Ripal T. Gandhi

Endovascular Treatment of Visceral and Renal Artery Aneurysms

PURPOSEnTo analyze early and midterm results of endovascular treatment of visceral aneurysms regarding technical considerations, technical success rate, aneurysm rupture, and end-organ ischemia.nnnMATERIALS AND METHODSnEndovascular treatment of 41 visceral and renal artery aneurysms (VAAs) in 40 consecutive patients (25 women; mean age, 59.4 y ± 16.2) was retrospectively reviewed. The series included 30 true aneurysms and 11 pseudoaneurysms in renal (n = 17), splenic (n = 13), hepatic (n = 4), celiac (n = 4), gastroduodenal (n = 2), and middle colic (n = 1) arteries. Demographic, clinical, procedural, and follow-up data were analyzed.nnnRESULTSnForty-one aneurysms underwent endovascular treatment. Hypertension (73%) and hyperlipidemia (32%) were the most common associated comorbidities. Nineteen patients presented with symptoms of pain (15%) or rupture (32%) in 10 pseudoaneurysms (91%) and nine true aneurysms (30%; P = .0007). The most commonly used technique (93%) was coil embolization with (15%) or without (78%) other endovascular agents. The rate of technical success (cessation of hemorrhage or blood flow into aneurysm sac) was 98%. There was no periprocedural mortality. Mean hospital stays were 1 and 2 days for asymptomatic and symptomatic patients, respectively. Mean clinical follow-up was 44.5 months; mean imaging follow-up was 11.7 months. The only complication was an intraprocedural thromboembolic event in one case (3%). Follow-up imaging evidence of end-organ partial infarct was detected in six patients (21%), with no clinical evidence of organ insufficiency.nnnCONCLUSIONSnEndovascular treatment of VAAs is a safe and highly successful procedure. Associated side effects such as distal embolization and end-organ infarcts were not found to be clinically significant.

Retrievable Inferior Vena Cava Filters: Factors that Affect Retrieval Success

PurposeTo report and analyze the indications, procedural success, and complications of retrievable inferior vena cava filters (rIVCF) placement and to identify parameters that influence retrieval attempt and failure.MethodsBetween January 2005 and December 2010, a total of 200 patients (80 men, median age 67xa0years, range 11–95xa0years) received a rIVCF with the clinical possibility that it could be removed. All patients with rIVCF were prospectively entered into a database and followed until retrieval or a decision not to retrieve the filter was made. A retrospective analysis of this database was performed.ResultsSixty-one percent of patients had an accepted indication for filter placement; 39% of patients had a relative indication. There was a tendency toward a higher retrieval rate in patients with relative indications (40% vs. 55%, Pxa0=xa00.076). Filter placement was technically successful in all patients, with no procedure-related mortality. The retrieval rate was 53%. Patient age of >80xa0years (odds ratio [OR] 0.056, Pxa0>xa00.0001) and presence of malignancy (OR 0.303, Pxa0=xa00.003) was associated with a significantly reduced probability for attempted retrieval. Retrieval failure occurred in 7% (6 of 91) of all retrieval attempts. A time interval ofxa0>xa090xa0days between implantation and attempted retrieval was associated with retrieval failure (OR 19.8, Pxa0=xa00.009).ConclusionsPatient age >80xa0years and a history of malignancy are predictors of a reduced probability for retrieval attempt. The rate of retrieval failure is low and seems to be associated with a time interval of >90xa0days between filter placement and retrieval.

Reliability and Accuracy of Simple Visual Estimation in Assessment of Peripheral Arterial Stenosis

PURPOSEnTo evaluate reliability, accuracy, and agreement of simple visual estimation (SVE) in determining the degree of peripheral arterial stenosis compared with calibrated measurements.nnnMATERIALS AND METHODSnIn 2 sessions, 23 interventionists with a wide range of experience and subspecialty training reviewed 42 angiographic images of lower extremity and carotid arteries (21 iliofemoral arteries and 21 carotid arteries). An independent physician measured all lesions using manual calipers. Intrarater and interrater reliability were assessed by intraclass correlation. A ± 5% error was considered the threshold for accuracy, and weighted κ statistics were computed to assess agreement with respect to the degree of stenosis (< 50%, nonsignificant; 50%-80%, significant; > 80%, severe).nnnRESULTSnIntrarater reliability of SVE was 0.99, and interrater reliability was 0.83. Accuracy varied from 52.8% for images of severe stenosis to 26.5% and 18.1% for significant and nonsignificant stenosis, respectively (P < .001). Agreement between SVE and caliper with regard to degree of stenosis was good (weighted κ 0.56) overall with correct classification ranging from 92.6% for severe stenosis to 53.4% and 68.2% for significant and nonsignificant stenosis, respectively (P < .001). Misclassification of nonsignificant and significant stenosis was more frequent for carotid arteries than for lower extremities.nnnCONCLUSIONSnDespite high reliability, SVE of peripheral arterial stenosis has limited accuracy in determining the exact degree of stenosis. Although severe stenosis is readily identified by SVE, arterial stenosis of < 80% is frequently overestimated, especially for carotid arteries, and should be confirmed by caliper assessment.

