Radiation Exposure in Endovascular Surgery According to Complexity: Protocol for a Prospective Observational Study.

In the past decades, we have witnessed tremendous developments in endovascular surgery. Nowadays, highly complex procedures are performed by minimally invasive means. A key point is equipment improvement. Modern C-arms provide advanced imaging capabilities, facilitating endovascular navigation with an adequate open surgical environment. Nevertheless, radiation exposure remains an issue of concern. This study aims to analyze radiation used during endovascular procedures according to complexity, comparing a mobile X-ray system with a hybrid room (fixed X-ray system). This is an observational and prospective study based on a cohort of non-randomized patients treated by endovascular procedures in a Vascular Surgery department using two imaging systems. The study is planned for a 3-year duration with a recruitment period of 30 months (beginning 20 July 2021) and a 1-month follow-up period for each patient. This is the first prospective study designed to describe the radiation dose according to the complexity of the procedure. Another strength of this study is that radiologic variables are obtained directly from the C-arm and no additional measurements are required for feasibility benefit. The results from this study will help us determine the level of radiation in different endovascular procedures, in view of their complexity.

Routinely ultrasound surveillance improves outcome after endovascular treatment of peripheral arterial disease: propensity-matched comparisons of clinical outcomes after ultrasound or clinical-hemodynamic based surveillance programs.

BACKGROUND: Endovascular treatment (EVT) has replaced open repair as the first option in intermittent claudication (IC) and chronic limb-threatening ischemia (CLTI) in several centers. However, evidence of the most optimal post-procedural surveillance strategy is sparse. This study aimed to compare two routine surveillance programs after EVT of IC/CLTI: clinical and hemodynamic assessment (CHA) vs. duplex ultrasound (DUS) and clinical/hemodynamic assessment in combination. METHODS: Between February 2012 and December 2015, all patients with EVT of IC/CLTI were allocated to either CHA or DUS-based routine surveillance programs. The allocation-ratio was 1:2 (CHA:DUS), and propensity score matching (PSM) was used to control baseline differences between the groups. Follow-up visits in the CHA group consisted of clinical assessment and ABI at 3, 6, 12 and 24 months. Follow-up visits in DUS group consisted of clinical assessment, ABI, and target vessel DUS at 1, 3, 6, 12, 18 and 24 months. RESULTS: In total, 340 legs in 305 patients suffering from IC/CLTI were included; 111 (33%) in the CHA-group and 229 (67%) in the DUS group. The two groups were identical except for a significantly lower incidence of diabetes mellitus in the CHA group than the DUS group, 55% vs. 72%, respectively (P=006). Based on PSM, the CHA-group vs. the DUS-group was burdened of an increased risk of amputation (12.5% vs. 8.27%, HR=0.41 [95% CI: 0.17-0.96]), and a higher mortality (21.2% vs. 12.8%, HR=0.37 [95% CI: 0.19-0.72]). The reported differences in reintervention rate (7.5% vs. 12.8%, HR=1.12 [95% CI: 0.44-2.84]) were insignificant. The mean follow-up was 317 days (SD=0.214) in the CHA group and 611 days (SD=0.298) in the DUS group. CONCLUSIONS: Our results suggest that DUS-based routine surveillance after EVT of IC/CLTI is superior to CHA-based routine surveillance in improved amputation rate and mortality.

Usefulness of ultrasound-guided tibio-pedal access in patients with critical limb ischemia.

INTRODUCTION: Retrograde access performed guided by fluoroscopy or ultrasound. We aimed to analyze the usefulness of ultrasound in retrograde access in patients with critical limb ischemia. METHODS: Observational analytical study. From December 2013 to June 2019. We included all retrograde accesses that were guided by ultrasound. Our register assesses demographic and clinical data, the vessel used as retrograde access, the procedure performed, the amount of contrast agent used and time of fluoroscopy, access failure, and local complications. RESULTS: On 715 procedures performed, was used ultrasound-guided retrograde access in 25 patients (64% men). The mean age was 74.8 years (45-90), with 92% of diabetics and 32% of chronic renal failure. Two patients with Rutherford stage 4 and 23 with stage 5-6. In 24 (96%) patients the ultrasound-guided puncture was successful, while in one (4%) of them, it was not possible to enter the target vessel. After the punch, was achieved the technical success of revascularization in 19 (79.2%) patients, with 5 (20.8%) in whom did not the arterial injury was not overcome. The arteries used as retrograde access were: anterior tibial 11, posterior tibial 10, and peroneal in 4. The mean of contrast used was 63 mL (9-100 mL) with an average time of 43 min (15-76 min). Complications related did not observe in retrograde access. CONCLUSIONS: Ultrasound-guided retrograde distal access is an effective method that may use as a bailout method in those endovascular procedures in which it is not possible to cross the lesion anterogradely.

