Appraising critical success factors in sustainable housing projects: A comparative study of PPP modalities in Saudi Arabia.

This study examines the critical success factors (CSFs) crucial for the effective deployment of public-private partnership (PPP) models in sustainable housing projects in the Kingdom of Saudi Arabia (KSA), underpinning the nation's Vision 2030. Through a robust methodology that incorporates a profound literature review, structured interviews, and a survey involving key stakeholders, the study prioritizes fourteen significant CSFs integral to PPP efficacy. Employing Analytical Hierarchy Process analysis, key outcomes underscore the paramount importance of technical aspects with an emphasis on sustainability, tailoring risk-sharing and allocation to encompass green technologies and eco-friendly practices, and economic stability in the light of long-term environmental sustainability in fostering successful sustainable housing projects. Notably, the Build-Operate-Transfer (BOT) model is categorized as the most effective PPP modality, attaining a mean importance score of 4.07. This model is contrasted with other modalities such as Design-Build-Operate (DBO) and Build-Own-Lease-Transfer (BOLT), which scored lower in effectiveness. This comprehensive evaluation provides crucial insights for policymakers and practitioners, emphasizing the strategic selection of PPP modalities and the prioritization of CSFs to enhance the sustainability and effectiveness of housing projects in KSA.

Evaluation of insurance policies in the Saudi Arabian construction contracts.

The construction sector is more complicated and prone to risk than many other industries due to the size of the projects and the financial capital involved. Arranging insurance is the prudent course of action for risk management in the construction sector. There is a lack of clarity in insurance policies for public construction projects in the Kingdom of Saudi Arabia (KSA), which poses additional risks to all involved contracting parties. The aim of this research is to evaluate insurance policies in the KSA's public construction projects to identify the key deficiencies and obstacles and provide a road map for improvement in the insurance sector concerning insurance against financial losses, professional liability, defects' liability, hidden defects, and others. Forty-two contractors and forty-two owners in Saudi Arabia were surveyed, using a questionnaire to gather information for the study about their knowledge of and attitudes regarding risk transfer through insurance (professional liability, defects liability, and hidden defects). The study also covers the selection criteria for insurance policies for projects that potentially shift risk to the construction sector. Ten criteria were also examined as potential sources of liability issues and suggested as potential remedies in KSA. The findings indicate that the duty and liability of engineers and those participating in these projects can be offset by engineers' insurance against professional errors and hidden flaws, and by the construction industry's clear liability policy. Additionally, the research is envisaged to contribute to construction projects' overall quality and safety, ensuring that robust legal and financial safeguards protect all stakeholders.

Bioequivalence trials for the approval of generic drugs in Saudi Arabia: a descriptive analysis of design aspects.

BACKGROUND: This retrospective analysis aimed to comprehensively review the design and regulatory aspects of bioequivalence trials submitted to the Saudi Food and Drug Authority (SFDA) since 2017. METHODS: This was a retrospective, comprehensive analysis study. The Data extracted from the SFDA bioequivalence assessment reports were analyzed for reviewing the overall design and regulatory aspects of the successful bioequivalence trials, exploring the impact of the coefficient of variation of within-subject variability (CVw) on some design aspects, and providing an in-depth assessment of bioequivalence trial submissions that were deemed insufficient in demonstrating bioequivalence. RESULTS: A total of 590 bioequivalence trials were included of which 521 demonstrated bioequivalence (440 single active pharmaceutical ingredients [APIs] and 81 fixed combinations). Most of the successful trials were for cardiovascular drugs (84 out of 521 [16.1%]), and the 2 × 2 crossover design was used in 455 (87.3%) trials. The sample size tended to increase with the increase in the CVw in trials of single APIs. Biopharmaceutics Classification System Class II and IV drugs accounted for the majority of highly variable drugs (58 out of 82 [70.7%]) in the study. Most of the 51 rejected trials were rejected due to concerns related to the study center (n = 21 [41.2%]). CONCLUSION: This comprehensive analysis provides valuable insights into the regulatory and design aspects of bioequivalence trials and can inform future research and assist in identifying opportunities for improvement in conducting bioequivalence trials in Saudi Arabia.