Lightweight Bilayer Barium Sulfate–Bismuth Oxide Composite Thyroid Collars for Superior Radiation Protection in Fluoroscopy-guided Interventions: A Prospective Randomized Controlled Trial

PURPOSEnTo test whether newer bilayer barium sulfate-bismuth oxide composite (XPF) thyroid collars (TCs) provide superior radiation protection and comfort during fluoroscopy-guided interventions compared with standard 0.5-mm lead-equivalent TCs.nnnMATERIALS AND METHODSnInstitutional review board approval and written informed consent were obtained for this HIPAA-compliant study, and 144 fluoroscopy-guided vascular interventions were included at one center between October 2011 and July 2012, with up to two operators randomly assigned to wear XPF (n = 135) or standard 0.5-mm lead-equivalent (n = 121) TCs. Radiation doses were measured by using dosimeters placed outside and underneath the TCs. Wearing comfort was assessed at the end of each procedure on a visual analog scale (0-100, with 100 indicating optimal comfort). Adjusted differences in comfort and radiation dose reductions were calculated by using a mixed logistic regression model and the common method of inverse variance weighting, respectively.nnnRESULTSnPatient (height, weight, and body mass index) and procedure (type and duration of intervention, operator, fluoroscopy time, dose-area product, and air kerma) data did not differ between the XPF and standard groups. Comfort was assessed in all 256 measurements. On average, the XPF TCs were 47.6% lighter than the standard TCs (mean weight ± standard deviation, 133 g ± 14 vs 254 g ± 44; P < .001) and had a significantly higher likelihood of a high level of comfort (visual analog scale >90; odds ratio, 7.6; 95% confidence interval: 3.0, 19.2; P < .001). Radiation dose reduction provided by the TCs was analyzed in 117 data sets (60 in the XPF group, 57 in the standard group). The mean radiation dose reductions (ie, radiation protection) provided by XPF and standard TCs were 90.7% and 72.4%, with an adjusted mean difference of 17.9% (95% confidence interval: 7.7%, 28.1%; P < .001) favoring XPF.nnnCONCLUSIONnXPF TCs are a lightweight alternative to standard 0.5-mm lead-equivalent TCs and provide superior radiation protection during fluoroscopy-guided interventions.

Endovascular Access for Challenging Anatomies in Peripheral Vascular Interventions

Vascular interventionalists continue to expand the scope and breadth of endovascular procedures that we offer to our patients. However, we often have to overcome various anatomical and technical challenges to deliver an endovascular device. This article should give the modern interventionalist an array of technical tips and tricks to enable them to overcome various challenging anatomical features such as vessel tortuosity, vascular calcifications, and increasing abdominal pannus. We also hope to elucidate alternative accesses such as radial access, pedal access, popliteal access, and direct stent access as well as direct aortic access.

The Influence of Statin Therapy on Restenosis in Patients Who Underwent Nitinol Stent Implantation for de Novo Femoropopliteal Artery Disease: Two-Year Follow-up at a Single Center

PURPOSEnTo determine whether statin therapy is associated with reduced restenosis following nitinol stent implantation for de novo femoropopliteal artery disease.nnnMATERIALS AND METHODSnA total of 135 limbs in 135 patients (mean age, 72 y) implanted with nitinol stents in femoropopliteal occlusions were analyzed (statin arm, n = 91; nonstatin arm, n = 44). The patients were treated with one type of nitinol stent.nnnRESULTSnAt baseline, lesions and procedural characteristics were comparable between groups, except that the statin group had more hypertension, coronary artery disease, and hyperlipidemia. There were significant differences in the incidence of binary restenosis between groups at 1 year (45.5% for nonstatin group vs 28.6% for statin group; P = .05) and 2 years (56.8% for nonstatin group vs 38.5% for statin group; P = .04). Primary patency rates at 1 year were 50.5% in the nonstatin group and 72.5% in the statin group (P = .01). Two-year target lesion revascularization rates were 54.5% in the nonstatin group and 35.2% in the statin group (P = .03). On univariate analysis, statin therapy was associated with decreased relative risk of binary restenosis at 1 year (odds ratio [OR], 0.480; 95% confidence interval [CI], 0.227-1.014; P = .050). On multivariate analysis, statin therapy did not significantly affect the odds of binary restenosis (OR, 0.415; 95% CI, 0.071-2.437; P = .330).nnnCONCLUSIONSnThe incidence of binary restenosis was significantly lower in the statin group than in the nonstatin group following nitinol stent implantation for de novo femoropopliteal artery disease.

