Analysis of Aortic Arch Hemodynamics With Simulated Bird's Beak Effects.

OBJECTIVE: The objective of this study was to investigate the flow effects in different degrees of thoracic aortic stent graft protrusion extension by creating bird beak effect simulations using accurate 3D geometry and a realistic, nonlinear, elastic biomechanical model using computer-aided software SolidWorks. METHODS: Segmentation in 3D of an aortic arch from a computed tomography (CT) scan of a real-life patient was performed using SolidWorks. A parametric analysis of three models was performed: (A) Aortic arch with no stent, (B) 3 mm bird-beak configuration, and (C) 6.5 mm bird-beak configuration. Flow velocity, pressure, vorticity, wall shear stress (WSS), and time average WSS were assessed. RESULTS: The flow velocity in Model A remained relatively constant and low in the area of the ostium of the brachiocephalic artery and doubled in the left subclavian artery. On the contrary, Models B and C showed a decrease in velocity of 52.3 % in the left subclavian artery. Furthermore, Model B showed a drop in velocity of 82.7% below the bird-beak area, whereas Model C showed a decline of 80.9% in this area. The pressure inside the supra-aortic branches was higher in Model B and C compared with Model A. In Model A, vorticity only appeared at the level of the descending aorta, with low to non-vorticity in the aortic arch. In contrast, Models B and C had an average vorticity of 241.4 Hz within the bird beak area. Regarding WSS, Model A, and Model B shared similar WSS in the peak systolic phase, in the aortic arch, and the bird beak area, whereas Model C had an increased WSS by 5 Pa on average at these zones. CONCLUSION: In the present simulations' lower velocities, higher pressures, vortices, and WSS were observed around the bird beak zone, the aortic arch, and the supra-aortic vessels.

Where does Hispanic Latin America stand in biomedical and life sciences literature production compared with other countries?

Objectives: to provide objective quantitative data about medical-related scientific production in Hispanic Latin America compared to different regions and identify demographic and political variables that could improve research. Study design: This is an analytical, observational, cross-section bibliometric study about all fields of medical-related scientific production over five years in different regions and its relationship with demographic and political variables that could impact research and the health system quality. Methods: Data on the total scientific production of all Hispanic Latin American countries and other countries representing almost 90% of mundial publications between 2017 and 2021 were retrieved from the PubMed database. Demographic and political data were obtained from open online databases. Counts of publications were rationed to population and analyzed with all other demographic, region, and language variables, using univariate Poisson regression and negative binomial regression (for over-disperse variables) analysis. Multivariate negative binomial regression was used to analyze the combined effect of variables related to the healthcare and research Sectors. Results: Hispanic Latin America increased yearly from 29,445 publications in 2017 to 47,053 in 2021. This cumulative growth of almost 60% exceeded the 36% increment in all countries' publications and was only below that of Russia and China, which grew 92% and 87%, respectively. Negative binomial regression showed that the percentage of gross income dedicated to research (IRR 2.036, 95% CI: 1.624, 2.553, p< .001), life expectancy at birth (IRR 1.444, 95% CI: 1.338, 1.558, p< .001), and the number of medical doctors per inhabitant (IRR 1.581, 95% CI: 1.17, 2.13, p = .003) positively impacted scientific production. A higher mortality associated with chronic diseases between ages 30 and 70 (IRR 0.782, 95% CI: 0.743 0.822, p< .001) and a lower population with access to medicine (IRR 0.960, 95% CI: 0.933, 0.967, p< .001) were found to impact scientific production negatively. Hispanic Latin American countries published less than 20% of those with English as their native language (p< .001). Conclusion: Hispanic Latin America has increased the gross number of publications by almost 60 % from 2017 to 2021. However, the number of publications per 100,000 inhabitants is still low compared to other countries. Our analysis highlights that this may be related to lower GDP, research investment, and less healthcare system quality.

Stereolithographic (SLA) 3D Printing for Preprocedural Planning in Endovascular Aortic Repair of a Thoracic Aneurysm.

