Hospital Volume of Elective Abdominal Aortic Aneurysm Repair as a Predictor of Mortality After Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: Registry data suggest that centralising abdominal aortic aneurysm (AAA) surgery decreases the mortality rate after AAA repair. However, the impact of higher elective volumes on ruptured AAA (rAAA) repair associated mortality rates remains uncertain. This study aimed to examine associations between intact AAA (iAAA) repair volume and post-operative rAAA death. METHODS: Using data from official national registries between 2015 - 2019, all iAAA and rAAA repairs were separately analysed across 10 public hospitals. The following were assessed: 30 day and 12 month mortality rate following open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Associations between the 5 year hospital iAAA repair volumes (organised into tertiles) and rAAA associated mortality rate were analysed, regardless of treatment modality. Receiver operating characteristic (ROC) curves were generated to identify iAAA volume thresholds for decreasing the rAAA mortality rate. Subanalysis by treatment type was conducted. Threshold analysis was repeated with the Markov chain Monte Carlo (MCMC) procedure to confirm the findings. RESULTS: A total of 1 599 iAAAs (80.2% EVAR, 19.8% OSR) and 196 rAAAs (66.3% EVAR, 33.7% OSR) repairs were analysed. The median and interquartile range of the volume/hospital/year for all iAAA repairs were 39.2 (31.2, 47.4). The top volume iAAA tertile exhibited lower rAAA associated 30 day (odds ratio [OR] 0.374; p = .007) and 12 month (OR 0.264; p < .001) mortality rates. The ROC analysis revealed a threshold of 40 iAAA repairs/hospital/year (EVAR + OSR) for a reduced rAAA mortality rate. Middle volume hospitals for open iAAA repair had reduced 30 day (OR 0.267; p = .033) and 12 month (OR 0.223; p = .020) mortality rates, with a threshold of five OSR procedures/year. The MCMC procedure found similar thresholds. No significant association was found between elective EVAR volumes and ruptured EVAR mortality. CONCLUSION: Higher iAAA repair volumes correlated with a lower rAAA mortality rate, particularly for OSR. The recommended iAAA repair threshold is 40 procedures/year and five procedures/year for OSR. These findings support high elective volumes for improving the rAAA mortality rate, especially for OSR.

COVID-19 Infection in Critically Ill Patients Carries a High Risk of Venous Thrombo-embolism.

OBJECTIVE: The coronavirus disease of 2019 (COVID-19) due to SARS-CoV-2 infection has been found to cause an increased risk of venous thrombo-embolism (VTE). The aims of the study were to determine the frequency of VTE in critically ill patients with COVID-19 and its correlation with D dimer levels and pharmacological prophylaxis. METHODS: This was a cohort study of critically ill patients due to COVID-19. All patients admitted to the intensive care unit on the same day of April 2020 were selected, regardless of length of stay, and a single bilateral venous duplex ultrasound in the lower extremities was performed up to 72 hours later. Pulmonary embolism (PE) was diagnosed by computed tomography angiography. Asymptomatic and symptomatic VTE were registered, including pre-screening in hospital VTE. Characteristics of patients, blood test results, doses of thromboprophylaxis received, VTE events, and mortality after seven day follow up were recorded. RESULTS: A total of 230 critically ill patients were studied. The median intensive care unit stay of these patients was 12 days (interquartile range [IQR] 5 - 19 days). After seven days follow up, the frequency of patients with VTE, both symptomatic and asymptomatic, was 26.5% (95% confidence interval [CI] 21% - 32%) (69 events in 61 patients): 45 with DVT and 16 with PE (eight of them with concomitant DVT). The cumulative frequency of symptomatic VTE was 8.3% (95% CI 4.7% - 11.8%). D dimer values ≥ 1 500 ng/mL were diagnostic of VTE, with a sensitivity of 80% and a specificity of 42%. During follow up after screening, six patients developed new VTE. Three of them developed a recurrence after a DVT diagnosed at screening, despite receiving therapeutic doses of heparin. Mortality rates at seven day follow up were the same for those with (6.6%) and without (5.3%) VTE. CONCLUSION: Patients with severe COVID-19 infection are at high risk of VTE, and further new symptomatic VTE events and recurrence can occur despite anticoagulation. The prophylactic anticoagulant dose may need to be increased in patients with a low risk of bleeding.

Geometric, Biomechanic and Haemodynamic Aortic Abnormalities Assessed by 4D Flow Cardiovascular Magnetic Resonance in Patients Treated by TEVAR Following Blunt Traumatic Thoracic Aortic Injury.

