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H van Urk

Publications and source records attributed to H van Urk.

At least 37 records · Page 2Linked to original sources

Harmonization of vascular surgical training in Europe. A task for the European Board of Vascular Surgery (EBVS).

The competence of vascular surgeons defined as the level of skill, knowledge and experience necessary to safely perform vascular surgical procedures is determined to a high degree by the quality of the preceding training. In Europe, quality assurance of vascular surgical training, unlike in the USA, is not uniform and is not the responsibility of a centralized European authority, but is a matter in which the different countries have autonomous regulations. Consequently, different targets for duration, contents and general principles for training in vascular surgery have been set. Although in the past this may not have been a problem, the unification of countries in the European Community (EC), at present known as the European Union (EU), has changed this perspective because there is increasing impetus towards a mutual recognition of trade and education between member states. In 1975, EC directive 75/362 was adopted, which insured 'freedom of migration' for medical doctors along with many other professional trades (Publications of the European Communities no. L167, 30-6-1975, p. 1). This directive implicated that certificates, diplomas and other documents issued by the national competent authorities proving medical qualification allowed physicians to practice in any EU country. In order to make this law practical it seems essential that specialist training programmes throughout the EU should conform to certain agreed basic standards. The objective of this article is to present an overview on the current pattern of vascular surgical training in Europe. In addition, the structures that were established during the recent years to promote uniformly high standards of training in vascular surgery throughout the EU will be discussed.

Education, Medical, Continuing↗

Role of dobutamine stress echocardiography for preoperative cardiac risk assessment before major vascular surgery: a diagnostic tool comes of age.

BACKGROUND: Cardiac complications are a major cause for perioperative mortality and morbidity. Also, the presence and severity of underlying coronary artery disease (CAD) determine long-term prognosis after successful surgery. AIM: This overview evaluates the additional value of dobutamine stress echocardiography (DSE) to common clinical cardiac risk factors and other noninvasive cardiac imaging modalities for perioperative and late cardiac prognosis. RESULTS: DSE provides theattending physician with preoperative prognostic information for perioperative and long-term prognosis for cardiac events. It also enables the selection of high risk patients for evaluation of cardiac risk reduction therapies. CONCLUSIONS: DSE is a useful tool for preoperative cardiac risk evaluation in addition to common clinical cardiac risk factors.

Cardiotonic Agents↗

Technical data and complications of spinal cord stimulation: data from a randomized trial on critical limb ischemia.

This study was done to evaluate the effect of spinal cord stimulation (SCS) on critical limb ischemia and to report technical problems and complications. One hundred and twenty patients with critical limb ischemia were eligible for randomization between medical treatment and medical treatment plus SCS. Sixty received a spinal cord stimulator (Itrel II; Medtronic, Minneapolis, Minn., USA). Primary outcome measures were limb salvage and pain relief. The mean pain reduction in both treatment groups was 50% (from 5 to 2.5 on the visual analog scale). The 2-year limb survival was 52% (SCS) versus 46% (standard treatment; p = 0.47). The number of patients undergoing major amputations in the SCS group with intermediate TcpO2 values was half of that in the standard group (14 vs. 28; 24 vs. 48%; p = 0.17). Implantation was successful in 51 patients. Technical problems such as loss of stimulation due to lead displacement occurred in 13 patients (22%), local infection at the site of implantation occurred in 3 patients (5%), resulting in a total complication rate of 27%. Premature depletion of the battery occurred within 2 years in 3 patients (5%). There were no lead fractures, epidural infections, hematoma or cerebrospinal fluid leakage. Training of physicians and better reliability of the hardware should reduce the frequency of technical problems. Lead displacement remains the major technical problem. The search for prognostic factors of limb salvage is important. One microcirculatory measurement (TcpO2) seems to have a prognostic value, which remains to be described more precisely.

Aged↗

Vascular response in the femoropopliteal segment after implantation of an ePTFE balloon-expandable endovascular graft: an intravascular ultrasound study.