BACKGROUND: When treating aortic aneurysm patients with complex anatomical features, preprocedural planning aided by 3D-printed models offers valuable insights for endovascular intervention. This study highlights the use of stereolithographic (SLA) 3D printing to fabricate a phantom of a challenging aortic arch aneurysm with a complex neck anatomy. CLINICAL CASE: A 75-year-old female presented with a 58 mm descending thoracic aortic aneurysm (TAA) extending to the distal arch, involving the left subclavian artery (LSA) and the left common carotid artery (LCCA). The computed tomography (CT) scans underwent scrutiny by radiology and vascular teams. Nevertheless, the precise spatial relationships of the ostial origins proved to be challenging to ascertain. To address this, a patient-specific phantom of the aortic arch was fabricated utilizing an SLA printer and a biomedical resin. The thoracic endovascular aortic repair (TEVAR) procedure was simulated using fluoroscopy on the phantom to enhance procedural preparedness. Subsequently, the patient underwent a right carotid-left carotid bypass and a right carotid-left subclavian bypass. After a 24-hour interval, the patient underwent the TEVAR procedure, during which a 37 mm × 150 mm stent graft (CTAG, WL Gore and Associates, Flagstaff, AZ, USA) and a 40 mm × 200 mm stent graft (CTAG, WL Gore and Associates, Flagstaff, AZ, USA) were deployed, effectively covering the LSA and LCCA. Notably, the aneurysm exhibited complete sealing, with no indications of endoleaks or graft infoldings. At the 12-month follow-up, the patient remains in good health, with no evidence of endoleaks or any other surgery-related complication. CONCLUSION: This report showcases the successful use of a 3D-printed endovascular phantom in guiding the decision-making process during the preparation for a TEVAR procedure. The simulation played a pivotal role in selecting the appropriate stent graft, ensuring an intervention protocol optimized based on the patient-specific anatomy.

Fabrication of Soft Transparent Patient-Specific Vascular Models with Stereolithographic 3D printing and Thiol-Based Photopolymerizable Coatings.

An ideal vascular phantom should be anatomically accurate, have mechanical properties as close as possible to the tissue, and be sufficiently transparent for ease of visualization. However, materials that enable the convergence of these characteristics have remained elusive. The fabrication of patient-specific vascular phantoms with high anatomical fidelity, optical transparency, and mechanical properties close to those of vascular tissue is reported. These final properties are achieved by 3D printing patient-specific vascular models with commercial elastomeric acrylic-based resins before coating them with thiol-based photopolymerizable resins. Ternary thiol-ene-acrylate chemistry is found optimal. A PETMP/allyl glycerol ether (AGE)/polyethylene glycol diacrylate (PEGDA) coating with a 30/70% AGE/PEGDA ratio applied on a flexible resin yielded elastic modulus, UTS, and elongation of 3.41 MPa, 1.76 MPa, and 63.2%, respectively, in range with the human aortic wall. The PETMP/AGE/PEGDA coating doubled the optical transmission from 40% to 80%, approaching 88% of the benchmark silicone-based elastomer. Higher transparency correlates with a decrease in surface roughness from 2000 to 90 nm after coating. Coated 3D-printed anatomical replicas are showcased for pre-procedural planning and medical training with good radio-opacity and echogenicity. Thiol-click chemistry coatings, as a surface treatment for elastomeric stereolithographic 3D-printed objects, address inherent limitations of photopolymer-based additive manufacturing.

Latin America Research Output Within the Top 5 Vascular Surgery Journals.

BACKGROUND: Dedicated studies on patient outcomes are crucial to the development of effective policies aimed at prevention and management of vascular diseases. This study aims to determine the scientific productivity of Latin American countries through a bibliometric analysis of top 5 vascular journals. METHODS: The 5 dedicated vascular journals indexed in the "surgery" category were selected for analysis. These were the European Journal of Vascular and Endovascular Surgery (EJVES), the Journal of Vascular Surgery (JVS), the Journal of Endovascular Therapy (JEVT), the Journal of Vascular Surgery: Venous and Lymphatic Disorders (JVS-VL) and the Annals of Vascular Surgery (AVS). Databases were queried with the combination of each journal's name + each of the 21 Latin American countries. All possible combinations were searched. Inclusion criteria were articles affiliated with a university, medical center, or hospital from any Latin American country. RESULTS: A total of 501 articles were retrieved, 104 (20.7%) were published between 2000 and 2011, and 397 (79.2%) between 2012 and 2022. The journal with the most publications was AVS with 221 (43.9%), followed by JVS with 135 (26.9%), EJVES with 60 (11.9%), JEVT with 49 (9.9%), and JVS-VL with 36 (7.1%). Brazil had the highest volume of publications at 346 (69.0%), followed by Argentina at 54 (10.7%), Chile at 35 (6.9%), and Mexico at 32 (6.3%). JVS had a higher median citation when compared with AVS, JVS-VL, and JEVT, 18 vs. 5, 5.5, and 7, respectively (P = <0.001). Furthermore, JVS had a greater median citation than EJVES, at 18 vs. 12.5, respectively (P = 0.005). Median citation per year from 2000 to 2011 was 1.59 (range: 0-45), and 1.50 (range: 0-114.5) from 2012 to 2022 (P = 0.02). CONCLUSIONS: Latin America's research output within the vascular surgery field has increased over the years. Efforts must be made to increase research output in this region and translate findings into effective interventions for these populations.

