Ulku C. Turba

Outcomes of Covered Kissing Stent Placement Compared with Bare Metal Stent Placement in the Treatment of Atherosclerotic Occlusive Disease at the Aortic Bifurcation

PURPOSE To review the outcomes with the use of balloon-expandable covered iliac kissing stents as compared with bare metal stents in the treatment of atherosclerotic disease at the aortic bifurcation. MATERIALS AND METHODS A review of consecutive patients from a single institution with atherosclerotic occlusive disease at the aortic bifurcation treated with balloon-expandable kissing stents was performed between January 1, 2002, and September 1, 2007. Fifty-four patients were identified and divided into two groups: those with bare metal stents and those with covered stents. Technical and clinical success (Fontaine classification), complications, and patency at follow-up were documented. RESULTS Twenty-six patients (17 men, nine women; mean age, 61 years; age range, 39-79 years) received covered stents and 28 patients (15 men, 13 women; mean age, 61 years; age range, 38-82 years) received bare metal stents. Technical success was achieved in 100% of patients in both groups. Major complications occurred in three of the 26 (11%) with covered stents (P = .66) and two of the 28 patients (7%) with bare metal stents. The median follow-up was 21 months (20 months for covered stents vs 25 months for bare metal stents; range, 1-62 months). Twenty-two of the 26 patients (85%) with covered stents had sustained improvement in clinical symptoms during the follow-up period compared with 15 of the 28 patients (54%) with bare metal stents (P = .02). Primary patency rates at 1 and 2 years were 92% and 92%, respectively, for covered stents and 78% and 62% for bare metal stents (P = .023). CONCLUSIONS The use of covered balloon-expandable kissing stents for atherosclerotic aortic bifurcation occlusive disease provides superior patency at 2 years as compared with bare metal balloon-expandable stents.

Transcatheter Renal Artery Embolization: Clinical Applications and Techniques

Renal artery embolization is a minimally invasive procedure that is increasingly being used for treatment of a wide range of conditions. The main indications for renal artery embolization include (1) prenephrectomy and preradiofrequency ablation infarction of renal tumors, (2) management of renal angiomyolipomas, (3) palliations of unresectable renal malignancy, (4) renal hemorrhage (life-threatening or chronic debilitating hematuria), (5) arteriovenous fistulas, (6) vascular malformations, (7) renal artery aneurysms and pseudoaneurysms, and other less common indications, such as severe hydronephrosis and hypertension. A variety of embolic materials are available, such as metal coils, sclerosants (glue, Onyx, absolute ethanol, lipiodol), and particulate embolic agents (polyvinyl alcohol particles and embospheres). Selection of the appropriate agent depends on the clinical application, technical and clinical endpoints, as well as the pathology lesion(s) targeted. Renal artery embolization can be performed alone or in combination with remodeling techniques, stent-grafting, and balloon- or stent-assisted coiling in more complicated cases. The procedure is generally regarded as safe and effective for diverse applications and is considered as an evolving area in the field of endoluminal therapy.

Short-term rebleeding rates for isolated gastric varices managed by transjugular intrahepatic portosystemic shunt versus balloon-occluded retrograde transvenous obliteration.

PURPOSE To assess the short-term rebleeding rate associated with the use of a transjugular intrahepatic portosystemic shunt (TIPS) compared with balloon-occluded retrograde transvenous obliteration (BRTO) for management of gastric varices (GV). MATERIALS AND METHODS A single-center retrospective comparison of 50 patients with bleeding from GV treated with a TIPS or BRTO was performed. Of 50 patients, 27 (17 men and 10 women; median age, 55 y; range, 31-79 y) received a TIPS with covered stents, and 23 (12 men and 11 women; median age, 52 y; range, 23-83 y) underwent a BRTO procedure with a foam sclerosant. All study subjects had clinical and endoscopic evidence of isolated bleeding GV and were hemodynamically stable at the time of the procedure. Clinical and endoscopic follow-up was performed. Kaplan-Meier analysis was used to evaluate rebleeding rates from the GV. RESULTS The technical success rate was 100% in the TIPS group and 91% in the BRTO group (P = .21). Major complications occurred in 4% of the patients receiving TIPS and 9% of patients the undergoing BRTO (P = .344). Encephalopathy was reported in 4 of 27 (15%) patients in the TIPS group and in none of the patients in the BRTO group (0%; P = .12). At 12 months, the incidence of rebleeding from a GV source was 11% in the TIPS group and 0% in the BRTO group (P = .25). CONCLUSIONS BRTO appears to be equivalent to TIPS in the short-term for management of bleeding GV. Further comparative studies are warranted to determine optimal management strategies in individual patients.