PURPOSE: To use intravascular ultrasound (IVUS) to document changes in vascular dimensions after placement of a balloon-expandable endograft. METHODS: Thirteen patients (9 men; mean age 62 years, range 47-75) treated with an investigational polytetrafluoroethylene endograft for obstructive disease of the femoropopliteal segment were studied with IVUS immediately after endograft implantation and at follow-up. Corresponding IVUS cross sections were analyzed for changes in lumen, vessel, and plaque areas seen inside the endograft, in the anastomotic segment, and in the remote arterial segment. RESULTS: A mean 6-month (range 1.5-9) follow-up was completed in 12 patients. Matched IVUS cross sections derived from within the endograft (n = 12) and at the endograft edges (n = 23) showed no change in lumen area (LA) in 17, reduction in 11, and dilatation in 7. Median changes within the endograft (+3%) were not significant (p = 0.28) and no neointima was found. Cross sections obtained at the anastomotic segment revealed a significant increase in LA (85%, p < 0.001), which was associated with a significant increase in both vessel area (VA) (42%, p < 0.001) and plaque area (PLA) (15%, p = 0.003) area. In the remote arterial segment, the change in LA was minimal (6%, p = 0.07), as were changes in the VA (9%, p = 0.04) and PLA (10%, p = 0.07). CONCLUSIONS: Following endograft placement, luminal changes within the endograft, at the endograft edges, and at the remote arterial segments were minimal. Intimal hyperplasia was not observed in the endograft. The distinct LA increase at the anastomotic segments was determined by the extent of VA and PLA change.

Aged↗

Endovascular repair of an extracranial internal carotid artery aneurysm complicated by heparin-induced thrombocytopenia and thrombosis.

PURPOSE: To report the endovascular treatment of a symptomatic extracranial internal carotid artery (ICA) aneurysm that was complicated by heparin-induced thrombocytopenia and thrombosis. METHODS AND RESULTS: After undergoing a coronary artery bypass graft procedure, a patient was diagnosed with a symptomatic, 3.5-cm ICA aneurysm by computed tomography and angiography. Via a semiclosed access, an Enduring vascular graft was inserted under controlled back bleeding from the ICA. The patient was recovering uneventfully when routine duplex scanning on the fifth postoperative day suggested multiple thrombi within the graft, which was confirmed by arteriography. Thrombectomy and local fibrinolysis were performed; however, the graft occluded the next day without causing neurological symptoms. Heparin-induced thrombocytopenia was diagnosed by enzyme-linked immunosorbent assay. CONCLUSIONS: Endovascular repair of high cervical extracranial ICA aneurysms is feasible, and protection against intracerebral embolization can be achieved using a semiclosed technique with controlled back bleeding from the ICA during endograft deployment. However, multiple thrombi or thrombotic occlusion during the postoperative period, particularly in a patient already sensitized to heparin, should direct attention toward possible heparin-induced thrombocytopenia.

Aged↗

The effect of bisoprolol on perioperative mortality and myocardial infarction in high-risk patients undergoing vascular surgery. Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group.

BACKGROUND: Cardiovascular complications are the most important causes of perioperative morbidity and mortality among patients undergoing major vascular surgery. METHODS: We performed a randomized, multicenter trial to assess the effect of perioperative blockade of beta-adrenergic receptors on the incidence of death from cardiac causes and nonfatal myocardial infarction within 30 days after major vascular surgery in patients at high risk for these events. High-risk patients were identified by the presence of both clinical risk factors and positive results on dobutamine echocardiography. Eligible patients were randomly assigned to receive standard perioperative care or standard care plus perioperative beta-blockade with bisoprolol. RESULTS: A total of 1351 patients were screened, and 846 were found to have one or more cardiac risk factors. Of these 846 patients, 173 had positive results on dobutamine echocardiography. Fifty-nine patients were randomly assigned to receive bisoprolol, and 53 to receive standard care. Fifty-three patients were excluded from randomization because they were already taking a beta-blocker, and eight were excluded because they had extensive wall-motion abnormalities either at rest or during stress testing. Two patients in the bisoprolol group died of cardiac causes (3.4 percent), as compared with nine patients in the standard-care group (17 percent, P=0.02). Nonfatal myocardial infarction occurred in nine patients given standard care only (17 percent) and in none of those given standard care plus bisoprolol (P<0.001). Thus, the primary study end point of death from cardiac causes or nonfatal myocardial infarction occurred in 2 patients in the bisoprolol group (3.4 percent) and 18 patients in the standard-care group (34 percent, P<0.001). CONCLUSIONS: Bisoprolol reduces the perioperative incidence of death from cardiac causes and nonfatal myocardial infarction in high-risk patients who are undergoing major vascular surgery.

Adrenergic beta-Antagonists↗

Spinal-cord stimulation in critical limb ischaemia: a randomised trial. ESES Study Group.

