A case report: Retrograde arterial embolization of locally-injected SpaceOAR hydrogel material into the right common iliac artery bifurcation.

Biodegradable hydrogel-based matrices are becoming more widely utilized for a variety of medical applications, including SpaceOAR which is a hydrogel injected into the recto-prostatic space under ultrasound guidance to protect the rectum during prostate radiation therapy. Although a greater number of these procedures are being performed, there are no case reports on the potential complications which may result. In this report, we present the first case of retrograde embolization of SpaceOAR hydrogel into the right common iliac artery during routine office administration, as well as subsequent interventional angiography, inpatient and outpatient management, and clinical and imaging results at 1.5-month patient follow-up.

Percutaneous retrograde left external carotid artery coil embolization for management of hemorrhage from a persistent proatlantal intersegmental artery type 2.

Persistent fetal communications between the carotid and vertebrobasilar systems are rare and most often discovered incidentally. We present the case of a patient with oropharyngeal cancer status post chemotherapy, radiation therapy, and surgical resection who developed acute oropharyngeal hemorrhage on postoperative day 36, originating from branches of the ligated external carotid artery stump by retrograde flow through a proatlantal intersegmental artery type 2. This hemorrhage was successfully controlled with coil embolization through percutaneous access of the external carotid artery without recurrence at 1-year follow-up.

Risk of bleeding after ultrasound-guided jugular central venous catheter insertion in severely thrombocytopenic oncologic patients.

INTRODUCTION: We sought to assess the incidence and risk factors of bleeding after ultrasound-guided internal jugular (USGIJ) catheter insertion in severely thrombocytopenic cancer patients, as safe platelet (PLT) count threshold remains controversial. METHODS: Retrospective study of 52 patients with hematologic malignancies and severe thrombocytopenia who underwent USGIJ catheter insertion between 2014 and 2016. Group A included patients with prophylactic PLT transfusion and Group B without. Statistical analysis was performed. RESULTS: Group A included 28 patients and Group B 24. Baseline characteristics were equally distributed. Median catheter size was 12 Fr and tunneled in 20/52 patients. Median PLT count was not statistically different between the groups, before transfusion and after the procedure. Postoperative minor bleeding occurred in 10/52 patients, similar between groups. Lower PLT count, larger catheter caliber and trend for AML diagnosis were identified as risk factors for bleeding. Age, gender, BMI, renal dysfunction and tunneled insertion were not significant. CONCLUSION: Incidence of minor bleeding is low in severely thrombocytopenic patients after USGIJ catheter insertion. Prophylactic platelet transfusion may be reserved for patients with identified risk factors.

Repair of abdominal aortic aneurysms: preoperative imaging and evaluation.

Imaging is a critical component of the pre-procedure evaluation and planning of endovascular aneurysm repair (EVAR). Imaging is the mainstay for proper assessment of procedural candidacy, relevant vascular anatomy, device selection, and surgical approach. Computed tomography angiography (CTA) has long been considered the preferred modality for pre-operative imaging and evaluation prior to EVAR. Recently, advances in image quality and software technology have further enhanced the proceduralist's ability to plan and perform EVAR. In this review, we highlight the current state of the art to provide interventionalists a contemporary assessment of the available tools for pre-operative imaging and evaluation prior to EVAR.

Progression to stage 3 and 4 chronic kidney disease and risk factor stratification following endovascular aortic aneurysm repair.

