Vertebroplasty versus sham procedure for painful acute osteoporotic vertebral compression fractures (VERTOS IV): randomised sham controlled clinical trial.

OBJECTIVE: To assess whether percutaneous vertebroplasty results in more pain relief than a sham procedure in patients with acute osteoporotic compression fractures of the vertebral body. DESIGN: Randomised, double blind, sham controlled clinical trial. SETTING: Four community hospitals in the Netherlands, 2011-15. PARTICIPANTS: 180 participants requiring treatment for acute osteoporotic vertebral compression fractures were randomised to either vertebroplasty (n=91) or a sham procedure (n=89). INTERVENTIONS: Participants received local subcutaneous lidocaine (lignocaine) and bupivacaine at each pedicle. The vertebroplasty group also received cementation, which was simulated in the sham procedure group. MAIN OUTCOME MEASURES: Main outcome measure was mean reduction in visual analogue scale (VAS) scores at one day, one week, and one, three, six, and 12 months. Clinically significant pain relief was defined as a decrease of 1.5 points in VAS scores from baseline. Secondary outcome measures were the differences between groups for changes in the quality of life for osteoporosis and Roland-Morris disability questionnaire scores during 12 months' follow-up. RESULTS: The mean reduction in VAS score was statistically significant in the vertebroplasty and sham procedure groups at all follow-up points after the procedure compared with baseline. The mean difference in VAS scores between groups was 0.20 (95% confidence interval -0.53 to 0.94) at baseline, -0.43 (-1.17 to 0.31) at one day, -0.11 (-0.85 to 0.63) at one week, 0.41 (-0.33 to 1.15) at one month, 0.21 (-0.54 to 0.96) at three months, 0.39 (-0.37 to 1.15) at six months, and 0.45 (-0.37 to 1.24) at 12 months. These changes in VAS scores did not, however, differ statistically significantly between the groups during 12 months' follow-up. The results for secondary outcomes were not statistically significant. Use of analgesics (non-opioids, weak opioids, strong opioids) decreased statistically significantly in both groups at all time points, with no statistically significant differences between groups. Two adverse events occurred in the vertebroplasty group: one respiratory insufficiency and one vasovagal reaction. CONCLUSIONS: Percutaneous vertebroplasty did not result in statistically significantly greater pain relief than a sham procedure during 12 months' follow-up among patients with acute osteoporotic vertebral compression fractures. TRIAL REGISTRATION: ClinicalTrials.gov NCT01200277.

Prognostic value of cardiovascular MR imaging biomarkers on outcome in peripheral arterial disease: a 6-year follow-up pilot study.

The objective of this pilot study was to explore the prognostic value of outcome of cardiovascular magnetic resonance (MR) imaging biomarkers in patients with symptomatic peripheral arterial disease (PAD) in comparison with traditional risk factors. Forty-two consecutive patients (mean age 64 ± 11 years, 22 men) referred for contrast-enhanced MR angiography (CE-MRA) were included. At baseline a comprehensive cardiovascular MRI examination was performed: CE-MRA of the infra-renal aorta and run-off vessels, carotid vessel wall imaging, cardiac cine imaging and aortic pulse wave velocity (PWV) assessment. Patients were categorized for outcome at 72 ± 5 months follow-up. One patient was lost to follow-up. Over 6 years, six patients had died (mortality rate 14.6 %), six patients (14.6 %) had experienced a cardiac event and three patients (7.3 %) a cerebral event. The mean MRA stenosis class (i.e., average stenosis severity visually scored over 27 standardized segments) was a significant independent predictor for all-cause mortality (beta 3.0 ± standard error 1.3, p = 0.02). Descending aorta PWV, age and diabetes mellitus were interrelated with stenosis severity but none of these were significant independent predictors. For cardiac morbidity, left ventricular ejection fraction (LVEF) and mean MRA stenosis class were associated, but only LVEF was a significant independent predictor (beta -0.14 ± 0.05, p = 0.005). Diabetes mellitus was a significant independent predictor for cerebral morbidity (beta 2.8 ± 1.3, p = 0.03). Significant independent predictors for outcome in PAD are mean MRA stenosis class for all-cause mortality, LVEF for cardiac morbidity and diabetes mellitus for cerebral morbidity.