Risk Factors, Clinical Presentation, Therapeutic Trends, and Outcomes in Arterial Thrombosis Complicating Unvaccinated COVID-19 Patients: A Systematic Review.

Data on characteristics and outcomes of coronavirus (COVID)-19 patients complicated with arterial thrombosis (AT) are scarce. Therefore, we carried out a systematic review (PRISMA, PROSPERO statements; PubMed, Scopus, and Web of Science) to identify risk factors, clinical presentation, treatment, and outcomes. We included publications from December 2019 to October 2020. Groups: (a) ischemic stroke, (b) thrombotic storm, (c) peripheral vascular thrombosis, (d) myocardial infarction, and (e) left cardiac thrombus or in-transit thrombus (venous system thrombus floating or attaching to the right heart). We considered 131 studies. The most frequent cardiovascular risk factors were: hypertension, diabetes, and dyslipidemia. A high proportion presented with asymptomatic, mild, or moderate COVID-19 (n = 91, 41.4%). We identified a high percentage of isolated ischemic stroke and thrombotic storm. Groups with higher mortality rate: intracardiac thrombus (1/2, 50.0%), thrombotic storm (18/49, 36.7%), and ischemic stroke (48/131, 36.6%). A small number received thromboprophylaxis. Most patients received antithrombotic treatment. The most frequent bleeding complication was intracranial hemorrhage, primarily with isolated stroke. Overall mortality was 33.6% (74/220). Despite a wide range of COVID-19 severity, a high proportion had AT as a complication of non-severe disease. AT can affect different vascular territories; mortality is associated with stroke, intensive care unit stay, and severe COVID-19.

Readmission After COVID-19 for Late Acute Venous Thrombosis; CASE SERIES and Systematic Review of the Literature.

OBJECTIVE: Assess heterogeneity within patients with resolved COVID-19 to broaden the vision about post-discharge thrombotic cases and postulate possible related mechanisms in search of better anticoagulation guidelines. This study details patients' characteristics, medical history, treatment, and outcomes of readmitted patients with late acute thrombosis through a systematic review of the literature and patients from our academic center database. METHODS: We extracted the records of patients readmitted for venous thrombosis complications after discharge from the database of the first 2000 patients admitted with COVID-19 in our academic center; we also performed a systematic review of the literature using the Medical Subject Headings terms "late thrombosis," "COVID-19," + "venous thrombosis" in PubMed and Google Scholar according to PRISMA guideline. RESULTS: The literature review found 20 patients suitable for review matching the inclusion criteria. These patients were added to those in our database, summing up a total of 26 patients. The median age was 50 years old, 76.9% were male, and most were overweight or had grade 1 obesity (n = 11, 42.3%). None had a previous thrombotic history, but 50% had an underlying comorbidity. Thrombotic events presented on a median of 20 days (range: 4-150 days) from discharge. Pulmonary embolisms occurred in 23 patients (88.46%), deep vein thrombosis in 4, mesenteric thrombosis, and cerebral venous thrombosis in 1, respectively. CONCLUSION: This study found that most patients readmitted for thrombotic events after COVID-19 discharge were middle-aged men with Venous Thrombo Embolism events.

Biomechanical Profiling in Real-Life Abdominal Aortic Aneurysms in Different Clinical Scenarios.