BACKGROUND: Risk of progression to various stages of chronic kidney disease (CKD) after endovascular aortic aneurysm repair (EVAR) is unknown. This study estimates progression rates to stage 3 and 4 CKD after EVAR and identifies potential predictors for progression. METHODS: EVAR cases (2006-2012) were retrospectively reviewed. Freedom of progression to CKD was estimated using Kaplan-Meier analysis, and predictors for progression were identified using Cox proportional hazards model. RESULTS: Two hundred and twelve consecutive patients at a single academic institution underwent EVAR for infrarenal aneurysms. Estimated freedom from progression to stage 3 CKD was 80%, 76%, and 63% at 6, 12, and 18 months, respectively, and for stage 4, 97%, 96%, and 93% at 6, 12, and 18 months, respectively. Stage 3 CKD predictors of progression included age (odds ratio (OR): 1.106, p = 0.001), diabetes (OR: 3.052, p = 0.04), perioperative use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers (OR: 3.249, p = 0.02), and operative blood loss (OR: 1.002, p < 0.01). Stage 4 predictors included preoperative hemoglobin (OR: 0.473, p = 0.04) and baseline renal function (OR: 0.928, p = 0.001). Intraoperative contrast administration did not impact CKD development. CONCLUSIONS: Progression to stage 3 CKD after EVAR occurs more frequently and at a higher rate compared with progression to stage 4. Different risk factors are associated with progression to each of those stages of CKD.

Common carotid artery peak systolic velocity ratio predicts high-grade common carotid stenosis.

OBJECTIVE: Screening for common carotid artery (CCA) stenosis with duplex ultrasound (DUS) velocity criteria alone can be limited by within-patient and between-patients hemodynamic variability. This study aimed to evaluate inter-CCA velocity ratio criteria to predict high-grade CCA stenosis. METHODS: This was a retrospective review of consecutive patients who underwent computed tomography angiography and DUS peak systolic velocity (PSV) measurements of bilateral CCAs, independently recorded, between 2008 and 2014. Patients with dampened CCA waveforms on DUS composed group B. The remainder without dampened waveforms constituted group A. Inter-CCA PSV ratios were calculated by dividing the higher CCA PSV by the lower one of the other side, so the ratios would always be ≥1. Ratios were subsequently paired with each respective unilateral CCA diameter stenosis and differential bilateral CCA diameter stenosis. A quadratic regression model was fitted to predict unilateral and differential stenosis. Receiver operating characteristic curve was used to determine optimal ratios for ≥50% and ≥80% CCA stenosis. The study excluded patients with carotid artery occlusion. RESULTS: From a total of 201 patients, 193 patients were included in group A and 8 in group B. Within group A, 31 patients had ≥50% unilateral stenosis and 17 had ≥50% differential stenosis. All stenoses ≥50% were identified on the same side with the higher PSV. Inter-CCA PSV ratio predicted ≥50% unilateral (r(2) = 0.536; P < .001) and differential stenosis (r(2) = 0.581; P < .001). In group B, all patients had ≥60% stenosis that was near or involved the vessel origin. An increasing inter-CCA PSV ratio showed a trend toward contralateral high-grade stenosis (r(2) = 0.596; P = .1). Receiver operating characteristic curves showed an optimal threshold CCA ratio ≥2.16 for ≥50% unilateral stenosis with 92% accuracy, 62% sensitivity, and 98% specificity (area under curve = 0.854; 95% confidence interval, 0.759-0.948) and a ratio ≥2.62 for ≥50% differential stenosis with 97% accuracy, 83% sensitivity, and 98% specificity (area under curve = 0.94; 95% confidence interval, 0.835-1). CONCLUSIONS: DUS-based CCA PSV ratio can accurately predict unilateral and differential high-grade CCA stenosis. Also, in patients with unilateral dampened waveforms, it implied contralateral severe proximal stenosis. This parameter should be further validated in prospective studies and may serve as an adjunct screening tool to detect high-grade CCA stenosis.

Surgeon-modified fenestrated endograft to treat ruptured juxtarenal aneurysm.

IMPORTANCE: No endovascular devices are commercially available in the United States to treat high-surgical risk patients with aneurysms extending to visceral arteries. Treatment options are even further limited for symptomatic patients in need of urgent treatment. OBJECTIVE: To describe a successful urgent endovascular repair of a juxtarenal abdominal aortic aneurysm with contained rupture. DESIGN, SETTING, AND PARTICIPANTS: A hybrid suite using a surgeon-modified fenestrated endovascular graft and advanced 3-dimensional imaging workstation. The patient was an 82-year-old veteran taking clopidogrel and aspirin for coronary stents with significant cardiopulmonary comorbidities including multiple prior abdominal surgeries and a single functional left kidney. INTERVENTION: Surgeon-modified fenestrated endovascular aortic aneurysm repair. MAIN OUTCOMES AND MEASURES: Clinical, laboratory, and radiographic improvement. RESULTS: The patient was discharged 5 days after an uneventful postoperative course. On short-term follow-up, the patient had an early return to his baseline functional status. The excluded aneurysm sac shrank with patent visceral branches and there was an absence of endoleak on 3-month and 6-month surveillance computed tomography angiography. CONCLUSIONS AND RELEVANCE: Surgeon-modified fenestrated stent grafts may be a viable option for selected high-surgical risk patients with symptomatic complex abdominal aortic aneurysms.

