Percutaneous MR Imaging-Guided Laser Ablation for the Treatment of Symptomatic Cervicofacial Vascular Malformations.

PURPOSE: To evaluate the safety and effectiveness of percutaneous magnetic resonance (MR) imaging-guided laser ablation for the treatment of symptomatic soft tissue vascular malformations (VMs) in the face and neck. MATERIALS AND METHODS: An institutional review board-approved retrospective review was undertaken of all consecutive patients who underwent MR imaging-guided and monitored laser ablation for treatment of symptomatic, cervicofacial soft tissue VM. Preablation and postablation MR imaging findings were independently reviewed. Preablation and postablation VM sizes were documented. Preablation T2 signal characteristics and enhancement patterns as well as postablation change in both signal and enhancement were semiquantitatively assessed. Changes in VM size were compared using a paired t test. RESULTS: Thirteen patients (women, 9; age, 14.5-69.5 years) with 13 VMs were treated for moderate-to-severe pain (n = 4), swelling/mass effect (n = 8), or predominantly cosmesis (n = 1) with 22 total ablation sessions. The baseline maximum VM diameter was 5.7 cm ± 4.2. At baseline, all VMs (100%) demonstrated variable T2-weighted signal hyperintensity and enhancement. For painful VM, the baseline pain score was 8 ± 1. Clinical follow-up was available for 10 patients. Of patients with available follow-up, 3 (100%) treated for moderate-to-severe pain and 7 (100%) treated for swelling/mass effect reported subjective complete or partial symptomatic relief. The patient treated predominantly for cosmetic reasons was lost to follow-up. Two patients (15.4%) experienced minor adverse events by the Society of Interventional Radiology standards. There were no major adverse events. CONCLUSIONS: MR imaging-guided and monitored percutaneous laser ablation is safe and effective for the treatment of symptomatic, cervicofacial VMs.

Results of a Flexible Patient-Centered Approach to the Timing of Thoracic Outlet Decompression in Paget Schroetter Syndrome.

BACKGROUND: Treatment algorithms for subclavian vein (SCV) effort thrombosis (Paget-Schroetter syndrome- PSS) are multiple, ranging from thrombolysis (TL) with immediate or delayed thoracic outlet decompression (TOD) to conservative treatment with anticoagulation alone. We follow a regimen of TL/pharmacomechanical thrombectomy (PMT) followed by TOD with first rib resection, scalenectomy, venolysis, and selective venoplasty (open or endovascular) performed electively at a time convenient for the patient. Oral anticoagulants are prescribed for 3 months or longer based upon response. The aim of this study was to evaluate outcomes of this flexible protocol. METHODS: Clinical and procedural details of consecutive patients treated for PSS from January 2001 to August 2016 were retrospectively reviewed. Endpoints included success of TL and eventual clinical outcome. Patients were divided into 2 groups-Group I: TL/PMT + TOD; Group II: medical management/anticoagulation + TOD. RESULTS: PSS was diagnosed in 114 patients; 104 (62 female, mean age 31 years) who underwent TOD were included in the study. Group I: 53 patients underwent TOD after initial TL/PMT (23 at our institution and 30 elsewhere) with success (acute thrombus resolution) in 80% (n = 20) and 72% (n = 24) respectively. Adjunctive balloon-catheter venoplasty was performed in 67%. TL failed to recanalize the occluded SCV in 11% (n = 6). Complete thrombus resolution was seen in 9% (n = 5). Residual chronic thrombus in 79% (n = 42) resulted in median SCV stenosis of 50% (range 10% to 80%). With continued anticoagulation, further thrombus retraction was noted with median 40% improvement in stenosis including in veins with unsuccessful TL. TOD was performed at a median of 1.5 months (range 2-8 months). Rethrombosis of the SCV occurred in 3 patients 1-3 days postoperatively and was managed with MT/SCV stenting/balloon angioplasty and anticoagulation. Symptomatic relief was achieved in 49/53 (92%) patients at a median follow-up of 14 months. Group II: 51 patients underwent TOD following medical treatment elsewhere with anticoagulation alone for an average 6 months (range 2-18 months) with recurrent SCV thrombosis in 5 (11%). Thirty-nine patients (76%) had persistent symptoms; the remaining had asymptomatic compression of the SCV with maneuvers. SCV occlusion persisted in 4 patients (7%); the indication for TOD being residual symptoms from compression of collateral veins, the median residual stenosis was 70% (range 30-90%). TOD was performed at a median of 6 months after diagnosis of PSS. Open venous reconstruction with endovenectomy and patch was performed in 4 patients and stenting in 2. Symptomatic relief was achieved in 46/51 (90%) at a median follow-up of 24 months. CONCLUSIONS: For Paget Schroetter syndrome a management protocol encompassing elective thoracic outlet decompression at a convenient time following thrombolysis is safe and effective, with low risk of rethrombosis. Continued anticoagulation in the interim results in further recanalization of the subclavian vein and may reduce the need for open venous reconstruction.

