CTA with fluoroscopy image fusion guidance in endovascular complex aortic aneurysm repair.

OBJECTIVES: To evaluate the effect of intraoperative guidance by means of live fluoroscopy image fusion with computed tomography angiography (CTA) on iodinated contrast material volume, procedure time, and fluoroscopy time in endovascular thoraco-abdominal aortic repair. METHODS: CTA with fluoroscopy image fusion road-mapping was prospectively evaluated in patients with complex aortic aneurysms who underwent fenestrated and/or branched endovascular repair (FEVAR/BEVAR). Total iodinated contrast material volume, overall procedure time, and fluoroscopy time were compared between the fusion group (n = 31) and case controls (n = 31). Reasons for potential fusion image inaccuracy were analyzed. RESULTS: Fusion imaging was feasible in all patients. Fusion image road-mapping was used for navigation and positioning of the devices and catheter guidance during access to target vessels. Iodinated contrast material volume and procedure time were significantly lower in the fusion group than in case controls (159 mL [95% CI 132-186 mL] vs. 199 mL [95% CI 170-229 mL], p = .037 and 5.2 hours [95% CI 4.5-5.9 hours] vs. 6.3 hours (95% CI 5.4-7.2 hours), p = .022). No significant differences in fluoroscopy time were observed (p = .38). Respiration-related vessel displacement, vessel elongation, and displacement by stiff devices as well as patient movement were identified as reasons for fusion image inaccuracy. CONCLUSION: Image fusion guidance provides added value in complex endovascular interventions. The technology significantly reduces iodinated contrast material dose and procedure time.

Coronary artery-bronchial artery fistulas: report of two Dutch cases with a review of the literature.

BACKGROUND: Coronary bronchial artery fistulas (CBFs) are rare anomalies, which may be isolated or associated with other disorders. MATERIALS AND METHODS: Two adult patients with CBFs are described and a PubMed search was performed using the keywords "coronary bronchial artery fistulas" in the period from 2008 to 2013. RESULTS: Twenty-seven reviewed subjects resulting in a total of 31 fistulas were collected. Asymptomatic presentation was reported in 5 subjects (19 %), chest pain (n = 17) was frequently present followed by haemoptysis (n = 7) and dyspnoea (n = 5). Concomitant disorders were bronchiectasis (44 %), diabetes (33 %) and hypertension (28 %). Multimodality and single-modality diagnostic strategies were applied in 56 % and 44 %, respectively. The origin of the CBFs was the left circumflex artery in 61 %, the right coronary artery in 36 % and the left anterior descending artery in 3 %. Management was conservative (22 %), surgical ligation (11 %), percutaneous transcatheter embolisation (30 %), awaiting lung transplantation (7 %) or not reported (30 %). CONCLUSIONS: CBFs may remain clinically silent, or present with chest pain or haemoptysis. CBFs are commonly associated with bronchiectasis and usually require a multimodality approach to be diagnosed. Several treatment strategies are available. This report presents two adult cases with CBFs and a review of the literature.

Plasma levels of matrix metalloproteinase-9: a possible diagnostic marker of successful endovascular aneurysm repair.

OBJECTIVE: The aim of the study was evaluating the diagnostic value of plasma matrix metalloproteinase- (MMP)-2 and -9 and tissue inhibitor of MMP-1 (TIMP-1) for endoleak detection after endovascular aneurysm repair (EVAR). REPORT: Consecutive EVAR patients (n = 17) with endoleak and matched controls without endoleak (n = 20) were prospectively enrolled. Increased levels of MMP-9 were observed in patients with endoleak (P < 0.001). Regression analysis showed no significant influence of age, sex or abdominal aortic aneurysm (AAA) size. The receiver operating characteristic (ROC) curve of plasma MMP-9 levels showed that a cut-off value of 55.18 ng ml(-1) resulted in 100% sensitivity and 96% specificity with an AUC value of 0.988 (P < 0.001) to detect endoleak. CONCLUSIONS: Plasma MMP-9 levels appear to discriminate between patients with and without an endoleak with high sensitivity and specificity.

New diagnostic and treatment strategies in renal artery stenosis: a promising pursuit or disappointment foretold?

Clinical management of renal artery stenosis has seen a major shift, after randomised clinical trials have shown no group benefit of endovascular intervention relative to optimal medical control. However, the inclusion criteria of these trials have been criticised for focusing on a subset of patients with atherosclerotic renal artery stenosis where intervention was unlikely to be beneficial. Moreover, new imaging and computational techniques have become available, which have the potential to improve identification of patients that will respond to interventional treatment. This review addresses the challenges associated with clinical decision making in patients with renal artery stenosis. Opportunities for novel diagnostic techniques to improve patient selection are discussed, along with ongoing Dutch studies and network initiatives that investigate these strategies.

