5-azacytidine, thus, have been anticipated as a therapeutic tool for myocardial infarction treatment. In this study, we investigated the ability of basic fibroblastic growth factor (bFGF) and hydrocortisone as a combined treatment to stimulate the differentiation of MSCs into cardiomyocytes. MSCs were isolated from sternal marrow of patients undergoing heart surgery (CABG). The isolated cells were initially monitored for the growth pattern, followed by characterization using ISCT recommendations. Cells were then differentiated using a combination of bFGF and hydrocortisone and evaluated for the expression of characteristic cardiac markers such as CTnI, CTnC, and Cnx43 at protein level using immunocytochemistry and flow cytometry, and CTnC and CTnT at mRNA level. The expression levels and pattern of the cardiac markers upon analysis with ICC and qRT-PCR were similar to that of 5-azacytidine induced cells and cultured primary human cardiomyocytes. However, flow cytometric evaluation revealed that induction with bFGF and hydrocortisone drives MSC differentiation to cardiomyocytes with a marginally higher efficiency. These results indicate that combination treatment of bFGF and hydrocortisone can be used as an alternative induction method for cardiomyogenic differentiation of MSCs for future clinical applications.

Chest tube entrapment: a simple solution for technical error.

Unrecognized chest tube entrapment by surgical closure is a technical error. We present a rare case of chest tube entrapment that was successfully treated with a simple and safe solution in an elderly man after coronary artery bypass grafting (CABG). We visualized the suture using a small endoscope through the chest tube and incised it with the help of thoracoscopic scissors. The tube was then removed without the need for surgical exploration.

Pedunculated parietal pleural lesion: a rare presentation of bronchogenic cyst.

We present a 35-year-old man with a preoperative diagnosis of a right lower lobe cystic mass. Misled by a radiological suggestion of an intraparenchymal lesion, he had a thoracotomy and right lower lobectomy. An intraoperative finding of a pedunculated cyst arising from the parietal pleural with subsequent histopathology confirmation of a benign bronchogenic cyst, however, would have made a less invasive surgical excision more appropriate.

Bismuth paste injection for empyema thoracis: a 100-year-old method revisited.

Bismuth paste injection into the pleural cavity used to be a treatment for chronic empyema thoracis. This method, however, was long forgotten and scarcely practiced due to advanced surgical techniques and antibiotic therapy. We report a 50-year-old man with chronic empyema thoracis who was successfully treated with bismuth paste injection after a failed surgical decortication and a long-term chest drainage. This case highlights a trial of a 100-year-old method of bismuth paste injection which proved effective after standard measures had failed.

Chest tube injury to left ventricle: complication or negligence?

An injury to the left ventricle after a chest tube insertion is a rare but lethal phenomenon that is likely to occur if precautions are not seriously addressed. We present a 15-year-old girl who was diagnosed a left empyema thoracis. An attempt to place a chest drain in this young girl was almost fatal. A left ventricular repair together with thoracotomy and decortication were successful. This case emphasizes the rarity of this lethal complication and the importance of the correct technique for chest tube insertion.

Pocket-sized Heimlich valve (Pneumostat) after bullae resection: a 5-year review.

PURPOSE: This study was conducted to evaluate the practicability, effectiveness, and potential complications of a newly improvised pocket-sized Heimlich valve named the Pneumostat (Atrium Medical Corp, Hudson, NH). DESCRIPTION: This was a retrospective review of 98 patients who underwent bullae resection after recurrent spontaneous pneumothorax at our center from January 2002 until June 2007. Data from the patients' files were collected and analyzed. EVALUATION: The mean age of the patients was 28.5 years (range, 17 to 52). There were 80.6% smokers and 5.1% diabetics. Pneumostat (Atrium Medical Corp) was inserted and the patients started to ambulate on day 1 after surgery. The mean hospital stay was 3.08 days. The mean duration of the affected lung to fully expand and the drain to be removed was 7.5 days. No other complications occurred, apart from drain site wound infection in 4.1% of the patients, which resolved with oral antibiotics and simple wound care. CONCLUSIONS: This review proved that the pocket-sized Pneumostat was safe and practical in this group of patients. It improved the patients' recovery in terms of mobilization and reduced the length of hospital stays with no significant complications.

Comminuted sternal fracture -- a sternotomy wire fixation: report of 2 cases.

Various techniques of sternal stabilization via either metal plates or wires have been described. We describe an alternative technique of simple median sternotomy followed by reduction and wire fixation of the sternal fracture. The 2 patients described in this report had traumatic comminuted and displaced sternal fractures. Even though wire repair was deemed to be tedious and achieved poor approximation of the bone, we performed median sternotomy and achieved simple wire fixation with an excellent result.