Long-Term Results of Endovascular Treatment of Atherosclerotic Stenoses or Occlusions of the Coeliac and Superior Mesenteric Artery in Patients With Mesenteric Ischaemia.

INTRODUCTION: Over the past decade, primary percutaneous mesenteric artery stenting (PMAS) has become an alternative to open revascularisation for treatment of mesenteric ischaemia. Institutes have presented favourable short-term outcomes after PMAS, but there is a lack of data on long-term stent patency. METHODS: One hundred and forty-one patients treated by PMAS for acute and chronic mesenteric ischaemia over an 8 year period were studied. Anatomical success was assessed by duplex ultrasound and/or CT angiography. A stenosis ≥70% was considered to be a failure. RESULTS: Eighty-six coeliac arteries (CA) and 99 superior mesenteric arteries (SMA) were treated with PMAS in 141 patients. Nine CAs (10%) and 30 SMAs (30%) were occluded at the time of treatment. Median follow-up was 32 months (IQR 20-46). The overall primary patency rate at 12 and 60 months was 77.0% and 45.0%. The overall primary assisted patency rate was 90.3% and 69.8%. Overall secondary patency was 98.3% and 93.6%. CONCLUSION: This study shows excellent long-term secondary patencies after PMAS, comparable with published data on long-term patencies after open surgical revascularisation.

The Effect of Unenhanced MRI on the Surgeons' Decision-Making Process in Females with Suspected Appendicitis.

BACKGROUND: This prospective study evaluated the impact of the results of unenhanced magnetic resonance imaging (MRI) on the surgeon's diagnosis of acute appendicitis in potentially fertile females. METHODS: 112 female patients, aged 12-55, with suspected appendicitis underwent MRI of the abdomen. At three defined intervals; admission and clinical re-evaluation before and after revealing the MRI results, the surgeon recorded the attendance of each patient in operative treatment, observation or discharge. Appendicitis was confirmed or declined by pathology or by telephone follow-up in case of non-intervention. FINDINGS: Appendicitis was confirmed in 29 of 112 patients. At admission the surgeon's disposition had a sensitivity of 97 % and specificity of 29 %. After knowing the MRI results, sensitivity was 97 % and specificity 64 %. The sensitivity and specificity of MRI alone were 89 and 100 %, with a negative and positive predictive value of 96 and 100 %, respectively. CONCLUSION: We believe that MRI should perhaps be standard in all female patients during their reproductive years with suspected appendicitis. It avoids an operation in 32 % of cases and allows earlier planning for patients with an equivocal clinical picture. Trial number: OND1292733 (Narcis.nl).

Long Term Results of Kissing Stents in the Aortic Bifurcation.

BACKGROUND: To evaluate the long-term outcome after aortoiliac kissing stent placement and to analyze variables, which potentially influence the outcome of endovascular reconstruction of the aortic bifurcation. METHODS: All patients treated with aortoiliac kissing stents at our institution between April 1995 and August 2011 were retrospectively identified from a prospective single-center database. Data regarding patient characteristics (age, gender, smoking, cardio- and cerebrovascular risk factors, hyperlipidaemia, diabetes mellitus and use of antihypertensive medication), symptoms, pre-interventional examination and imaging, procedural details and follow-up were retrieved. Patency rates were calculated with Kaplan-Meier analysis. Factors affecting the patency were determined with Cox uni- and multivariate analysis. RESULTS: A total of 215 patients (63% men, mean age 61 ±â€ˆ10 years) were included. The median follow-up period was 31 (IQR 47.1) months. Primary, primary assisted, and secondary patency rates were 97%, 97%, and 99%, respectively, at one month; 92%, 95% and 94% at four months; 75%, 86%, and 91% at two years; 70%, 81%, and 91% at 5 years; and 67%, 81%, and 91% at ten years. Younger age and previous aortoiliac treatment were predictors for reduced primary and primary assisted patency. Smoking, previous aortoiliac intervention, TASC C and D lesions were predictors for reduced secondary patency. CONCLUSIONS: Reconstruction of the aortoiliac bifurcation with kissing stents is feasible, safe and effective in all types of lesions with satisfying long term patencies. TASC C and D lesions are associated with a higher occlusion rate. Younger age and previous aortoiliac interventions are predictors for reduced primary and primary assisted patency.