COVID-19 and aorto-enteric fistula.

We present the case of a 72-year-old male with upper gastrointestinal bleeding. He had been discharged from hospital two weeks before after severe COVID-19 infection, treated with lopinavir-ritonavir (L-R), hydroxychloroquine, tocilizumab, and methylprednisolone. On presentation, he was in hypovolemic shock. Esophagogastroduodenoscopy showed an ulcer in the third duodenal portion, which was sclerosed and hemodynamic stability was recovered. A scan was performed as it was in an atypical location for ulcers, showing an aortic aneurysm in close relationship to the duodenum, suggesting a primary aortoenteric fistula (PAEF).

Usefulness of ultrasound-guided tibio-pedal access in patients with critical limb ischemia. / Utilidad de la ecografía en la punción retrógrada distal en la isquemia crítica de extremidades inferiores.

INTRODUCTION: Retrograde access performed guided by fluoroscopy or ultrasound. We aimed to analyze the usefulness of ultrasound in retrograde access in patients with critical limb ischemia. METHODS: Observational analytical study. From December 2013 to June 2019. We included all retrograde accesses that were guided by ultrasound. Our register assesses demographic and clinical data, the vessel used as retrograde access, the procedure performed, the amount of contrast agent used and time of fluoroscopy, access failure, and local complications. RESULTS: On 715 procedures performed, was used ultrasound-guided retrograde access in 25 patients (64% men). The mean age was 74.8 years (45-90), with 92% of diabetics and 32% of chronic renal failure. Two patients with Rutherford stage 4 and 23 with stage 5-6. In 24 (96%) patients the ultrasound-guided puncture was successful, while in one (4%) of them, it was not possible to enter the target vessel. After the punch, was achieved the technical success of revascularization in 19 (79.2%) patients, with 5(20.8%) in whom did not the arterial injury was not overcome. The arteries used as retrograde access were: anterior tibial 11, posterior tibial 10, and peroneal in 4. The mean of contrast used was 63 mL (9-100 ml) with an average time of 43 minutes (15- 76 min). Complications related did not observe in retrograde access. CONCLUSIONS: Ultrasound- guided retrograde distal access is an effective method that may use as a bailout method in those endovascular procedures in which it is not possible to cross the lesion anterogradely.

Deep vein thrombosis in noncritically ill patients with coronavirus disease 2019 pneumonia: deep vein thrombosis in nonintensive care unit patients.

BACKGROUND: Venous thromboembolic events have been one of the main causes of mortality among hospitalized patients with coronavirus disease 2019 (COVID-19) pneumonia. The aim of our study was to describe the prevalence of deep vein thrombosis (DVT) in noncritically ill patients with COVID-19 pneumonia and correlate such observations with the thromboprophylaxis received. METHODS: We performed a prospective cohort study of 67 patients admitted to the hospital for COVID-19 pneumonia. The diagnosis was confirmed using polymerase chain reaction testing of nasopharyngeal specimens. The deep veins were examined using compression duplex ultrasonography with the transducer on B-mode. The patients were separated into two groups for statistical analysis: those receiving low-molecular-weight heparin prophylaxis and those receiving intermediate or complete anticoagulation treatment. Risk analysis and logistic regression were performed. RESULTS: Of the 67 patients, 57 were included in the present study after applying the inclusion and exclusion criteria; 49.1% were women, and the patient mean age was 71.3 years. All 57 patients had undergone compression duplex ultrasonography. Of these 57 patients, 6 were diagnosed with DVT, for an in-hospital rate of DVT in patients with COVID-19 pneumonia of 10.5%. All the patients who had presented with DVT had been receiving low-molecular-weight heparin prophylaxis. The patients receiving prophylactic anticoagulation treatment had a greater risk of DVT (16.21%; 95% confidence interval, 0.04-0.28; P = .056) compared with those receiving intermediate or complete anticoagulation treatment. We also found a protective factor for DVT in the intermediate or complete anticoagulation treatment group (odds ratio, 0.19; 95% confidence interval, 0.08-0.46; P < .05). CONCLUSIONS: Noncritically ill, hospitalized patients with COVID-19 pneumonia have a high risk of DVT despite receipt of correct, standard thromboprophylaxis.

