Effect of Intravenously Injected Iodinated Lipid Emulsions on the Liver

Iodinated lipid emulsions have been shown to have great potential as site specific contrast media for the liver and spleen. Because of unacceptable adverse reactions none of these emulsions has been adopted for clinical use. In an attempt to find an explanation for these adverse reactions we tested three iodinated lipid emulsions, EOE-13, AG 60.99 and AG 66.18. The following models were used: Computed tomography (CT) of the rabbit liver, in vivo microscopy and electron microscopy of the rat liver. The emulsions contained particles of different sizes and were used in varying doses. We found that the larger the emulsion particles, the more likely they were to be taken up by the Kupffer cells and thereby the higher the opacification of the liver achieved at CT. We also observed changes in the microcirculation of the liver when the emulsions were given in doses required to secure satisfactory opacification of the liver at CT. The main changes were 1) a marked increase in the size of the Kupffer cells, and 2) damage to the sinusoidal endothelium, both contributing to sinusoidal congestion. These changes strongly suggest activation of the macrophages and this in turn probably results in the release of toxic mediators. We suspect that the adverse reactions observed in patients when using iodinated lipid emulsions are due to these toxic mediators.

Clinical Trials with a New Iodinated Lipid Emulsion for Computed Tomography of the Liver

A new iodinated lipid emulsion, Intraiodol, for which animal studies have indicated better tolerance than for other iodinated lipid emulsions, was tested in 15 patients with malignant lesions, and in one patient with focal nodular hyperplasia. Repeated CT scans of the liver and spleen and blood tests were performed for 24 hours after intravenous injection of Intraiodol. The uptake of Intraiodol in the liver (peak mean 28.6 HU) was higher than in the spleen (peak mean 21.8 HU). The uptake of Intraiodol in malignant lesions was minimal (peak mean 2.8 HU). The detection rate of hepatic lesions was equal to or better than that achieved by US, CT, and/or CT angiography. However, liver uptake of Intraiodol was low in 2 patients with severe fatty infiltration. Intraiodol produced vascular enhancement up to one hour after injection since it was eliminated slowly from the circulation. The observed adverse reactions consisted of temporary metallic taste in 5 of the patients, fever and exacerbation of back pain in one patient, and transient thrombocytopenia in one patient. Alkaline phosphatase increased (17%, p<0.01) only at two hours, and erythrocyte count (6%, p<0.05) at 24 hours after injection. Our initial results indicate diagnostic advantages of Intraiodol without serious adverse reactions. Further clinical studies are required to confirm these findings.

Percutaneousc Gastrostomy

Fluoroscopic percutaneous gastrostomy for the purpose of nutrition was performed in 28 patients with the aid of a specially designed gastrostomy set. No major complications were reported. Exchange to Foley catheter was performed after 7 days and could be used without complications for the patients' remaining life span. In order to evaluate the formation of a gastrocutaneous tract, an experimental study with the same instruments as in clinical practice was performed in 13 rabbits. Within one week a gastrocutaneous tract was formed, which was possible to dilate for insertion of a balloon catheter of larger size. The described procedure is a simple and time-saving method for a percutaneous gastrostomy in debilitated patients with dysphagia.

Ultrasonography and Doppler Duplex Compared with Angiography in Follow-up of Mesocaval Shunt Patency

Thirty-four patients with portal hypertension of various etiologies were operated upon with an interposition mesocaval Goretex graft. During a period of 6 years 84 angiographic and ultrasonographic (US) examinations (53 B-mode, and 31 Doppler Duplex) were performed, with few exceptions within 3 days. Angiography served as the ‘gold standard’. Shunt patency was correctly interpreted as normal in B-mode US in 38 examinations. Shunt occlusion, definite or probable, was seen in 12 B-mode examinations, where angiography demonstrated occlusion in 6 and patency in the remaining 6 shunts. Shunt occlusion was not observed sonographically in one examination. US was technically inadequate on two occasions. Doppler Duplex showed shunt patency in all 31 examinations, which was correct according to angiography. Both B-mode US, in 6 out of 6 examinations, and Doppler Duplex, in 7 out of 9 examinations failed to reveal shunt stenosis. Five patients with abundant venous collaterals (in one case with aberrant vascular anatomy) were not possible to evaluate even after the introduction of Doppler Duplex, which otherwise facilitated the evaluation. We suggest that US including Doppler should be the primary modality for follow-up in patients with interposition mesocaval Goretex grafts.

Computed Tomography in the Diagnosis and Treatment of Mediastinal Abnormalities in Children

Thirty-one children with mediastinal abnormalities—14 malignant lymphomas, 4 other primary malignancies, one metastatic and 12 benign lesions—were examined one or several times using CT, which proved to be effective especially for cysts (5 patients), ductus arteriosus aneurysm (2 patients), and intrathoracic liver (one patient). It also supplied important diagnostic information regarding the extent of disease in malignant thymoma (one patient), in neurinoma (one patient), and in Hodgkin's lymphoma (5 patients). It was found to be useful in the monitoring of treatment of patients with lymphomas, in which a small residue, probably a fibrotic remnant, was invariably seen after completion of chemotherapy and irradiation. It was concluded that when the residue was enlarged, the possibility of relapse and even thymic hyperplasia should be considered. However, if CT was performed under general anaesthesia pseudo-widening of the anterior mediastinum could simulate recurrence. Surgical biopsy was found to be necessary in these cases because fine-needle aspiration biopsy was unsuccessful.

Laser Therapy and Insertion of Wallstents for Palliative Treatment of Esophageal Carcinoma

A combination of endoscopic laser therapy (ELT) and insertion of Wallstents is a good alternative therapy for palliation of esophageal carcinoma and was performed in 12 patients. The method allows repeated laser therapy and, if necessary, supplementary insertion of stents to maintain the patients' ability to swallow during their remaining lifespan.

