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J H van Bockel

Publications and source records attributed to J H van Bockel.

At least 19 recordsLinked to original sources
PubMed2001

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.

Angiography↗
PubMed2000

Accelerated atherosclerosis by placement of a perivascular cuff and a cholesterol-rich diet in ApoE*3Leiden transgenic mice.

Intimal hyperplasia after vascular injury is usually studied in animal models with healthy, normocholesterolemic animals. Here, we assess the effect of diet-induced hypercholesterolemia on the induction of intimal hyperplasia in ApoE*3Leiden mice. A nonconstrictive polyethylene cuff was placed around the femoral artery of ApoE3*Leiden mice fed a highly cholesterol-rich diet, a mildly cholesterol-rich diet, or a chow diet for 4 weeks. Diets were continued after cuff placement until euthanization. At several time points (1 to 14 days), mice were euthanized and the intimal hyperplasia in the cuffed arteries was analyzed. In mice fed a chow diet, a 2- to 4-cell-layer-thick intima, predominantly consisting of alpha smooth muscle cell actin-positive cells, was observed after 14 days. A mildly cholesterol-rich diet (mean plasma-cholesterol level, 10.5 mmol/L) resulted in a 2.7-fold increase of total intimal area, and a highly cholesterol-rich diet (mean plasma cholesterol level 28. 6 mmol/L), in a 7.8-fold increase. In the high-cholesterol group, the intima consisted predominantly of lipid-loaded foam cells and alpha smooth muscle cell actin-positive cells. Foam cell accumulation could be observed by as early as 3 days, resulting in a near-total occlusion of the lumen after 14 days. Hypercholesterolemia resulted in a rapid, cholesterol-dependent induction of foam cell-rich intimal hyperplasia in cuffed femoral arteries of ApoE*3Leiden mice. In conclusion, the present data show that the combination of a local (cuff placement) and a systemic (hypercholesterolemic) risk factor of atherosclerosis results in a rapid induction (within 14 days) of atherosclerotic-like lesions in ApoE*3Leiden mice.

Animals↗
PubMed2000

Intraoperative renal duplex sonography: a valuable method for evaluating renal artery reconstructions.

OBJECTIVES: to determine the ability of duplex sonography to intraoperatively detect technical problems with renal artery reconstructions. DESIGN: retrospective evaluation of a standard protocol. PATIENTS AND METHODS: the outcome of intraoperative duplex was compared with postoperative angiography, surface duplex, MRA, echo or direct inspection in case of re-exploration in 77 renal artery reconstructions in 62 patients. These included six extracorporeal reconstructions, eight and 17 reconstructions with an artery and autogenous vein respectively, 10 renal artery re-implantations in the aorta (prosthesis), 32 endarterectomies and four reconstructions of kidney transplant vessels. RESULTS: intraoperative duplex was normal in 67/73 reconstructions with sufficient data. In six cases technical problems were revealed by intraoperative duplex and the reconstruction was re-explored. After re-exploration intraoperative duplex was normal in all cases. Confirmatory studies demonstrated normal results in 61/64 reconstructions with normal intraoperative duplex and abnormal results in 6/6 reconstructions with technical problems revealed by intraoperative duplex. Three reconstructions with normal intraoperative duplex occluded as demonstrated by angiography less than 2 weeks after surgery. CONCLUSIONS: renal duplex sonography is a valuable method available for intraoperative detection of technical problems. Haemodynamic duplex data were less important than B-mode imaging in discriminating between normal and abnormal reconstruction.

Adolescent↗
PubMed2000

Increased local cytostatic drug exposure by isolated hepatic perfusion: a phase I clinical and pharmacologic evaluation of treatment with high dose melphalan in patients with colorectal cancer confined to the liver.

