Renal artery sympathetic denervation: observations from the UK experience.

BACKGROUND: Renal denervation (RDN) may lower blood pressure (BP); however, it is unclear whether medication changes may be confounding results. Furthermore, limited data exist on pattern of ambulatory blood pressure (ABP) response-particularly in those prescribed aldosterone antagonists at the time of RDN. METHODS: We examined all patients treated with RDN for treatment-resistant hypertension in 18 UK centres. RESULTS: Results from 253 patients treated with five technologies are shown. Pre-procedural mean office BP (OBP) was 185/102 mmHg (SD 26/19; n = 253) and mean daytime ABP was 170/98 mmHg (SD 22/16; n = 186). Median number of antihypertensive drugs was 5.0: 96 % ACEi/ARB; 86 % thiazide/loop diuretic and 55 % aldosterone antagonist. OBP, available in 90 % at 11 months follow-up, was 163/93 mmHg (reduction of 22/9 mmHg). ABP, available in 70 % at 8.5 months follow-up, was 158/91 mmHg (fall of 12/7 mmHg). Mean drug changes post RDN were: 0.36 drugs added, 0.91 withdrawn. Dose changes appeared neutral. Quartile analysis by starting ABP showed mean reductions in systolic ABP after RDN of: 0.4; 6.5; 14.5 and 22.1 mmHg, respectively (p < 0.001 for trend). Use of aldosterone antagonist did not predict response (p > 0.2). CONCLUSION: In 253 patients treated with RDN, office BP fell by 22/9 mmHg. Ambulatory BP fell by 12/7 mmHg, though little response was seen in the lowermost quartile of starting blood pressure. Fall in BP was not explained by medication changes and aldosterone antagonist use did not affect response.

Effectiveness of stent-graft placement for salvage of dysfunctional arteriovenous hemodialysis fistulas.

PURPOSE: To determine the clinical effectiveness of stent-graft placement in dysfunctional autogenous hemodialysis fistulas. MATERIALS AND METHODS: Between September 2006 and June 2008, 24 Fluency Plus stent-grafts were inserted in 17 patients with failing autogenous hemodialysis fistulas (two radiocephalic, 12 brachiocephalic, and three brachiobasilic). Six fistulas were thrombosed at presentation. Indications for stent-graft insertion included 10 residual stenoses, six pseudoaneurysms, and one fistuloplasty-induced rupture. Fistula function before and after intervention was assessed with ultrasound dilution technique. RESULTS: The technical success rate was 100%, as were the anatomic and clinical success rates. Via Kaplan-Meier method, the primary access patency rates were 94.1% at 3 months (95% CI, 0.461-0.995) and 88.2% at 6 and 12 months (95% CI, 0.468-0.980). The primary lesion patency rate was 94.1% (95% CI, 0.650-0.992) at 3, 6, and 12 months. The secondary access patency rate had a point estimate of 100% at 3 months, and was 93.8% (95% CI, 0.632-0.991) at 6 and 12 months. Univariate analysis suggested that male sex and left-sided accesses were associated with a longer primary access patency rate (P = .02). The binary restenosis rate at 6 months was 5.9%. Mean transonic flow rates were 667.5 mL/min before intervention and 2,076.0 mL/min after intervention (P = .03, Wilcoxon signed-rank test). No patients were lost to follow-up. CONCLUSIONS: Stent-graft placement in dysfunctional autogenous hemodialysis fistulas is technically feasible and effective in preserving function and preventing access abandonment, with patency rates that exceed historical patency rates with angioplasty and/or uncovered stents.

The use of dynamic volumetric CT angiography (DV-CTA) for the characterization of endoleaks following fenestrated endovascular aortic aneurysm repair (f-EVAR).

Accurate endoleak classification is essential following fenestrated endovascular aneurysm repair (f-EVAR). Both endoleak type and exact source of endoleak have implications upon the urgency and complexity of future management strategies. Herein we report on a patient with a documented endoleak post-f-EVAR, in which the source of blood flow into the aneurysm sac could not be determined using conventional computed tomographic angiography. Consequently, dynamic volumetric computed tomographic angiography (DV-CTA) was employed, which clearly illustrated the site of origin of the endoleak. DV-CTA enables accurate endoleak characterization following f-EVAR, with excellent conspicuity of the source of blood flow into the aneurysm sac.

Total percutaneous aortic repair: midterm outcomes.