Incidence, prevalence and mortality of chronic periaortitis: a population-based study.

OBJECTIVES: To evaluate the epidemiology, presentation and outcomes of patients with chronic periaortitis from 1998 through 2018. METHODS: An inception cohort of patients with incident chronic periaortitis from January 1, 1998 through December 31, 2018, in Olmsted County, Minnesota was identified based on comprehensive individual medical record review utilising the Rochester Epidemiology Project medical record linkage system. Inclusion required radiographic and/or histologic confirmation of periarterial soft tissue thickening around at least part of the infra-renal abdominal aorta or the common iliac arteries. Data were collected on demographic characteristics, clinical presentation, renal and radiographic outcomes, and mortality. Incidence rates were age and sex adjusted to the 2010 United States white population. RESULTS: Eleven incident cases of chronic periaortitis were identified during the study period. Average age at diagnosis was 61.8±13.4 years. The cohort included 9 men (82%) and 2 women (18%). Age- and sex-adjusted incidence rates per 100,000 population were 0.26 for females, 1.56 for males and 0.87 overall. Overall prevalence on January 1, 2015 was 8.98 per 100,000 population. Median (IQR) length of follow-up was 10.1 (2.5, 13.8) years. Overall mortality was similar to the expected age, sex, and calendar estimates of the Minnesota population with standardised mortality ratio (95% CI) for the entire cohort 2.07 (0.67, 4.84). CONCLUSIONS: This study reports the first epidemiologic data on chronic periaortitis in the United States. In this cohort of patients with chronic periaortitis, men were 4 times more commonly affected than women. Mortality was not increased compared to the general population.

Artificial intelligence for the evaluation of peripheral artery disease using arterial Doppler waveforms to predict abnormal ankle-brachial index.

BACKGROUND: Patients with peripheral artery disease (PAD) are at increased risk for major adverse limb and cardiac events including mortality. Developing screening tools capable of accurate PAD identification is a necessary first step for strategies of adverse outcome prevention. This study aimed to determine whether machine analysis of a resting Doppler waveform using deep neural networks can accurately identify patients with PAD. METHODS: Consecutive patients (4/8/2015 - 12/31/2020) undergoing rest and postexercise ankle-brachial index (ABI) testing were included. Patients were randomly allocated to training, validation, and testing subsets (70%/15%/15%). Deep neural networks were trained on resting posterior tibial arterial Doppler waveforms to predict normal (> 0.9) or PAD (⩽ 0.9) using rest and postexercise ABI. A separate dataset of 151 patients who underwent testing during a period after the model had been created and validated (1/1/2021 - 3/31/2021) was used for secondary validation. Area under the receiver operating characteristic curves (AUC) were constructed to evaluate test performance. RESULTS: Among 11,748 total patients, 3432 patients met study criteria: 1941 with PAD (mean age 69 ± 12 years) and 1491 without PAD (64 ± 14 years). The predictive model with highest performance identified PAD with an AUC 0.94 (CI = 0.92-0.96), sensitivity 0.83, specificity 0.88, accuracy 0.85, and positive predictive value (PPV) 0.90. Results were similar for the validation dataset: AUC 0.94 (CI = 0.91-0.98), sensitivity 0.91, specificity 0.85, accuracy 0.89, and PPV 0.89 (postexercise ABI comparison). CONCLUSION: An artificial intelligence-enabled analysis of a resting Doppler arterial waveform permits identification of PAD at a clinically relevant performance level.