Superior two-year results of externally unsupported polyester compared to supported grafts in above-knee bypass grafting: a multicenter randomised trial.

OBJECTIVES: The aim of this study was to compare externally supported thin wall knitted polyester (P-EXS) and externally unsupported thin wall knitted polyester (P-non-EXS) for above-knee (AK) femoro-popliteal bypass grafting. DESIGN: A prospective multicenter randomised clinical trial. MATERIAL AND METHODS: Between 1999 and 2008, 265 AK femoro-popliteal bypass grafts (6 mm in diameter) were performed, including 136 P-EXS and 129 P-non-EXS. The selection of patients was based on the presence of disabling claudication or critical ischaemia. Follow-up took place at 3, 6, 12, 18, and 24 months and included clinical examination and duplex ultrasonography. The main end points of this study were primary patency rates at one and two years. Secondary end points were mortality, and primary assisted and secondary patency rates. Cumulative patency rates were calculated with life-table analysis and log-rank testing. RESULTS: The 1-year primary, primary assisted and secondary patency rates were 65%, 70% and 84%, respectively, for P-EXS and 76% (p = 0.05), 82% (p = 0.03) and 88% (p = 0.35), respectively, for P-non-EXS. Two-year primary, primary assisted and secondary patency rates were 45%, 57% and 70%, respectively, for P-EXS and 62% (p = 0.003), 75% (p = 0.005) and 84% (p = 0.02), respectively, for P-non-EXS. The overall mortality rate after two years was 11.3%. CONCLUSION: In above-knee femoro-popliteal bypass grafting patency rates of externally supported knitted polyester grafts were inferior to their unsupported counterpart. ISRCTN: At the time this study started this number was not the standard.

Splanchnic artery stenosis and abdominal complaints: clinical history is of limited value in detection of gastrointestinal ischemia.

BACKGROUND: Splanchnic artery stenosis is common and mostly asymptomatic and may lead to gastrointestinal ischemia (chronic splanchnic syndrome, CSS). This study was designed to assess risk factors for CSS in the medical history of patients with splanchnic artery stenosis and whether these risk factors can be used to identify patients with high and low risk of CSS. METHODS: All patients referred for suspected CSS underwent a standardized workup, including a medical history with questionnaire, duplex ultrasound, gastrointestinal tonometry, and angiography. Definitive diagnosis and treatment advice was made in a multidisciplinary team. Patients with confirmed CSS were compared with no-CSS patients. RESULTS: A total of 270 patients (102 M, 168 F; mean age, 53 years) with splanchnic artery stenosis were analyzed, of whom 109 (40%) had CSS and 161 no CSS. CSS-patients more often reported postprandial pain (87% vs. 72%, p = 0.007), weight loss (85% vs. 70%, p = 0.006), adapted eating pattern (90% vs. 79%, p = 0.005) and diarrhea (35% vs. 22%, p = 0.023). If none of these risk factors were present, the probability of CSS was 13%; if all were present, the probability was 60%. Adapted eating pattern (odds ratio (OR) 3.1; 95% confidence interval (CI) 1.08-8.88) and diarrhea (OR 2.6; 95% CI 1.31-5.3) were statistically significant in multivariate analysis. CONCLUSIONS: In patients with splanchnic artery stenosis, the clinical history is of limited value for detection of CSS. A diagnostic test to detect ischemia is indispensable for proper selection of patients with splanchnic artery stenosis who might benefit from treatment.