Eco-Innovative UHPC-Enhancing Sustainability, Workability, and Ductility with Recycled Glass Cullet Powder and Plastic Bottle Hybrid Fibers.

Utilizing waste materials in producing ultra-high-performance concrete (UHPC) represents a highly effective approach to creating environmentally sustainable concrete using renewable resources. This study focused on incorporating ground glass cullet (GP) at various replacement levels in UHPC production. Additionally, plastic bottle fibers (PBFs) were derived from discarded plastic bottles and employed in the mix. The replacement levels for GP spanned from 0% to 40%. Single-use plastic bottles were transformed into strip fibers, both with and without the inclusion of microsteel fibers, at varying contents of 1.1% and 2.2% (volume-based). A single-fiber test was conducted on PBFs under different strain rates. The introduction of optimal GP content had a profound positive iMPact on compressive strength. Incorporating 2.2% plastic strips induced strain hardening behavior, while further inclusion of microsteel fibers resulted in substantial enhancements in mechanical properties. Two types of microsteel fibers were employed, characterized by different aspect ratios of 65 and 100. The optimum GP content was identified as 10%. Moreover, the UHPC mix achieved superior compressive strength, exceeding 140 MPa when composed of 1.3% (volume-based) microsteel fibers with an aspect ratio of 65 and 2.2% PBF (volume-based). Notably, mixtures featuring microsteel fibers with a higher aspect ratio demonstrated the highest flexural strength, exceeding 8000 N in the presence of 2.2% PBF. Longer microsteel fibers exhibited adequate slip properties, facilitating strain transfer and achieving a strain-hardening response in conjunction with plastic bottle fibers. These findings illuminate the potential for harnessing hazardous waste materials to improve the performance and sustainability of UHPC formulations.

Evaluating the Clinical Effectiveness and Safety of Semaglutide in Individuals with Uncontrolled Type 2 Diabetes. Real-World Evidence from Saudi Arabia: The Observational, Multicenter, 15-Month EVOLUTION Study.

INTRODUCTION: This study aimed to assess the safety and effectiveness of semaglutide, administered either by weekly subcutaneous (SC) injection or orally, in real-life practice in Saudi Arabia in individuals with type 2 diabetes mellitus (T2DM). METHODS: A retrospective chart review study was conducted at 18 Saudi Arabia centers. An accredited centralized institutional review board approved the study. Medical records were included for individuals of any age ≥ 18 years with uncontrolled T2DM. The primary outcome measure was the laboratory glycated hemoglobin (HbA1c) level. Secondary measures included fasting blood glucose (FBG), weight, and hypoglycemia. All variables were checked after 6 and 12 months of semaglutide initiation. RESULTS: The analysis of this study included 1223 patients with uncontrolled T2DM (HbA1c > 7%). The mean (SD) baseline HbA1c was 10.02% (1.17). HbA1c was reduced by an average of 3.02% (0.84) and 3.17% (0.84) at 6 and 12 months, respectively. Results of a repeated measure analysis of variance (ANOVA) indicated significant differences in HbA1c (p value < 0.001). HbA1c levels at 6 and 12 months were significantly lower, 7.00% (0.70) and 6.85% (0.69), than at baseline, 10.02% (1.17). About 193 patients (56.4%) of the 295 patients having HbA1c < 9% achieved HbA1c of 5.7% or less. The frequency of hypoglycemia events was 4.60 (1.10) in the 3 months before semaglutide was initiated. The frequency of hypoglycemia events in the last 3 months was 2.30 (0.80) events and 0.80 (0.50) events at 6-month and 12-month follow-up visits, respectively. The percent reduction in body mass index (BMI) was an average of 13.07% (1.53) and 19.89% (4.07) at 6 and 12 months, respectively. Lipid profile and blood pressure were improved at 6 and 12 months. CONCLUSION: Semaglutide, administered either by SC injection or orally, provided substantial glycemic and weight-loss benefits in adults with T2DM.

