Short-Term Clinical Outcomes of Transcatheter Aortic Valve Replacement in a Developing Country.

INTRODUCTION: Transcatheter aortic valve replacement (TAVR) is an effective alternative to surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis in all surgical risk groups. Reports of clinical outcomes post-TAVR in developing countries are scarce. We aimed to address the clinical outcomes and safety profile of TAVR in a developing country. METHODS: We conducted a single-center, retrospective study on patients undergoing TAVR at the American University of Beirut Medical Center (AUBMC) from January 2016 to April 2023. We included a total of 399 patients. Our primary endpoint was to assess the rate of TAVR in-hospital and 30-day mortality, neurologic events, and new permanent pacemaker implantation (PPI) in patients, stratified by the Society of Thoracic Surgeons (STS) risk of mortality score. RESULTS: Survival rates were 98.7% (394) at discharge vs. 97.5% (389) at 30 days post-procedure. The technical success rate was 95% (379) at the end of the procedure. Device success and early safety rates were 93.5% (373) and 83% (331), respectively at 30 days post-procedure. The all-cause mortality rate increased from 1.3% (5) at discharge to 2.5% (10) at 30-day intervals. The rate of ischemic stroke was 1.3% (five) at discharge and increased to 2% (eight) at 30 days post-procedure. PPI was needed in 5.8% (23) of patients at discharge with an increase to 7% (28) at one-month interval. Overall, the rates of TAVR outcomes among the three risk groups were comparable including neurologic events, valve-related complications, bleeding problems, vascular and access-related complications, and myocardial infarction. CONCLUSION: This study at AUBMC highlights the successful implementation of the TAVR program in a developing country, showcasing its efficacy and safety within 30 days post-operation, despite challenges such as financial constraints and limited access to specialized training. Larger cohorts and longer follow-up periods are needed to accurately represent clinical outcomes in developing countries.

Pediatric Traumatic Brain Injury in the Middle East and North Africa Region: A Systematic Review and Meta-Analysis to Assess Characteristics, Mechanisms, and Risk Factors.

Pediatric traumatic brain injury (pTBI) represents a major cause of child injuries in the Middle East and North Africa (MENA) region. This review aims to assess pTBIs in the MENA region and reports their clinical severity and outcomes. A search was conducted using major electronic databases, including Medline/Ovid, PubMed, EMBASE, Web of Science, and SCOPUS. Abstracts were screened independently and in duplicate to detect original research. The objective and study findings for each article were recorded, along with the mechanism of pTBI, patient age and sex, injury assessment tool(s) used, and outcome. A total of 1345 articles were retrieved, of which 152 met the criteria for full-text review, and 32 were included in this review. Males predominantly suffered from pTBIs (78%). Motor vehicle accidents, followed by child abuse, were the leading causes of pTBI. Overall, 0.39% of cases were mild, 0.58% moderate, 16.25% severe, and 82.27% unclassified. The mortality rate was 13.11%. Most studies used the computed tomography scan, Glasgow Coma Scale, Abbreviated Injury Scale, and Injury Severity Score as investigation methods. This review reports on the alarming rate of child-abuse-related pTBI and offers further understanding of pTBI-associated risk factors and insight into the development of strategies to reduce their occurrence, as well as policies to promote child well-being.

Air-loaded Gas Vesicle Nanoparticles Promote Cell Growth in Three-dimensional Bioprinted Tissue Constructs.

Three-dimensional (3D) bioprinting has emerged as a promising method for the engineering of tissues and organs. Still, it faces challenges in its widespread use due to issues with the development of bioink materials and the nutrient diffusion barrier inherent to these scaffold materials. Herein, we introduce a method to promote oxygen diffusion throughout the printed constructs using genetically encoded gas vesicles derived from haloarchaea. These hollow nanostructures are composed of a protein shell that allows gases to permeate freely while excluding the water flow. After printing cells with gas vesicles of various concentrations, the cells were observed to have increased activity and proliferation. These results suggest that air-filled gas vesicles can help overcome the diffusion barrier throughout the 3D bioprinted constructs by increasing oxygen availability to cells within the center of the construct. The biodegradable nature of the gas vesicle proteins combined with our promising results encourage their potential use as oxygen-promoting materials in biological samples.

Preparation and printability of ultrashort self-assembling peptide nanoparticles.

Nanoparticles (NPs) have left their mark on the field of bioengineering. Fabricated from metallic, magnetic, and metal oxide materials, their applications include drug delivery, bioimaging, and cell labeling. However, as they enter the body, the question remains - where do they go after fulfilling their designated function? As most materials used to produce NPs are not naturally found in the body, they are not biodegradable and may accumulate overtime. There is a lack of comprehensive, long-term studies assessing the biodistribution of non-biodegradable NPs for even the most widely studied NPs. There is a clear need for NPs produced from natural materials capable of degradation in vivo. As peptides exist naturally within the human body, their non-toxic and biocompatible nature comes as no surprise. Ultrashort peptides are aliphatic peptides designed with three to seven amino acids capable of self-assembling into helical fibers within macromolecular structures. Using a microfluidics flow-focusing approach, we produced different peptide-based NPs that were then three-dimensional (3D) printed with our novel printer setup. Herein, we describe the preparation method of NPs from ultrashort self-assembling peptides and their morphology in both manual and 3D-printed hydrogels, thus suggesting that peptide NPs are capable of withstanding the stresses involved in the printing process.