Dacron or ePTFE for femoro-popliteal above-knee bypass grafting: short- and long-term results of a multicentre randomised trial.

OBJECTIVES: To compare expanded polytetrafluoroethylene (ePTFE) prosthesis and collagen-impregnated knitted polyester (Dacron) for above-knee (AK) femoro-popliteal bypass grafts. DESIGN: A prospective multicentre randomised clinical trial. PATIENTS AND METHODS: Between 1992 and 1996, 228 AK femoro-popliteal bypass grafts were randomly allocated to either an ePTFE (n=114) or a Dacron (n=114) vascular graft (6mm in diameter). Patients were eligible for inclusion if presenting with disabling claudication, rest pain or tissue loss. Follow-up was performed and included clinical examination and duplex ultrasonography at all scheduled intervals. All patients were treated with warfarin. The main end-point of this study was primary patency of the bypass graft at 2, 5 and 10 years after implantation. Secondary end-points were mortality, primary assisted patency and secondary patency. Cumulative patency rates were calculated with life-table analysis and with log-rank test. RESULTS: After 5 years, the primary, primary assisted and secondary patency rates were 36% (confidence interval (CI): 26-46%), 46% (CI: 36-56%) and 51% (CI: 41-61%) for ePTFE and 52% (CI: 42-62%) (p=0.04), 66% (CI: 56-76%) (p=0.01) and 70% (CI: 60-80%) (p=0.01) for Dacron, respectively. After ten years these rates were respectively 28% (CI:18-38%), 31% (CI:19-43%) and 35% (CI: 23-47%) for ePTFE and 28% (CI: 18-38%), 49% (CI: 37-61%) and 49% (CI: 37-61%) for Dacron. CONCLUSION: During prolonged follow-up (10 years), Dacron femoro-popliteal bypass grafts have superior patency compared to those of ePTFE grafts. Dacron is the graft material of choice if the saphenous vein is not available.

The Anaconda AAA stent graft system: 2-year clinical and technical results of a multicentre clinical evaluation.

INTRODUCTION: This study reports the technical and mid-term clinical results of the second-generation Anaconda AAA Stent Graft System endovascular device for treatment of abdominal aortic aneurysm (AAA). The design of the Anaconda AAA Stent Graft System is characterised by a three-piece system consisting of two proximal independent saddle-shaped nitinol self-expandable rings with hooks fixation, zero body support and vacuum-cleaner tube leg design. METHODS: From July 2002 to April 2005, a total of 61 patients with AAA were enrolled in a multicentre, prospective, non-randomised controlled design study. All patients received a second-generation Anaconda AAA Stent Graft System. They entered a standard follow-up protocol at discharge for 3, 6, 12 and 24 months. Follow-up data included survival; rupture-free survival; incidence of aneurysm rupture, death from aneurysm rupture, aneurysm-related death; freedom from aneurysm expansion; freedom from Types I and III endoleaks; endograft patency and technical and clinical success rates. RESULTS: Successful access to the arterial system was achieved in all patients. The primary technical success was 59 out of 61 and the primary assisted technical success was 60 out of 61. All endovascular grafts were patent without significant twists, kinks or obstructions. Migration was not observed in any of the grafts. During the first 30-day period, two serious adverse events (3%), both not related to the procedure, were observed. Nine patients (15%) needed a secondary intervention; two of these interventions were related to stent graft (3%). The mean aneurysm sac diameter decreased significantly from 57 mm pre-operative to 45mm after 24 months, without aneurysm growth. There was one Type I endoleak at initial implantation, which was corrected using a proximal extension cuff. In total, three Type II endoleaks were still present after 24 months without any signs of aneurysm growth. CONCLUSION: The design features of the second-generation Anaconda AAA Stent Graft System are effective in the treatment of AAAs on mid-term evaluation.

The Impact of Revascularisation on Quality of Life in Chronic Mesenteric Ischemia.