Infective Endocarditis Caused By Streptococcus pluranimalium: A Case Report.

Infective endocarditis (IE) refers to an infection of the endocardium that can be caused by bacteria, viruses, or fungi. It can manifest either acutely or sub-acutely. Which can be complicated to stroke and congestive heart failure. We report a case of IE caused by Streptococcus (S.) pluranimalium. It is a rare organism that was discovered in 1999 in infections affecting domestic animals. It can cause serious complications, such as brain abscesses, and IE in both humans and animals. Our patient was diagnosed with IE caused by S. pluranimalium based on modified Duke's criteria. After the diagnosis was made, the patient started on intravenous antibiotics according to the blood cultures. Then, the patient significantly improved. We are reporting this case because only a few cases were documented for infective endocarditis caused by S. pluranimalium.

Flowability and Strength Characteristics of Binary Cementitious Systems Containing Silica Fume, Fly Ash, Metakaolin, and Glass Cullet Powder.

The present study examines the effects of supplementary cementitious materials (SCMs) on the flowability and strength development of binary mixes. This study was primarily motivated by the need to bridge the knowledge gap regarding paste and mortar mixes containing binary cement from a variety of performance perspectives. This study examined the flowability and strength development of binary mixes in their pastes and mortars when they contain various doses of silica fume (SF), fly ash (FA), metakaolin (MK), and glass cullet powder (GP) compared with the control mix. While the presence of SF and MK reduced workability because of the nature of their particles, the addition of FA and GP improved it to a certain extent because of the spherical and glassy nature of their particles, respectively. In addition, GP was used to compare its performance against SF, MK, and FA as an alternative cementitious material. In this study, the GP performed comparably to the other SCMs investigated and was found to be satisfactory. An investigation of the rheological properties, heat of hydration, thermal analysis, and pore systems of these mixes was conducted. Compared to the control mix, the presence of 5% GP improved the rheological properties and reduced the heat of hydration by 10%. The reduced workability in SF and MK mixes resulted in a lower content of pore water, while GP and FA incorporation enhanced it, owing to improved workability. The pore area is related to the pore water, which is directly related to improved workability. According to the following order, SF > MK > GP > FA, the strength was highest for mixes containing SF and MK, whereas, with GP and FA, there was a gradual reduction in the strength proportional to replacement level and improved workability. SF, GP, and FA can be identified as performance enhancers when formulating ternary and quaternary cementitious systems for low-carbon cement.

Awareness of healthcare providers on environment-friendly practices in operating rooms in selected hospitals in Riyadh, Saudi Arabia.

Climate change will have a great impact on humanity in upcoming years and will affect the health of all living creatures. Hospitals play a significant role in climate change due to their substantial waste production and they are considered a profound pollution source, with the Operating Theater as a main contributor. This study was aimed to examine the level of knowledge among healthcare professionals in Saudi Arabia concerning the proper implementation of operating room (OR) environmental procedures and efficient management of hospital waste. This is a cross sectional study performed across 3 hospitals in Riyadh, Saudi Arabia. The hospitals included are Prince Sultan military hospital, National guard hospital and King Salman hospital. The study included all the staff and health workers in OR (operating room), excluding all staff and health workers not in OR. The study took place between September 1 and November 1, 2022. None of the study participants mentioned that their institute or hospital fully engaged in Greenhealth Greening the OR initiative. Almost 1 to 3rd of the study participants (38.1%) mentioned that endorsement and participation in the practice of Greenhealth Greening the OR initiative was not implemented at all, and 45% of the participants were completely unaware of such an initiative. The study's findings suggest that healthcare providers in Saudi Arabia are not fully aware of environmentally friendly practices. Further, the current initiatives undertaken by the hospital administration fall short in attaining environmentally sustainable benchmarks.