Catheter directed compared to systemically delivered thrombolysis for pulmonary embolism: a systematic review and meta-analysis.

To compare the efficacy and safety of systemic and catheter directed thrombolysis for patients with pulmonary embolism. Pubmed and Cochrane Central Register of Controlled Trials were systematically searched from inception to May 31st 2020 to identify relevant studies. Outcomes of interest were in-hospital mortality and major bleeding including intracranial hemorrhage. We included 8 observational studies comprising 11,932 patients with PE. Catheter directed thrombolysis was associated with lower in-hospital mortality [RR 0.52; 95% confidence interval (CI) 0.40-0.68]. Although there was no difference in major bleeding by treatment strategy (RR 0.80; 95% CI 0.37-1.76), intracranial hemorrhage was lower in patients receiving catheter directed therapy (RR 0.66; 95% CI, 0.47-0.94).The certainty in these estimates was low. Non-randomized studies suggest that catheter directed delivery of thrombolytic therapy may be associated with lower in-hospital mortality and intracranial hemorrhage rates. These results may help inform management strategies for health care and pulmonary embolism response teams (PERT) involved in the management of high risk patients with massive or submassive pulmonary emboli.

Percutaneous MR Imaging-Guided Laser Ablation and Cryoablation for the Treatment of Pediatric and Adult Symptomatic Peripheral Soft Tissue Vascular Anomalies.

PURPOSE: To evaluate the safety and effectiveness of percutaneous magnetic resonance (MR) imaging-guided laser ablation and cryoablation for the treatment of symptomatic soft tissue vascular anomalies (VAs) of the trunk and extremities. MATERIALS AND METHODS: An institutional review board-approved retrospective review was undertaken of all pediatric and adult patients who underwent MR imaging-guided and monitored laser ablation and/or cryoablation for the treatment of symptomatic peripheral soft tissue VA. Preablation and postablation MR imaging was independently reviewed. Pain scores on the visual analog scale (0 to 10) and self-reported subjective symptomatic improvement were assessed. Change in VA size and pain scores were compared using a paired t test. RESULTS: Thirty patients (24 females; age, 10-75 years) with 34 VAs were treated for moderate to severe pain (n = 27) or swelling/mass effect (n = 3) with 60 total ablation sessions. The baseline maximum VA diameter was 9.5 cm ± 8.6. At baseline, all VAs (100%) demonstrated variable T2-weighted signal hyperintensity and enhancement. The baseline pain score was 6.4 ± 1.6. Clinical follow-up was available for 23 patients. At a mean follow-up time of 12.2 months ± 10.1, 19 of 20 (95%) patients treated for pain and 2 of 3 (67%) patients treated for swelling/mass effect reported partial or complete symptomatic relief. There was a significant decrease in the postablation pain scores (-5.7 ± 1.0, P < .001) and maximum VA size (-2.3 cm ± 2.7, P = .004), with >50% reduction in VA T2 signal (59%) and enhancement (73%). Nine of 30 (30%) patients experienced minor complications. CONCLUSIONS: MR imaging-guided and monitored percutaneous laser ablation and cryoablation appear to be safe and effective for the treatment of symptomatic peripheral soft tissue VAs.

Transcatheter closure of coronary artery fistula: A 21-year experience.