Experimental Investigation of a New Iodinated Lipid Emulsion for Computed Tomography of the Liver

Iodinated lipid emulsions are highly efficient macrophage imaging agents. Nevertheless, none of them has been accepted for clinical use because of adverse reactions. We have tested a new iodinated lipid emulsion, Intraiodol. The size and surface properties of the particles of this emulsion are similar to those of Intralipid which in turn closely resemble the naturally occurring chylomicrons. Using computed tomography (CT) of the rabbit liver as well as vital microscopy and electron microscopy of the rat liver we found that Intraiodol has low efficiency as a liver-specific contrast medium because its particles are predominantly taken up by the hepatocytes and to a less extent by the Kupffer cells, as is Intralipid. The low efficiency of Intraiodol could be fully compensated by an increase in dosage without any significant effect on sinusoidal blood flow. This in turn suggests that the likelihood of release of toxic mediators (and thereby related adverse reactions from activated macrophages) is reduced. We believe that this new way of delivering iodinated lipid particles to the liver represents an important advance in the search for a non-toxic lipid emulsion for CT of the liver.

Endovascular Stent-Anchored Aortic Grafts: A Comparison between Self-Expanding and Balloon-Expandable Stents in Minipigs

Purpose:

To study endovascular graft attachment with self-expanding Gianturco Z-stents and balloon-expanded Palmaz stents and the effect of these devices on the renal ostia.

Methods:

Ten stent-grafts were constructed, 5 with Gianturco Z-stents and 5 with Palmaz stents. The endografts were implanted under fluoroscopic guidance into the abdominal aorta of 10 pigs so that the uncovered portion of the proximal stent extended over the renal artery orifices. Distal aortic blood pressure and flow were measured before and after graft placement and 1 hour postprocedure. The aorta was then exposed surgically, and the central portion of the stent-graft was inspected through an aortotomy to assess perigraft leakage.

Results:

Stent-graft implantation was accurate and hemostatic in all cases, despite longitudinal folding of the graft due to oversizing. However, transverse folds produced pressure gradients (> 15 mmHg) between the ends of the graft in two cases. In another case, a pressure gradient resulted from partial thrombosis of the graft. In two cases, renal artery occlusion and thrombosis occurred due to coverage by the graft material. In two other animals, one of the renal arteries was entirely uncovered by a stent. The remaining 16 renal arteries were covered by the proximal stent but not the graft, as intended. One (6.25%) of these arteries thrombosed, but the remainder were grossly patent when the animals were sacrificed at 1 hour.

Conclusions:

Both Palmaz and Gianturco Z-stents produced hemostatic endovascular graft attachment, even in the presence of moderate graft oversizing. The risk of acute renal artery occlusion from juxtarenal stenting does not appear to be prohibitive, but longer term observations are needed.

Abdominal Aortic Aneurysm Morphology in Candidates for Endovascular Repair Evaluated with Spiral Computed Tomography and Digital Subtraction Angiography

Purpose:

To analyze the morphology of abdominal aortic aneurysms (AAAs) and to study the usefulness of spiral computed tomography (CT) versus digital subtraction angiography (DSA) in the evaluation of patients for endovascular repair.

Methods:

Of 133 AAA patients (120 men, mean age 67 years, range 52 to 84) evaluated preoperatively with CT imaging, 77 endograft candidates (68 men) were also assessed with intra-arterial DSA. Arterial parameters were measured on axial CT scans and angiographic films for comparison.

Results:

Mean maximum AAA diameter was 58 ± 11 mm (range 39 to 95). Aneurysmal neck diameter was consistently smaller on DSA than on CT (20.7 ± 3.6 mm versus 23.0 ± 3.5 mm, p < 0.0001). The distance from the most distal renal artery to the aortic bifurcation was longer on angiography than on CT (mean difference 10.0 mm, p < 0.0001). There was a positive correlation between the maximum AAA diameter and the AAA length (r = 0.49, p < 0.0001) and an inverse relationship between the neck length and the neck diameter (r = −0.36, p < 0.0001). No correlation was found between the maximum AAA diameter and maximum iliac diameter, angulation, or length.

Conclusions:

AAA anatomy varies widely and independently of the aneurysm size. Therefore, the maximum size of the aneurysm is a poor predictor of whether or not an aneurysm is suitable for endovascular repair. The discrepancy between angiographic and axial CT measurements suggests that neither alone is sufficient as a preoperative imaging technique when evaluating a patient for an endovascular graft procedure.

Endovascular AAA Exclusion: Will Stents with Hooks and Barbs Prevent Stent-Graft Migration?

Purpose:

To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta.

Methods:

Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force.

Results:

The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p < 0.001. Both hooks and barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects.

Conclusions:

Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.

Abdominal Aortic Aneurysms: Experience with the Ivancev-Malmö Endovascular System for Aortomonoiliac Stent-Grafts

Purpose:

To describe a component-based aortomonoiliac stent-graft system and the first clinical results achieved with this device in endovascular abdominal aortic aneurysm (AAA) repair.

Methods:

From November 1993 to October 1996, 45 patients aged 60 to 86 years underwent endoluminal exclusion of true AAAs (median diameter 60 mm) involving the common iliac arteries (median diameter 16 mm right and 15 mm left) using unilimb stent-grafts deployed with the Ivancev-Malmö system.

Results:

Six immediate conversions occurred in the beginning of the series due to endografts that were too short. Complications, including 2 inadvertent renal artery occlusions, 7 kinked grafts, 6 iliac artery dissections, and 3 perioccluder leaks, were prominent features in the first 15 patients. Five patients died in the postoperative period, four of whom were nonsurgical candidates. There were five significant stent-graft migrations: one 3 weeks after surgery due to mechanical injury of the proximal stent and four after 1 year owing to continuous dilation of a wide proximal neck, stent-graft placement in a conical, thrombus-lined proximal neck, and two instances of proximal extension separation from the main graft. Translumbar aneurysm perfusion required embolization in 3 patients.

Conclusions:

Despite early complications associated with a learning curve, exclusion of large AAAs using unilimb stent-grafts is feasible. Strict inclusion criteria are necessary in order to improve mortality among nonsurgical candidates and minimize the risk for late migration.

Late Aortic Arch Perforation by Graft-Anchoring Stent: Complication of Endovascular Thoracic Aneurysm Exclusion

Purpose:

To describe a fatal case of late aortic perforation by an endograft-anchoring stent.

Methods and Results:

A 69-year-old woman presented 2 years after thoracoabdominal aneurysm repair with a 9-cm dilatation of the descending thoracic aorta proximal to the conventional aortic graft. A 38-mm Dacron graft with multiple Gianturco Z-stents sutured inside was placed transluminally across the aortic arch such that part of the uncovered portion of the proximal stent was partially across the left subclavian orifice. Four months later, the patient died from massive hemorrhage. Autopsy showed that the uncovered portion of the proximal stent had perforated the aortic arch.