A Neurophysiological Evaluation of Cognitive Load during Augmented Reality Interactions in Various Industrial Maintenance and Assembly Tasks.

Augmented reality (AR) has been shown to improve productivity in industry, but its adverse effects (e.g., headaches, eye strain, nausea, and mental workload) on users warrant further investigation. The objective of this study is to investigate the effects of different instruction methods (i.e., HoloLens AR-based and paper-based instructions) and task complexity (low and high-demanding tasks) on cognitive workloads and performance. Twenty-eight healthy males with a mean age of 32.12 (SD 2.45) years were recruited in this study and were randomly divided into two groups. The first group performed the experiment using AR-based instruction, and the second group used paper-based instruction. Performance was measured using total task time (TTT). The cognitive workload was measured using the power of electroencephalograph (EEG) features and the NASA task load index (NASA TLX). The results showed that using AR instructions resulted in a reduction in maintenance times and an increase in mental workload compared to paper instructions, particularly for the more demanding tasks. With AR instruction, 0.45% and 14.94% less time was spent on low- and high-demand tasks, respectively, as compared to paper instructions. According to the EEG features, employing AR to guide employees during highly demanding maintenance tasks increased information processing, which could be linked with an increased germane cognitive load. Increased germane cognitive load means participants can better facilitate long-term knowledge and skill acquisition. These results suggested that AR is superior and recommended for highly demanding maintenance tasks since it speeds up maintenance times and increases the possibility that information is stored in long-term memory and encrypted for recalls.

Clean Energy Based Multigeneration System for Sustainable Cities: Thermodynamic, and Stability Analyses.

This paper concerns the development and analysis of multigeneration systems based on hybrid sources such as biomass and wind. Industry requires different types of sources to provide several outputs, so the goal of this research was to fulfill the industrial requirement with optimization. The multigeneration cycle supplies enough power to satiate energy demands, i.e., power, cooling, hydrogen, air conditioning, freshwater, hot water, and heating. For this, the multigeneration cycle was modeled in the Engineering Equation Solver (EES) and Simulink to obtain optimized results for the industry. Energy and exergy for the multigeneration cycle were determined to assess the performance of the cycle and to investigate the optimized results for the overall system. This study shows that for configuration selection and design, different thermodynamic, economic, and environmental aspects should be considered. Based on the results, the selection of the best location for this multigeneration system was made. Power output from the wind turbine was around 7 MW and from biogas 0.6 MW. The overall exergy efficiency of the multigeneration system was found to be 0.1401.

GeNeo: A Bioinformatics Toolbox for Genomics-Guided Neoepitope Prediction.

High-throughput DNA and RNA sequencing are revolutionizing precision oncology, enabling personalized therapies such as cancer vaccines designed to target tumor-specific neoepitopes generated by somatic mutations expressed in cancer cells. Identification of these neoepitopes from next-generation sequencing data of clinical samples remains challenging and requires the use of complex bioinformatics pipelines. In this paper, we present GeNeo, a bioinformatics toolbox for genomics-guided neoepitope prediction. GeNeo includes a comprehensive set of tools for somatic variant calling and filtering, variant validation, and neoepitope prediction and filtering. For ease of use, GeNeo tools can be accessed via web-based interfaces deployed on a Galaxy portal publicly accessible at https://neo.engr.uconn.edu/. A virtual machine image for running GeNeo locally is also available to academic users upon request.

Omics in the Red Palm Weevil Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae): A Bridge to the Pest.