Impact of intraoperative administration of local vancomycin on inguinal wound complications.

OBJECTIVE: Local vancomycin treatment has been shown to decrease sternal wound complication rates. Whether a similar effect can be achieved at other surgical sites is unknown. This study investigates the effect of local vancomycin on inguinal wound complication rates after vascular procedures. METHODS: Retrospective analysis was performed on 454 patients who underwent open aortofemoral or infrainguinal vascular procedures between 2006 and 2011. Patients received preoperative systemic antibiotics either alone (group A) or in conjunction with intraoperative wound application of vancomycin powder and irrigation (group B). Inguinal wound infection and dehiscence over a 30-day period were recorded. Fisher exact test and multivariate regression analyses were performed. RESULTS: There were 211 patients in group A and 243 patients in group B. Both groups had similar demographics and operative characteristics. There was a small but statistically significant decrease in the 30-day incidence of overall wound infections (25.1% vs 17.2%; P = .049) for group B patients. This was primarily due to a decreased rate in superficial infections (18.9% vs 11.5%; P = .033). No significant difference in the incidence of deep wound infections (6.1% vs 5.7%; P = .692) or overall dehiscence rates (22.2% vs 17.7%; P = .239) was detected. On multivariate analysis, history of chronic obstructive pulmonary disease and increased body mass index significantly increased risk of both infection and dehiscence. Medically optimized coronary artery disease was associated with less risk for dehiscence. CONCLUSIONS: Addition of intraoperative local vancomycin did not improve the rates of inguinal wound dehiscence or deep infections but had a positive impact on superficial wound infections.

Risk factors and impact of proximal fixation on acute and chronic renal dysfunction after endovascular aortic aneurysm repair using glomerular filtration rate criteria.

BACKGROUND: The incidence of renal impairment relevant to proximal fixation of aortic endograft devices remains unclear. METHODS: Retrospective cohort of 208 consecutive patients that underwent EVAR from 2006 to 2011. Estimated glomerular filtration rate (eGFR) was based on MDRD study equation. Acute kidney injury (AKI) and chronic kidney disease (CKD) were classified with ADIQ/RIFLE criteria and National Kidney Foundation criteria, respectively. Kaplan-Meier curve was applied to evaluate progression to CKD. Multivariate regression model was fit to identify predictors for developing AKI and CKD. RESULTS: Suprarenal fixation group (SF) included 110 patients and infrarenal fixation group (IF) included 98 patients. Both groups had similar demographics, baseline eGFR, and renal-protection protocols. There was a trend for decreased use of contrast in IF group (median: 93.5 vs. 103 cc, P = 0.07). AKI occurred in 15% of patients in SF group and 19% of patients in IF group (RR: 1.24, P = 0.47). The freedom from progression to stage 3 or 4 CKD in the SF group was 0.76, 0.72, and 0.49 at 6, 12, and 18 months, respectively, while for IF group was 0.8, 0.73, and 0.68, respectively (P = 0.4). Increasing age (P = 0.07), lengthy procedures (P < 0.001), and baseline renal dysfunction (P < 0.001) were significant predictors for developing CKD. Contrast volume (P < 0.001) and ace-inhibitors (P = 0.07) were predictors for AKI. CONCLUSION: Proximal fixation type has no significant effect on both acute and chronic renal function. Identification of modifiable perioperative risk factors may be used to improve renal function outcomes.

An update on endovascular management of acute thoracic aortic disease and future directions.