A phase I dose-escalation study was performed to determine whether isolated hepatic perfusion (IHP) with melphalan (L-PAM) allows exposure of the liver to much higher drug concentrations than clinically achievable after systemic administration and leads to higher tumour concentrations of L-PAM. Twenty-four patients with colorectal cancer confined to the liver were treated with L-PAM dosages escalating from 0.5 to 4.0 mg kg(-1). During all IHP procedures, leakage of perfusate was monitored. Duration of IHP was aimed at 60 min, but was shortened in eight cases as a result of leakage from the isolated circuit. From these, three patients developed WHO grade 3-4 leukopenia and two patients died due to sepsis. A reversible elevation of liver enzymes and bilirubin was seen in the majority of patients. Only one patient was treated with 4.0 mg kg(-1) L-PAM, who died 8 days after IHP as a result of multiple-organ failure. A statistically significant correlation was found between the dose of L-PAM, peak L-PAM concentrations in perfusate (R = 0.86, P< or =0.001), perfusate area under the concentration-time curve (AUC; R = 0.82, P<0.001), tumour tissue concentrations of L-PAM (R = 0.83, P = 0.011) and patient survival (R = 0.52, P = 0.02). The peak L-PAM concentration and AUC of L-PAM in perfusate at dose level 3.0 mg kg(-1) (n = 5) were respectively 35- and 13-fold higher than in the systemic circulation, and respectively 30- and 5-fold higher than reported for high dose oral L-PAM (80-157 mg m(-2)) and autologous bone marrow transplantation. Median survival after IHP (n = 21) was 19 months and the overall response rate was 29% (17 assessable patients; one complete and four partial remissions). Thus, the maximally tolerated dose of L-PAM delivered via IHP is approximately 3.0 mg kg(-1), leading to high L-PAM concentrations at the target side. Because of the complexity of this treatment modality, IHP has at present no place in routine clinical practice.

Antineoplastic Agents, Alkylating↗
PubMed2000

Pulsatile wall motion and blood pressure in aneurysms with open and thrombosed endoleaks--comparison of a wall track system and M-mode ultrasound scanning: an in vitro and animal study.

OBJECTIVE: Pulsatile wall motion has been suggested as a means by which to evaluate abdominal aortic aneurysms after exclusion from the circulation to determine whether the treatment has been effective. The objective of this study was to investigate the relations between pulsatile wall motion and both the mean and pulse pressures within the aneurysmal sac for both patent and thrombosed endoleaks. Furthermore, we compared the measurements of pulsatile wall motion by means of M-mode ultrasound scanning and a wall track system to determine the most reliable technique. METHODS: First, interobserver and intraobserver variability of M-mode ultrasound scan measurements was determined at different pressure levels in a cow iliac artery placed in an in vitro circulation. M-mode ultrasound scanning and a wall track system were compared in the same model. Second, in an animal experiment, an aneurysm and endoleak model with both patent and thrombosed endoleaks was created. Systemic and aneurysmal mean and pulse pressures were recorded synchronically with pulsatile wall motion by means of M-mode ultrasound scanning and a wall track system. RESULTS: The intraobserver and interobserver variability values for M-mode ultrasound scan measurement in vitro were 0.11 mm (SD = 0.10 mm) and 0.15 mm (SD = 0.13 mm), respectively. In the animal study, a significant difference existed with respect to the level of pulse pressure within the aneurysmal sac between the group with pulsatile wall motion and the group without such motion (P <.0001). The presence of pulsatile wall motion was not correlated with the level of aneurysmal mean pressure. The level of pulsatile wall motion determined by means of M-mode ultrasound scanning correlated well with the level determined by means of the wall track system (r = 0. 74; P =.01). For the level of pulsatile wall motion determined by means of M-mode ultrasound scanning, a significant difference between patent and thrombosed endoleaks existed (P =.04). For detecting endoleaks, the sensitivity and specificity of pulsatile wall motion as determined by means of the wall track system were 52% and 100%, respectively, and the sensitivity and specificity of pulsatile wall motion as determined by means of M-mode ultrasound scanning were 64% and 67%, respectively. For the detection of pulse pressure in the aneurysmal sac, the sensitivity and specificity of pulsatile wall motion as determined by means of the wall track system were 76% and 100%, respectively, and the sensitivity and specificity of pulsatile wall motion as determined by means of M-mode ultrasound scanning were 90% and 71%, respectively. CONCLUSIONS: We found that pulsatile wall motion is correlated with aneurysmal pulse pressure but not with the mean level of pressure inside the aneurysm. Although measurements of pulsatile wall motion are of great theoretic value when groups of patients who have undergone endovascular aneurysm repair are being compared, this method appears to be unreliable in a clinical setting with respect to determining whether the aneurysmal sac is still pressurized in individual patients.