The red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Curculionidae), is the most devastating pest of palm trees worldwide. Mitigation of the economic and biodiversity impact it causes is an international priority that could be greatly aided by a better understanding of its biology and genetics. Despite its relevance, the biology of the RPW remains poorly understood, and research on management strategies often focuses on outdated empirical methods that produce sub-optimal results. With the development of omics approaches in genetic research, new avenues for pest control are becoming increasingly feasible. For example, genetic engineering approaches become available once a species's target genes are well characterized in terms of their sequence, but also population variability, epistatic interactions, and more. In the last few years alone, there have been major advances in omics studies of the RPW. Multiple draft genomes are currently available, along with short and long-read transcriptomes, and metagenomes, which have facilitated the identification of genes of interest to the RPW scientific community. This review describes omics approaches previously applied to RPW research, highlights findings that could be impactful for pest management, and emphasizes future opportunities and challenges in this area of research.

Pericardial Effusion as a First Manifestation of Rheumatoid Arthritis: A Case Report.

Rheumatoid arthritis (RA) is a systemic autoimmune disease that mainly affects the joints, which can lead to joint deformity. Since the disease is systemic, it affects many organs, including the heart, which can lead to pericarditis, coronary artery disease, and heart failure. We are reporting on a male patient, 34 years of age and Sudanese, who complained of shortness of breath and chest pain that started weeks before he came to the hospital, with no other associated symptoms. The patient was admitted to the hospital, and extensive work was done for the patient, which revealed that he had pericardial effusion secondary to RA, which is the first presentation of the disease. RA rarely presents as a first presentation with pericarditis and pericardial effusion. The patient was managed medically, and he showed significant improvement.

A Sustainable Alternative for Green Structural Lightweight Concrete: Performance Evaluation.

The use of structural lightweight concrete in the construction industry is on the rise in the last few decades mainly because of the higher strength per unit density, as it reduces the total deal load of the structural elements as compared with normal strength concrete. In addition, the environmental concerns of the concrete industry have gained supreme importance in recent times, demanding vital and effectual steps. In this regard, the current study was carried out to formulate an alternative approach for producing a sustainable lightweight structural concrete. The study followed two stages: initially, the selection of optimized manmade plastic aggregates based on trial concrete mixes, and finally, to gauge the physical-, mechanical- and durability related properties of the concretes integrating optimized manmade aggregate series at different replacement fractions. As a result of the first phase: two aggregate series out of eight were selected based on the compressive strength and durability properties of their concretes. In the next stage, all the properties for the optimized aggregate concrete were analyzed in terms of compressive strength. It was noted that the physical, mechanical and chloride penetration resistances have generally displayed a decreasing trend, with an increase in the manmade plastic aggregate replacement fractions as compared with reference lightweight concrete. However, the two aggregates, i.e., 70% DS-30% LLDPE and 50% QF-50% PET at the replacement fractions of 25% and 100%, were found to be the best two contenders that fulfilled the criteria for structural lightweight concrete, i.e., ASTMC330/C330M-14, and were proposed for structural lightweight purposes with low and relatively high strength and chloride resistance-based durability requirements, respectively. In addition, the brittleness ratios and structural efficiency parameters for the concretes of the 70% DS-30% LLDPE and 50% QF-50% PET also supplemented the aforementioned findings. Overall, this study presents a sustainable approach for the effective utilization of plastic waste for producing structural lightweight concrete.

Microsatellite Variation in the Most Devastating Beetle Pests (Coleoptera: Curculionidae) of Agricultural and Forest Crops.