BACKGROUND: The aim of this study was to demonstrate the biomechanical properties in different abdominal aortic aneurysm (AAA) presentations of real-life patients. We used the actual 3D geometry of the AAAs under analysis and a realistic, nonlinearly elastic biomechanical model. MATERIALS AND METHODS: Three patients with different clinical scenarios (R: rupture, S: symptomatic, and A: asymptomatic) with infrarenal aortic aneurysms were studied. Factors affecting aneurysm behavior such as morphology, wall shear stress (WSS), pressure, and velocities were studied and analyzed using steady state computer fluid dynamics using SolidWorks (Dassault Systems SolidWorksCorp., Waltham, Massachusetts). RESULTS: When analyzing the WSS, Patient R and Patient A had a decrease in the pressure in the bottom-back region compared with the body of the aneurysm. In contrast, WSS values appeared to be the most uniform across the entire aneurysm in Patient S. Furthermore, Patient A had focal small surface regions with high WSS values. The overall WSS in the unruptured aneurysms (Patient S and Patient A) were a lot higher than in the ruptured 1 (Patient R). All 3 patients showed a pressure gradient, being high at the top and low at the bottom. All patients had pressure values 20 times smaller in the iliac arteries compared with the neck of the aneurysm. The overall maximum pressure was similar between Patient R and Patient A, higher than the maximum pressure of Patient S. CONCLUSIONS: Computed fluid dynamics was implemented in anatomically accurate models of AAAs in different clinical scenarios for obtaining a broader understanding of the biomechanical properties that determine the behavior of AAA. Further analysis and the inclusion of new metrics and technological tools are needed to accurately determine the key factors that will compromise the integrity of the patient's aneurysms anatomy.

High Altitude Carotid Body Tumors Growth During active Surveillance.

BACKGROUND: The gold standard for patients with carotid body tumors (CBT) is surgical resection; nevertheless, some patients are unfit for surgery or, for other reasons, could not be operated on. Active surveillance has been known to be a reasonable strategy for these cases. This study aimed to evaluate tumor growth in unoperated patients with CBTs. METHODS: A retrospective review of all unoperated patients with CBT from a single academic hospital diagnosed between 2014 and 2021 was performed. Results of nonparametric testing were presented using the median and ranges for Mann-Whitney-U or Kruskal-Wallis. Significance was defined as a 2-tailed P < .05. RESULTS: The cohort included a total of 31 patients, with a median age of 60 years (range: 37-80 years), of which 27 (87.1%) were females. The patients live at a median altitude of 2800 meters (range: 2756-2980 meters) above sea level. Twenty (64.5%) patients had Shamblin I tumors, eight (25.8%) patients had Shamblin II tumors, and three (9.7%) patients had Shamblin III tumors. Median CBT volume at diagnosis was 14.1 cm3 (range: .9 - 213.3 cm3). Median volume at diagnosis of symptomatic tumors was substantially larger than asymptomatic tumors, 49.2 cm3 vs 7.9 cm3, respectively (P = .03). Median growth of the tumors during a median 15-month follow-up (range: 3-43 months) was 3.3 cm3 (range: 0-199.9 cm3). Overall, 77% (n = 24) of the CBTs grew at least 1 cm3. CONCLUSION: Most patients in the present study had tumor growth by at least 1 cm3, with a median tumor growth of 3.3 cm.3 In the present study tumor growth was shown to be greater than other low altitude CBT active surveillance studies; therefore, surgical resection should be recommended in patients with CBT living at high altitudes.

An analysis from the CAPACITY database of outcomes of preoperative embolization before carotid body tumor surgery compared with resection alone.

OBJECTIVE: There is no definitive consensus on the impact of preoperative embolization on carotid body tumor (CBT) treatment. The objective of this study was to compare surgical outcomes of patients who underwent preoperative embolization before CBT resection vs patients who underwent resection alone. METHODS: The CAPACITY registry included 1432 patients with CBT from 11 medical centers in four different countries. The group of patients undergoing CBT resection with preoperative embolization was matched in a 1:6 ratio from a pool of patients from the CAPACITY database, using a generated propensity score with patients who did not underwent preoperative embolization. RESULTS: A total of 553 patients were included for analysis. Mean patient age was 56.23 ± 12.22 years. Patients were mostly female (n = 469; 84.8%). Bilateral CBT was registered in 60 patients (10.8%). Seventy-nine patients (14.3%) underwent preoperative embolization. Embolized patients had larger CBT sizes than non-embolized patients (33.8 mm vs 18.4 mm; P = .0001). Operative blood loss was lower in the embolized group compared with the non-embolized group (200 mL vs 250 mL; P = .031). Hematomas were more frequent in the non-embolized group (0% vs 2.7%; P = .044). Operative time, rates of stroke, cranial nerve injuries, and death were not statistically significant between groups. CONCLUSIONS: Embolization before CBT resection was associated with significantly lower blood loss and lower neck hematomas than patients who underwent resection alone. Operative time, stroke, cranial nerve injuries, and death were similar between groups.