The purpose of this study was to examine the immediate and midterm outcomes of percutaneous endovascular repair of thoracic and abdominal aortic pathology. Between December 2003 and June 2005, 21 patients (mean age: 60.4 +/- 17.1 years; 15 males, 6 females) underwent endovascular stent-graft insertion for thoracic (n = 13) or abdominal aortic (n = 8) pathology. Preprocedural computed tomographic angiography (CTA) was performed to assess the suitability of aorto-iliac and common femoral artery (CFA) anatomy, including the degree of CFA calcification, for total percutaneous aortic stent-graft repair. Percutaneous access was used for the introduction of 18- to 26-Fr delivery devices. A 'preclose' closure technique using two Perclose suture devices (Perclose A-T; Abbott Vascular) was used in all cases. Data were prospectively collected. Each CFA puncture site was assessed via clinical examination and CTA at 1, 6, and 12 months, followed by annual review thereafter. Minimum follow-up was 36 months. Outcome measures evaluated were rates of technical success, conversion to open surgical repair, complications, and late incidence of arterial stenosis at the site of Perclose suture deployment. A total of 58 Perclose devices were used to close 29 femoral arteriotomies. Outer diameters of stent-graft delivery devices used were 18 Fr (n = 5), 20 Fr (n = 3), 22 Fr (n = 4), 24 Fr (n = 15), and 26 Fr (n = 2). Percutaneous closure was successful in 96.6% (28/29) of arteriotomies. Conversion to surgical repair was required at one access site (3.4%). Mean follow-up was 50 +/- 8 months. No late complications were observed. By CT criteria, no patient developed a >50% reduction in CFA caliber at the site of Perclose deployment during the study period. In conclusion, percutaneous aortic stent-graft insertion can be safely performed, with a low risk of both immediate and midterm access-related complications.

Portal vein embolization using a nitinol plug (Amplatzer vascular plug) in combination with histoacryl glue and iodinized oil: adequate hypertrophy with a reduced risk of nontarget embolization.

The purpose of this study was to assess whether portal vein embolization (PVE) using a nitinol vascular plug in combination with histoacryl glue and iodinized oil minimizes the risk of nontarget embolization while obtaining good levels of future liver remnant (FLR) hypertrophy. Between November 2005 and August 2008, 16 patients (8 females, 8 males; mean age, 63 +/- 3.6 years), each with a small FLR, underwent right ipsilateral transhepatic PVE prior to major hepatectomy. Proximal PVE was initially performed by placement of a nitinol vascular plug, followed by distal embolization using a mixture of histoacryl glue and iodinized oil. Pre- and 6 weeks postprocedural FLR volumes were calculated using computed tomographic imaging. Selection for surgery required an FLR of 0.5% of the patient's body mass. Clinical course and outcome of surgical resection for all patients were recorded. At surgery, the ease of hepatectomy was subjectively assessed in comparison to previous experience following PVE with alternative embolic agents. PVE was successful in all patients. Mean procedure time was 30.4 +/- 2.5 min. Mean absolute increase in FLR volume was 68.9% +/- 12.0% (p = 0.00005). There was no evidence of nontarget embolization during the procedure or on subsequent imaging. Nine patients proceeded to extended hepatectomy. Six patients demonstrated disease progression. One patient did not achieve sufficient hypertrophy in relation to body mass to undergo hepatic resection. At surgery, the hepatobiliary surgeons observed less periportal inflammation compared to previous experience with alternative embolic agents, facilitating dissection at extended hepatectomy. In conclusion, ipsilateral transhepatic PVE using a single nitinol plug in combination with histoacryl glue and iodinized oil simplifies the procedure, offering short procedural times with minimal risk of nontarget embolization. Excellent levels of FLR hypertrophy are achieved enabling safe extended hepatectomy.

Endovascular management of acute blunt traumatic thoracic aortic injury: a single center experience.

BACKGROUND: Traumatic injury of the thoracic aorta is a life-threatening complication in patients who sustain deceleration or crush injuries. The magnitude of force necessary to cause blunt thoracic aortic injury results in a high proportion of concomitant injuries, posing a significant challenge for prioritizing management. Open surgical mortality is increased in the presence of coexisting head, lung, and abdominal injuries. Spinal cord ischemia may occur following aortic cross-clamping and operative hypotension. Endovascular stent-graft placement offers a safe, effective, and timely treatment option. The aim of this study was to assess our single center experience of endovascular repair following acute blunt traumatic aortic injury. METHODS: Data from thirteen consecutive patients (mean age, 43.2 years; range, 16 to 84 years) with acute blunt traumatic aortic injury treated by endovascular stent-graft insertion between October 2001 and March 2007 was prospectively collected. Demographics, injury characteristics, technique, and complications were recorded. Follow-up data consisted of computed tomographic angiography and plain chest radiography at regular intervals. Mean and median follow-up after stent-graft implantation were 28.9 and 29 months, respectively. RESULTS: All patients underwent endovascular repair within a median of 9 hours from hospital presentation. Two patients underwent carotico-carotid bypass immediately prior to endovascular stenting during a single anesthetic. Stent-graft implantation was technically successful in all patients. No patient required conversion to open surgical repair of the acute blunt traumatic aortic injury. Procedure-related paraplegia was zero. Complications included proximal migration of initial stent-graft in one patient and iliac artery avulsion in another patient with consequent ilio-femoral bypass. The median hospital stay was 17 days. There were no in-hospital deaths. CONCLUSION: Endovascular repair is evolving as the procedure of choice for acute blunt traumatic aortic injury. Treatment of lesions that extend into the aortic arch is feasible with extra-anatomical bypass. In our study, endovascular repair of blunt traumatic aortic injury is a safe procedure with low morbidity and a mortality rate of zero.