Time to Reperfusion and Treatment Effect for Acute Ischemic Stroke: A Randomized Clinical Trial.

IMPORTANCE: Intra-arterial treatment (IAT) for acute ischemic stroke caused by intracranial arterial occlusion leads to improved functional outcome in patients treated within 6 hours after onset. The influence of treatment delay on treatment effect is not yet known. OBJECTIVE: To evaluate the influence of time from stroke onset to the start of treatment and from stroke onset to reperfusion on the effect of IAT. DESIGN, SETTING, AND PARTICIPANTS: The Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) was a multicenter, randomized clinical open-label trial of IAT vs no IAT in 500 patients. The time to the start of treatment was defined as the time from onset of symptoms to groin puncture (TOG). The time from onset of treatment to reperfusion (TOR) was defined as the time to reopening the vessel occlusion or the end of the procedure in cases for which reperfusion was not achieved. Data were collected from December 3, 2010, to June 3, 2014, and analyzed (intention to treat) from July 1, 2014, to September 19, 2015. MAIN OUTCOMES AND MEASURES: Main outcome was the modified Rankin Scale (mRS) score for functional outcome (range, 0 [no symptoms] to 6 [death]). Multiple ordinal logistic regression analysis estimated the effect of treatment and tested for the interaction of time to randomization, TOG, and TOR with treatment. The effect of treatment as a risk difference on reaching independence (mRS score, 0-2) was computed as a function of TOG and TOR. Calculations were adjusted for age, National Institutes of Health Stroke Scale score, previous stroke, atrial fibrillation, diabetes mellitus, and intracranial arterial terminus occlusion. RESULTS: Among 500 patients (58% male; median age, 67 years), the median TOG was 260 (interquartile range [IQR], 210-311) minutes; median TOR, 340 (IQR, 274-395) minutes. An interaction between TOR and treatment (P = .04) existed, but not between TOG and treatment (P = .26). The adjusted risk difference (95% CI) was 25.9% (8.3%-44.4%) when reperfusion was reached at 3 hours, 18.8% (6.6%-32.6%) at 4 hours, and 6.7% (0.4%-14.5%) at 6 hours. CONCLUSION AND RELEVANCE: For every hour of reperfusion delay, the initially large benefit of IAT decreases; the absolute risk difference for a good outcome is reduced by 6% per hour of delay. Patients with acute ischemic stroke require immediate diagnostic workup and IAT in case of intracranial arterial vessel occlusion. TRIAL REGISTRATION: trialregister.nl Identifier: NTR1804.

A randomized trial of intraarterial treatment for acute ischemic stroke.

BACKGROUND: In patients with acute ischemic stroke caused by a proximal intracranial arterial occlusion, intraarterial treatment is highly effective for emergency revascularization. However, proof of a beneficial effect on functional outcome is lacking. METHODS: We randomly assigned eligible patients to either intraarterial treatment plus usual care or usual care alone. Eligible patients had a proximal arterial occlusion in the anterior cerebral circulation that was confirmed on vessel imaging and that could be treated intraarterially within 6 hours after symptom onset. The primary outcome was the modified Rankin scale score at 90 days; this categorical scale measures functional outcome, with scores ranging from 0 (no symptoms) to 6 (death). The treatment effect was estimated with ordinal logistic regression as a common odds ratio, adjusted for prespecified prognostic factors. The adjusted common odds ratio measured the likelihood that intraarterial treatment would lead to lower modified Rankin scores, as compared with usual care alone (shift analysis). RESULTS: We enrolled 500 patients at 16 medical centers in The Netherlands (233 assigned to intraarterial treatment and 267 to usual care alone). The mean age was 65 years (range, 23 to 96), and 445 patients (89.0%) were treated with intravenous alteplase before randomization. Retrievable stents were used in 190 of the 233 patients (81.5%) assigned to intraarterial treatment. The adjusted common odds ratio was 1.67 (95% confidence interval [CI], 1.21 to 2.30). There was an absolute difference of 13.5 percentage points (95% CI, 5.9 to 21.2) in the rate of functional independence (modified Rankin score, 0 to 2) in favor of the intervention (32.6% vs. 19.1%). There were no significant differences in mortality or the occurrence of symptomatic intracerebral hemorrhage. CONCLUSIONS: In patients with acute ischemic stroke caused by a proximal intracranial occlusion of the anterior circulation, intraarterial treatment administered within 6 hours after stroke onset was effective and safe. (Funded by the Dutch Heart Foundation and others; MR CLEAN Netherlands Trial Registry number, NTR1804, and Current Controlled Trials number, ISRCTN10888758.).