[Peripheral artery disease: clinical and cost comparison between duplex ultrasonography and contrast-enhanced magnetic resonance angiography--a multicenter randomized trial]. / De kosten en de effecten van magnetischeresonantieangiografie en duplexechografie bij patiënten met perifeer arterieel vaatlijden: een multicentrische gerandomiseerde studie.

OBJECTIVE: To determine the clinical and economic consequences of replacing duplex ultrasonography (DUS) by contrast-enhanced magnetic resonance angiography (CE-MRA) for the initial diagnostic work-up of patients with peripheral artery disease (PAD). DESIGN: Randomised multicentre study. METHOD: In the period from January 2002 to August 2003, consecutive patients with PAD were randomly assigned to CE-MRA or DUS. The primary outcome measure was the costs. Secondary outcome measures included the confidence with which the specialist could take a therapeutic decision on the basis of the imaging study, the change in disease severity, and the change in quality of life (QOL) assessed during 6 months of follow-up. In addition, all costs of imaging, therapeutic interventions and outpatient visits were calculated. RESULTS: After 6 months of follow-up the data on 352 patients were analysed. Use of CE-MRA reduced the number of additional vascular-imaging procedures by 42% ((69-40)/69) and the specialists felt more confident about their therapeutic decisions. The diagnostic costs of all imaging studies taken together were Euro 167,- higher, on average, in the CE-MRA group (p < 0.001). However, after 6 months of follow-up, no statistically significant differences were found between the two groups with regard to the change in disease severity, the QOL, or the total costs (p > 0.05). CONCLUSION: Based on these findings, a specialist that replaces DUS by CE-MRA will feel more confident about taking a therapeutic decision and will feel less need for additional imaging. However, the diagnostic costs were higher with CE-MRA.

Safety and long-term effects of renal denervation: Rationale and design of the Dutch registry.

BACKGROUND: Percutaneous renal denervation (RDN) has recently been introduced as a treatment for therapy-resistant hypertension. Also, it has been suggested that RDN may be beneficial for other conditions characterised by increased sympathetic nerve activity. There are still many uncertainties with regard to efficacy, safety, predictors for success and long-term effects. To answer these important questions, we initiated a Dutch RDN registry aiming to collect data from all RDN procedures performed in the Netherlands. METHODS: The Dutch RDN registry is an ongoing investigator-initiated, prospective, multicentre cohort study. Twenty-six Dutch hospitals agreed to participate in this registry. All patients who undergo RDN, regardless of the clinical indication or device that is used, will be included. Data are currently being collected on eligibility and screening, treatment and follow-up. RESULTS: Procedures have been performed since August 2010. At present, data from 306 patients have been entered into the database. The main indication for RDN was hypertension (n = 302, 99%). Patients had a mean office blood pressure of 177/100 (±29/16) mmHg with a median use of three (range 0-8) blood pressure lowering drugs. Mean 24-hour blood pressure before RDN was 157/93 (±18/13) mmHg. RDN was performed with different devices, with the Simplicity™ catheter currently used most frequently. CONCLUSION: Here we report on the rationale and design of the Dutch RDN registry. Enrolment in this investigator-initiated study is ongoing. We present baseline characteristics of the first 306 participants.

Contemporary management of the demanding infra-renal neck in abdominal aortic aneurysm repair.

Proximal infrarenal neck anatomy is a crucial factor in determining outcome of abdominal aortic aneurysm (AAA) repair. Unfavorable or demanding infrarenal neck anatomy significantly increases the complexity of both standard endovascular and open repair resulting in increased rates of morbidity and mortality. While technological improvements and expanding institutional experience have resulted in an increased proportion of patients with an AAA with unfavorable infrarenal neck treated by (fenestrated) endovascular techniques, open repair has also remained a valid technique. The purpose of this manuscript was to describe the wide array of endovascular and open techniques in use to treat patients with an AAA with a demanding infrarenal neck and discuss their results and indications.

Strategies to prevent spinal cord ischemia in thoracoabdominal aortic aneurysm repair.

Spinal cord ischemia (SCI) after thoracic and thoracoabdominal aortic aneurysm repair is a devastating complication, which happens after both open and endovascular repair. Incidence of SCI varies widely in the literature. Many factors during preoperative, operative and postoperative phases influence this incidence. The purpose of this article was to provide an overview on all factors influencing SCI and to report on the evidence in the literature about how to prevent SCI.