OBJECTIVES: To evaluate the outcomes of transcatheter coronary artery fistula (CAF) closure and to identify anatomic/procedural factors that may impact outcomes. BACKGROUND: Due to the rarity of CAF, reported experience with transcatheter closure remains limited and anatomic and procedural factors that may lead to unsuccessful closure, complications, or recanalization of CAF are unclear. METHODS: All patients who underwent transcatheter CAF closure at Mayo Clinic from 1997 to 2018 were retrospectively reviewed. CAF anatomic characteristics, procedural techniques, and clinical/angiographic outcomes were assessed. RESULTS: A total of 45 patients underwent transcatheter closure of 56 CAFs. The most commonly used devices were embolization coils in 40 (71.4%) CAFs, vascular occluders in 10 (17.8%), or covered stent in 2 (3.6%). Acute procedural success with no or trivial residual flow occurred in 50 (89.3%) CAFs. Residual flow was small in three (5.4%) and large in three (5.4%). Eight (17.8%) patients had complications, including device migration in three, intracranial hemorrhage from anticoagulation in one, and myocardial infarction (MI) in four. MI was a result of covered stent thrombosis or stagnation of flow after closure of large distal CAF. Twenty-two patients with 27 CAFs had follow-up angiography after successful index procedure at median time of 423 (IQ 97-1348) days. Of these, 23 (85.2%) had no/trace flow and 4 had large flow from recanalization. CONCLUSIONS: Transcatheter CAF closure is associated with a favorable acute procedural success and complication rate in selected patients. Procedural success and risk for complication are highly dependent on CAF anatomy and closure technique.

Outcomes of Onyx® Embolization of Type II Endoleaks After Endovascular Repair of Abdominal Aortic Aneurysms.

BACKGROUND: Type II endoleaks (T2ELs) are common following endovascular repair of abdominal aortic aneurysms (EVAR). Embolization with ethylene vinyl alcohol copolymer (Onyx) may present an effective treatment alternative for T2ELs. Due to limited data supporting its use, we sought to analyze outcomes of Onyx embolization for T2ELs. METHODS: Retrospective review of consecutive patients treated for T2ELs utilizing Onyx embolization agent from 2009-2018. All pre- and post-Onyx intervention CT scans were analyzed for diameter and volume changes with 3D reconstruction software. The primary outcomes were change in maximum AAA diameter and volume. Secondary outcomes included additional interventions, rupture, and mortality. A subset analysis was performed with patients with isolated T2ELs (no other types of endoleaks present). RESULTS: We identified 85 patients (73 males, mean age 77.6 ± 7.6 years) who underwent 112 Onyx interventions. Average time to first Onyx intervention after index EVAR was 3.3 ± 2.6 years and average sac growth was 6.3 ± 6.7 mm. Patients underwent mean 1.3 Onyx interventions using a mean of 4.9 ± 4.7 ml for treatment. Three complications occurred (Onyx extravasation, colon ischemia, and access site hematoma). Mean follow-up was 2.5 ± 2.1 years after initial Onyx treatment. At the most recent follow-up, sac diameter stabilization was seen in 47% and reduction >5 mm was seen in 19%. Sac growth of >5 mm was seen in 34% of patients following the first Onyx intervention. In our subset of isolated T2EL, 72% had sac stabilization or reduction >5 mm. Four patients experienced a ruptured aneurysm (3 had active type 1 endoleaks). Rupture-free survival was 95% at 5 years, and overall survival was 54% at 5 years. Notably, increasing Onyx interventions were not associated with sac stabilization or reduction (OR 0.6, P = 0.1). On multivariable analysis, AAA sac diameter stabilization or reduction was independently associated with BMI >30 kg/m2 (OR 4.2, P = 0.01) and having only 1 Onyx intervention (OR 3.8, P = 0.02). CONCLUSIONS: Onyx for embolization of T2ELs resulted in AAA sac diameter stabilization or reduction in 66% of patients, and up to 72% in isolated T2ELs. Further, increasing Onyx interventions were not associated with either aneurysm sac stabilization or reduction. Given its similar outcomes to other embolization strategies in the literature, Onyx embolization for management of T2ELs needs to be judiciously considered, particularly for T2ELs persisting after an initial Onyx embolization intervention.

Catheter based treatments for fibrosing mediastinitis.

Fibrosing mediastinitis is a rare, often debilitating and potentially lethal disease characterized by an exuberant fibroinflammatory response within the mediastinum. Patients typically present with insidious symptoms related to compression of adjacent structures including the esophagus, heart, airways, and cardiac vessels. Fibrosing mediastinitis is most often triggered by Histoplasmosis infection; however, antifungal and anti-inflammatory therapies are largely ineffective. While structural interventions aimed at alleviating obstruction can provide significant palliation, surgical interventions are challenging with high mortality and clinical experience with percutaneous interventions is limited. Here, we will review the presentation, natural history, and treatment of fibrosing mediastinitis, placing particular emphasis on catheter-based therapies.