Animals↗
PubMed2000

Thrombus within an aortic aneurysm does not reduce pressure on the aneurysmal wall.

PURPOSE: The role of thrombus within an aneurysm in relation to the risk of rupture is controversial. In literature, reports describing reduction and increase of rupture risk can be found. In the era of endovascular treatment of abdominal aortic aneurysms, a possible reduction of risk of rupture by the presence of thrombus within the aneurysmal sac can be important in relation to the location of an endoleak to the aneurysmal wall and in relation to the effect of the thrombosis of the endoleak, either spontaneously or by intervention. METHODS: In nine patients who underwent operation for an infrarenal aortic aneurysm by open procedure at the level of the thickest thrombus lining, the pressure within the aneurysmal thrombus (just inside the aneurysmal wall) was measured and compared with the systemic pressure. RESULTS: Pressure within systemic circulation and aneurysmal thrombus correlated well for the mean pressure (r = 0.90; P <.001) and for pulse pressure (r = 0.74; P <.01) Also, there was agreement between the levels of the mean pressure. Conduction of mean and pulse pressure to the aneurysmal wall was not related to the thickness of the thrombus at the level of the pressure measurement (r = 0.18 and r = 0.08, respectively). CONCLUSION: We conclude that thrombus within the aneurysm does not reduce both the mean and the pulse pressure near the aneurysmal wall and thus will not reduce the risk of rupture of the aneurysm.

Aged↗
PubMed1999

Stent attachment site-related endoleakage after stent graft treatment: An in vitro study of the effects of graft size, stent type, and atherosclerotic wall changes.

OBJECTIVE: Perigraft endoleakage is a major complication of the endovascular treatment of abdominal aortic aneurysms. The factors that cause this form of endoleakage are not completely identified. The effect of sizing of the prosthesis in combination with either self-expandable or balloon-expandable stents is evaluated in this study. Further, the influence of atherosclerotic changes on endoleakage is evaluated. METHODS: Eight human abdominal aortas were assessed macroscopically at 11 sites for the presence of atherosclerotic changes with intravascular ultrasound scanning (IVUS) and with computed tomography (CT). Five aortas were placed in in vitro circulation with physiologic parameters. After the determination of the proximal and distal landing site of the stent graft, the diameter and surface measurements of the cross sections were taken. The stent graft diameters were chosen from 4-mm undersizing to 6-mm oversizing, both for Gianturco stent grafts (William Cook Europe A/S, Bjaeverskov, Denmark) and for Palmaz stent grafts (Cordis/Johnson & Johnston Co, Warren, NJ). After placement of the stent graft, the diameter and surface measurements of the aortic cross section were determined at the proximal and distal stent attachment sites. The presence and size of the folds at the stent attachment site and the interface with the aortic wall were determined with IVUS and angioscopy. Endoleakage was evaluated with angiography. After angioplasty of the stent attachment site, IVUS, angioscopy, and angiography were repeated. RESULTS: Regarding atherosclerotic changes of the aortic wall, the correlations between clinical impression and CT, clinical impression and IVUS, and CT and IVUS were high (r = 0.77, r = 0.79 and r = 0.79, respectively). For the Gianturco stent grafts, no significant relationship existed between the diameters measured before and after stent graft placement, leading to great differences in intended and achieved oversizing. The achieved oversizing was less in the case of minimal atherosclerotic changes of the aortic wall. The Gianturco stent graft followed the aortic wall closely during the heart cycle. The sizes of the folds of the fabric were clearly correlated with the achieved oversizing (r = 0.83; P =.04) and the grade of endoleakage (r = 0.88; P =.022). Angioplasty after stent graft placement had no effect on the diameter and the grade of endoleakage. Palmaz stent grafts did not follow the aortic wall during the heart cycle. A significant correlation existed between oversizing and both space between aortic wall and stent graft (r = -0.88; P =.02) and grade of endoleakage (r = 0.84; P =.036). Grade of endoleakage in the Palmaz stent graft group was less than in the Gianturco stent graft group. CONCLUSION: With the use of Gianturco stents, a great difference between intended and achieved oversizing is accomplished. The atherosclerotic changes of the aortic wall possibly affect this finding. The configuration of the Gianturco stent results in the formation of fold in the case of oversizing, which is associated with endoleakage. However, the self-expandable character of the stent leads to a close relation to the aortic wall during the heart cycle, and this may possibly accommodate future aortic neck dilation. The Palmaz stent grafts do not follow the aortic wall during the heart cycle, but they do lead to better interface between the graft and the aortic wall, which results in less endoleakage.