Risk Factors for Stroke After Carotid Paraganglioma Surgery.

BACKGROUND: The Carotid Paraganglioma Cooperative International Registry (CAPACITY) is an international registry composed of 1,432 patients with carotid body tumors (CBT) from 11 centers from 4 countries. The aim of this study was to identify risk factors for patients who presented stroke after carotid paraganglioma resection. METHODS: Clinical characteristics and demographics of patients who presented transoperatively and postoperatively stroke from the CAPACITY database were retrospectively gathered. Regression analysis was performed using single logistic regression with Omnibus' test for possible factors that might contribute to present stroke. RESULTS: Out of 1,432 patients, 8 (0.5%) female patients presented stroke. Median age was 53 years (range: 41-70 years). Six strokes occurred transoperatively, diagnosed clinically in the immediate postoperative period. Of them, none of the patients received any further treatment. Three of them died on postoperative day 2, 3, and 4. Two patients developed stroke during the first 24 postoperative hours, patients showed dysarthria, and aphasia. One of them was reintervened with thrombectomy due to thrombosis of the common carotid artery the other patient was treated conservatively. Median follow-up was 16 months (range: 2-72 months). Single logistic regression analysis revealed a history of diabetes mellitus (odds ratio (OR) 7.62), carotid artery disease (OR 17.51), and vascular lesion (OR 2.37) to have significantly increased odds of stroke during CBT surgery. CONCLUSIONS: In the present study history of diabetes mellitus, carotid artery disease, and vascular lesion had increased odds of stroke during CBT surgery. Findings are limited by low event rate and even larger cohorts are needed to fully define preventive preoperative strategies for preventing stroke.

Nasopharyngeal viral load at admission is not an independent predictor of thromboembolic complications in unvaccinated COVID-19 hospitalized patients.

COVID-19 patients may develop thrombotic complications, and data regarding an association between nasopharyngeal viral load and thrombosis is scarce. The aim of our study was to evaluate whether SARS-CoV-2 nasopharyngeal viral load upon admission is a useful prognostic marker for the development of thromboembolic events in patients hospitalized for SARS-CoV-2 infection. We performed a retrospective study of all hospitalized patients with a positive PCR test for SARS-CoV2 who had deep vein thrombosis (DVT), pulmonary embolization (PE), or arterial thrombosis diagnosed during their clinical course in a single academic center. The study population was divided according to the cycle threshold (Ct) value upon admission in patients with high viral load (Ct < 25), intermediate/medium viral load (Ct 25-30), and low viral load (Ct > 30). A regression model for propensity was performed matching in a 1:3 ratio those patients who had a thrombotic complication to those who did not. Among 2,000 hospitalized COVID-19 patients, 41 (2.0%) developed thrombotic complications. Of these, 21 (51.2%) were diagnosed with PE, eight (19.5%) were diagnosed with DVT, and 12 (29.2%) were diagnosed with arterial thrombosis. Thrombotic complications occurred as frequently among the nasopharyngeal viral load or severity stratification groups with no statistically significant differences. Univariate logistic regression revealed increased odds for thrombosis only in mechanically ventilated patients OR 3.10 [1.37, 7.03] (p = 0.007). Admission SARS-CoV-2 nasopharyngeal viral loads, as determined by Ct values, were not independently associated with thromboembolic complications among hospitalized patients with COVID-19.

Current trends in carotid body tumors: Comprehensive review.

BACKGROUND: Carotid body tumor (CBT) is a rare neoplasm that has been increasingly studied during the last decades; nevertheless, it continues to be a topic of controversy. This review aims to provide an update on the general features of CBT and particularly review different treatment strategies and primary outcomes. METHODS: Data for this literature review were identified by PubMed, Scopus, and Medline. 93 articles from the initial search were included, as well as 28 relevant studies utilizing the snowballing method; totaling 121 articles about CBT. RESULTS: Main features such as anatomy, embryology, genetics, clinical presentation, and diagnosis of CBT are presented, followed by evidence of different treatment strategies such as radiotherapy, preoperative embolization, vascular resection, and vascular reconstruction. Main complications are also discussed. CONCLUSION: This review summarizes the most critical aspects regarding CBT. Future studies should compare different treatments to attain the best surgical results with lower morbidity rates.