Imaging Appearance and Nonsurgical Management of Pelvic Venous Congestion Syndrome.

Pelvic venous congestion syndrome (PVCS) is a challenging and complex cause of chronic pelvic pain in female patients. PVCS due to incompetent vein valves is the combination of gonadal vein reflux and pelvic venous engorgement in patients with chronic pelvic pain without other causes. However, pelvic venous engorgement and gonadal vein reflux can be seen in patients without pelvic pain, which makes obtaining a detailed history and physical examination important for workup and diagnosis. The underlying cause of PVCS may be incompetent gonadal vein valves or structural causes such as left renal vein compression with an incompetent gonadal vein valve (nutcracker syndrome) or iliac vein compression (May-Thurner configuration) with reflux into the ipsilateral internal iliac vein. Venography is considered the criterion standard for imaging diagnosis; however, more recently, US and MRI have been shown to provide adequate accuracy for diagnosis. Noninvasive imaging studies aid in the diagnosis of PVCS and also aid in pretreatment planning. When PVCS is caused by incompetent gonadal vein valves, treatment typically is performed by means of embolization via a minimally invasive catheter with excellent technical and clinical success rates. When PVCS is caused by venous obstruction, the obstruction must be treated first before gonadal vein embolization and sclerotherapy are considered. ©RSNA, 2019 Online supplemental material is available for this article.

Efficacy and safety of rivaroxaban compared to enoxaparin in treatment of cancer-associated venous thromboembolism.

BACKGROUND: Low molecular weight heparin (LMWH) is the guideline-endorsed treatment for cancer-associated venous thromboembolism (cVTE). Study objectives were to compare the efficacy and safety of rivaroxaban and enoxaparin in cVTE. METHODS: Using a cohort study design, consecutive patients with cVTE (3/1/2013-7/31/2016), enrolled in the Mayo Thrombophilia Clinic Direct Oral Anticoagulants Registry, were compared to contemporary cancer patients receiving enoxaparin. The cumulative incidence of venous thromboembolism (VTE) recurrence, major and clinically relevant non-major bleeding, and survival were assessed at 3 and 12 months. RESULTS: Ninety-eight patients received rivaroxaban (51% female, mean age 63 ± 12 years) and 168 enoxaparin (34.5% female, mean age 62 ± 15 years). The most common cancers included gastrointestinal/pancreatic, genitourinary and hematologic cancers. More than half of patients had pulmonary emboli at presentation. More than half had metastases, and two-thirds were receiving chemotherapy. At 3 months, there were no differences in VTE recurrence (rivaroxaban 1.0% vs enoxaparin 4.2%; P = .15), major bleeding (rivaroxaban 5.1% vs enoxaparin 3.6%; P = .55), or all-cause mortality (rivaroxaban 4.1% vs enoxaparin 8.9%; P = .14). At 12 months, these outcomes did not differ by treatment strategy. CONCLUSION: The results of this "real-world" experience with cVTE suggest that rivaroxaban may offer a safe and effective alternative to LMWH.

Is Long-Term Anticoagulation Required after Stent Placement for Benign Superior Vena Cava Syndrome?