Background: Chronic mesenteric ischemia (CMI) is characterized by long-standing abdominal symptoms due to insufficient mesenteric circulation. Data on the effect of revascularisation on quality of life (QoL) for CMI are scarce. This study is the first to evaluate the impact of revascularisation on quality of life. Methods: Seventy-nine patients with CMI or acute-on-chronic mesenteric ischemia (AoCMI) underwent an intervention of one or more mesenteric arteries between January 2010 and July 2012. QoL before and after intervention was measured with the EuroQol-5D. Preintervention questionnaires were of standard care. Postintervention data were obtained by resending a questionnaire to the patients between February and May 2013. To investigate the clinical relevance of our findings, the minimal clinically important difference (MCID) was used. Since there is no established MCID for CMI, we used the literature reference MCID of inflammatory bowel syndrome (IBS) of 0.074. Results: Fifty-five (69.6%) of 79 patients returned their questionnaire and 23 (29.1%) were completely filled out. There was a significant increase of the median EQ-index score from 0.70 to 0.81 (p=0.02) and a significant reduction of symptoms in the domains usual activities (34.4%) and pain/discomfort (32.3%). There was a significant improvement of 17% in overall current health condition (VAS) (p=0.001). The MCID between baseline and postoperative EQ-5D index score was 0.162, indicating a clinically relevant improvement of quality of life after revascularisation. Conclusion: Quality of life of CMI patients is improved after mesenteric artery revascularisation.

[Gastrointestinal ischaemia during physical exertion as a cause of gastrointestinal symptoms]. / Maag-darmischemie tijdens lichamelijke inspanning als oorzaak van gastro-intestinale klachten.

Gastrointestinal (GI) symptoms are reported by up to 70% of endurance athletes. Although exercise leads to decreased gastrointestinal blood flow, GI-ischaemia is rarely reported as a cause. Mucosal ischaemia may result in nausea, abdominal cramps and bloody diarrhoea. After exercise, reperfusion damage and endotoxaemia may cause systemic symptoms as well. In three patients, two women aged 46 and 25 respectively and a man aged 40, with a heterogeneous presentation of exercise induced GI-symptoms, GI-ischaemia was demonstrated using gastric exercise tonometry. Gastric tonometry is mandatory for the diagnosis and follow-up. In the first patient, an isolated celiac artery stenosis was found; after incision of the left crus of the diaphragm, she was asymptomatic and the results of gastric tonometry improved. The other two patients had non-occlusive ischaemia associated with high exercise intensity. Reduction of the exercise intensity resulted in the complaints disappearing.

Acute stress-related gastrointestinal ischemia.

We report a case of acute gastrointestinal ischemia during a very stressful event in whom the diagnosis was made by 24-hour tonometry. This case report unequivocally links a stressful event with increased catecholamine release and subsequent severe symptomatic gastrointestinal ischemia. The role of ischemia as potential pathophysiological mechanism has never been studied in detail. The clinical significance of finding such an association is underscored by this case report, where a vasoactive drug normally used for hypertension treatment resulted in greatly improved abdominal symptoms.

Validation of open-surgery VR trainer.

VREST (Virtual Reality Educational Surgical Tools) is developing a universal and autonomous simulation platform which can be used for training and assessment of medical students and for continuing education of physicians. With the VREST - Virtual Lichtenstein Trainer, simulating the open surgery procedure of the inguinal hernia repair according to Lichtenstein, the validation of the simulator is ongoing. Part of this trajectory is the evaluation of the transfer of training of the virtual incision making. One group of students trained incision making on the VREST platform where the control group did not. In an experiment both groups has to perform several incision tasks on a manikin. The results are not available yet but will be presented at the MMVR14 conference.

Open surgery in VR: inguinal hernia repair according to Lichtenstein.