Conclusions:

This case stresses the need for low-profile stent-grafts and smaller, more flexible introducer systems. Anchoring stents must be flexible, less traumatic, and strong enough to create a watertight seal even in tortuous vessels. To avoid aortic arch damage by thoracic stent-grafts, the proximal stent should be fully covered by the fabric.

The role of permissive hypotension in the management of ruptured abdominal aortic aneurysms

The aim of this review was to explore current literature pertaining to the use of permissive hypotension in the treatment of abdominal aortic aneurysms. A literature search using Metalib, a database search engine, provided at the Royal Free and University College of London (UCL) yielded articles using the keywords "permissive hypotension" and "hypotensive resuscitation" when linked to "abdominal aortic aneurysm" and "rupture". The articles studying permissive hypotension in animals and humans in trauma, and in patients with abdominal aortic aneurysm were reviewed. The result of this search was a large volume of experimental studies of trauma in animals giving satisfactory evidence of the physiological benefit of this concept of resuscitation in trauma. There were some randomized trials in humans in trauma suggesting benefit. The safety of permissive hypotension in patients with ruptured aortic aneurysms was documented and found to be widespread, but there were no randomized trials directly comparing this practice. Evidence from a prospective randomized study on the modality of treatment of ruptured aortic aneurysms suggest that the level of blood pressure is associated with the mortality and a prospective cohort study suggests that, using the complementary concept of "delayed volume resuscitation", the total volume of preoperative fluid resuscitation independent of the blood pressure is predictive of the risk of perioperative death in ruptured aortic aneurysms. To this end, recent clinical publications are now supportive of control of both the volume of preoperative fluid given and blood pressure in this group of patients but clinical studies are few.

Consensus Document of the International Union of Angiology (IUA)-2013. Current concept on the management of arterio-venous management

Arterio-venous malformations (AVMs) are congenital vascular malformations (CVMs) that result from birth defects involving the vessels of both arterial and venous origins, resulting in direct communications between the different size vessels or a meshwork of primitive reticular networks of dysplastic minute vessels which have failed to mature to become 'capillary' vessels termed "nidus". These lesions are defined by shunting of high velocity, low resistance flow from the arterial vasculature into the venous system in a variety of fistulous conditions. A systematic classification system developed by various groups of experts (Hamburg classification, ISSVA classification, Schobinger classification, angiographic classification of AVMs,) has resulted in a better understanding of the biology and natural history of these lesions and improved management of CVMs and AVMs. The Hamburg classification, based on the embryological differentiation between extratruncular and truncular type of lesions, allows the determination of the potential of progression and recurrence of these lesions. The majority of all AVMs are extra-truncular lesions with persistent proliferative potential, whereas truncular AVM lesions are exceedingly rare. Regardless of the type, AV shunting may ultimately result in significant anatomical, pathophysiological and hemodynamic consequences. Therefore, despite their relative rarity (10-20% of all CVMs), AVMs remain the most challenging and potentially limb or life-threatening form of vascular anomalies. The initial diagnosis and assessment may be facilitated by non- to minimally invasive investigations such as duplex ultrasound, magnetic resonance imaging (MRI), MR angiography (MRA), computerized tomography (CT) and CT angiography (CTA). Arteriography remains the diagnostic gold standard, and is required for planning subsequent treatment. A multidisciplinary team approach should be utilized to integrate surgical and non-surgical interventions for optimum care. Currently available treatments are associated with significant risk of complications and morbidity. However, an early aggressive approach to elimiate the nidus (if present) may be undertaken if the benefits exceed the risks. Trans-arterial coil embolization or ligation of feeding arteries where the nidus is left intact, are incorrect approaches and may result in proliferation of the lesion. Furthermore, such procedures would prevent future endovascular access to the lesions via the arterial route. Surgically inaccessible, infiltrating, extra-truncular AVMs can be treated with endovascular therapy as an independent modality. Among various embolo-sclerotherapy agents, ethanol sclerotherapy produces the best long term outcomes with minimum recurrence. However, this procedure requires extensive training and sufficient experience to minimize complications and associated morbidity. For the surgically accessible lesions, surgical resection may be the treatment of choice with a chance of optimal control. Preoperative sclerotherapy or embolization may supplement the subsequent surgical excision by reducing the morbidity (e.g. operative bleeding) and defining the lesion borders. Such a combined approach may provide an excellent potential for a curative result. Conclusion. AVMs are high flow congenital vascular malformations that may occur in any part of the body. The clinical presentation depends on the extent and size of the lesion and can range from an asymptomatic birthmark to congestive heart failure. Detailed investigations including duplex ultrasound, MRI/MRA and CT/CTA are required to develop an appropriate treatment plan. Appropriate management is best achieved via a multi-disciplinary approach and interventions should be undertaken by appropriately trained physicians.

Are there fewer complications with third generation endografts in endovascular aneurysm repair?

Endovascular aneurysm repair (EVAR) is widely accepted as a safe technique for treatment of aortic diseases since the concept was first pioneered by Volodos in 1986 and Parodi in 1991. Numerous registries have shown that this minimally invasive technique is associated with lower mortality when compared to open surgery in short and mid-term follow-up. The first pioneer devices had a high failure rate due to stent migration. This led to the creation of the first generation stent-grafts, which were associated with complications such as thrombosis of the limbs, graft migration and major endoleaks. The majority of these endostents are now withdrawn from the commercial market. However, these patients need lifelong surveillance because of a considerable risk of late complications. The materials used in the stent-graft vary with each manufacturer. Low porous fabric, suprarenal fixation and low profile devices led to the development of the second generation stent-grafts. The improvements with regards to the delivery systems, enabled reposition of the top-stent following deployment in some devices. The number of devices commercially available increased with the second generation. The third generation of stent-grafts, allowed treatment of complex aortic disease. Custom made solutions incorporate small openings, fenestrations for vessels involved in the aneurysmal disease and is already built in today's technology and available as CE marked devices. The device can be built with combinations of various branches and fenestrations in order to best accommodate the aortic anatomy of the patient. However, many issues remain with the development of this technology. There is a need for durable systems with less complicated deployment mechanics in order to be applied and more widespread. In conclusion, the third generation endografts in challenging anatomy has yielded encouraging results. With regards to short and midterm outcome and need for secondary interventions, evaluations shows comparable results with all devices performing well.