Thoracic endovascular aortic repair (TEVAR) has become an alternative treatment option for acute thoracic aortic disease. This review focuses on current endovascular treatment of acute thoracic aortic disease and future directions of TEVAR. TEVAR is a promising alternative approach to open surgery, with lower early mortality and morbidity rates, especially in high-risk cohorts. Furthermore, with accumulating experience and improving device technology and imaging modalities, TEVAR has become safer and has potential to expand treatment options to include ascending and arch pathologies.

Key role of alkaline phosphatase in the development of human-derived nanoparticles in vitro.

Alkaline phosphatase (ALP) is an enzyme critical for physiological and pathological biomineralization. Experiments were designed to determine whether ALP participates in the formation of calcifying nanometer sized particles (NPs) in vitro. Filtered homogenates of human calcified carotid artery, aorta and kidney stones were inoculated into cell culture medium containing 10% fetal bovine serum in the absence or presence of inhibitors of ALP or pyrophosphate. A calcific NP biofilm developed within 1 week after inoculation and their development was reduced by pyrophosphate and inhibitors of ALP. ALP protein and enzymatic activity were detected in washed NPs, whether calcified or decalcified. Therefore, ALP activity is required for the formation of calcifying NPs in vitro, as has previously been implicated during pathological calcification in vivo.

Technique of hybrid retrograde superior mesenteric artery stent placement for acute-on-chronic mesenteric ischemia.

Revascularization for acute mesenteric ischemia can be challenging in patients with bowel gangrene, peritoneal contamination, and no good source of inflow for a bypass graft. A 70-year-old female patient presented with acute-on-chronic mesenteric ischemia, flush superior mesenteric artery (SMA) occlusion, and diffuse aorto-iliac occlusive disease. This study describes the technique of hybrid retrograde SMA recanalization and stent placement using a midline laparotomy is described. The mid-portion of the SMA was exposed and jejunal branches were controlled with silastic vessel loop. Retrograde access was established under direct vision and the occluded SMA segment was crossed, pre-dilated, and stented using a balloon-expandable stent. The SMA was flushed through a longitudinal arteriotomy, which was closed using a saphenous vein patch. Retrograde hybrid SMA stenting is an expeditious option to revascularize patients with acute on chronic mesenteric ischemia who have peritoneal contamination and no other good source of inflow to the mesenteric arteries.

Incidence and risk factors of renal dysfunction after thoracic endovascular aortic repair.

OBJECTIVES: The risk of renal failure after thoracic endovascular aortic repair is not widely established. The aim of this study was to assess the incidence and risk factors of renal failure. METHODS: Between 1998 and 2008, 175 consecutive patients underwent 210 procedures at 2 tertiary academic institutions. Similar nephroprotective protocols and intravascular ultrasound were used. Retrospective analysis was performed. Generalized linear model was used to identify factors associated with change in postoperative estimated glomerular filtration rate. RESULTS: Underlying aortic diseases included 103 aneurysms, 72 dissections, 21 transections, and 14 penetrating ulcers. Median preoperative estimated glomerular filtration rate was 65 mL · min(-1) · 1.73 m(-2). Contrast media averaged 108.7 ± 69.8 mL. Median estimated glomerular filtration rates within 48 hours and 30 days were 69 and 67 mL · min(-1) · 1.73 m(-2), respectively. Rates of acute renal dysfunction risk (>25% estimated glomerular filtration rate decrease), acute kidney injury (>50% estimated glomerular filtration rate decrease), acute kidney function failure (>75% estimated glomerular filtration rate decrease), and hemodialysis were 9.8% (19/193), 1.6% (3/193), 0% (0/193), and 0.5% (1/193), respectively. Rates of renal dysfunction at 1 month and 6 months were 13.3% (10/75) and 17.7% (6/34), respectively. Risk factors for acute renal dysfunction were intraoperative hypotension, stroke, sepsis, lengthy procedures, and number of stents; at 1 and 6 months they were increased age, male gender, African American race, diabetes mellitus, chronic pulmonary disease, smoking, and zone 0 to 1 graft deployment. Obesity was nephroprotective. CONCLUSIONS: Thoracic aortic endograft has a significant rate of renal dysfunction; however, it is lower in this cohort than in previous smaller series. Routine use of intravascular ultrasound and reduced contrast may have contributed to lower rates of renal insufficiency.