Role of an age-adjusted D-dimer cutoff level in the diagnosis algorithm of lower limb deep venous thrombosis in outpatients.

OBJECTIVE: Our goal was to analyze the utility of the age-adjusted D-dimer cutoff value in patients with clinically suspected deep venous thrombosis (DVT) in an ambulatory care setting, including distal DVTs. METHODS: This was an observational cohort study of 606 outpatients older than 18 years presenting with low or moderate clinical suspicion of lower limb DVT (measured by Wells scale). D-dimer levels were obtained, and duplex ultrasound was performed (including femoropopliteal and below-knee veins). We calculated sensitivity, specificity, and positive and negative predictive D-dimer values and when to apply the age-adjusted D-dimer cutoff value (D-dimer threshold = age × 10 µg/L). We split patients older than 50 years into 10-year age groups. We constructed receiver operating characteristic curves of the D-dimer test for each group to find the best threshold (defined as the value of D-dimer that gives more specificity, maintaining the maximum possible sensitivity). RESULTS: There were 249 men and 357 women with a mean age of 69.3 years; 41 patients were diagnosed with DVT. At a D-dimer threshold of 250 µg/L, sensitivity was 93%, specificity was 8%, positive predictive value was 7%, and negative predictive value was 94%. When the age-adjusted cutoff level was applied, global sensitivity was 76% and specificity 61%; positive predictive value was 12%, and negative predictive value was 97%. False-negative rate was 24%. We split patients older than 50 years into 10-year age groups: 50 to 60 years, 60 to 70 years, 70 to 80 years, and >80 years. The optimum thresholds were, respectively, 526 µg/L, 442.5 µg/L, 475 µg/L, and 549. µg/L. CONCLUSIONS: In our series, the age-adjusted D-dimer cutoff level is not useful in the diagnostic algorithm of DVT.

Ultrasound Surveillance in Endovascular Revascularization of Lower Limbs.

BACKGROUND: Endovascular surgery has become the initial treatment for most patients with chronic ischemia of the lower limbs. Few studies support ultrasound surveillance (US) of this kind of procedures. The purpose of this study was to evaluate the initial efficacy of duplex ultrasound as a surveillance method in endovascular treatment in symptomatic peripheral arterial disease patients in our center. MATERIAL AND METHODS: A total of 113 endovascular procedures performed in 106 patients between February 2013 and June 2015 were included. Follow-up included clinical assessment, physical examination, ankle-brachial index (ABI), plethysmography, and ultrasound at 1, 3, 6, 12, 18, and 24 months after surgery. Patients without a minimum follow-up of two controls were excluded. Worsening was defined as follows: (1) in ultrasound, a restenosis >70%; (2) from ABI, a decrease >0.15; (3) clinically, a decrease in claudication distance, reappearance rest pain, or worsening injuries; (4) in plethysmography, flattening in the curve. RESULTS: The average age was 68.3 years, with 72% being men. Twenty-two percent of treated lesions were iliac, 57% were femoropopliteal, and 21% were distal. There were 329 visits, with a mean follow-up of 13.5 months (3-31). The US detected permeability or moderate stenosis in 66 patients (58.4%) and restenosis or occlusion in 47 (41.6%). When compared with clinical status, there was a noncorrelation in 23% and a discrepancy with respect to the ABI of 27% and of 39% with plethysmography. All these differences were statistically significant (P < 0.001). Twenty-one reinterventions were performed (18.6%), six patients died (5.3%), and 11 required major amputation (9.7%). CONCLUSIONS: Clinical status and hemodynamics can detect restenosis or occlusion of the procedure in a large part of the cases, but it can omit more than 20% of these that were only detected by US. The ultrasound follow-up is of great help to increase the reliability of the control in patients with endovascular revascularization of lower limbs.

Contrast-Induced Nephropathy: A Fact or Fiction in Lower Limb Revascularization?