Aortic aneurysm pressure sensors can be of value in the acute postoperative setting.

Purpose: To report on a case that demonstrates the use and current limits of abdominal aortic pressure sensor devices. Case report: An 83-year-old, high-risk patient underwent endovascular aortic repair (EVAR) of an infrarenal aortic aneurysm (maximum aneurysm diameter: 6.5 cm) with implantation of a pressure sensor device. At the end of the procedure and on the first postoperative day, the sensor detected persistent high pressures in the aneurysm sac, indicating an endoleak that could not be visualized on the intraoperative completion angiography but was confirmed on duplex ultrasound. During repeated angiography (postoperative day 6), again no endoleak could be detected, this time corresponding with the sensor reading that was unfortunately not interrogated again before the reintervention. Conclusion: Pressure sensor devices provide a useful, additional diagnostic tool in detecting and following endoleaks after EVAR and can help guide decisions regarding reinterventions.

Technical Approach to Antegrade Femoral Access

The number of endovascular procedures for treatment of peripheral arterial disease continues to increase as minimally invasive procedures have become the first-approach solution for lower extremity arterial lesions of any complexity, including Trans-Atlantic Inter-Society Consensus Document on Management of Peripheral Arterial Disease (TASC) II category C and D. Although the usual treatment strategy has been to access the contralateral common femoral artery (CFA), an ipsilateral, antegrade CFA approach has certain advantages. The greatest advantages are the decrease in the access-to-lesion distance, which in turn improves the mechanical advantage and responsiveness of the tools used to perform the intervention. In certain clinical situations such as prior endovascular aneurysm repair, aortobifemoral surgical bypass, iliac kissing stents, and aortoiliac occlusive disease, an antegrade approach may be mandatory. In this article, we describe our institutional thought process and techniques for performing a successful antegrade puncture of the CFA, as well as highlight some pitfalls and the associated complication rates of which to be aware.

Influence of Statin Therapy on Aneurysm Sac Regression after Endovascular Aortic Repair

PURPOSEnTo determine whether statin therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular aneurysm repair (EVAR).nnnMATERIALS AND METHODSnA total of 109 patients treated with EVAR were retrospectively analyzed (no-statin group, n = 45; statin group, n = 64). The primary endpoint was the incidence of AAA sac regression. To investigate independent predictors of AAA sac regression, regression analysis was performed. The mean age was 74 years (range, 55-90 y), and 87.2% of patients were men.nnnRESULTSnThe no-statin group had higher rates of AAA sac regression than the statin group at 1 year (no-statin group, 66.7%; statin group, 45.3%; P = .028). The incidence of AAA sac regression increased over time in the statin group, and no statistical difference was seen between the two groups at 2 years (no-statin group, 66.7%; statin group, 57.8%; P = .350). The difference between the changes in maximum AAA diameter was significant between groups at 1 year (no-statin group vs statin group, -4.9 mm ± 5.9; P = .041), but the difference did not reach statistical significance at 2 years (no-statin group, -10.0 mm ± 10.1; statin group, -8.0 mm ± 9.6; P = .306). Statin therapy was not associated with AAA sac regression on univariate (odds ratio [OR], 0.685; 95% confidence interval [CI], 0.310-1.516; P = .351) and multivariate analyses (OR, 0.617; 95% CI, 0.215-1.772; P = .369).nnnCONCLUSIONSnStatin therapy had no effect on AAA sac regression at 2 years. There is insufficient evidence to recommend statin therapy for AAA sac regression.

Percutaneous Large Arterial Access Closure Techniques

Endovascular repair has replaced open surgical repair as the standard of care for treatment of abdominal and thoracic aortic aneurysms in appropriately selected patients owing to its decreased morbidity and length of stay and excellent clinical outcomes. Similarly, there is a progressive trend toward total percutaneous repair of the femoral artery using percutaneous suture-mediated closure devices over open surgical repair due to decreased complications and procedure time. This article describes the techniques of closure for large-bore vascular access most commonly used in endovascular treatment of abdominal and thoracic aortic aneurysms, but could similarly be applied to any procedure requiring large-bore arterial access, such as transcatheter aortic valve replacement.