Hemodynamic significance of collateral blood flow in chronic venous obstruction.

INTRODUCTION: Complaints related to the post-thrombotic syndrome do not always correlate well with the extent of post-thrombotic changes on diagnostic imaging. One explanation might be a difference in development of collateral blood flow. The aim of this study is to investigate the hemodynamic effect of collateralisation in deep venous obstruction. METHODOLOGY: Resting intravenous pressure of the common femoral vein was measured bilaterally in the supine position of patients with unilateral iliofemoral post-thrombotic obstruction. In addition, pressure in control limbs was also measured in the common femoral vein after sudden balloon occlusion in the external iliac vein. RESULTS: Fourteen patients (median age 42 years, 12 female) were tested. In eleven limbs post-thrombotic disease extended below the femoral confluence. Median common femoral vein pressure was 17.0 mmHg in diseased limbs compared to 12.8 mmHg in controls (p = 0.001) and 23.5 mmHg in controls after sudden balloon occlusion (p = 0.009). Results remained significant after correcting for non-occlusive post-thrombotic disease. CONCLUSION: This study shows that common femoral vein pressure is increased in post-thrombotic iliofemoral deep venous obstruction, though not as much as after sudden balloon occlusion. The latter difference could explain the importance of collateralisation in deep venous obstructive disease and the discrepancy between complaints and anatomical changes; notwithstanding, the presence of collaterals does not eliminate the need for treatment.

Interpretation of renal angiography by radiologists.

OBJECTIVE: Different radiologists may show considerable variation in their interpretation of renal angiograms. We therefore wished to establish the reliability of their interpretation. DESIGN: Assessment of the intra- and inter-observer agreement of the interpretation of renal angiograms. SETTING: Tertiary referral university hospital. PATIENTS: Hypertensive patients suspected of renovascular hypertension on clinical grounds or on the basis of renography. INTERVENTIONS: Patients were prospectively selected to undergo a renal angiography via the femoral approach. MAIN OUTCOME MEASURES: Intra- and inter-observer agreement of the degree and site of stenosis. RESULTS: The difference between two estimates of the degree of stenosis ranged from 0 to 65% for the individual readers and from 0 to 75% between two readers. When the site of greatest stenosis was in the origin of the renal artery, the intra-observer agreement kappa ranged from 0.54-0.71, the inter-observer agreement across multiple readers being 0.43. In a post hoc analysis using two different cut-off points of stenosis (50 or 70%), the intra- and inter-observer agreement was better at the 70% cut-off-point. In a subset of patients with stenosis and a renin ratio greater than 1.5, both the intra- and inter-observer agreement were much better than when all angiograms were considered. CONCLUSIONS: Assessment of the diagnostic performance of three experienced radiologists in their interpretation of renal artery angiograms indicates that the intra- and inter-observer agreement with respect to their estimates of the degree of stenosis and the site of greatest stenosis are rather poor but their diagnostic performance improves in patients with stenosis and a renin ratio greater than 1.5. There is a need for more objective assessment of renal artery lesions.

Renovascular disease in patients with hypertension: detection with duplex ultrasound.

The aim of this study was to evaluate the accuracy of duplex ultrasound for the diagnosis of renovascular disease in a cohort of hypertensive patients. In 78 patients suspected of renovascular hypertension on clinical grounds duplex ultrasound examination of the renal arteries was performed. Renal angiography was used as the standard of reference. Duplex ultrasound was inconclusive in 11 kidneys (7%). None of the supernumerary renal arteries was detected with duplex ultrasound. The overall prevalence of significant renovascular disease (> or =50% stenosis) was 20%. Based on the combination of parameters at thresholds commonly applied in current literature: ie PSV(max) >180 cm/sec and RAR >3.5 the overall sensitivity of duplex ultrasound for detection of haemodynamically significant renovascular disease was 50.0% with a specificity of 91.3% (PPV: 87.9%; NPV: 59.1). Lowering the thresholds for both parameters improved the test results at the cost of a significant increase of false positive examinations. In a population of hypertensive patients clinically suspected of renovascular hypertension, only limited results for duplex ultrasound could be acquired in the detection of renovascular disease. This result, in combination with the wide range of sensitivities and specificities published in international literature and the relatively large number of incomplete examinations does not support the general application of duplex ultrasound as a screening procedure for detection and assessment of renovascular disease.

The benefit of STent placement and blood pressure and lipid-lowering for the prevention of progression of renal dysfunction caused by Atherosclerotic ostial stenosis of the Renal artery. The STAR-study: rationale and study design.