VREST (Virtual Reality Educational Surgical Tools) is developing a universal and autonomous simulation platform which can be used for training and assessment of medical students and for continuing education of physicians. A workstation consisting of two haptic devices and a 3D vision system is part of the VREST platform. Another part of the platform is a generic software environment in which lessons can be built by the teacher and performed by their students. Using the platform one can see, feel and decide as in reality. With the assessment tool the progress and skills of the students can be supervised. The first lesson build on the VREST platform is an inguinal hernia repair according to Lichtenstein. This is an open surgery procedure. The VREST platform is used prior to the first operating room surgery of the resident. Interactive models and case dependent feedback is used to enlarge the residents' cognition. This should reduce the training time in the operating room.

[Preference for endovascular aortic aneurysm repair: results of RCTs versus nationwide audits]. / Voorkeur voor endovasculair aorta-aneurysmaherstel: Resultaten van RCT's versus landelijke audits.

This short comment puts into perspective the value of randomised controlled clinical trials in comparison with nationwide audits in the field of aortic aneurysm treatment. RCTs represent greater scientific value but nationwide audits represent daily practices and seem to be more appropriate for shared decision-making.

Analysis of the balance between proliferation and apoptosis of cultured vascular smooth muscle cells for tissue-engineering applications.

Tissue homeostasis, the balance between cell proliferation and apoptosis, is an important factor in tissue engineering. We describe a new method to analyze markers of both proliferation and apoptosis in a single assay to monitor growth behavior of cell cultures. Human vascular smooth muscle cells (VSMCs) were cultured either on gelatin-coated tissue culture polystyrene or in three-dimensional porous scaffolds composed of insoluble collagen and elastin. mRNA concentrations of cyclin E, as a marker of proliferation, and of tissue transglutaminase (tTG) as a marker of apoptosis, quantified by a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and normalized to porphobilinogen deaminase mRNA concentrations, were analyzed. tTG mRNA expression levels were increased when apoptosis was induced by tumor necrosis factor-alpha in combination with cycloheximide or by culturing the cells in serum-free culture medium. Cyclin E mRNA expression levels were less altered in these cell cultures. Results were compared with several reference tests to measure apoptosis including DNA fragmentation, annexin V staining, and light microscopy. This RT-PCR method could be used to characterize cell growth behavior of VSMCs in vitro. In addition, it was shown that this test is suitable to measure the balance between proliferation and apoptosis of VSMCs present in tissue-engineered constructs.

The VREST learning environment.

The VREST learning environment is an integrated architecture to improve the education of health care professionals. It is a combination of a learning, content and assessment management system based on virtual reality. The generic architecture is now being build and tested around the Lichtenstein protocol for hernia inguinalis repair.

Chronic splanchnic ischaemia.

Chronic splanchnic ischaemia is a relatively unusual clinical entity consisting of pain and/or weight loss and caused by chronic splanchnic disease (i.e. stenosis and/or occlusion of the coeliac and superior mesenteric artery). The occlusive disease is usually caused by atherosclerosis and is in itself not rare in older individuals. Extensive collateral circulation can develop between the three splanchnic arteries and may compensate for the decreased splanchnic perfusion over time. The pathophysiology of chronic splanchnic ischaemia has still not been completely elucidated.A reliable diagnosis of chronic splanchnic ischaemia, based on a proven causal relationship between the occlusive disease and the symptoms, can be very difficult. Traditionally, tests for evaluating the haemodynamic consequences of the vascular stenoses were not available. Important improvements in establishing a more reliable diagnosis have been achieved with duplex ultrasound and magnetic resonance evaluation of the splanchnic circulation. Tonometry is another promising functional test that may prove useful not only for gaining greater insight into the pathophysiology of chronic splanchnic ischaemia but also for the clinical evaluation of this syndrome. The natural history of chronic splanchnic disease suggests that progressive disease may result in acute mesenteric ischaemia. Surgical reconstruction of the coeliac and/or the superior mesenteric artery is the therapeutic standard with excellent short and long-term results. Satisfactory early results using angioplasty with or without stent suggest that this type of intervention may relieve symptoms in selected patients with a higher surgical risk.