Weevils, classified in the family Curculionidae (true weevils), constitute a group of phytophagous insects of which many species are considered significant pests of crops. Within this family, the red palm weevil (RPW), Rhynchophorus ferrugineus, has an integral role in destroying crops and has invaded all countries of the Middle East and many in North Africa, Southern Europe, Southeast Asia, Oceania, and the Caribbean Islands. Simple sequence repeats (SSRs), also termed microsatellites, have become the DNA marker technology most applied to study population structure, evolution, and genetic diversity. Although these markers have been widely examined in many mammalian and plant species, and draft genome assemblies are available for many species of true weevils, very little is yet known about SSRs in weevil genomes. Here we carried out a comparative analysis examining and comparing the relative abundance, relative density, and GC content of SSRs in previously sequenced draft genomes of nine true weevils, with an emphasis on R. ferrugineus. We also used Illumina paired-end sequencing to generate draft sequence for adult female RPW and characterized it in terms of perfect SSRs with 1-6 bp nucleotide motifs. Among weevil genomes, mono- to trinucleotide SSRs were the most frequent, and mono-, di-, and hexanucleotide SSRs exhibited the highest GC content. In these draft genomes, SSR number and genome size were significantly correlated. This work will aid our understanding of the genome architecture and evolution of Curculionidae weevils and facilitate exploring SSR molecular marker development in these species.

Health and Safety in Temporary Work Zone Road Construction Project in Saudi Arabia: Risks and Solutions.

Road project sites are dangerous and crash-prone, with many hazards that can cause injuries and can result in the deaths of road users or site-workers. Work zones for road construction or maintenance can potentially contribute to increasing these crashes. Many studies have addressed this issue; however, there is a lack of similar studies in Saudi Arabia. Therefore, this study contributes to developing safety practices for road work zones in Saudi Arabia by identifying, analyzing, and controlling the main risk factors. A survey approach was used to identify risk factors and potential countermeasures from road users' and civil engineering experts' perceptions. The main findings showed that most participants believed that the presence of work zones on the road might increase the probability of crash occurrence and that the highest risk factor that could cause a crash in a work zone is related to driver behavior. Both groups agreed that strict action against contractors or consultants who have safety violations would enhance road safety in work zones. Considering the findings of this study, decision-makers should take strong action to implement and improve road safety practices.

Transcriptomic Responses of Mycoplasma bovis Upon Treatments of trans-Cinnamaldehyde, Carvacrol, and Eugenol.

Mycoplasma bovis (M. bovis) is an insidious, wall-less primary bacterial pathogen that causes bovine pneumonia, mid-ear infection, mastitis, and arthritis. The economic losses caused by M. bovis due to culling, diminished milk production, and feed conversion are underestimated because of poor diagnosis/recognition. Treatment with common antibiotics targeting the cell wall is ineffective. Plant-derived antimicrobials (PDAs) such as food-grade trans-cinnamaldehyde (TC), eugenol (EU), and carvacrol (CAR) are inexpensive and generally regarded as safe for humans and animals yet possess strong anti-bacterial properties. In preliminary studies, we found that all three PDAs inhibited the growth of M. bovis in vitro. Through RNA sequencing, we report here that CAR affected the expression of 153 genes which included the downregulation of energy generation-related proteins, pentose phosphate pathway, and upregulation of ribosomes and translation-related proteins. Few differentially expressed genes were found when M. bovis was treated with TC, EU, or when the three PDAs were double or triple combined. Our results suggest that, as opposed to the effect of CAR, the growth-inhibitory effects of TC and EU at levels tested may be exerted through mechanisms other than gene expression regulations.

State of the Art of BIM Integration with Sensing Technologies in Construction Progress Monitoring.

The necessity for automatic monitoring tools led to using 3D sensing technologies to collect accurate and precise data onsite to create an as-built model. This as-built model can be integrated with a BIM-based planned model to check the project's status based on algorithms. This article investigates the construction progress monitoring (CPM) domain, including knowledge gaps and future research direction. Synthesis literature was conducted on 3D sensing technologies in CPM depending on crucial factors, including the scanning environment, assessment level, and object recognition indicators' performance. The scanning environment is important to determine the volume of data acquired and the applications conducted in the environment. The level of assessment between as-planned and as-built models is another crucial factor that could precisely help define the knowledge gaps in this domain. The performance of object recognition indicators is an essential factor in determining the quality of studies. Qualitative and statistical analyses for the latest studies are then conducted. The qualitative analysis showed a shortage of articles performed on 5D assessment. Then, statistical analysis is conducted using a meta-analytic regression model to determine the development of the performance of object recognition indicators. The meta-analytic model presented a good sign that the performance of those indicators is effective where [p-value is = 0.0003 < 0.05]. The study is also envisaged to evaluate the collected studies in prioritizing future works from the limitations within these studies. Finally, this is the first study to address ranking studies of 3D sensing technologies in the CPM domain integrated with BIM.