Endovascular Therapy for Hepatic Artery Stenosis and Thrombosis Following Liver Transplantation

Purpose: To evaluate the effectiveness of endovascular management of steno-oclusive disease in liver transplants. Methods: Retrospective review of liver transplant recipients with hepatic artery stenosis (HAS) or thrombosis (HAT) was performed. The HAS group was treated with balloon angioplasty with selective stent placement. The HAT group was treated with catheter-directed thrombolysis. Primary, unassisted, and assisted patency and graft survival rates were calculated. Results: In all, 31 patients were identified (21 males; mean age, 51 years). A total of 25 of 31 (81%) patients had HAS and 6 of 31 (19%) had HAT. Collectively, a total of 35 endovascular procedures were performed to treat HAS in 25 patients. Overall technical success rate was 91%, with 11% major complication rate. Primary-assisted patency rate and graft survival at 6 and 12 months were 87% and 81%, and 76% and 72%, respectively. Only 1 successful thrombolysis of HAT was achieved. Conclusion: Endovascular management is effective for HAS but not for HAT.

High spatial resolution magnetic resonance imaging of cystic adventitial disease of the popliteal artery

High spatial resolution magnetic resonance imaging (MRI) of patients with cystic adventitial disease can demonstrate connections between cysts in the adventitia and the adjacent joint, which is important for successful treatment. The inability to identify these during surgery can lead to a recurrence; thus, high spatial resolution MRI has the potential to affect therapy. This article presents the high spatial resolution MRI findings of cystic adventitial disease in a series of three consecutive patients and discusses the relevance of these findings to the etiology and therapy.

Effect of transjugular intrahepatic portosystemic shunt placement on renal function: A 7-year, single-center experience

PURPOSE Transjugular intrahepatic portosystemic shunt (TIPS) creation has been shown to improve renal function in small series of patients with hepatorenal syndrome. The present study examined the effect of TIPS creation on renal function in a large series of patients undergoing TIPS creation who had varying degrees of baseline renal function. MATERIALS AND METHODS All de novo TIPS creations during a 7-year period at a single institution were retrospectively reviewed regardless of indication. Pre- and postprocedural laboratory values were obtained and used to calculate Model for End-Stage Liver Disease (MELD) scores and glomerular filtration rates. Subanalysis was performed based on degree of renal insufficiency and indication for the procedure. RESULTS A total of 201 successful conventional TIPS procedures were identified. Of those, 72 patients were excluded for lack of follow-up, death during the same hospitalization, lack of TIPS function, or end-stage renal failure requiring dialysis before TIPS creation, leaving 129 procedures. Patients with preprocedural creatinine levels of 1.2-1.9 mg/dL (n = 45) showed an improvement in mean creatinine from 1.5 to 1.1 mg/dL (P < 10(-12)) and patients with preprocedure creatinine levels greater than 2.0 mg/dL (n = 21) showed an improvement from 2.8 to 1.5 mg/dL (P < 10(-5)). MELD scores decreased in patients with creatinine levels greater than 2.0 mg/dL from 22.1 to 19.2 (P < 0.005) but increased in all other patient groups. Amount of iodinated contrast medium administered did not affect creatinine level changes. CONCLUSIONS TIPS creation improves renal dysfunction in chronic liver disease. Patients with poorer renal function benefit the most from TIPS creation.

Normal renal arterial anatomy assessed by multidetector CT angiography: Are there differences between men and women?

The purpose of this study was to determine renal arterial anatomy and gender differences in adults without renovascular disease using multidetector computed tomography angiography (MDCTA). MDCTA datasets of 399 patients were retrospectively reviewed. Measurements of the aortorenal diameters, the angulation of the renal ostia and pedicles as well as the distance between the origins of the renal arteries were measured. Differences in measurements between genders were tested for statistical significance using analysis of variance (ANOVA) and Pearsons Chi‐Square tests. A total of 798 renal arteries were available for analysis in 207 female (mean age = 52.91 years) and 192 male patients (mean age = 53.04 years). Female patients were found to have smaller aortae (at the level of the right renal ostium) and bilateral renal arteries than males (mean aortic diameter M/F = 18.33/15.89 mm, mean right renal artery ostial diameter M/F = 5.06/4.59 mm, mean left ostial renal diameter M/F = 5.14/4.66 mm) (p < .001). There was no statistical significance for the renal ostia level in relation to the vertebrae and the majority of renal arteries originated at the L1 and L2 levels. The longitudinal distance between right and left renal artery ostia ranged from 0 to 32 mm (mean = 4,6 mm, median = 5mm). The mean anteroposterior orientation of the right renal ostia was M/F = 29.45°/28.20°, and M/F = −7.96°/−11.14° for left renal artery ostia. The mean anteroposterior orientation of the right renal pedicle was M/F = 41.37°/44.34° and M/F = 42.31°/43.95° for the left pedicle. There are some differences in normal renal arterial anatomy between genders. Normal renal arterial information is useful not only for planning and performing of endovascular and laparoscopic urologic procedures, but also for medical device development. Clin. Anat. 22:236–242, 2009.