Exercise induces gastric ischemia in healthy volunteers: a tonometry study.

Heavy physical exercise may cause gastrointestinal signs and symptoms, and, although splanchnic blood flow may decrease through redistribution by more than 50%, it is unclear whether these signs and symptoms relate to gastrointestinal ischemia. In 10 healthy volunteers, we studied the effect of exercise on gastric mucosal perfusion adequacy using air tonometry. Two relatively short (10 min) exercise stages were conducted on a cycle ergometer, aiming for 80 and 100% of maximum heart rate, respectively. The intragastric-arterial PCO(2) gradient (Delta PCO(2)) was elevated by 1.1 +/- 1.0 kPa over baseline values (-0.1 +/- 0.3 kPa) only after maximal exercise (P < 0.001). Delta PCO(2) positively correlated with the arterial lactate level taken as an index of exercise intensity (Spearman's rank test: r = 0.76, P < 0.0001). By bilinear regression analysis, a lactate level of 12 mmol/l, above which a sharp rise in the Delta PCO(2) occurred, was calculated. We conclude that, in healthy volunteers with normal splanchnic vasculature, gastric ischemia may develop during maximal exercise as judged from intragastric PCO(2) tonometry.

Chronic mesenteric vascular syndrome. Results of reconstructive surgery.

Since 1961, 14 patients at the University Hospital of Leiden, the Netherlands, have undergone reconstructive surgery for treatment of chronic mesenteric vascular syndrome. Of the 42 mesenteric arteries, 31 were severely obstructed (mean, 2.2 stenotic arteries per patient). A total of 23 mesenteric arteries were repaired. Long-term follow-up data were available for all 13 surviving patients (mean follow-up, 11.8 years). Symptoms were relieved immediately after surgery, and relief was maintained during follow-up. Digital subtraction angiography at long-term follow-up evaluation was performed in eight patients (13 reconstructions) with these results: 11 (85%) of the 13 reconstructions were patent and severe stenoses were found in eight (33%) of the 24 mesenteric arteries (mean, 1.0 stenotic artery per patient). We conclude that reconstructive surgery for patients with chronic mesenteric vascular syndrome promptly relieves symptoms, provides excellent patency, and has long-lasting beneficial results.

Pitfalls in the diagnosis of origin stenosis of the coeliac and superior mesenteric arteries with transabdominal color duplex examination.

The purpose of this study is to evaluate the effects of respiration, localization of the Doppler sample, and the presence of origin stenosis on the Doppler parameters of coeliac and superior mesenteric arteries in 22 patients undergoing elective abdominal vascular reconstructive surgery under standardized stable anesthesia. Deep inspiration decreased peak systolic and end diastolic velocities of the coeliac artery origin. Proximal to distal Doppler velocities of normal coeliac and superior mesenteric artery origins were comparable. However, in the presence of an origin stenosis, the increase of Doppler velocities at the origin of the coeliac and superior mesenteric arteries is likely to be missed by transabdominal scanning.

Duodenal meal stimulation leads to coeliac artery vasoconstriction and superior mesenteric artery vasodilatation: an intra-abdominal ultrasound study.

To evaluate the influence of duodenal feeding on splanchnic blood flow, 14 patients with normal coeliac and superior mesenteric arteries underwent intra-abdominal duplex scanning of the systemic and splanchnic circulation under standardised basal and meal-stimulated conditions. Doppler samples and diameter measurements were taken of the aorta, coeliac artery, common hepatic artery, splenic artery, superior mesenteric artery, and inferior mesenteric artery. Duodenal meal stimulation has no systemic effects (p > 0.4). However, duodenal meal stimulation results in coeliac artery vasoconstriction (p < 0.06) and superior mesenteric artery vasodilatation (p < 0.05). This study supports other reported results that gastrointestinal blood flow is dependent on the site of food stimulation.