PURPOSE: To identify whether symptom relief and stent patency vary with use of long-term anticoagulation after stent placement for benign superior vena cava (SVC) syndrome. MATERIALS AND METHODS: Patients with benign SVC syndrome treated with stent placement between January 1999 and July 2017 were retrospectively identified (n = 58). Average age was 49 years (range, 24-80 y); 34 (58%) were women, and 24 (42%) were men. Average follow-up was 2.4 years (range, 0.1-11.1 y, SD 2.6). Of cases, 37 (64%) were due to a long-term line/pacemaker, and 21 (36%) were due to fibrosing mediastinitis. After stent placement, 36 (62%) patients were placed on long-term anticoagulation, and 22 (38%) were not placed on anticoagulation. Percent stenosis was evaluated on follow-up imaging by dividing smallest diameter of the stent by a normal nonstenotic segment of the stent and multiplying by 100. RESULTS: Technical success was achieved in all cases. There was no significant difference in number of patients who reported a return of symptoms characteristic of benign SVC syndrome between the anticoagulated (16 of 36; 44.4%) and nonanticoagulated (11 of 22; 50%) groups (P = .68). There was no significant difference in the mean percent stenosis between the anticoagulated (40.4% ± 34.7% [range, 0-100%]) and nonanticoagulated (32.1% ± 29.2% [range, 1.7%-100%]) groups (P = .36). No significant difference was found in the time (days) between date of procedure and date of return of symptoms (anticoagulated, 735.9 d ± 1,003.1 [range, 23-3,851 d]; nonanticoagulated, 478 d ± 826.6 [range, 28-2,922 d]) (P = .49). There was no difference in primary patency between groups (P = .59). Finally, 1 patient (2.8%) in the anticoagulated group required surgical intervention, whereas none in the nonanticoagulated group required surgical intervention. CONCLUSIONS: No significant difference was observed in clinical and treatment outcomes in patients who did and did not receive anticoagulation after stent placement for benign SVC syndrome. Management of benign SVC syndrome after stent placement may not require anticoagulation if confirmed by additional studies.

Pulmonary embolism attenuation is a potential imaging biomarker for pulmonary artery hemodynamic improvement after catheter-directed thrombolysis.

This study examined the potential correlation between pulmonary embolism (PE) attenuation on computed tomography pulmonary angiography (CTPA) and pulmonary artery hemodynamic response to catheter-directed thrombolysis (CDT) in 10 patients with submassive PE. Treatment parameters, PE attenuation, clot burden, computed tomography signs of right ventricle dysfunction and right ventricular systolic pressure at echocardiography were retrospectively analyzed to determine correlation with pulmonary artery pressure improvement using Spearman correlation. A single reader, blinded to the treatment results, measured PE attenuation of all patients. There was a significant positive correlation between PE attenuation and absolute pulmonary artery pressure improvement with a Spearman correlation of 0.741, p=0.014. When attenuation was greater than or equal to the median (44.5 HU, n=5), CDT was associated with significantly better pulmonary artery pressure improvement ( p=0.037). Clot attenuation at CTPA may be a potential imaging biomarker for predicting pulmonary artery pressure improvement after CDT.

Autologous Mesenchymal Stem Cells Increase Cortical Perfusion in Renovascular Disease.

Atherosclerotic renovascular disease (RVD) reduces renal blood flow (RBF) and GFR and accelerates poststenotic kidney (STK) tissue injury. Preclinical studies indicate that mesenchymal stem cells (MSCs) can stimulate angiogenesis and modify immune function in experimental RVD. We assessed the safety and efficacy of adding intra-arterial autologous adipose-derived MSCs into STK to standardized medical treatment in human subjects without revascularization. The intervention group (n=14) received a single infusion of MSC (1.0 × 105 or 2.5 × 105 cells/kg; n=7 each) plus standardized medical treatment; the medical treatment only group (n=14) included subjects matched for age, kidney function, and stenosis severity. We measured cortical and medullary volumes, perfusion, and RBF using multidetector computed tomography. We assessed tissue oxygenation by blood oxygen level-dependent MRI and GFR by iothalamate clearance. MSC infusions were well tolerated. Three months after infusion, cortical perfusion and RBF rose in the STK (151.8-185.5 ml/min, P=0.01); contralateral kidney RBF increased (212.7-271.8 ml/min, P=0.01); and STK renal hypoxia (percentage of the whole kidney with R2*>30/s) decreased (12.1% [interquartile range, 3.3%-17.8%] to 6.8% [interquartile range, 1.8%-12.9%], P=0.04). No changes in RBF occurred in medical treatment only subjects. Single-kidney GFR remained stable after MSC but fell in the medical treatment only group (-3% versus -24%, P=0.04). This first-in-man dose-escalation study provides evidence of safety of intra-arterial infusion of autologous MSCs in patients with RVD. MSC infusion without main renal artery revascularization associated with increased renal tissue oxygenation and cortical blood flow.