Thrombus of the internal carotid artery: the contribution of computed tomographic angiography to clinical management.

Intraluminal thrombus adjunct to internal carotid artery plaque is a rare finding on traditional diagnostic imaging. Prompt diagnosis is important as it carries a high risk of recurrent stroke. We describe 2 symptomatic patients with severe stenosis on duplex scanning and internal carotid artery thrombus (ICAT) identified on subsequent computed tomographic angiography. Histology of the surgical specimen confirmed the composition predicted by computed tomography. Computed tomographic angiography can provide accurate diagnosis and characterization of internal carotid thrombus and lead to prompt therapeutic intervention.

Cerebral protection devices reduce periprocedural strokes during carotid angioplasty and stenting: a systematic review of the current literature.

PURPOSE: To compare through a systematic review of published literature the stroke outcomes in protected and unprotected carotid artery stenting (CAS). METHODS: PubMed and Cochrane electronic databases were queried to identify peer-reviewed publications from 1995 to 2007 meeting our pre-defined criteria for inclusion (English language, human only, at least 20 patients reported) and exclusion (procedures performed for the treatment of total occlusion, dissection, or aneurysmal disease; urgently performed procedures; use of covered stents; access other than transfemoral). Information was collected on a standardized data abstraction form for pooled analysis of total strokes within 30 days of procedure in all patients and in symptomatic and asymptomatic subgroups. A random effects meta-analysis of studies with concurrently reported data on protected and unprotected CAS was performed. RESULTS: Initial database query resulted in 2485 articles, of which 134 were included in the final analyses (12,263 protected CAS patients and 11,198 unprotected CAS patients). Twenty-four studies included data on both protected and unprotected CAS. Using pooled analysis of all 134 reports, the relative risk (RR) for stroke was 0.62 (95% CI 0.54 to 0.72) in favor of protected CAS. Subgroup analysis revealed a significant benefit for protected CAS in both symptomatic (RR 0.67; 95% CI 0.52 to 0.56) and asymptomatic (RR 0.61; 95% CI 0.41 to 0.90) patients (p<0.05). Meta-analysis of the 24 studies reporting data on both protected and unprotected stenting demonstrated a relative risk of 0.59 (95% CI 0.47 to 0.73) for stroke, again favoring protected CAS (p<0.001). CONCLUSION: Our systematic review indicated that the use of cerebral protection devices decreased the risk of perioperative stroke with CAS. A well designed randomized trial can further confirm our findings and possibly indicate the device with the best outcomes.

One patent intracranial collateral predicts tolerance of flow reversal during carotid angioplasty and stenting.

Internal carotid artery (ICA) flow reversal is an effective means of cerebral protection during carotid stenting. Its main limitation is that in the absence of adequate collateral flow it may not be tolerated by the patient. The purpose of this study was to determine if preoperative identification of intracranial collaterals with computerized tomographic (CTA) or magnetic resonance (MRA) angiography can predict adequate collateral flow and neurological tolerance of ICA flow reversal for embolic protection. This was a study of patients undergoing transcervical carotid angioplasty and stenting. Neuroprotection was established by ICA flow reversal. All patients underwent preoperative cervical and cerebral noninvasive angiography with CTA or MRA and had at least one patent intracranial collateral. Mean carotid artery back pressure was measured. Neurological changes during carotid clamping and flow reversal were continuously monitored with electroencephalography (EEG). Thirty-seven patients with at least one patent intracranial collateral on brain imaging with CTA or MRA were included. Mean carotid artery back pressure was 58 mm Hg. All procedures were technically successful. No EEG changes were present with common carotid artery occlusion and ICA flow reversal. One patent intracranial collateral provides sufficient cerebral perfusion to perform carotid occlusion and flow reversal with absence of EEG changes. Continued progress in noninvasive imaging modalities is becoming increasingly helpful in our understanding of cerebral physiology and selection of patients for invasive carotid procedures.