Fenestrated endovascular aneurysm repair

Background

Fenestrated endovascular aneurysm repair (FEVAR) is a technically challenging operation. The duration, blood loss, and risk of limb ischaemia, contrast-induced nephropathy and reperfusion injury are likely to be higher than after standard endovascular aneurysm repair (EVAR). Benefits of FEVAR over open repair may be less than those seen with standard infrarenal EVAR. This paper is a meta-analysis of observational studies of all published data for FEVAR, with the aim to highlight current issues around the evidence for the potential benefit of FEVAR.

Methods

A search was performed for studies describing FEVAR for juxtarenal abdominal aortic aneurysms. Small series of fewer than ten procedures and studies describing predominantly branched endografts or FEVAR for aortic dissection were excluded. Authors of included papers were contacted to eliminate patient duplication.

Results

Eleven studies were identified describing a total of 660 procedures. Definitions of aneurysm morphology were variable, and clear inclusion and exclusion criteria were not always documented. Double fenestrations were more common than triple or quadruple fenestrations. Target vessel perfusion rates ranged from 90·5 to 100 per cent. Eleven deaths occurred within 30 days, giving a 30-day proportional mortality rate of 2·0 per cent. Morbidity was poorly reported.

Conclusion

FEVAR for repair of suprarenal and juxtarenal aneurysms is a viable alternative to open repair. However, there is no level 1 evidence for FEVAR, and current evidence is weak with many unanswered questions.

Techniques for supra-aortic trunk preservation in thoracic endovascular aneurysm repair

Stent graft placement for aneurysmal disease of the aortic arch and proximal descending aorta is limited by the need to preserve flow to the supra-aortic trunks. Whilst extra-anatomical bypass and procedures combining open and endovascular arch repair are currently used in this setting, less invasive totally endovascular solutions have been described. These include in-situ fenestration of a thoracic stent graft using a retrograde approach from the target vessel to the lumen of the main device, to which it is connected by a smaller covered stent. Alternatively, so-called 'chimney' stents have been used, placing a parallel stent alongside the main device, connecting the aortic branch vessel with the native aortic lumen proximal to the seal zone of the main thoracic device. We review these techniques and discuss the merits and potential disadvantages of each procedure.

Mid-term outcome of endovascular revascularization for chronic mesenteric ischaemia

Background

This study aimed to assess mid-term outcome after endovascular revascularization of chronic occlusive mesenteric ischaemia (CMI) and to identify possible predictors of mortality.

Methods

Consecutive patients undergoing primary elective stenting for CMI between 1995 and 2007 were registered prospectively in a database. Patients with acute ischaemia were excluded. Retrospective case-note review and data analysis were performed.

Results

Forty-three patients (10 men) were treated for stable (n = 30) or exacerbated (n = 13) CMI. Their median (interquartile range (i.q.r.)) age was 70 (60–79) years. Revascularization was successful in 47 of 49 vessels. The superior mesenteric artery (SMA), either alone (n = 34) or in combination with the coeliac trunk (n = 6), was the predominant target vessel. No patient died within 30 days. Median follow-up was 43 (i.q.r. 25–63) months and the estimated (s.e.) 3-year overall survival rate was 76(7) per cent. Two patients died from distal SMA occlusive disease and intestinal infarction after 6 and 18 months respectively. Previous stroke (P = 0·016), male sex (P = 0·057) and age (P = 0·066) were associated with mid-term mortality on univariable, but not multivariable analysis. Reintervention was needed in 14 patients, achieving a 3-year cumulative rate of freedom from recurrent symptoms of 88(5) per cent.

Conclusion

Endovascular treatment provided high early and mid-term survival rates in this series of patients with CMI, with low complication rates.

Predictors of long-term beneficial effects on blood pressure after percutaneous transluminal renal angioplasty in atherosclerotic renal artery stenosis

AIM

This retrospective study evaluated long-term effects of percutaneous transluminal renal angioplasty (PTRA) in atherosclerotic renal artery stenosis (ARAS), and predictors of benefit on blood pressure (BP).

METHODS

During 1997-2003, 234 patients (age 69+/-11 years, 138 [59%] males) underwent PTRA for ARAS at Malmö Vascular Centre. Cure was defined as diastolic (D)BP<90 mmHg and systolic (S)BP <140 mmHg off antihypertensive medication. Improvement was defined as DBP <90 mmHg and/or SBP <140 mmHg on the same or reduced number of medications, or reduction in DBP of >or=15 mmHg with the same or reduced number of medications. Benefit was defined as cure or improvement.

RESULTS

After PTRA, SBP and DBP decreased (P<0.001), and remained lower (P<0.001) until last follow-up after 4.1+/-3.3 years. Antihypertensive medication decreased (P<0.001), and remained lower at one month (P<0.001), one year (P<0.01), and last follow-up (P<0.05). Renal function was unchanged until last follow-up, when it deteriorated (P<0.001). Patients showing benefit of PTRA on BP at last follow-up (N.=150 [64%]) used more antihypertensive drugs before PTRA (P=0.012), especially angiotensin converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) (P=0.010), and diuretics (P=0.015). In logistic regression, use of ACEi or ARBs failed to reach significancy (P=0.054). Patients dying during follow up (N.=100 [43%]) showed higher age (P<0.0001) and s-creatinine (P<0.0001), lower glomerular filtration rate (P<0.0001), and higher frequency of diabetes mellitus (P<0.005). In logistic regression only age (P=0.009) and diabetes mellitus (P=0.014) predicted mortality.

CONCLUSIONS

We confirmed beneficial effects on BP with PTRA in ARAS. ACEi, ARB and diuretic treatment before PTRA predict favourable long-term BP-response in univariate analysis.

Is there a benefit of frequent CT follow-up after EVAR?

OBJECTIVE

Imaging follow-up (FU) after endovascular aneurysm repair (EVAR) is usually performed by periodic contrast-enhanced computed tomography (CT) scans. This study aims to evaluate the effectiveness of CT-FU after EVAR.