OBJECTIVE: Thoracic endovascular aortic repair (TEVAR) is widely used for the treatment of patients with blunt traumatic thoracic aortic injury (BTAI). However, aortic haemodynamic and biomechanical implications of this intervention are poorly investigated. This study aimed to assess whether patients treated by TEVAR following BTAI have thoracic aortic abnormalities in geometry, stiffness, and haemodynamics. METHODS: Patients with BTAI treated by TEVAR at Vall d'Hebron Hospital between 1999 and 2019 were compared with propensity score matched healthy volunteers (HVs). All subjects underwent cardiovascular magnetic resonance (CMR) comprising a 4D flow CMR sequence. Spatially resolved aortic diameter, length, volume, and curvature were assessed. Pulse wave velocity, distensibility, and longitudinal strain (all measurements of aortic stiffness) were determined regionally. Moreover, advanced haemodynamic descriptors were quantified: systolic flow reversal ratio (SFRR), quantifying backward flow during systole, and in plane rotational flow (IRF), measuring in plane strength of helical flow. RESULTS: Twenty-six BTAI patients treated by TEVAR were included and matched with 26 HVs. They did not differ in terms of age, sex, and body surface area. Patients with TEVAR had a larger and longer ascending aorta (AAo) and marked abnormalities in local curvature. Aortic stiffness was greater in the aortic segments proximal and distal to TEVAR compared with controls. Moreover, TEVAR patients presented strongly altered flow dynamics compared with controls: a reduced IRF from the distal AAo to the proximal descending aorta and an increased SFRR in the whole thoracic aorta. These differences persisted adjusting for cardiovascular risk factors and were independent of time elapsed since TEVAR implantation. CONCLUSION: At long term follow up, previously healthy patients who underwent TEVAR implantation following BTAI had increased diameter, length and volume of the ascending aorta, and increased aortic stiffness and abnormal flow patterns in the whole thoracic aorta compared with matched controls. Further studies should address whether these alterations have clinical implications.

Long-Term Outcomes of Thoracic Endovascular Aortic Repair Focused on Bird Beak and Oversizing in Blunt Traumatic Thoracic Aortic Injury.

BACKGROUND: The acute aortic arch angle and narrow aortic diameter in young patients may lead to bird-beak configuration and excessive oversizing of the stent graft in thoracic endovascular aortic repair (TEVAR) for blunt traumatic thoracic aortic injury (BTTAI). Little is known about the association of these factors and complications in long-term follow-up. We evaluated the long-term outcomes in terms of complications, reinterventions, and survival, focusing on the effects of bird-beak configuration and oversizing. METHODS: This prospective cohort study included patients who underwent TEVAR for BTTAI in our department between October 1999 and January 2015. The main outcomes were migration, collapse, intragraft mural thrombus, reintervention, and survival and their association with oversizing and bird-beak configuration. RESULTS: Thirty-four patients were included. Median age was 36 years, and 21% were women. Mean graft oversizing was 19% (range: 8-27%) at the proximal end and 27% (range:, -20% to 50%) at the distal end. Mean follow-up was 98 months (12-198 months). Seven patients presented intragraft mural thrombus, one of whom developed an occlusive parietal thrombosis 1 year after the procedure. Four patients (9%) required reintervention: postoperative revascularization of the left subclavian artery in 2 cases and aortic reinterventions in 2 others. No migration or mortality was seen during follow-up. Bird-beak configuration was seen in 65%: the mean protrusion extension was 16 mm (standard deviation [SD]: 7.4 mm) and the mean angle was 51° (SD: 16°). The association between the complications and bird beak was not statistically significant. Patients with complications had significantly higher proximal end oversizing (23%) than the group with no complications (17%) (P = 0.0007). CONCLUSIONS: TEVAR for BTTAI shows good results in the long-term follow-up. Complications in our series seemed related to proximal end oversizing. Thoracic stent grafts with a smaller diameter should be available in all trauma centers to avoid excessive oversizing.

Impact of thoracic endovascular aortic repair following blunt traumatic thoracic aortic injury on blood pressure.