Peripheral arterial occlusive disease: 3.0-T versus 1.5-T MR angiography compared with digital subtraction angiography.

PURPOSE: To prospectively evaluate the diagnostic accuracy of 3-T versus 1.5-T contrast material-enhanced (CE) magnetic resonance (MR) angiography with high spatial resolution in patients who have peripheral arterial occlusive disease, with conventional digital subtraction angiography (DSA) serving as the reference standard. MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained. DSA and standardized single-injection, three-station, moving-table CE MR angiography, with similar acquisition protocols and contrast agent doses at 3 T and 1.5 T, were consecutively performed in 19 patients (13 men and six women; mean age ± standard deviation, 67 years ± 9). Stenosis was scored visually in 500 arterial segments (97.5% of all available) in consensus by two radiologists in a blinded manner (the radiologists were unaware of the field strength and prior DSA and MR angiographic results and used randomized analysis order). Contrast-to-noise ratio was determined in the vascular tree of both legs. Statistical significance in stenosis scoring was evaluated by using generalized estimating equations. Contrast-to-noise differences were evaluated with paired t tests. Agreement between MR angiography and DSA was evaluated by using Fleiss-Cohen κ statistics. RESULTS: Both 3-T and 1.5-T CE MR angiography showed similar excellent agreement with DSA regarding stenosis classification (κ = 0.96 and 0.93, respectively). All sensitivity and specificity values exceeded 90%. Mean contrast-to-noise ratio was 3.0-4.2 times higher at 3 T than at 1.5 T. CONCLUSION: Standardized single-injection, three-station, moving-table 3-T CE MR angiography is reliable for classification of stenosis in patients suspected of having peripheral arterial occlusive disease, and diagnostic performance was similar to that seen with 1.5-T MR angiography. There was a significantly increased contrast-to-noise ratio for identical contrast agent dose at 3-T MR angiography.

Malpractice claims following screening mammography in The Netherlands.

Although malpractice lawsuits are frequently related to a delayed breast cancer diagnosis in symptomatic patients, information on claims at European screening mammography programs is lacking. We determined the type and frequency of malpractice claims at a Dutch breast cancer screening region. We included all 85,274 women (351,009 screens) who underwent biennial screening mammography at a southern breast screening region in The Netherlands between 1997 and 2009. Two screening radiologists reviewed the screening mammograms of all screen detected cancers and interval cancers and determined whether the cancer had been missed at the previous screen or at the latest screen, respectively. We analyzed all correspondence between the screening organization, clinicians and screened women, and collected complaints and claims until September 2011. At review, 20.9% (308/1,475) of screen detected cancers and 24.3% (163/670) of interval cancers were considered to be missed at a previous screen. A total of 19 women (of which 2, 6 and 11 women had been screened between 1997 and 2001 (102,439 screens), 2001 and 2005 (114,740 screens) and 2005 and 2009 (133,830 screens), respectively) had contacted the screening organization for additional information about their screen detected cancer or interval cancer, but filed no claim. Three other women directly initiated an insurance claim for financial compensation of their interval cancer without previously having contacted the screening organization. We conclude that screening-related claims were rarely encountered, although many screen detected cancers and interval cancers had been missed at a previous screen. A small but increasing proportion of women sought additional information about their breast cancer from the screening organization.

[Effort thrombosis of the subclavian vein]. / Inspanningsgerelateerde trombose van de V. subclavia.

Three patients, 2 women aged 42 and 20 years and a 21-year-old man, presented with painful swelling of the upper extremity. The symptoms developed after activities involving repetitive, excessive use of the upper extremity. Duplex examination and venography showed thrombosis of the subclavian vein. This specific type of thrombosis is known as effort thrombosis or Paget-von Schroetter syndrome. It results from a narrowed thoracic outlet combined with repetitive strenuous use of the upper extremity. All three patients were first treated with thrombolytic therapy using urokinase delivered locally in the thrombus with a catheter. After the thrombus had resolved, a first rib resection was performed to decompress the thoracic outlet. Due to the remaining substantial stenosis and vessel wall irregularity, additional percutaneous transluminal angioplasty was performed. It is important to treat effort thrombosis immediately and adequately. Otherwise, it may lead to a postthrombotic syndrome, which can be severely disabling.