METHODS

In this study, 279 of 304 consecutive patients (261 male, aged 74 years (interquartile range (IQR): 70-79 years) with a median abdominal aortic aneurysm (AAA) diameter of 58 mm (IQR: 53-67 mm)) underwent at least one of the yearly CT scans and plain abdominal films after EVAR. All patients received Zenith stent-grafts for non-ruptured AAAs at a single institution. Patients were considered asymptomatic when a re-intervention was done solely due to an imaging FU finding. The data were prospectively entered in a computer database and retrospectively analysed.

RESULTS

As a follow-up, 1167 CT scans were performed at a median of 54 months (IQR: 34-74 months) after EVAR. Twenty-seven patients exhibited postoperative AAA expansion (a 5-year expansion-free rate of 88+/-2%), and 57 patients underwent 78 postoperative re-interventions with a 5-year secondary success rate of 91+/-2%. Of the 279 patients, 26 (9.3%) undergoing imaging FU benefitted from the yearly CT scans, since they had re-interventions based on asymptomatic imaging findings: AAA diameter expansion with or without endoleaks (n=18), kink in the stent-graft limbs (n=4), endoleak type III due to stent-graft limb separation without simultaneous AAA expansion (n=2), isolated common iliac artery expansion (n=1) and superior mesenteric artery malperfusion due to partial coverage by the stent-graft fabric (n=1).

CONCLUSIONS

Less than 10% of the patients benefit from the yearly CT-FU after EVAR. Only one re-intervention due to partial coverage of a branch by the stent-graft would have been delayed if routine FU had been based on simple diameter measurements and plain abdominal radiograph. This suggests that less-frequent CT is sufficient in the majority of patients, which may simplify the FU protocol, reduce radiation exposure and the total costs of EVAR. Contrast-enhanced CT scans continue, nevertheless, to be critical when re-interventions are planned.

Kissing stents in the aortic bifurcation--a valid reconstruction for aorto-iliac occlusive disease

OBJECTIVE

To evaluate outcome and patency predicting factors of kissingstent treatment for aorto iliac occlusive disease (AIOD).

METHODS

Patients treated with kissingstents for AOID between 1995 and 2004 at a tertiary referral center were identified through local databases. Chart review and preoperative images were used for TASC and Fontaine classification. Follow-up consisted of clinical exams, ABI and/or duplex. Patency rates were estimated by Kaplan-Meier analysis, and Cox multivariate regression was used to determine factors associated with patency.

RESULTS

173 consecutive patients (46% male, mean 64 years) were identified. TASC distribution was: A 15%, B 34%, C 10%, D 41%. Mean follow-up was 36 months (range: 1-144). 30-day mortality was 1% (2 patients), and 1-year survival was 91% (157 patients). 2 patients underwent late, open conversion and 13 patients suffered minor puncture site complications. Primary, assisted primary and secondary patency was: 97%, 99% and 100%, and 83%, 90% and 95% at twelve and 36 months respectively. There was no significant difference in patency between the TASC groups. Patency was significantly worse for patients in Fontaine class III.

CONCLUSIONS

Aortoiliac kissing stents is a valid alternative to open repair for TASC A-D lesions. The procedure has low mortality and morbidity and good patency at 3 years.

What to Do When Evidence is Lacking — Implications on Treatment of Aortic Ulcers, Pseudoaneurysms and Aorto-Enteric Fistulae

Present knowledge on natural history and how to treat penetrating aortic ulcers or different forms of pseudoaneurysms with or without infection is limited as there are only case reports and small series of unusual aortic pathology and its treatment available.

Material:

From our centre we collected 65 patients treated with open (n=15) or endovascular reconstruction (n=50) during a 20-year period in the abdominal aorta. These patients are presented including a review of contemporary treatment.

Results:

Endovascular reconstructions seem to reduce morbidity and mortality compared to otherwise extensive open surgery. Even for patients with infectious etiology (mycotic aneurysms, aorto-enteric fistula) endovascular treatment may be a first-hand option bridging to a more elective open repair. However, a large proportion of patients being unfit for further open surgery were solely treated endovascularly and had no major infectious complications in the follow-up. Registers of cases with unusual aortic pathology, not only of those treated but also of those managed conservatively, are needed to define who to treat and if endovascular or open repair should be recommended.

Conclusion:

Endovascular technique is a promising technique for treatment of aortic pseudoaneurysms of different etiologies. We firmly recommend, despite the lack of evidence, that the work up of patients with penetrating aortic ulcers, mycotic or other types of pseudoanerysms as well as aorto-enteric fistulae should enclose both endovascular and open (or combined) treatment modalities. However, our knowledge of the natural history is limited. Therefore, registers of cases with unusual aortic pathology, not only of those treated but also of those managed conservatively, are needed to define who to treat and if endovascular or open repair should be recommended.

EVAR of aortoiliac aneurysms with branched stent-grafts

INTRODUCTION

Branched iliac stent-grafts (bSG) have recently been developed in order to preserve internal iliac artery (IIA) flow in patients with aneurysmal or short common iliac arteries. The aim of this study is to evaluate a single-center experience with bSG for the IIA.

METHODS

Twenty-two male patients (70 (IQR 65-79) years old) underwent EVAR with 23 bSG (1 bilateral repair) between September 2002 and August 2007. Median AAA diameter was 52 (37-60) mm while common iliac diameter on the side of the bSG was 34 (27-41) mm. Two in-house modified Zenith SG and subsequently 21 commercially available bSG (18 Zenith Iliac Side and 3 Helical Branches) were used. Follow-up (FU) included CT at one month and yearly thereafter. Data was prospectively entered in a database.

RESULTS

Primary technical success was 91% (21 bSG). Median FU duration was 20 (8-31) months. One patient (5 %) died after discharge from acute myocardial infarction on day 13. Another patient died 30 months after EVAR of an unrelated cause. The overall bSG patency was 74% due to 6 branch occlusions (2 intraoperative and 4 late). All patients with patent bSG were asymptomatic. Three occlusions were asymptomatic findings on CT, while the other three developed claudication (two patients with contralateral IIA occlusion and one with simultaneous occlusion of the external iliac). One patient (5%) developed an asymptomatic type III endoleak at 1 month and was successfully treated with a bridging SG. Overall, four patients (18%) required reinterventions (1 bilateral stenting of the external iliac arteries, 1 external and 1 internal SG extensions and 1 femoro-femoral cross-over bypass). Nine out of 16 patients (56%) with CT-FU>/=1 year had shrinking aneurysms. There were no postoperative aneurysm expansions.

