Faculty Bibliography

OBJECTIVE:To critically appraise the published comparative effectiveness studies on non-vitamin K antagonist oral anticoagulants (NOACs) in non-valvular atrial fibrillation (NVAF). Results were compared with expectations formulated on the basis of trial results with specific attention to the patient years in each study. METHODS:All studies that compared the effectiveness or safety between at least two NOACs in patients with NVAF were eligible. We performed a systematic literature review in Medline and EMbase to investigate the way comparisons between NOACs were made, search date 23 April 2019. Critical appraisal of the studies was done using among others ISPOR Good Research Practices for comparative effectiveness research. RESULTS:We included 39 studies in which direct comparison between at least two NOACs were made. Almost all studies concerned patient registries, pharmacy or prescription databases and/or health insurance database studies using a cohort design. Corrections for differences in patient characteristics was applied in all but two studies. Eighteen studies matched using propensity scores (PS), 8 studies weighted patients based on the inverse probability of treatment, 1 study used PS stratification and 10 studies applied a proportional hazards model. These studies have some important limitations regarding unmeasured confounders and channelling bias, even though the larger part of the studies were well conducted technically. On the basis of trial results, expected differences are small and a naïve analysis suggests trials with between 7200 and 56 500 patients are needed to confirm the observed differences in bleedings and between 51 800 and 7 994 300 to confirm differences in efficacy. DISCUSSION/CONCLUSIONS:Comparisons regarding effectiveness and safety between NOACs on the basis of observational data, even after correction for baseline characteristics, may not be reliable due to unmeasured confounders, channelling bias and insufficient sample size. These limitations should be kept in mind when results of these studies are used to decide on ranking NOAC treatment options.

We report a rare case of a 30-year-old female who had a long-standing history of middle aortic syndrome that was being managed nonsurgically. She presented with hypertension and buttock pain with plans to become pregnant. She underwent an aortoiliac bypass.

Hypogastric artery aneurysms (HAA) necessitate repair due to significant morbidity and potential mortality associated with rupture. Coverage or coiling of HAA are not always possible, as the risk of pelvic and spinal cord ischemia become especially significant in bilateral hypogastric disease as well as with prior extensive aortic coverage. We report 2 cases of endovascular HAA exclusion using parallel stent grafts for preservation of flow through the distal hypogastric artery branches and external iliac artery in patients with prior thoracic and abdominal aortic repairs, contralateral hypogastric disease, and significant anatomic constraints.

We report the case of a 55-year-old female who presented with symptomatic high-grade stenosis of the right internal carotid artery, years after her diagnosis of moyamoya disease (MMD), which had been treated with extensive carotid and cerebral vascular reconstructions. A percutaneous carotid revascularization was unsuccessful, and a carotid endarterectomy with bovine patch angioplasty was subsequently performed. The presence of symptomatic atherosclerotic carotid disease in combination with MMD, with all the perioperative challenges, has not been previously described.

OBJECTIVE:To determine the natural history of deep vein thrombosis in children presented with a first episode in the lower extremity veins. METHODS:Children with objective diagnosis of acute deep vein thrombosis were followed up with ultrasound and clinical examination. Risk factors and clinical presentation were prospectively collected. The prevalence of recurrent deep vein thrombosis and the development of signs and symptoms of chronic venous disease were recorded. RESULTS:There were 27 children, 15 males and 12 females, with acute deep vein thrombosis, with a mean age of 4 years, range 0.1-16 years. The median follow-up was 23 months, range 8-62 months. The location of thrombosis involved the iliac and common femoral vein in 18 patients and the femoral and popliteal veins in 9. Only one vein was affected in 7 children, two veins in 14 and more than two veins in 6. Recurrent deep vein thrombosis occurred in two patients, while no patient had a clinically significant pulmonary embolism. Signs and symptoms of chronic venous disease were present at last follow-up in 11 patients. There were nine patients with vein collaterals, but no patient developed varicose veins. Reflux was found in 18 veins of 11 patients. Failure of recanalization was seen in 7 patients and partial recanalization in 11. Iliofemoral thrombosis (p = 0.012) and failure to recanalize (p = 0.036) increased significantly the risk for developing signs and symptoms. CONCLUSIONS:Children with acute proximal deep vein thrombosis develop mild chronic venous disease signs and symptoms at mid-term follow-up and are closely related with iliofemoral thrombosis and failure to recanalization.

Anomalies in the course and drainage of the Inferior Vena Cava (IVC) may complicate normal functioning, correct diagnosis, and therapeutic interventions within the abdomen. Development of the IVC occurs during the 4th to 8th week of gestation, and due to its developmental complexity, there are many opportunities for malformations to occur. Although most IVC anomalies are clinically silent and are usually discovered incidentally on abdominal imaging, aberrations may be responsible for formation of thrombosis, back pain, and anomalous circulation of blood to the heart. In this review, we will discuss the most common variations and abnormalities of the IVC, which include the posterior cardinal veins, the subcardinal veins, the supracardinal veins, persistent left IVC, IVC duplication, situs inversus, left retroaortic renal vein, left circumaortic renal collar, scimitar syndrome, and IVC agenesis. For each abnormality outlined above, we aim to discuss relevant embryology and potential clinical significance with regards to presentation, diagnosis, and treatment as is important for radiologists, surgeons, and clinicians in current clinical practice.

BACKGROUND:Pelvic congestion syndrome (PCS) imaging workup algorithms are not well-defined. The purpose of our study is to gauge the impact and accuracy of duplex ultrasound (DU) to assist in the diagnosis of PCS. METHODS:We reviewed the records of 48 patients with PCS seen at a vein center from June 2010 to June 2012. All patients had DU plus either computed tomography venography (CTV) or conventional venography (CV). Measurements of the left (LOV) and right ovarian vein (ROV) diameter and the presence or absence of ovarian vein reflux were obtained using DU and compared with either CTV or CV to assess sensitivity and specificity. An ovarian vein diameter >6 mm was considered abnormal. RESULTS:All patients were female (29 Caucasians, 18 Hispanic, and 1 Asian). The mean number of pregnancies was 3 (range, 1-5). All patients had lower extremity varicose veins, and 14 (29%) had vulvar varicosities. Thirty-four (71%) patients reported pelvic pain, 22 (46%) dyspareunia, 2 (4%) dysuria, and 1 (2%) hematuria. The median diameter of the LOVs and ROVs measured using DU compared with either CTV/CV were similar (DU, 8.6 and 5.6; CTV/CV, 8.3 and 6). The sensitivity and specificity of DU to demonstrate a dilated LOV were 100% and 57%, and for the ROV were 67% and 90%. Pelvic varicosities were identified in all but one patient with good correlation between DU and CV. CONCLUSIONS:DU has a high sensitivity to identify an abnormal LOV diameter that is greatly reduced when evaluating the ROV; however, the latter can be evaluated with another imaging modality such as CTV especially when DU results are equivocal or negative. A moderate specificity was found to determine both LOV and ROV abnormal diameters. All three imaging modalities are equally accurate to show the presence of pelvic varices.