Vertebroplasty versus conservative treatment in acute osteoporotic vertebral compression fractures (Vertos II): an open-label randomised trial.

BACKGROUND: Percutaneous vertebroplasty is increasingly used for treatment of pain in patients with osteoporotic vertebral compression fractures, but the efficacy, cost-effectiveness, and safety of the procedure remain uncertain. We aimed to clarify whether vertebroplasty has additional value compared with optimum pain treatment in patients with acute vertebral fractures. METHODS: Patients were recruited to this open-label prospective randomised trial from the radiology departments of six hospitals in the Netherlands and Belgium. Patients were aged 50 years or older, had vertebral compression fractures on spine radiograph (minimum 15% height loss; level of fracture at Th5 or lower; bone oedema on MRI), with back pain for 6 weeks or less, and a visual analogue scale (VAS) score of 5 or more. Patients were randomly allocated to percutaneous vertebroplasty or conservative treatment by computer-generated randomisation codes with a block size of six. Masking was not possible for participants, physicians, and outcome assessors. The primary outcome was pain relief at 1 month and 1 year as measured by VAS score. Analysis was by intention to treat. This study is registered at ClinicalTrials.gov, number NCT00232466. FINDINGS: Between Oct 1, 2005, and June 30, 2008, we identified 431 patients who were eligible for randomisation. 229 (53%) patients had spontaneous pain relief during assessment, and 202 patients with persistent pain were randomly allocated to treatment (101 vertebroplasty, 101 conservative treatment). Vertebroplasty resulted in greater pain relief than did conservative treatment; difference in mean VAS score between baseline and 1 month was -5·2 (95% CI -5·88 to -4·72) after vertebroplasty and -2·7 (-3·22 to -1·98) after conservative treatment, and between baseline and 1 year was -5·7 (-6·22 to -4·98) after vertebroplasty and -3·7 (-4·35 to -3·05) after conservative treatment. The difference between groups in reduction of mean VAS score from baseline was 2·6 (95% CI 1·74-3·37, p<0·0001) at 1 month and 2·0 (1·13-2·80, p<0·0001) at 1 year. No serious complications or adverse events were reported. INTERPRETATION: In a subgroup of patients with acute osteoporotic vertebral compression fractures and persistent pain, percutaneous vertebroplasty is effective and safe. Pain relief after vertebroplasty is immediate, is sustained for at least a year, and is significantly greater than that achieved with conservative treatment, at an acceptable cost. FUNDING: ZonMw; COOK Medical.

A simulator for teaching transrectal ultrasound procedures: how useful and realistic is it?

INTRODUCTION: : We describe a new simulator for teaching transrectal ultrasound (TRUS) and present the results of a preliminary evaluation of the simulator's realism and usefulness for training. METHODS: : A simulator for abdominal ultrasound was adjusted by the developer to enable simulation of TRUS by providing an opening for inserting a dummy rectal probe. To enable TRUS simulation, data from ultrasound prostate imaging of eight real patients obtained with our regular ultrasound machine were transferred to the simulator by connecting the computer of the simulator to the ultrasound machine. These data were used to create images in the TRUS simulator. Residents and urologists used the simulator to perform TRUS in one of the eight patient cases and judged the simulator's realism and usefulness. RESULTS: : We were able to construct an initial urological module for the TRUS simulator. The images shown on the monitor of the simulator are quite realistic. The simulator can be used without difficulty to collect data, to create cases, and to perform TRUS. The absence of an option for prostate biopsy and the lack of tissue resistance were mentioned as two important shortcomings. Forty-seven participants rated the simulator's overall realism and usefulness for training purposes as 3.8 (standard deviation: 0.7) and 4.0 (standard deviation: 0.8) on a five-point Likert scale, respectively. CONCLUSIONS: : The simulator we describe can be used as a training tool for TRUS. It enables training with different patient cases and minimizes the burden to patients. Simulation of prostate biopsies should be added to increase the model's usefulness.