Angioscopy↗
PubMed1999

Long-term outcome of surgical revascularization in ischemic nephropathy: normalization of average decline in renal function.

OBJECTIVE: Renovascular disease may lead to ischemia of the nephrons and to fibrosis, which is generally considered to be irreversible and progressive. We investigated the potential of revascularization to recover and stabilize renal function in patients with ischemic nephropathy. METHODS: In a retrospective analysis of all our 61 patients with ischemic nephropathy who underwent treatment with surgical revascularization, we determined the long-term course of renal function decline with an estimated glomerular filtration rate (EGFR; Cockcroft and Gault formula). With the assumption of normal renal function at age 25 years, the preoperative slope of EGFR and the postoperative slope of EGFR were determined from the EGFR before surgery, at the short-term follow-up examination (on average, 8 months after surgery), and at the long-term follow-up examination (on average, at 47 months after surgery). These declines in renal function were compared with EGFR values in age-matched and sex-matched samples from a large cross-sectional population study. RESULTS: The overall surgical mortality rate amounted to 13.1%. Five patients became dialysis dependent-two with preexisting end-stage renal disease and three at later follow-up examination-and two patients, who before surgery were dialysis dependent, could be withdrawn from dialysis treatment. Shortly after the operation, the mean EGFR level had increased from 28.3 to 43.1 mL/min/1.73 m2 ( P <. 01). The rate of decline in renal function had decreased from an estimated -2.57 mL/min/1.73 m2/year before surgery (weighted mean: interquartile range, -2.71 to -1.98) to -0.66 mL/min/1.73 m2/year (weighted mean: interquartile range, -2.00 to -0.18) in the short-term interval to the long-term interval, which was even slightly better than the slope of -0.84 mL/min/1.73 m 2/year in the age-matched and sex-matched control population. CONCLUSION: Surgical revascularization in selected patients with renovascular disease and ischemic nephropathy restores renal function and makes the average long-term rate of decline in renal function equal to that of the general population. This indicates that in most patients a "point-of-no-return" has not yet been passed even though their renal function is already markedly impaired before surgery. Therefore, in well-selected patients with ischemic nephropathy, considerable improvement of renal function can be realized.

Adult↗
PubMed1999

Reintervention and mortality after infrainguinal reconstructive surgery for leg ischaemia.

BACKGROUND: Progression of atherosclerosis and graft-related complications are common indications for late vascular intervention. The aim of this study was to determine the cumulative risk of late reintervention or death after infrainguinal bypass grafting. METHODS: Some 205 consecutive patients with limb-threatening ischaemia were included. All data were recorded prospectively. The principal endpoint was reintervention for a graft-related complication or recurrent leg ischaemia. Mean follow-up was 3.3 years. Life-table and multivariate analyses were employed to estimate the cumulative risk of reintervention or death during follow-up and to assess factors influencing this risk. RESULTS: Beyond 30 days after insertion of the infrainguinal bypass, 67 patients (33 per cent) had 112 subsequent vascular interventions in the ipsilateral extremity. The cumulative reintervention rate was 25 per cent at 1 year and 40 per cent at 5 years. Poor run-off (P < 0.005) and prosthetic grafts (P < 0.001) were significant and independent risk factors. Long-term survival was poor and affected by the presence of diabetes (P < 0.01) and renal insufficiency (P < 0.01). CONCLUSION: Late reinterventions are common after infrainguinal bypass for limb-threatening ischaemia, and contribute to morbidity and discomfort. Such information is of particular relevance to patients in high-risk groups and should be explained as an integral part of informed consent.