Clinical Characteristics and Surgical Outcomes of Carotid Body Tumors: Data from the Carotid Paraganglioma Cooperative International Registry (CAPACITY) Group.

BACKGROUND: This study's objective was to conduct a multinational registry of patients with carotid body tumors (CBTs) and to analyze patients' clinical characteristics, treatments, and outcomes. METHODS: Retrospective study from the Carotid Paraganglioma Cooperative International Registry involving eleven medical centers in Bolivia, Ecuador, Mexico, and Spain, of all patients with a CBT who underwent resection between 2009 and 2019. RESULTS: A total of 1432 patients with a CBT surgically treated were included. Median patient age was 54 years (range: 45-63 years), and 82.9% (1184) of the study cohort were female. While at low altitude, the proportion of female-to-male cases was 2:1, at high altitude, this proportion increased to 8:1, with statistically significant differences (p = .022). Median operative time was 139 min (range: 110-180 min), while median operative blood loss was 250 ml (range: 100-500 ml), with statistically significant difference in increased blood loss (p = .001) and operative time (p = .001) with a higher Shamblin classification. Eight (0.6%) patients suffered stroke. Univariate analysis analyzing for possible factors associated with increased odds of stroke revealed intraoperative vascular lesion to present an OR of 2.37 [CI 95%; 1.19-4.75] (p = 0.001). In 245 (17.1%), a cranial nerve injury was reported. Seven (0.5%) deaths were recorded. CONCLUSION: The most common CBT type on this cohort was hyperplasic, which might be partially explained by the high altitudes where these patients lived. Increased blood loss and operative time were associated with a higher Shamblin classification, and the risk of stroke was associated with patients presenting transoperative vascular lesions.

Gunshot Wounds Causing Distal Arterial Bullet Embolisms.

We report two cases involving small-caliber gunshot wounds to the chest with embolization of the bullet which complete occluding arterial circulation into the left lower extremity. A 30-years-old and 19-years-old men suffered gunshots wound to the thorax and abdomen with subsequent arterial embolisms into their left legs. Image studies revealed the left popliteal and femoral arteries occlusion by the missiles. Arteriotomies were auspiciously performed to retrieve the projectiles along with Fogarty catheters thrombectomies which conclude successful outcomes. At a 6 and 36 months' follow-up, the patients were doing well without any vascular associated complications. Bullet embolization of the arterial or venous systems is a rare complication of penetrating gunshot injuries with diagnostic and therapeutic challenges. This complication's suspicion should rise when there is a gunshot injury without an exit wound and with sudden pain or ischemia in an extremity. Individualized treatment should be urgently performed to avoid irreversible damage to the affected area.

Venous Thromboembolism in Hospitalized COVID-19 Patients Treated in a Single Academic Center in Mexico: A Case Series Study.

BACKGROUND: The increasing prevalence of venous thromboembolism (VTE) among patients with coronavirus disease 2019 (COVID-19) is a matter of concern as it contributes significantly to patients' morbidity and mortality. Data regarding the optimal anticoagulation regimen for VTE prevention and treatment remain scarce. This study describes the characteristics, treatment, and outcomes of COVID-19 patients with VTE treated in a single academic center in Mexico. METHODS: We conducted a retrospective study of all patients with a positive PCR test for SARS-CoV-2 hospitalized in a single academic center in Monterrey, Mexico, between March 2020 and February 2021, with a radiologically confirmed VTE, including deep venous thrombosis (DVT) and pulmonary embolism (PE). Informed consent was obtained from each patient before reviewing their medical records. RESULTS: Of the 2000 COVID-19 hospitalized patients, 36 (1.8%) developed VTE and were included in the analysis. The median age was 60 years (range 32-88 years), and up to 78% (n = 28) were males. Most patients (n = 34, 94%) had an underlying comorbidity and 47% (n = 17) had a BMI ≥ 30 kg/m2. In most cases (n=28, 78%), VTE presented as a PE, whereas the remaining 22% (n = 8) had a DVT. The median time between hospital admission and VTE was 8 days (range 0-33 days). Regarding the thromboprophylaxis regimen, 35/36 patients received low molecular weight heparin enoxaparin on admission, most commonly at a dose of 60 mg daily (n = 19, 53%). Other complications presented were superinfection (n = 19, 53%), acute kidney injury (n = 11, 31%), and septic shock (n = 5, 14%). A total of 69% of patients (n = 25) required intensive care unit admission, and patients' overall mortality was 55.6%. CONCLUSION: VTE remains a significant cause of increased morbidity and mortality among patients with COVID-19. The strikingly high mortality among patients with VTE highlights the need for further investigation regarding the best preventive, diagnostic, and treatment approaches.