Multicenter randomized controlled trial of the costs and effects of noninvasive diagnostic imaging in patients with peripheral arterial disease: the DIPAD trial.

OBJECTIVE: The purpose of our study was to compare the costs and effects of three noninvasive imaging tests as the initial imaging test in the diagnostic workup of patients with peripheral arterial disease. MATERIALS AND METHODS: Of 984 patients assessed for eligibility, 514 patients with peripheral arterial disease were randomized to MR angiography (MRA) or duplex sonography in three hospitals and to MRA or CT angiography (CTA) in one hospital. The outcome measures included the clinical utility, functional patient outcomes, quality of life, and actual diagnostic and therapeutic costs related to the initial imaging test during 6 months of follow-up. RESULTS: With adjustment for potentially predictive baseline variables, the learning curve, and hospital setting, a significantly higher confidence and less additional imaging were found for MRA and CTA compared with duplex sonography. No statistically significant differences were found in improvement in functional patient outcomes and quality of life among the groups. The total costs were significantly higher for MRA and duplex sonography than for CTA. CONCLUSION: The results suggest that both CTA and MRA are clinically more useful than duplex sonography and that CTA leads to cost savings compared with both MRA and duplex sonography in the initial imaging evaluation of peripheral arterial disease.

Outpatient treatment of arterial inflow stenoses of dysfunctional hemodialysis access fistulas by retrograde venous access puncture and catheterization.

OBJECTIVE: To determine the feasibility of endovascular treatment of inflow stenoses in arteriovenous fistulae (AVFs) through retrograde venous access catheterization. METHODS: We included all 22 dysfunctional AVFs with arterial inflow stenoses at access imaging between January 2002 and September 2006. Following retrograde venous access puncture, an interventional radiologist intended to cross the arteriovenous anastomosis and advance a catheter into the aortic arch. After depiction of the complete vascular access tree, angioplasty and/or stent placement was aimed for stenoses with a >50% luminal diameter reduction at digital subtraction angiography (DSA). RESULTS: In one radiocephalic AVF, a catheter could not be positioned into the aortic arch after retrograde venous access puncture. DSA depicted 28 inflow stenoses in the remaining 21 patients (11 radiocephalic AVFs and 10 brachiocephalic AVFs). Clinical improvement was obtained in 18 out of 19 patients with a technically successful intervention (<30% residual stenosis after angioplasty or stent placement). Following endovascular therapy, access flow of 12 patients with a low flow access improved from 431 +/- 150 ml/min to 818 +/- 233 ml/min, and four patients with steal symptoms became symptom free. One nonmaturing fistula could be salvaged by angioplasty, and access cannulation problems were solved in another patient following angioplasty. Brachial artery stent placement did not reduce steal symptoms in one case, whereas two patients, in whom stent placement was not thought desirable, showed a >30% residual arterial stenosis after angioplasty. No complications were observed at DSA and endovascular intervention. CONCLUSION: Retrograde venous access puncture and catheterization, as an alternative to a potentially more hazardous brachial artery or more invasive femoral artery approach, should be considered for the visualization of the arterial inflow and endovascular treatment of inflow stenoses.

Drug-eluting and bare nitinol stents for the treatment of atherosclerotic lesions in the superficial femoral artery: long-term results from the SIROCCO trial.