Adult↗
PubMed1999

Endoleak after stent-graft treatment of abdominal aortic aneurysm: a meta-analysis of clinical studies.

BACKGROUND: Endoleak is the major complication after endovascular treatment of abdominal aortic aneurysm (AAA) and its incidence seems to remain significant. Little is known about the association of device type and configuration with respect to the incidence, location, time of onset and fate of endoleakage. METHODS: A meta-analysis was performed via a Medline search of clinical studies after 1995 dealing with the endovascular treatment of AAA. Details of number of patients treated, configuration and type of endovascular device were collected. Data concerning site of origin, time of occurrence and fate of the endoleak were retrieved, along with information on change in diameter of the aneurysm with time. RESULTS: The 23 publications included reported on 1189 patients. The 1118 patients with successfully inserted transfemoral endovascular grafts experienced 270 endoleaks (24 per cent). The majority arose from the distal stent attachment site (36 per cent), were present immediately after stent-graft placement (66 per cent) and were persistent in time (37 per cent). Tube grafts were more frequently affected by endoleakage (35 per cent; P < 0.0001), especially at the distal stent attachment site (51 per cent), than bifurcated grafts (18 per cent; P = 0.004) and aortounilateral devices (20 per cent; P = 0.70). Self- expandable stent-grafts were more frequently associated with endoleaks (25 per cent) than balloon-expandable stent-grafts (17 per cent) (P = 0.037). CONCLUSION: Endovascular treatment of AAA is an evolving field. Even after the initial learning curve and attention to device-related problems, it is still accompanied by a significant number of endoleaks. Uniform presentation of results of treatment is necessary for analysing the effect of differences between patients, aneurysm morphology and device type.

Aortic Aneurysm, Abdominal↗
PubMed1999

Abdominal aortic aneurysm measurements for endovascular repair: intra- and interobserver variability of CT measurements.

OBJECTIVES: to evaluate the intra- and interobserver variability in measurements of the aorta and iliac arteries in patients with abdominal aortic aneurysms (AAAs) considered for endovascular repair using computed tomography angiography (CTA). METHODS: the diameter of the neck, aneurysm, right and left iliac artery were measured by 5 observers in 10 consecutive patients. Measurements were performed on hard copy using a ruler and on a workstation using an electronic caliper. RESULTS: the intraobserver variability showed a decrease going from hard copy to workstation in the standard deviation of the differences of the paired observations for the neck from 3.54 mm to 1.18 mm; for the aorta from 4.16 to 1.72 mm; for the right iliac from 1.87 to 1.01 mm; for the left iliac from 2.07 to 0.87 mm. The interobserver variability showed a similar decrease for the neck in all ten pairs of observers; for the aorta in two, for the right iliac and left iliac in five. However, the difference between observers regularly exceeded 2 mm. CONCLUSION: the use of a workstation and electronic calipers results in lower intra- and interobserver variability. However, the results still show a clinically relevant difference between the observers. Therefore, it is necessary to develop an automatic observer-independent measurement technique.

Angiography↗
PubMed1999

Operations that require supracoeliac aortic cross-clamping: perioperative monitoring with gastric tonometry.