Intervention radiology for venous thrombosis: early thrombus removal using invasive methods.

The post thrombotic syndrome is one of the most dreaded complications of proximal deep vein thrombosis. This syndrome leads to pain and suffering with leg swelling, recalcitrant ulceration and venous claudication which greatly impairs mobility and quality of life. The prevalence can be high in patients with iliofemoral venous involvement particularly in the setting of a proximal venous stenosis, such as occurs in May Thurner syndrome. Anticoagulation alone does not reduce the likelihood of this outcome. Compression therapy may be effective but garment discomfort limits its implementation. Pharmacomechanical thrombectomy, which combines catheter-directed thrombolysis with mechanical thrombus dissolution, provides an attractive treatment strategy for such patients. The rationale and delivery of pharmacomechanical thrombectomy, including patient selection and adjunctive antithrombotic therapy, will be reviewed in addition to tips and tricks for managing difficult patient scenarios.

Predictors and Outcomes of Postcontrast Acute Kidney Injury after Endovascular Renal Artery Intervention.

PURPOSE: To determine incidence, predictors, and clinical outcomes of postcontrast acute kidney injury (PC-AKI) following renal artery stent placement for atherosclerotic renal artery stenosis. MATERIALS AND METHODS: This retrospective study reviewed 1,052 patients who underwent renal artery stent placement for atherosclerotic renal artery stenosis; 437 patients with follow-up data were included. Mean age was 73.6 years ± 8.3. PC-AKI was defined as absolute serum creatinine increase ≥ 0.3 mg/dL or percentage increase in serum creatinine ≥ 50% within 48 hours of intervention. Logistic regression analysis was performed to identify risk factors for PC-AKI. The cumulative proportion of patients who died or went on to hemodialysis was determined using Kaplan-Meier survival analysis. RESULTS: Mean follow-up was 71.1 months ± 68.4. PC-AKI developed in 26 patients (5.9%). Patients with PC-AKI had significantly higher levels of baseline proteinuria compared with patients without PC-AKI (odds ratio = 1.38; 95% confidence interval, 1.11-1.72; P = .004). Hydration before intervention, chronic kidney disease stage, baseline glomerular filtration rate, statin medications, contrast volume, and iodine load were not associated with higher rates of PC-AKI. Dialysis-free survival and mortality rates were not significantly different between patients with and without PC-AKI (P = .50 and P = .17, respectively). CONCLUSIONS: Elevated baseline proteinuria was the only predictor for PC-AKI in patients undergoing renal artery stent placement. Patients who developed PC-AKI were not at greater risk for hemodialysis or death.

Atherosclerotic renal artery stenosis is associated with elevated cell cycle arrest markers related to reduced renal blood flow and postcontrast hypoxia.

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) reduces renal blood flow (RBF), ultimately leading to kidney hypoxia and inflammation. Insulin-like growth factor binding protein-7 (IGFBP-7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) are biomarkers of cell cycle arrest, often increased in ischemic conditions and predictive of acute kidney injury (AKI). This study sought to examine the relationships between renal vein levels of IGFBP-7, TIMP-2, reductions in RBF and postcontrast hypoxia as measured by blood oxygen level-dependent (BOLD) magnetic resonance imaging. METHODS: Renal vein levels of IGFBP-7 and TIMP-2 were obtained in an ARAS cohort (n= 29) scheduled for renal artery stenting and essential hypertensive (EH) healthy controls (n = 32). Cortical and medullary RBFs were measured by multidetector computed tomography (CT) immediately before renal artery stenting and 3 months later. BOLD imaging was performed before and 3 months after stenting in all patients, and a subgroup (N = 12) underwent repeat BOLD imaging 24 h after CT/stenting to examine postcontrast/procedure levels of hypoxia. RESULTS: Preintervention IGFBP-7 and TIMP-2 levels were elevated in ARAS compared with EH (18.5 ± 2.0 versus 15.7 ± 1.5 and 97.4 ± 23.1 versus 62.7 ± 9.2 ng/mL, respectively; P< 0.0001); baseline IGFBP-7 correlated inversely with hypoxia developing 24 h after contrast injection (r = -0.73, P< 0.0001) and with prestent cortical blood flow (r = -0.59, P= 0.004). CONCLUSION: These data demonstrate elevated IGFBP-7 and TIMP-2 levels in ARAS as a function of the degree of reduced RBF. Elevated baseline IGFBP-7 levels were associated with protection against postimaging hypoxia, consistent with 'ischemic preconditioning'. Despite contrast injection and stenting, AKI in these high-risk ARAS subjects with elevated IGFBP-7/TIMP-2 was rare and did not affect long-term kidney function.