Association of Chronic Kidney Disease With In-Hospital Outcomes of Endovascular Stroke Interventions.

BACKGROUND: Data on the differential impact of chronic kidney disease (CKD) on the outcomes of endovascular stroke interventions (ESI) for acute ischemic stroke (AIS) are limited. METHODS: Adult patients who underwent ESI for AIS between October 1st, 2015 and September 30th, 2019, were identified in a national multicenter database. The primary endpoints were in-hospital mortality and poor functional outcomes. Secondary endpoints included intracranial hemorrhage, mechanical ventilation, pneumonia, myocardial infarction, blood transfusion, length of stay, and cost. A multilevel mixed-effects regression model was used to derive adjusted outcomes. RESULTS: A total of 22,193 AIS patients who underwent ESI at 99 centers were included. Among those, 18,881 (85%) had no CKD, and 3312 (15%) had CKD. Patients with CKD were older and had a higher prevalence of key comorbidities. After multivariable risk adjustment, patients with CKD had significantly higher in-hospital mortality (Odds Ratio [OR] 1.55 [95% Confidence Interval] [CI] 1.40-1.73, p < 0.01), and poor functional outcomes (OR 1.38, 95%CI 1.26-1.50, p < 0.01). Major complications, including mechanical ventilation, pneumonia, blood transfusion, and myocardial infarction, were more common among CKD patients, who also had longer hospitalizations and accrued higher cost. CONCLUSION: The presence of CKD in patients with AIS treated with ESI is an independent predictor of in-hospital mortality and poor functional outcomes at discharge.

Differences in the Characteristics and Outcomes of Isolated Tricuspid and Mitral Valve Surgery for Valvular Regurgitation.

BACKGROUND: Isolated tricuspid valve (TV) surgery is associated with markedly worse outcomes than isolated mitral valve (MV) surgery. We hypothesized that this is related to late referral of patients with isolated TV disease. METHODS: Adult patients who underwent isolated TV or MV surgery in 2016-2017 were identified in the National-Readmission-Database. We compared the outcomes of isolated TV and MV surgery before and after adjustment for surrogates of late referral. RESULTS: A total of 21,446 patients who had isolated MV (n = 19,933), or TV surgery (n = 1153) were included. Patients in the TV group were younger (55.7 ± 16.6 vs. 63.4 ± 12.3 years), had lower socioeconomic status, but higher prevalence of surrogates for late referral [acute HF 41.0% vs. 22.0%, advanced liver disease 16.8% vs. 2.6%, non-elective surgery status 44.3% vs. 23.5%, need for peri-operative mechanical circulatory support 27.7% vs. 4.7%, and unplanned admissions in the 90 days before surgery 31.0% vs. 18.8%, (P < 0.001 for all)]. Surgery was performed on day 0/1 of the admission in 80% of patients in the MV group and 52% in the TV group, P < 0.001. Repair rate was 63.5% in the TV group and 56.3% in the MV group (P < 0.001). In-hospital mortality was 3-folds higher after TV surgery (8.7% vs. 2.5%; OR = 3.41, 95%CI 2.73-4.25, p < 0.001). However, this difference became non-significant after adjusting for baseline characteristics including surrogates for late referral (OR = 1.24, 95%CI 0.85-1.82, p = 0.27). CONCLUSION: The poor outcomes of isolated TV surgery compared with isolated MV surgery may be largely explained by the late referral for intervention in patients with isolated TR.