INTRODUCTION: Contrast-induced nephropathy (CIN) is defined as an increase >25% of serum creatinine from baseline, occurring in 24-48 hours after exposure to contrast, while alternative explanations for renal impairment have been excluded. The volume administered directly relates to risk, increasing by 12% per 100 mL of contrast. According to the series, its incidence varies between 3.3% and 8% in patients without renal damage and 12-50% in patients with chronic kidney disease (CKD) and/or diabetes mellitus (DM). The purpose of this study is to determine the incidence of CIN in endovascular revascularization of lower limbs in our center, where we apply the ALARA concept (As Low As Reasonably Achievable) to the use of contrast. MATERIAL AND METHODS: 163 patients who underwent endovascular revascularization procedures in lower limbs were included in this prospective observational study between February 2013 and April 2015. They were classified according to clinical stage and presence of DM and/or CKD. Data included serum creatinine values preoperative and postoperative, type and volume of contrast used. Patients on hemodialysis and those without sufficient analytical data were excluded. Chi-squared test and Student t-test were used for data analysis. P < 0.05 was considered statistically significant. RESULTS: 109 patients were enrolled, with 67% of DM and 31.5% of CKD. CIN incidence was 3.7% in patients without DM neither CKD, in DM was 6.8% and 12.5% in CKD. Mean creatinine presurgery was 97.96 and postsurgery 97.07, finding no significant differences between them (P = 0.753). Medium-contrast volume was 37.43 mL ± 22.3. The worsening variable (creatinine postsurgery minus creatinine presurgery) was evaluated according to clinical stage, DM, or CKD, being not significant in either group. CONCLUSIONS: In our experience, the dose administered of contrast was not related to the existence of postprocedure CIN, due to the policy of optimizing the use of contrast.

[Long-term treatment with a low-molecular-weight heparin administered subcutaneously compared with a vitamin K antagonist: subanalysis of patients with cancer]. / Tratamiento a largo plazo con una heparina de bajo peso molecular subcutánea comparado con un antagonista de la vitamina K: subanálisis de pacientes con cáncer.

We performed a subanalysis of cancer patients enrolled in a clinical trial that compared long-term (6 months) treatment with a low-molecular-weight heparin (LMWH) administered subcutaneously or with acenocoumarol. The subanalysis assessed whether the characteristics of the tumor had an influence on the clinical response. A randomized open trial included 69 patients with cancer and symptomatic proximal deep vein thrombosis of the lower limbs. The tumor characteristics and treatment type were recorded. The main assessment criterion was the 12-month incidence of recurrent symptomatic venous thromboembolism (VTE). Sixty-one patients (88.4%) were analyzed. At the time of inclusion, the cancer characteristics and treatment were comparable between the 2 groups. Over the course of 12 months, the recurrent VTE was significantly greater in the elderly patients (71.5 ± 6.4 vs. 62.0 ± 15.1; p=.006). The logistic regression analysis showed no association between VTE recurrence and the location or extent of the tumor. However, the use of thrombogenic chemotherapy (p=.045) was independently associated with VTE recurrence, and longterm treatment with tinzaparin was almost a protective factor (p=.15). In this small sample, we observed an association between thrombogenic chemotherapy and recurrent VTE. The tendency towards a reduction in VTE recurrence at 12 months in patients with cancer in the LMWH group could be attributed to the effect of the full LMWH dosage.

The role of color duplex sonography in the diagnosis of giant cell arteritis.

OBJECTIVE: To determine the clinical usefulness of color duplex sonography in the diagnosis of giant cell arteritis as an alternative to temporal artery biopsy. METHODS: From May 1998 to November 2002, 68 consecutive patients seen in our hospital with a clinical suggestion of active temporal arteritis were included. Forty-eight patients were female and 20 were male, with a mean age of 77 years. Color duplex sonography with a linear array transducer (5-10 MHz) was used to assess temporal artery morphologic characteristics before a biopsy was performed. The main sonographic criterion for a positive diagnosis was visualization of a hypoechoic halo around the temporal artery. These data were compared with pathologic findings. The kappa statistic was used to determine the level of agreement. Sensitivity, specificity, positive and negative predictive values, and accuracy of duplex sonography as a diagnostic test were assessed. RESULTS: The color duplex sonographic findings were positive in 25 of 68 patients with a clinical suggestion of giant cell arteritis. The diagnosis was confirmed by biopsy in 22 patients; there were 4 false-positive results and 1 false-negative result by duplex sonography. The kappa value was 0.84. Sensitivity, specificity, positive and negative predictive values, and accuracy for duplex sonography were 95.4%, 91.3%, 84%, 97.6%, and 92.6%, respectively. CONCLUSIONS: The use of high-resolution color duplex sonography may replace biopsy in the diagnosis of giant cell arteritis.