Treatment of In-Stent Restenosis in Patients with Renal Artery Stenosis.

PURPOSE: To determine clinical outcomes of patients treated for renal artery in-stent restenosis (ISR) with atherosclerotic renal artery stenosis. MATERIALS AND METHODS: A retrospective review was performed of the clinical data of all patients who underwent renal artery stent placement for atherosclerotic renal artery stenosis from 1996 to 2009. Medical records of patients were reviewed for relevant clinical history, including blood pressure, antihypertensive medications, and renal function data before and after an intervention. In 1,052 patients, 1,090 renal artery stent placements were performed. Of these, 101 stents in 79 patients developed ISR, which was treated with either percutaneous transluminal angioplasty (PTA) or repeat stent placement. Procedural details, including modality of intervention, stent diameter, and time to restenosis, were recorded. Hypertensive agent and use of statins were recorded. Univariate analysis was performed to identify risk factors associated with restenosis after treatment of ISR. RESULTS: Patients treated with repeat stent placement were 6.89 times more likely to lose patency after treatment than patients treated with PTA (P < .01). No additional clinical or procedural factor, including smoking history; presence of cardiac, renal, or metabolic disease; use of statin at time of ISR treatment; or diameter of treatment (stent or PTA), had a significant association with duration of stent or angioplasty patency. CONCLUSIONS: Treatment of renal artery ISR with PTA among patients with atherosclerotic renal artery stenosis has a lower rate of subsequent ISR compared with repeat stent placement.

Impact of Chronic Kidney Disease on Clinical Outcomes of Endovascular Treatment for Femoropopliteal Arterial Disease.

PURPOSE: To evaluate effect of chronic kidney disease (CKD) on all-cause mortality, major adverse limb event (MALE), MALE and postoperative death (MALE + POD), and amputation after endovascular treatment of femoropopliteal disease. MATERIALS AND METHODS: A retrospective review from January 2002 to October 2011 was performed of 440 patients who underwent endovascular treatment of symptomatic femoropopliteal disease for claudication (n = 251) or critical limb ischemia (CLI) (n = 267). CKD stage was divided based on Kidney Dialysis Outcomes Quality Initiative classification. Outcomes and factors associated with amputation, MALE, and MALE + POD were determined. RESULTS: Patients with diabetes (hazard ratio [HR] = 2.2; 95% confidence interval [CI], 1.3-3.6; P = .002) and runoff score of 0 or 1 (HR = 2.0; 95% CI, 1.2-3.4; P = .01) relative to runoff score of 3 were at increased risk of amputation. Patients with baseline glomerular filtration rate < 45 mL/min/1.73 m(2) had a 17% increase in amputation for every 5-point decrease < 45 mL/min/1.73 m(2) (95% CI, 1.09-1.26; P < .001). Increase of 10 years in age (HR = 1.9; 95% CI, 1.5-2.3; P < .001), TransAtlantic Inter-Society Consensus class of C/D relative to A/B (HR = 1.6; 95% CI, 1.1-2.2; P = .01), and CLI (HR = 2.4; 95% CI, 0.5-0.9; P < .001) were associated with increased mortality. Female sex was associated with decreased risk of mortality (HR = 0.7; 95% CI, 0.5-0.9; P = .01). CONCLUSIONS: Worsening CKD is associated with higher amputation rates, all-cause mortality, and MALE + POD in patients undergoing endovascular treatment of femoropopliteal disease.