OBJECTIVE: To assess the predictive value of a gastric intramucosal pH of less than 7.35 for mortality in surgical patients after supracoeliac aortic cross-clamping. DESIGN: Open prospective clinical study. SETTING: University hospital, The Netherlands. SUBJECTS: Six patients who required temporary supracoeliac, and four patients who required temporary infrarenal, cross-clamping of the aorta. MAIN OUTCOME MEASURES: Mortality and conventional measures of organ dysfunction correlated with gastric tonometry. RESULTS: All 6 patients who required supracoeliac cross-clamping underwent a steep, and 5 patients a prolonged, decrease in the gastric intramucosal pH. The mean lowest gastric intramucosal pH in the supracoeliac group was 7.05 and in the infrarenal group 7.28. All patients recovered completely. CONCLUSION: A pHig value below 7.35 does not seem to be a marker of mortality in patients who have undergone supracoeliac cross-clamping of the aorta.

APACHE↗
PubMed1998

Morbidity and mortality of reconstructive surgery of noninfected false aneurysms detected long after aortic prosthetic reconstruction.

OBJECTIVE: To determine the morbidity and mortality of surgical treatment of false (anastomotic) aneurysms, we analyzed the results of 158 consecutive surgical procedures for repair of false aneurysms that were detected as a result of a surveillance program after aortic reconstruction with a prosthesis. DESIGN: Retrospective analysis of patient data from a vascular registry that included information on the long-term follow-up of our patients. SETTING: A university hospital (tertiary referral center) in the Netherlands that has been performing vascular reconstructive surgery since 1958. PATIENTS: We performed 158 surgical procedures on 135 patients with 220 noninfected false aneurysms. Using a yearly surveillance program, the false aneurysms were detected at a mean interval of 8 years after the initial reconstruction. Most patients (60%) were asymptomatic. The operation was performed as an emergency in 25 instances (16%). RESULTS: The mortality rate of patients receiving nonsurgical treatment was very high (61%) owing to documented rupture (11 of 18 patients). The intraoperative death rate was 7.6% per procedure. This was higher for emergency (24%) than for elective procedures (4.5%). CONCLUSIONS: Conservative follow-up carries a very high mortality rate, as does emergency surgery for a false aneurysm. However, the intraoperative mortality rate of elective reconstruction of a false aneurysm can be in the same range as that of elective primary aortic reconstruction. Therefore, we advocate a surveillance program, including yearly ultrasound studies, after prosthetic aortic reconstruction for the timely detection and elective repair of all false aneurysms.

Adult↗
PubMed1998

Long-term graft survival after liver transplantation in the UW era: late effects of cold ischemia and primary dysfunction. European Multicentre Study Group.

The use of University of Wisconsin (UW) solution in liver transplantation (LTX) has significantly prolonged preservation times and facilitated semielective transplant procedures. Despite this advantage potential risk factors related to the donor, recipient, or cold storage method will persist in the UW era and detrimental effects will be reflected by primary dysfunction (PDF) after LTX. Concern has been voiced about the maximum period of UW preservation in LTX and various cold ischemia times (CIT) are mentioned. To evaluate the effect of UW solution in LTX, a prospective European multicenter study was initiated in 1988 and short-term results have been reported previously. This report focuses on the long-term effects and survival of prolonged preservation with UW solution and primary function after LTX. Three hundred and fifteen LTXs were performed in 288 patients in participating European centers. Complete follow up of at least 6 years was available for 296 grafts in 277 patients. Effects of donor, preservation, and recipient risk factors on PDF including primary non-function (PNF) and initial poor function (IPF) were evaluated. Next, the effect of risk factors on graft survival (GS) was analyzed including the long-term impact of PNF and IPF using multivariate analyses and the Kaplan-Meyer method. PDF occurred in 15.2% (45/296) with PNF in 7.8% and IPF in 7.4%. Patients with IPF had a 34% lower GS at 3 months those with immediate function (IF; 58% vs 91%; P < 0.001). This difference persisted up to 6 years for patients with IPF with a 39% GS vs 72% after IF (P < 0.001). Median CIT was significantly longer in grafts with PNF compared to IPF or IF (P = 0.03). Long-term GS, however, was significantly influenced at a lower CIT threshold with a 6-year GS for CIT < or = 16 h of 67%, compared to a CIT > 16 h of 51% (P = 0.02). Other independent risk factors for the 6-year survival rate were re-LTX, ABO incompatibility, and recipient diagnosis of acute hepatic failure. In conclusion, liver patients with PNF, but not with IPF, have a significantly lower CIT. IPF is associated with a significantly lower 3 month GS compared to IF, but this difference of 34% does not further increase during a 6-year follow up. Although a short term follow up (3 months) shows that with UW solution CIT up to 18 h has no adverse effect on GS, the 6-year data clearyl suggest that CIT should be kept to less than < 16 h to avoid tetrimental effects on lang-term GS after LTX.