Endovascular Treatment of Transplant Renal Artery Stenosis: A Systematic Review and Meta-analysis.

OBJECTIVE: Endovascular treatment through either percutaneous transluminal angioplasty (PTA) alone or stenting has been previously used as a treatment for transplant renal artery stenosis (TRAS). This review aimed to investigate the results of endovascular treatment for renal artery stenosis in transplanted kidneys as compared with the outcomes of interventions, medical management, and graft survival in non-TRAS patients. METHODS: A systematic review of PubMed, Google Scholar, Cochrane, and Scopus was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in which studies that reported outcomes of the treatment of TRAS via the endoluminal approach were identified, and their results were meta-analyzed. RESULTS: Fifty-four studies with a total of 1522 patients were included. A significant reduction of serum creatinine level was found, favoring the stenting group, with a mean difference of 0.68 mg/dL (95% confidence interval (CI), 0.17-1.19; Z=2.60, p=0.0009). Comparison of pre- and post-intervention values of any intervention revealed a significant decrease in overall serum creatinine level (0.65 mg/dL; 95% CI, 0.40-0.90; Z=5.09, p=0.00001), overall blood pressure, with a mean difference of 11.12 mmHg (95% CI, 7.29-14.95; Z=5.59, p=0.00001), mean difference in the use of medications (0.77; 95% CI, 0.29-1.24; p=0.002), and peak systolic velocity (190.05; 95% CI, 128.41-251.69; p<0.00001). The comparison of serum creatinine level between endovascular interventions and best medical therapy favored endovascular intervention, with a mean difference of 0.23 mg/dL (95% CI, 0.14-0.32; Z=5.07, p<0.00001). Graft survival was similar between the treated patients and those without TRAS (hazard ratio, 0.98; 95% CI, 0.75-1.28; p=0.091). The overall pooled success rate was 89%, and the overall complication rate was 10.4%, with the most prevalent complication being arterial dissection. CONCLUSION: The endovascular treatment of TRAS improves graft preservation and renal function and hemodynamic parameters. PTA + stenting appears to be a more effective option to PTA alone in the stabilization of renal function, with additional benefits from decreased restenosis rates. Further high-quality studies could expand on these findings.

Extensive deep vein thrombosis and pulmonary embolism as a unique clinical manifestation of COVID-19 in a young healthy patient.

BACKGROUND/OBJECTIVE: Deep vein thrombosis and pulmonary embolism have been described as complications in previously diagnosed COVID-19 patients, especially in those admitted in critical ill units, but, to our knowledge, there is no report of venous thromboembolism in an otherwise asymptomatic COVID-19 patient. METHODS: We report the case of a 22-year-old female, healthy patient with pulmonary embolism (Pulmonary Embolism Severity Index Score 22 points, low risk) and extensive proximal deep vein thrombosis as a unique clinical manifestation of the new coronavirus disease. RESULTS: The patient had no risk factors and no familial history of venous thromboembolism. All thrombophilia markers were negative. The patient was treated as first by an independent vascular team, performing vena cava filter placement and open thrombectomy. Her symptoms worsened, and after 3 weeks, she underwent US-enhanced thrombolysis and mechanical thrombectomy. She was isolated for 10 days and did not develop any other clinical manifestation of COVID-19 disease. During follow-up, she remained asymptomatic and complete patency of the venous system was achieved. Full oral anticoagulation was conducted for 6 months. CONCLUSION: COVID-19 appears to be a multi-symptomatic disease, and venous thromboembolism without any other previous described COVID-19 symptom could be considered one of its diverse clinical presentations and RT-PCR for SARS-CoV-2 tests emerge to be mandatory in patients with otherwise unexpected venous thrombosis.