Incidence and Management of Inferior Vena Cava Filter Thrombus Detected at Time of Filter Retrieval

PURPOSE To evaluate inferior vena cava (IVC) venograms (ie, cavograms) before filter retrieval to determine the incidence and volume of filter thrombus relative to filter dwell time and evaluate subsequent changes in thrombus volume with additional anticoagulation. MATERIALS AND METHODS IVC filter retrieval attempts between December 2002 and June 2010 were retrospectively reviewed to determine the incidence of filter thrombus and estimate thrombus volume on a preretrieval cavogram. Correlation between filter dwell times (assessed at 30-d intervals) and incidence and volume of thrombus was assessed. Follow-up images and management of filters with thrombus that were not initially removed were analyzed. RESULTS A total of 463 retrieval attempts were performed in 440 patients, with a mean filter dwell time of 95 days ± 145 (SD; range, 0-1,762 d). Thirty (6.5%) had filter thrombus on initial cavograms, with a mean thrombus volume of 2.8 cm(3) ± 7.3 (range, 0.04-40.02 cm(3)). Incidence rate and estimated thrombus volume were highest in the 0-30-day dwell interval (8.0% and 6.3 cm(3), respectively) and decreased at subsequent time intervals. On linear regression analysis, incidence of filter thrombus was inversely related to dwell time (P < .05; correlation coefficient, -0.86). Seven patients with thrombus underwent additional anticoagulation for a mean of 48 days ± 25 (range, 14-90 d); thrombus resolved completely in five (71%) and partially in one (14%), and increased in one (14%). CONCLUSIONS The incidence of filter thrombus at the time of filter retrieval appears to decrease with dwell time. If thrombus is detected, an additional period of anticoagulation is likely to reduce the thrombus burden and facilitate later retrieval.

Transcatheter Renal Artery Embolization for Management of Renal and Adrenal Tumors

Transcatheter arterial embolization is a minimally invasive procedure that is increasingly used for the management of angiomyolipomas and to augment and/or palliate the management of malignant renal and adrenal neoplasms. The most common indications for renal artery embolization include (1) prenephrectomy and preradiofrequency ablation infarction of renal tumors, (2) management of renal angiomyolipomas, (3) palliations of unresectable renal malignancy, and (4) malignant renal hemorrhage (life-threatening or chronic debilitating hematuria). The increasing use of renal artery embolization for these conditions reflects the procedures effectiveness and safety. Although there is less extensive literature available regarding the use of transcatheter embolization of adrenal tumors, this technique appears to be effective and safe for palliation and preadrenalectomy of adrenal metastatic disease, adrenocortical carcinomas, as well as treatment of symptomatic aldosteronomas. This article reviews the indications and techniques involved in performing transcatheter arterial embolization for renal and adrenal tumors.

Chronic mesenteric ischaemia: 28-year experience of endovascular treatment

AbstractObjectiveTo report the outcomes associated with endovascular therapy for patients with chronic mesenteric ischemia (CMI).MethodsA retrospective review of patients who underwent endovascular therapy for CMI between April 1981 and September 2009 at a single institution was performed. Procedural details, mesenteric arteries treated, technical and clinical success rates, outcomes per patient and per vessel were assessed.ResultsIn 166 patients treatment was attempted using a variety of balloon and stent platforms during the 28-year period. The technical success rate was 97% per patient and 94% per vessel. The technical success rate of stenting (99.4%) was higher than for percutaneous transluminal angioplasty (PTA; 86%; P = 0.0001). Immediate clinical improvement was seen in 146 out of 166 (88.2%). The type of guidewire or device platform, brachial vs. femoral artery access, balloon and/or stent diameters used, and stenosis vs. occlusion had no statistical impact on mortality or the primary patency of any mesenteric artery outcomes. The outcome of the superior mesenteric artery (SMA) with PTA appears to be superior to that of stenting (P = 0.014).ConclusionTechnical success rates are improved with the use of stents; however, PTA use in the SMA seems to offer better primary patency rates.Key Points• Superior mesenteric artery (SMA) stenosis is often responsible for ischaemic symptoms. • Treatment with percutaneous transluminal angioplasty (PTA) seems superior to stenting • Although technical success rates are improved with the use of stents. • Higher mortality in the elderly and those presenting with nausea/vomiting/bloody stools.