Adenosine↗
PubMed1998

Streptococcus pneumoniae, an emerging pathogen in mycotic aneurysms?

Two patients are described with a mycotic aneurysm caused by streptococcus pneumoniae infection. The patients presented with back pain and fever, and had an antecedent history of lower respiratory tract infection; neither of them were suffering from endocarditis. Mycotic aneurysms are a rare disorder with, over the years, a changing spectrum of presentation, localisation and bacterial aetiology. S. pneumoniae infection has only very rarely been reported as a cause of mycotic aneurysms. Since 1986, 14 patients with a mycotic aneurysm were treated at the Leiden University Hospital. Of these patients, 5 had mycotic aneurysms caused by S. pneumoniae infection. The mortality in these patients was high. In this communication, we would like to draw attention to S. pneumoniae infections as an emerging cause of mycotic aneurysms.

Aged↗
PubMed1998

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.

Aged↗
PubMed1998

Endoleakage after stent-graft treatment of abdominal aneurysm: implications on pressure and imaging--an in vitro study.

BACKGROUND: Endoleakage is a fairly common problem after endovascular repair of abdominal aortic aneurysm and may prevent successful exclusion of the aneurysm. The consequences of endoleakage in terms of pressure in the aneurysmal sac are not exactly known. Moreover, the diagnosis of endoleakage is a problem because visualization of endoleaks can be difficult. METHOD: With an ex vivo model of circulation with an artificial aneurysm managed by means of a tube graft, studies were performed to evaluate precisely known diameters of endoleaks with both imaging techniques (computed tomography and digital subtraction angiography) and pressure measurements of the aneurysmal sac. The experiments were performed without endoleak (controls) and with 1.231-French (0.410 mm), 3-French (1 mm), and 7-French (2.33 mm) endoleaks. Pressure and imaging were evaluated in the absence and presence of a simulated open lumbar artery. The pressure in the prosthesis and in the aneurysmal sac were recorded simultaneously. Digital subtraction angiography with and without a Lucite acrylic plate, computed tomographic angiography, and delayed computed tomographic angiography were performed. For the first experiments, the aneurysmal sac was filled with starch solution. All tests were repeated with fresh thrombus in the aneurysmal sac. RESULTS: Each endoleak was associated with a diastolic pressure in the aneurysmal sac that was identical to diastolic systemic pressure, although the pressure curve was damped. At digital subtraction angiography without a Lucite acrylic plate, the 1.231-French (0.410 mm) endoleak was visualized without an open lumbar artery. When a Lucite acrylic plate was added, the endoleak was not visible until a lumbar artery was opened. In the presence of thrombus within the aneurysmal sac, all endoleaks were not visualized at digital subtraction angiography. At computed tomographic angiography, all endoleaks were not visualized in the absence of a thrombus mass in the aneurysmal sac. In the presence of thrombus within the aneurysmal sac, the 1.231-French (0.410 mm) endoleak became visible after opening of a simulated lumbar artery. At delayed computed tomographic angiography, all endoleaks were visualized without and with thrombus. CONCLUSION: Every endoleak, even a very small one, caused pressure greater than systemic diastolic pressure within the aneurysmal sac. However, small endoleaks were not visualized with digital subtraction angiography and computed tomographic angiography, whereas all endoleaks were visualized with a delayed computed tomographic angiography protocol. We believe that follow-up examinations after stent graft placement for aortic aneurysms should focus on pressure measurements, but until this is clinically feasible, delayed computed tomographic angiography should be performed.

Angiography, Digital Subtraction↗