CONCLUSIONS

EVAR of aortoiliac aneurysms with IIA bSG is a good alternative to occlusion of the IIA in patients with challenging distal anatomy.

Observations on the Failure of Stent-grafts in the Aortic Arch

INTRODUCTION

The results of endovascular stent-grafts in the abdominal aorta and descending thoracic aorta have been encouraging. Expanding the use of thoracic stent-grafts in to the aortic arch has been associated with increasing numbers of complications. Recently isolated cases of stent-graft collapse have been reported.

METHODS

This was a multi-centre European case series. Data was collected retrospectively on seven patients from five experienced endovascular centres with thoracic stent-graft collapse.

RESULTS

Of the seven patients four were treated for traumatic aortic rupture. Six were male, median age 33 (range 17-54) years. During the ensuing 2 months all patients suffered stent-graft collapse. This was symptomatic in 3 patients and the rest were identified on CT. Endovascular management was possible in 6/7 patients using either a balloon expandable stent (n=6) or further stent-graft (n=1). Two patients had persistent type I endoleak despite treatment. Two of the 7 patients died, both of which presented with symptomatic thoracic stent-graft occlusion. Both deaths were a direct result of stent-graft collapse.

CONCLUSIONS

Thoracic stent-graft collapse may be asymptomatic underscoring the importance of stent-graft surveillance. Endovascular management of collapse is possible in most cases using a large balloon expandable stent. Symptomatic collapse is associated with high morbidity and mortality.

Remodeling of the thoracic aorta after stent grafting of type B dissection: a Swedish multicenter study

AIM

Endovascular repair of complicated type B dissections has evolved as a promising alternative to open repair. Previous studies have indicated that continued false lumen flow is a predictor of continued aortic dilatation and risk of rupture during follow-up. This multicenter study was conducted to analyze the postoperative changes of the false lumen after endografting of complicated type B dissections.

METHODS

All patients treated with endovascular stent grafts for thoracic type B dissections at 5 major Vascular Centers in Sweden were identified through local databases. Review of charts and all available pre- and postoperative CT scans were performed to identify demographics, indications for repair as well as postoperative changes of the aorta and false lumen.

RESULTS

A total of 129 patients treated for type B dissections between 1994 and December 2005 were identified. Median radiological follow-up was 14 months. Fourteen patients died perioperatively leaving 115 patients available for analysis. Seventy-four of these had CT imaging of sufficient quality for morphological analysis. The vast majority of acute patients were treated for rupture or end-organ ischemia whereas most chronic patients were treated for asymptomatic aneurysms. In 80% of patients, the false lumen thrombosed along the stent graft but it remained perfused distal to the stent graft fixation in 50% of patients. Only 5% of patients presented with aortic enlargement of the stent grafted area when adequate proximal sealing was achieved. The distal, uncovered aorta displayed expansion in 16% of patients.

CONCLUSIONS

The stent grafted thoracic aorta after type B dissection appears to be stabilized by covering the primary entry site with a stent graft in the majority of both acute and chronic dissections. The uncovered portion of the aorta distal to the stent graft, however, remains at risk of continuous dilatation. Stent grafting for complicated type B thoracic dissections seems to be a treatment option with reasonable morbidity and mortality even though the incidence of severe complications is still significant.

Complicated Acute Type B Dissections—An 8-years Experience of Endovascular Stent-graft Repair in a Single Centre

OBJECTIVE

To analyze the experience of a single centre using stent-grafts for treatment of complicated acute aortic type B-dissections (EVR-ABD).

DESIGN

Retrospective analysis of prospectively collected data from patients undergoing EVR-ABD between January 1997 and December 2004.

METHODS

EVR-ABD was performed in 31 patients (20 males, median age 74 years (IQR: 64-79)). Indications for treatment were aortic rupture (22 patients), intractable pain and hypertension (six patients), acute bowel ischemia (two patients) and transient paraplegia, lower limb and renal ischemia in one patient. Initially home-made devices (five patients) and subsequently commercially available thoracic stent-grafts were used.

RESULTS

Five patients (16%) died within 30 days of EVR-ABD. Postoperative complications occurred in 15 (48%) patients, including one paraplegia converted to paraparesis after cerebrospinal fluid drainage, five strokes, three lower limb ischemia, three myocardial infarction, two pneumonia and one colitis). Re-interventions were required in nine patients (29%). Six more deaths occurred during a median follow-up of 22 (IQR: 16-34) months, two related to the stent-graft and four due to cardiac disease.

CONCLUSIONS

Stent-graft repair of complicated acute type B dissections seems to provide acceptable results and, therefore, it may be considered a valuable alternative to open surgery.

Endovascular Management of Isolated Infrarenal Aortic Occlusive Disease is Safe and Effective in Selected Patients

OBJECTIVE

To examine the safety and efficacy of endovascular management of isolated infrarenal aortic occlusive disease within our centre.

DESIGN AND METHODS

Retrospective analysis of all patients who underwent endovascular treatment of occlusive disease that is confined to the infrarenal aorta between September 1993 and November 2004.

RESULTS

Primary aortic stenting was carried out in 16 women and five men using self-expanding (12 patients) and balloon expanding stents to treat both occlusions (six) and stenoses (15). Indications included intermittent claudication (13), critical limb ischaemia (six), and distal embolisation (three). Significant postoperative complications within 30 days were noted in three, including one death. Fifteen patients completed 1-year follow-up with primary patency in 14 and secondary patency in the remaining patient. Clinical improvement was documented in all patients.

CONCLUSION

Primary stenting for occlusive disease isolated in the infrarenal aorta is relatively safe in selected patients with encouraging early follow-up results.