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) is associated with progressive loss of renal function and is one of the most important causes of renal failure in the elderly. Current treatment includes restoration of the renal arterial lumen by endovascular stent placement. However, this treatment only affects damage caused by ARAS due to the stenosis and ensuing post-stenotic ischemia. ARAS patients have severe general vascular disease. Atherosclerosis and hypertension can also damage the kidney parenchyma causing renal failure. Medical treatment focuses on the latter. Lipid-lowering drugs (statins) could reduce renal failure progression and could reduce the overall high cardiovascular risk. The additional effect on preserving renal function of stent placement as compared to medical therapy alone is unknown. Therefore, the STAR-study aims to compare the effects of renal artery stent placement together with medication vs. medication alone on renal function in ARAS patients. METHOD: Patients with an ARAS of > or = 50% and renal failure (creatinine (Cr) clearance < 80 mL/min/1.73 m2) are randomly assigned to stent placement with medication or to medication alone. Medication consists of statins, anti-hypertensive drugs and antiplatelet therapy. Patients are followed for 2 yrs with extended follow-up to 5 yrs. The primary outcome of this study is a reduction in Cr clearance > 20% compared to baseline. This trial will include 140 patients.

The effect of equipment set up on patient radiation dose in conventional and CT angiography of the renal arteries.

Patient radiation dose in angiography of the renal arteries was assessed and optimized after installing new radiological equipment. In three separate studies (n=50, 25 and 20) patient exposure was monitored in detail. For the first study default factory settings were used, for the second the number of digital subtraction angiography (DSA) images was halved and the X-ray beam filtering during fluoroscopy was increased, and for the third study filtering during DSA was increased as well. Standard projections were derived and used in Monte Carlo simulations to derive dose conversion coefficients to calculate effective dose from the dose-area product (DAP). Dose conversion coefficients were also calculated for CT angiography (CTA). Using default factory settings on the new angiography system, DAP, number of images and effective dose were much higher than on the replaced unit. For the studies given above, DAP was reduced from 144 Gy cm(2) to 65 Gy cm(2) to 32 Gy cm(2), and effective dose from 22 mSv to 11 mSv to 9.1 mSv, respectively. Effective dose due to CTA was 5.2 mSv. It is concluded that modern angiography systems, resulting in high customer satisfaction, may readily cause much higher patient exposure than older systems. These doses may also be much higher than necessary. Optimization before putting such systems into use is absolutely essential. Internationally accepted recommendations for image quality and technique factors in angiography would be of great help.

Current topics on vascular access for hemodialysis.

Vascular access remains the lifeline for end-stage renal failure patients, which have been treated by chronic intermittent hemodialysis. Due to the steady increase in the number of patients with difficulties to create access, in particular in elderly with various comorbidities, the need for more insight and regulations have evolved into the publications of the American and European guidelines. From the latter it may be obvious that an adequate preoperative assessment followed by the creation of autogenous arteriovenous fistulas (AVFs) is far better and preferred to the implantation of grafts. Vascular access maintenance by monitoring and elective percutanuous or surgical revision is of utmost importance to keep the access site functional. Despite up-to-date measures for vascular access maintenance, various complications may treaten not only the access site but also quality and expectance of life. Thrombotic occlusion remains a major event, leading to permanent failure in 10% of AVFs and 20% of grafts each year. Interventional (percutaneous transluminal angioplasty and/or stent implantation) or surgical revision of thrombosed accesses have similar outcomes with a high rate of reinterventions. The elderly diabetic population with peripheral arteriosclerotic obstructive disease is in particular prone to angio-access induced handischemia. When not timely and properly treated this may lead to minor or major amputation, further hampering quality of life. Also, the enormous application in the past 2 decades of acute central venous lines has lead to a significant increase of central venous obstruction with concomittent morbidity and problems creating vascular access in the upper extremities. Radiological intervention in these cases is a primary option, leaving surgical reconstruction as a second best method. It may be obvious that creation and maintenance of hemodialysis vascular access has become an important and time-consuming speciality. Only an up-to-date multidisciplinary management with involvement of nurses, nephrologists, interventionalists and surgeons, will lead to the desired outcome.

[Contrast-enhanced magnetic resonance angiography]. / Contrastversterkte kernspinresonantieangiografie.