PURPOSE: To review clinical outcomes of patients with chronic limb ischemia and TASC type C lesions treated with sirolimus-eluting versus bare SMART nitinol self-expanding stents. METHODS: Data were obtained from a randomized, multicenter, double-blinded study conducted in 2 phases. All 93 patients had chronic limb ischemia and superficial femoral artery (SFA) occlusions or stenoses (average lesion length 8.3 cm). In total, 47 patients (31 men; mean age 66.3+/-9.1 years, range 50-84) received the sirolimus-eluting SMART stent and 46 patients (36 men; mean age 65.9 +/-10.8 years, range 38-83) received a bare SMART nitinol stent. Both groups were followed for a mean 24 months. RESULTS: Both the sirolimus-eluting and the bare SMART stents were effective in revascularizing the diseased SFA and in sustaining freedom from restenosis. For both types of stents, improvements in ankle-brachial indices (ABI) and symptoms of claudication were maintained over 24 months (median 24-month ABI 0.96 for the sirolimus group versus 0.87 for the bare stent group, p>0.05). At 24 months, the restenosis rate in the sirolimus group was 22.9% versus 21.1% in the bare stent group (p>0.05). The cumulative in-stent restenosis rates according to duplex ultrasound were 4.7%, 9.0%, 15.6%, and 21.9%, respectively, at 6, 9, 18, and 24 months; the rates did not differ significantly between the treatment groups. The TLR rate for the sirolimus group was 6% and for the bare stent group 13%; the TVR rates were somewhat higher: 13% and 22%, respectively. Mortality rates did not differ significantly between the groups. CONCLUSION: These data demonstrate that the sirolimus-eluting and the bare SMART stent are effective, safe, and free from restenosis in a majority of patients for up to 24 months. Because the restenosis rate in the bare stent group is unexpectedly low, no significant difference could be found between the sirolimus-eluting and the bare SMART stents.

Inflow stenoses in dysfunctional hemodialysis access fistulae and grafts.

BACKGROUND: The aim of the study is to prospectively determine the incidence of inflow stenoses in dysfunctional hemodialysis access arteriovenous fistulae (AVFs) and grafts (AVGs). METHODS: Contrast-enhanced magnetic resonance angiography (CE-MRA) was performed of 66 dysfunctional AVFs and 35 AVGs in 56 men and 45 women (mean age, 62 years; age range, 31 to 86 years). Complete inflow (from the subclavian artery), shunt region, and complete outflow (including subclavian vein) were shown at CE-MRA. In addition to standard digital subtraction angiography (DSA) of the shunt region and outflow, DSA of the complete inflow was obtained through access catheterization of all cases in which CE-MRA showed an inflow stenosis. Vascular stenosis is defined as greater than 50% decrease in luminal diameter compared with an uninvolved vascular segment located adjacent to the stenosis. Endovascular intervention of stenoses was performed in connection with DSA. RESULTS: CE-MRA showed 19 arterial stenoses in 14 patients (14%). DSA confirmed 18 of these lesions in 13 patients and showed no additional inflow lesions. Of the 13 patients, 7 patients had arterial stenoses only and 6 patients had accompanying stenoses in the shunt region and/or outflow. Referral criteria for the 13 patients to undergo access evaluation had been decreased flow rates (9 patients), steal symptoms (2 patients), and insufficient access maturation (2 patients). Access flow of the 9 patients with a low-flow access improved from 477 +/- 74 mL/min to 825 +/- 199 mL/min after angioplasty. One patient with steal symptoms became symptom free after angioplasty. Endovascular intervention in 3 patients proved to be unsuccessful. CONCLUSION: Inflow stenoses are not uncommon in dysfunctional hemodialysis access shunts. We suggest that radiological evaluation comprise assessment of the complete arterial inflow.

Stenosis detection in failing hemodialysis access fistulas and grafts: comparison of color Doppler ultrasonography, contrast-enhanced magnetic resonance angiography, and digital subtraction angiography.

OBJECTIVE: Several imaging modalities are available for the evaluation of dysfunctional hemodialysis shunts. Color Doppler ultrasonography (CDUS) and digital subtraction angiography (DSA) are most widely used for the detection of access stenoses, and contrast-enhanced magnetic resonance angiography (CE-MRA) of shunts has recently been introduced. To date, no study has compared the value of these three modalities for stenosis detection in dysfunctional shunts. We prospectively compared CDUS and CE-MRA with DSA for the detection of significant (> or = 50%) stenoses in failing dialysis accesses, and we determined whether the interventionalist would benefit from CDUS performed before DSA and endovascular intervention. METHODS: CDUS, CE-MRA, and DSA were performed of 49 dysfunctional hemodialysis arteriovenous fistulas and 32 grafts. The vascular tree of the accesses was divided into three to eight segments depending on the access type (arteriovenous fistula or arteriovenous graft) and the length of venous outflow. CDUS was performed and assessed by a vascular technician, whereas CE-MRA and DSA were interpreted by two magnetic resonance radiologists and two interventional radiologists, respectively. All readers were blinded to information from each other and from other studies. DSA was used as reference standard for stenosis detection. RESULTS: DSA detected 111 significant (> or = 50%) stenoses in 433 vascular segments. Sensitivity and specificity of CDUS for the detection of significant stenosed vessel segments were 91% (95% CI, 84%-95%) and 97% (95% CI, 94%-98%), respectively. We found a positive predictive value of 91% (95% CI, 84%-95%) and a negative predictive value of 97% (95% CI, 94%-98%). The sensitivity, specificity, positive predictive value, and negative predictive value of MRA were 96% (95% CI, 90%-98%), 98% (95% CI, 96%-99%), 94% (95% CI, 88%-97%), and 98% (95% CI, 96%-99%), respectively. CDUS and CE-MRA depicted respectively three and four significant stenoses in six nondiagnostic DSA segments. The interventionalist would have chosen an alternative cannulation site in 38% of patients if the CDUS results had been available. CONCLUSIONS: We suggest that CDUS be used as initial imaging modality of dysfunctional shunts, but complete access should be depicted at DSA and angioplasty to detect all significant stenoses eligible for intervention. CE-MRA should be considered only if DSA is inconclusive.