BACKGROUND: Blunt traumatic thoracic aortic injuries (BTAIs) are associated with a high mortality rate. Thoracic endovascular aortic repair (TEVAR) is the most frequently used surgical strategy in patients with BTAI, as it offers good short- and middle-term results. Previous studies have reported an abnormally high prevalence of hypertension (HT) in these patients. This work aimed to describe the long-term prevalence of HT and provide a comprehensive evaluation of the biomechanical, clinical, and functional factors involved in HT development. METHODS: Twenty-six patients treated with TEVAR following BTAI with no history of HT at the time of trauma were enrolled. They were matched with 37 healthy volunteers based on age, sex, and body surface area and underwent a comprehensive follow-up study, including cardiovascular magnetic resonance, 24-hour ambulatory blood pressure monitoring, and assessment of carotid-femoral pulse wave velocity (cfPWV, a measure of aortic stiffness) and flow-mediated vasodilation. RESULTS: The mean patient age was 43.5 ± 12.9 years, and the majority were male (23 of 26; 88.5%). At a mean of 120.2 ± 69.7 months after intervention, 17 patients (65%) presented with HT, 14 (54%) had abnormal nighttime blood pressure dipping, and 6 (23%) high cfPWV. New-onset HT was related to a more proximal TEVAR landing zone and greater distal oversizing. Abnormal nighttime blood pressure was related to high cfPWV, which in turn was associated with TEVAR length and premature arterial aging. CONCLUSIONS: HT frequently occurs otherwise healthy subjects undergoing TEVAR implantation after BTAI. TEVAR stiffness and length, the proximal landing zone, and distal oversizing are potentially modifiable surgical characteristics related to abnormal blood pressure.

The CHIVA strategy applied to large-diameter saphenous veins.

BACKGROUND: CHIVA (Cure Conservatrice et Hemodynamique de l'Insufficience Veineuse en Ambulatoire) is a conservative outpatient treatment strategy for chronic venous disease (CVD) that preserves the superficial venous system. A modified two-stage strategy is used in patients with a great saphenous vein (GSV) diameter ≥9 mm with the goal to decrease the risk of symptomatic superficial vein thrombosis (SVT), as the risk of complications is higher when first and second stage is performed simultaneously. METHODS: We conducted a retrospective observational study of 111 patients with CVD and a GVS diameter ≥9 mm treated with two possible stages of the CHIVA strategy, between January 2010 and December 2019. The goal of the first stage was to interrupt the main reflux escape point (incompetent saphenofemoral junction), thereby lowering the venous pressure and achieving a sufficient reduction in GSV diameter to enable, if necessary, a second stage that consists of disconnection of secondary reflux exit point (incompetent saphenous tributaries), with a lower risk of symptomatic SVT when patients do not show significant clinical improvement. Reductions in GSV diameter, postoperative complications and clinical improvement were analyzed. RESULTS: There were 60 men (54.1%) and 51 women (45.9%) with a mean age of 57±11.9 years. All patients undergone first surgical stage, and this interruption of the saphenofemoral junction was the single procedure in 77.5% of cases (86 patients). Mean follow-up time was 19.8 months. The second stage was performed in 25 patients (22.5%). Mean preoperative GSV diameter was 10.2±1.1 mm and this decreased to 7.1±1.5 mm after the first surgery (mean reduction, 3±1.5 mm, P<0.001). Six patients (5.4%) experienced recurrence due to recanalization of the reflux point and 16 patients (14.4%) developed SVT, which was symptomatic in 12 cases (10.8%). CONCLUSIONS: Interruption of the main reflux escape point as a single procedure in patients with a GSV diameter ≥9 mm led to a significant reduction in diameter and sufficient clinical improvement in almost 80% of cases.

Mortality and bleeding complications of COVID-19 critically ill patients with venous thromboembolism.

BACKGROUND: Venous thromboembolism (VTE) disease in COVID-19 patients is a remarkable issue, especially its relationship with bleeding events and mortality. The objective of this study was to describe the outcomes of critically ill patients with COVID-19, hospitalized in the Intensive Care Unit (ICU), in relationship with VTE during their stay. METHODS: This is a prospective cohort study of critically ill COVID-19 patients in two hospitals that underwent a venous ultrasound at the beginning of follow-up of both lower limbs in April 2020. In case of clinical suspicion of new VTE during the 30-day follow-up, additional ultrasound or thoracic CT were performed. Global VTE frequency, major bleeding events and survival were collected, and their predictors were studied. RESULTS: We included 230 patients. After 30 days of follow-up, there were 95 VTE events in 86 patients (37.4%). Thirteen patients (5.7%) developed major bleeding complications and 42 patients (18.3%) died. None of the comorbidities or previous treatments were related with bleeding events. D-Dimer at admission was significantly related with VTE development and mortality. Independent predictors of mortality in the regression model were older age (>66 years), D-Dimer at admission (>1.500 ng/mL) and low lymphocyte count (<0.45×109/L) with an AUC in the ROC curve of 0.81 (95% CI: 0.73-0.89). Patients presenting these three conditions presented a mortality of 100% in the predictive model. CONCLUSIONS: VTE frequency in ICU COVID-19 patients is high and risk of major bleeding is low. Comorbidities and laboratory parameters of admission in these patients can be a useful tool to predict mortality.