Contrast-enhanced magnetic resonance angiography (MRA) involves intravenous injection of a contrast medium that increases the signal intensity of blood by shortening its T1 value. With contrast-enhanced MRA the acquisition time is short (less than 40 s for the abdominal aorta and the iliac vessels) and the images obtained can be interpreted accurately. The contrast medium currently in use virtually never causes adverse effects and is not nephrotoxic. After obtaining a three-dimensional dataset projections can be made at will. In addition, the individual partitions should be evaluated. The postprocessing time is about 15 min per examination. Current clinical applications are diagnostic examination of (stenoses of) the aortic arch and its branches, the thoracic and abdominal aorta, the visceral vessels, the renal arteries and the peripheral arteries. The sensitivity and specificity of contrast-enhanced MRA in most studies amount to over 90%.

The current endovascular therapeutic spectrum for short neck and juxtarenal aneurysms.

Endovascular treatment of short neck infrarenal and juxtarenal abdominal aortic aneurysms (AAA) is feasible. Many different techniques have been used, including standard stent-grafts with or without adjuncts as endoanchors or chimney grafts, fenestrated stent-grafts or even newer concepts like the multilayer flow modulating stent. The purpose of this article was to describe the techniques, the indications and results of the various endovascular methods to treat short neck infrarenal and juxtarenal AAA.

Septocutaneous tensor fasciae latae perforator flap for breast reconstruction: radiological considerations and clinical cases.

INTRODUCTION: The deep inferior epigastric artery perforator (DIEP) flap is the first choice in autologous breast reconstruction; in cases when it cannot be used, alternative flaps are available. A radiological study and clinical cases using septocutaneous tensor fasciae latae (sc-TFL) flap for breast reconstruction are presented. MATERIALS: Magnetic resonance angiographies (MRAs) of 55 patients were evaluated. The pedicle and the perforators of the TFL were studied. Five consecutive sc-TFL flaps for breast reconstruction were performed. RESULTS: Thirty-seven MRA scans were included. There was a mean of 1.5 septocutaneous perforators per thigh. The mean pedicle length was 8.3 cm. Every perforator originated from a branch of the lateral circumflex femoral artery (LCFA). The LCFA originated from the arteria femoralis profunda in 89.2% of cases. In the vertical plane, the mean distance of the perforator from the antero-superior iliac spine was 8.7 cm. There were no major complications in the five sc-TFL performed. CONCLUSION: On MRA, the septocutaneous pedicle of the TFL perforator flap was consistently present. MR angiographic assessment of the septocutaneous branches was very helpful in the preoperative evaluation of our patients. Dissection of the sc-TFL can be performed in a supine position simultaneously with mastectomy and/or dissection of the mammary vessels. Finally, the donor-site scar can be hidden by underwear, giving minimal deformity. We recommend the sc-TFL flap as a good alternative to the DIEP flap for autologous breast reconstruction. Preoperative imaging is mandatory for correct planning of the flap.

Value of magnetic resonance venography and computed tomographic venography in lower extremity chronic venous disease.

For the treatment of chronic venous disease (CVD) of the lower extremity, identification of the underlying venous pathologies is essential. Traditionally, the pathologies to detect with imaging have been centred on insufficiency and reflux of the superficial, perforator and deep veins of the leg. More recently, stenosis and obstruction of the deep veins of the pelvis and abdomen (i.e. inferior vena cava, common and external iliac veins) have been identified as significant underlying pathologies in CVD. Accurate detection of stenotic and/or occlusive venous disease expands the treatment options for patients with CVD. In most cases, imaging of venous disease is performed with duplex ultrasound. In this article we discuss the existing evidence and potential value of computed tomographic venography and magnetic resonance venography to contribute in accurately identifying chronic venous disease, in particular chronic venous obstruction.

Spinal cord function monitoring during endovascular treatment of thoracoabdominal aneurysms: implications for staged procedures.

AIM: Spinal cord ischemia is a well-known complication in the treatment of thoracoabdominal aneurysms (TAAA). Despite the fact that endovascular treatment of TAAA is less invasive, spinal cord ischemia rate is not reduced if compared to open repair. METHODS: We report the results of our experience of spinal cord function monitoring by measuring motor evoked potentials (MEP) during endovascular treatment of TAAA type II and III. Depending on the level of the MEPs the decision is made whether to stage the procedure or not. We treated ten patients according to this protocol. RESULTS: In two patients, MEPs decreased 50% or more and procedures were staged. Both experienced no neurological complications after first and second procedure. No MEPs decrease was seen during the second procedures. One of the other eight patients had a temporary right lower leg pararesis. CONCLUSION: In conclusion we state that our first experience demonstrates the value of assessing spinal cord function during extensive endovascular TAAA repair with subsequent strategies to prevent paraplegia.