Sirolimus-eluting versus bare nitinol stent for obstructive superficial femoral artery disease: the SIROCCO II trial.

PURPOSE: To investigate further the safety and efficacy of the sirolimus-eluting S. M.A.R.T. Nitinol Self-expanding Stent by comparison with a bare stent in superficial femoral artery (SFA) obstructions. MATERIALS AND METHODS: This randomized, double-blind study involved 57 patients (29 in the sirolimus-eluting stent group and 28 in the bare stent group) with chronic limb ischemia and SFA occlusions (66.7%) or stenoses (average lesion length, 81.5 mm +/- 41.2). Stent implantation followed standard interventional techniques and a maximum of two stents could be implanted. The primary endpoint was the in-stent mean lumen diameter at 6 months as determined by quantitative angiography. RESULTS: Both stent types were effective in revascularizing the diseased SFA and allowing sustained patency for at least 6 months. There was no statistically significant difference between treatment groups in the in-stent mean lumen diameter at 6 months (4.94 mm +/- 0.69 and 4.76 mm +/- 0.54 mm for sirolimus-eluting and bare stent groups, respectively; P = .31). Although the diameter of the target lesion tended to be larger and percent stenosis tended to be lower with the sirolimus-eluting stent, there were no statistically significant differences between treatments in terms of any of the variables. The mean late loss values were 0.38 mm +/- 0.64 and 0.68 mm +/- 0.97 for the sirolimus-eluting stent group and the bare stent group, respectively (P = .20). The binary restenosis rates, with a cutoff of 50% at 6 months, were zero in the sirolimus-eluting stent group and 7.7% in the bare stent group (P = .49). Clinical outcomes matched angiographic outcomes with improvements in ankle-brachial index and symptoms of claudication. There was no significant difference between treatments in terms of adverse events. CONCLUSION: Although there is a trend for greater efficacy in the sirolimus-eluting stent group, there were no statistically significant differences in any of the variables.

Stenosis detection with MR angiography and digital subtraction angiography in dysfunctional hemodialysis access fistulas and grafts.

PURPOSE: To prospectively assess three-dimensional contrast material-enhanced magnetic resonance (MR) angiography for stenosis depiction in malfunctioning hemodialysis arteriovenous fistulas (AVFs) and grafts (AVGs), as compared with digital subtraction angiography (DSA). MATERIALS AND METHODS: Ethical review board approval and written informed consent were obtained. MR angiography and DSA were performed in 51 dysfunctional hemodialysis fistulas and grafts in 48 consecutive patients. Vascular tree of accesses was divided into between three and eight segments depending on access type (AVF or AVG) and length of venous outflow. Images obtained with MR and DSA were interpreted by two MR radiologists and two interventional radiologists, respectively, who were blinded to information from each other and other studies. DSA was reference standard for stenosis detection. Sensitivity, specificity, and predictive values with 95% confidence intervals (CIs) of contrast-enhanced MR in detection of vascular segments containing hemodynamically significant (> or =50%) stenosis were calculated. Linear-weighted kappa statistic was calculated for contrast-enhanced MR and DSA to determine interobserver agreement regarding stenosis detection. RESULTS: A total of 282 vascular segments were evaluated. Contrast-enhanced MR depicted three false-positive stenoses and all but two of 70 significant stenoses depicted with DSA. Sensitivity, specificity, and positive and negative predictive values of MR in detection of vessel segments with significant stenoses were 97% (95% CI: 90%, 99%), 99% (95% CI: 96%, 100%), 96% (95% CI: 88%, 99%), and 99% (95% CI: 97%, 100%), respectively. MR demonstrated significant stenosis in four of five nondiagnostic DSA segments, whereas DSA showed no significant stenosis in four nondiagnostic MR segments. Linear-weighted kappa statistic for interobserver agreement regarding stenosis detection was 0.92 (95% CI: 0.89, 0.95) for MR and 0.95 (95% CI: 0.92, 0.97) for DSA. CONCLUSION: MR angiography depicts stenoses in dysfunctional hemodialysis accesses but has limited clinical value as result of current inability to perform MR-guided access interventions after stenosis detection. MR of dysfunctional access should be considered only if nondiagnostic vascular segment is present at DSA.