Endografting of thoracic aortic aneurysms and dissections

3D imaging and endovascular repair have greatly increased the number of interventions in the thoracic aorta. Excellent early results of endovascular repair compensate unproven long term durability. Challenging anatomy is associated with increased risk for late failure of the stent graft (SG) but the option of open repair usually remains and complications from open surgery are also more frequent in these cases. The indications for endovascular repair of the descending aorta include aneurysms larger than 5-6 cm in diameter, pseudoaneurysms and type B dissection complicated by rupture, aortic dilation or distal hypoperfusion. Traumatic transections and certain types of coarctation are also treated endovascularly. Aortic rupture is associated with a high mortality and treatment is attempted liberally. Logistics remain a limitting factor for urgent stent grafting in many centers. Adequate pre and intraoperative imaging is mandatory for correct SG implantation. The mechanical forces of aortic blood flow jeopardize durable fixation of the device. Extended fixation zones of at least 5 cm, generous overlap between SG components and SG positioning along the outer curvature of the sac improve durability. Primary complications include stroke and paraplegia in about 5% of the cases. Late complications are mainly associated with SG dislodgement and inadequate seal. Surveillance is required. Future development focuses on treatment of leasions in the aortic arch. Debranching of the arch and branched SGs are currently being investigated.

Revascularisation of renal artery stenosis caused by fibromuscular dysplasia: effects on blood pressure during 7-year follow-up are influenced by duration of hypertension and branch artery stenosis

Fibromuscular dysplasia (FMD) mainly affects renal arteries. Percutaneous transluminal renal angioplasty (PTRA) and surgery are effective treatments, but long-time follow-up is lacking. Retrospective follow-up for 7.0+/-4.7 years of 69 consecutive patients (age 44+/-13 years) treated for hypertension due to FMD, 59 patients underwent PTRA and eight patients surgery. In two patients no PTRA was performed. Technical success was achieved in 56 (95%) patients undergoing PTRA and all eight undergoing surgery. After successful PTRA, both systolic and diastolic blood pressures (SBP and DBP) had decreased at discharge (from 174+/-33/100+/-13 to 138+/-19/80+/-15 mmHg; P<0.0001), and remained lower at 1 month, 1 year, and last follow-up after 7.0+/-4.7 years (140+/-25/83+/-12 mmHg; P<0.0001). Serum-creatinine had decreased both at 1 year (from 84+/-28 to 75+/-13 micromol/l; P=0.0030) and last follow-up (75+/-16 micromol/l; P=0.0017). The number of antihypertensive drugs decreased (from 2.3+/-1.2 before PTRA to 1.4+/-1.3 at discharge and at 1 month; P<0.0001, and 1.6+/-1.5 at last follow-up; P=0.0011). SBP decreased more after PTRA among patients with FMD only in the main renal artery than in those with branch artery involvement (43+/-29 vs 20+/-41 mmHg; P=0.0198). Beneficial effects on BP, creatinine and antihypertensive drugs also occurred after surgery. Patients on antihypertensive drugs at last follow-up had longer hypertension duration before PTRA than those without (5.9+/-7.7 vs 1.8+/-4.1 years; P=0.0349). Cure was achieved in 16 (24%), improvement in another 26(39%), and benefit in 42(63%). In conclusion, renal artery FMD, PTRA and surgery have beneficial long-term effects, negatively affected by hypertension duration and branch artery involvement.

Endovascular Recanalisation in Occlusive Mesenteric Ischemia—Feasibility and Early Results

OBJECTIVE

To evaluate a single centre experience of endovascular treatment of mesenteric ischemia caused by vascular occlusion.

DESIGN

Retrospective study.

MATERIAL AND METHODS

Between 1995 and 2002 17 patients (12 females; mean age 61 years) with symptoms of bowel ischemia were treated endovascularly for arterial occlusion. Vessels were evaluated with angiography and pressure gradient measured. A mean gradient of > 20 mmHg or a stenosis of > 50% was considered significant. Patient data were recorded prospectively and follow-up was supplemented with retrospective chart review. Fifteen patients had follow up imaging, median 10 months (3-29 months) postoperatively. Median clinical follow up was 14 months (5-42 months).

RESULTS

Recanalisation was successful in 16 patients (94%). The average number of stents used was 1.6 per patient. For one patient recanalisation failed with subsequent SMA dissection. A celiac artery stenosis was stented but symptoms remained postoperatively. Perioperative mortality was 5.8% (n = 1). 14/17 patients (82%) displayed symptom relief/improvement. Six patients required secondary endovascular intervention; PTA (n = 3); stent/stentgraft (n = 3). Two of these patients required a third procedure. 4/6 patients that underwent secondary intervention were asymptomatic and of recurrent stenosis > 75% and a gradient > 15 mmHg mean pressure gradient on imaging. Two patients were treated because of a combination of angiographic findings and/or significant pressure gradient combined with clinical symptoms.

CONCLUSIONS

Endovascular treatment of mesenteric ischemia due to vessel occlusion is feasible with acceptable short-term results and limited complications. Most patients experience relief/improvement of symptoms. A significant number of patients might need endovascular re-intervention because of restenosis.

Pulsatile Wall Motion (PWM) Measurements after Endovascular Abdominal Aortic Aneurysm Exclusion are not Useful in the Classification of Endoleak

The pulsatile wall motion (PWM) of AAA is reduced after endovascular stent-graft placement. The purpose of this study was to identify whether PWM after endografting was useful in the classification of endoleak.

PATIENTS AND METHODS

162 patients treated with EVAR underwent pre- and post-operative PWM assessment with ultrasonography. Follow-up was 1-9 years. 111 patients had well-excluded aneurysms, three patients had enlarging aneurysms without any recognizable endoleak (endotension), 16 had type I, 31 had type II and 1 had type III endoleak.

RESULTS

The PWM was reduced from about 1mm pre-operatively to 0.24 mm post-operatively in well-excluded aneurysms. PWM remained stable during follow-up. Type I endoleak was associated with moderately reduced PWM (proximal endoleak 0.79 mm and distal 0.32 mm). PWM in patients with type II endoleak was higher (0.32 mm) post-operatively (p=0.002) compared to well-excluded aneurysms.

CONCLUSION

PWM is permanently reduced after endografting. The smallest reduction in PWM was in patients with type II endoleaks. However, the overlap between the groups does not allow reliable identification of patients having endoleak with PWM-measurements.