Peripheral arterial disease: sensitivity-encoded multiposition MR angiography compared with intraarterial angiography and conventional multiposition MR angiography.

A sensitivity-encoded magnetic resonance (MR) angiography protocol was developed in which imaging times in the pelvic and upper-leg positions were reduced and isotropic submillimeter voxel volumes were acquired in the lower-leg position. To achieve this, sensitivity encoding and random central-k-space segmentation in a centric filling order were applied. Results with this technique were compared with those with midstream aortic digital subtraction angiography (DSA) (as the reference standard) and conventional MR angiography in 15 patients with peripheral vascular disease. The results show that sensitivity-encoded MR angiography demonstrates increased diagnostic accuracy in comparison to that with conventional MR angiography and depicts more open infragenual arterial segments compared with both midstream aortic DSA and conventional MR angiography.

Sirolimus-eluting stents for the treatment of obstructive superficial femoral artery disease: six-month results.

BACKGROUND: Stent implantation for obstructive femoropopliteal artery disease has been associated with poor long-term outcomes. This study evaluated the effectiveness of shape memory alloy recoverable technology (SMART) nitinol self-expanding stents coated with a polymer impregnated with sirolimus (rapamycin) versus uncoated SMART Stents in superficial femoral artery obstructions. METHODS AND RESULTS: Thirty-six patients were recruited for this double-blind, randomized, prospective trial. All patients had chronic limb ischemia and femoral artery occlusions (57%) or stenoses (average lesion length, 85 +/- 57 mm). Patients were eligible for randomization after successful guidewire passage across the lesion. Eighteen patients received sirolimus-eluting SMART Stents and 18 patients received uncoated SMART Stents. The primary end point of the study was the in-stent mean percent diameter stenosis, as measured by quantitative angiography at 6 months. The instent mean percent diameter stenosis was 22.6% in the sirolimus-eluting stent group versus 30.9% in the uncoated stent group (P = 0.294). The in-stent mean lumen diameter was significantly larger in the sirolimus-eluting stent group (4.95 mm versus 4.31 mm in the uncoated stent group; P = 0.047). No serious adverse events (death or prolonged hospitalization) were reported. CONCLUSIONS: The use of sirolimus-eluting SMART Stents for superficial femoral artery occlusion is feasible, with a trend toward reducing late loss compared with uncoated stents. The coated stent also proved to be safe and was not associated with any serious adverse events.

Failing hemodialysis access grafts: evaluation of complete vascular tree with 3D contrast-enhanced MR angiography with high spatial resolution: initial results in 10 patients.

Ten patients with failing hemodialysis access underwent contrast material-enhanced magnetic resonance (MR) angiography within 7 days before digital subtraction angiography (DSA). MR angiography was performed at 1.5 T by using a multistation multiinjection three-dimensional technique, and contrast material was injected via intravenous cannula. In all patients, MR angiographic images displayed the complete arterial inflow tract from the subclavian artery and access proper. The complete venous outflow tract up to the superior caval vein could be evaluated in all but one patient. DSA showed hemodynamically significant stenoses in 13 segments. MR angiography depicted all 13 stenoses and two false-positive findings, resulting in sensitivity of 100% and specificity of 94%.