Sustained beneficial effects on blood pressure during long time retrospective follow-up after endovascular treatment of renal artery occlusion

We retrospectively evaluated short- and long-term effects of percutaneous transluminal renal angioplasty (PTRA) with or without stent placement of renal artery occlusion (RAO) upon blood pressure (BP), serum (s)-creatinine, and the need for antihypertensive treatment in 34 RAO patients who underwent PTRA during 1996-2002. In 24/34 (71%) treatment was considered technically successful, 22/24 (92%) were treated with PTRA + stent, two with only PTRA. Patients were followed for mean 2.6 (range 0-8) years, during which 14/34 (41%) patients died. In all 34 patients, systolic and diastolic BP (SBP and DBP) before treatment were 184 +/- 30/95 +/- 15 mmHg and had decreased at discharge (to 157 +/- 21/80 +/- 10 mmHg; P < 0.001 for both SBP and DBP), and remained lower after 1 year (154 +/- 20/83 +/- 7 mmHg; P < 0.001 for SBP and P < 0.01 for DBP), and at last follow-up (148 +/- 20/80 +/-12 mmHg; P < 0.001 for both SBP and DBP). No changes occurred in s-creatinine or the number of antihypertensive drugs. Similar results were seen in the subgroup of 24/34 (71%) patients in whom treatment was technically successful. Among the 24 patients undergoing technically successful PTRA, absence of nephrosclerosis (P = 0.035) and a shorter duration of hypertension (P = 0.020) predicted favourable clinical outcome. No adverse effects upon s-creatinine or the need for antihypertensive medication were seen in patients in whom treatment was considered a technical failure. Seven of these patients were treated with PTRA of another renal artery than the occluded, or with embolisation. In conclusion, RAO can be treated with endovascular techniques. Technically successful results with decreasing blood pressure levels were obtained in 71% of patients.

Percutaneous Transluminal Renal Angioplasty (PTRA) and Surgical Revascularisation in Renovascular Disease—A Retrospective Comparison of Results, Complications, and Mortality

OBJECTIVE

To evaluate results, complications and mortality following percutaneous transluminal renal angioplasty (PTRA) and open surgical revascularisation for renovascular disease.

METHODS

A retrospective evaluation of 381 renovascular patients (median age 64, range 9-99 years, 152 women) treated at Malmö University Hospital during 1987-1996. Two hundred and sixty-two (69%) of the patients were treated with PTRA, 106 (28%) with open revascularisation.

RESULTS

Thirty-day mortality was 2% in the PTRA group and 9% after open surgery (p<0.001). There were no differences between groups concerning the number of re-do procedures, but first re-do was performed after seven (IQR 3-14) months in the PTRA group, and after 15 (IQR 10-44) months after open revascularisation (p<0.0001). After a median follow-up of 4 months (IQR 0-13) systolic and diastolic blood pressure (BP) had decreased (p<0.0001) in both groups. The number of antihypertensive drugs was reduced (p<0.0001) and S-creatinine levels were unchanged in both groups. Long-time survival assessed with log-rank analysis was better (p<0.01) in the PTRA group. The risk ratio for death with open revascularisation was 1.69 (p<0.01).

CONCLUSIONS

In this retrospective comparison, PTRA was as effective as open revascularisation, with lower complication rate and lower early and long-time mortality, but with shorter time to first re-do.

Does the wide application of endovascular AAA repair affect the results of open surgery?

PURPOSE

to examine the effect of the adoption of endovascular aneurysm repair (EVAR) on the outcome of open repair (OR).

METHODS

between May 1998 and December 2001, EVAR (Zenith) was performed in 117 patients, and OR was performed because of anatomic restrictions in 40 (group A), and because of young age in 11 patients (group B).

RESULTS

EVAR patients had higher ASA classifications (p < 0.0001). EVAR was associated with a 98.3% (115 patients) technical success rate, one conversion to OR and one fatal cardiac arrest. Thirty-day mortality was 2.6% (3 patients) in EVAR, 15% (6 patients) in group A and none in group B. There was no difference in late survival between the three groups. Late reinterventions, mainly endovascular, were more frequent in EVAR. At a median follow-up of 17 months one stent-graft had migrated 5 mm distally and five stents had fractured, but without clinical consequence.

CONCLUSIONS

EVAR provides good results even with inclusion of high-risk patients. The adoption of EVAR may adversely affect the results of OR offered to patients because of anatomic considerations. However, OR continues to be the first option for low-risk young patients.

[Ruptured abdominal aortic aneurysm. Endovascular treatment under local anesthesia]

We report on endovascular repair of a ruptured abdominal aortic aneurysm. A bifurcated stent graft was inserted under local anesthesia. Aortic clamping is rapidly provided by percutaneous placement of an aortic occlusion balloon catheter. Carbon dioxide can usually replace conventional contrast in patients with renal insufficiency. This minimally invasive procedure may reduce perioperative morbidity and mortality in patients with ruptured aortic aneurysms. The advantages and limitations of this novel technique are discussed.

The impact of stent-graft development on outcome of AAA repair--a 7-year experience

OBJECTIVE

to analyse the impact of stent-graft (SG) design and operator skill on the outcome of endovascular AAA repair.

DESIGN

prospective non-randomised open.

MATERIAL

a total of 158 patients (mean age 71) underwent SG repair. Patients were treated with five different types of SG: first (n =58) and second ( n =17) generation Ivancev-Malmö monoiliac SG (IM I and IM II respectively) combined with femoral-femoral crossover, Chuter bifurcated SG (n =15), Vanguard SG ( n =15) and the Zenith SG ( n =53).

METHODS

patients underwent DSA and contrast CT preoperatively and were then followed with CT and digital scans. Recently, one change in AAA diameter and endoleaks (EL) were recorded. Mortality, complications and secondary interventions were recorded and life-table analysis for intervention-free SG survival calculated.

RESULTS

immediate and late conversions as well as 30-day mortality were reduced for 2nd (Zenith and Vanguard) compared to 1st generation SG (IM I, Im II and chuter). SG migrations occurred only with the IM I and Chuter SG. Type I EL were significantly more common in 1st generation SG. First generation SG required significantly more secondary interventions than 2nd SG up to 20 months post-operatively. The number of unplanned intraoperative adjunctive manoeuvres was increased with 2nd SG.

CONCLUSIONS

enhanced SG design has improved the probability of SG success after endovascular AAA repair. Better technical skills may also have contributed to improved results.