BACKGROUND: For patients with critical limb ischaemia, spinal-cord stimulation has been advocated for the treatment of ischaemic pain and the prevention of amputation. We compared the efficacy of the addition of spinal-cord stimulation to best medical treatment in a randomised controlled trial. METHODS: 120 patients with critical limb ischaemia not suitable for vascular reconstruction were randomly assigned either spinal-cord stimulation in addition to best medical treatment or best medical treatment alone. Primary outcomes were mortality and amputation. The primary endpoint was limb survival at 2 years. FINDINGS: The mean (SD) age of the patients was 72.6 years (10.3). Median (IQR) follow-up was 605 days (244-1171). 40 (67%) of 60 patients in the spinal-cord-stimulator group and 41 (68%) of 60 patients in the standard group were alive at the end of the study, (p=0.96). There were 25 major amputations in the spinal-cord-stimulator group and 29 in the standard group, (p=0.47). The hazard ratio for survival at 2 years without major amputation in the spinal-cord stimulation group compared with the standard group was 0.96 (95% CI 0.61-1.51). INTERPRETATION: Spinal-cord-stimulation in addition to best medical care does not prevent amputation in patients with critical limb ischaemia.

Aged↗

Endovascular stent-grafts for aneurysms of the femoral and popliteal arteries.

Our objective was to investigate the preliminary use of endovascular stent-grafts for the treatment of femoropopliteal artery aneurysm. Ten patients with an aneurysm of the femoropopliteal artery referred for endovascular treatment were investigated. The series consisted of patients with a true aneurysm of the superficial femoral artery (n = 2); a true aneurysm of the popliteal artery (n = 4); an aneurysmal dilatation of a Biograft bypass (n = 2); a false aneurysm of the superficial femoral aneurysm (n = 1); and a false aneurysm of a composite bypass (n = 1). In 8 of the 10 patients the stent-graft was composed of one or more Palmaz stents sutured to an ePTFE tube graft; in the other 2 patients a venous covering was used in combination with Palmaz stents. The procedure was guided by angiography and intravascular ultrasound. The results of our investigation showed that endovascular stent-grafting of aneurysms of the femoropopliteal artery is a feasible but experimental technique that should be restricted to a selected group of patients.

Aged↗

Accurate assessment of abdominal aortic aneurysm with intravascular ultrasound scanning: validation with computed tomographic angiography.

PURPOSE: The purpose of this study was to assess the accuracy of intravascular ultrasound (IVUS) parameters of abdominal aortic aneurysm, used for endovascular grafting, in comparison with computed tomographic angiography (CTA). METHODS: This study was designed as a descriptive study. Between March 1997 and March 1998, 16 patients with abdominal aortic aneurysms were studied with angiography, IVUS (12.5 MHz), and CTA. The length of the aneurysm and the length and lumen diameter of the proximal and distal neck obtained with IVUS were compared with the data obtained with CTA. The measurements with IVUS were repeated by a second observer to assess the reproducibility. Tomographic IVUS images were reconstructed into a longitudinal format. RESULTS: IVUS results identified 31 of 32 renal arteries and four of five accessory renal arteries. A comparison of the length measurements of the aneurysm and the proximal and distal neck obtained with IVUS and CTA revealed a correlation of 0.99 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate the length as compared with the CTA results (0.48 +/- 0.52 cm; P <.001). A comparison of the lumen diameter measurements of the proximal and distal neck derived from IVUS and CTA showed a correlation of 0.93 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate aneurysm neck diameter as compared with CTA results (0.68 +/- 1.76 mm; P =.006). Interobserver agreement of IVUS length and diameter measurements showed a good correlation (r = 1.0; P <.001), with coefficients of variation of 3% and 2%, respectively, and no significant differences (0.0 +/- 0.16 cm and 0.06 +/- 0.36 mm, respectively). The longitudinal IVUS images displayed the important vascular structures and improved the spatial insight in aneurysmal anatomy. CONCLUSION: Intravascular ultrasound scanning results provided accurate and reproducible measurements of abdominal aortic aneurysm. The longitudinal reconstruction of IVUS images provided additional knowledge on the anatomy of the aneurysm and its proximal and distal neck.

Adult↗

Is organ ischaemia a determinant of the outcome of operations for suprarenal aortic aneurysms?

OBJECTIVE: To find out if morbidity and mortality after thoracoabdominal approaches for suprarenal aortic aneurysms are related to the duration of organ ischaemia. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. SUBJECTS: 72 operations for suprarenal aortic aneurysms. MAIN OUTCOME MEASURES: Duration of organ ischaemia, morbidity and mortality. RESULTS: There were 72 patients with 3 group A (Crawford type III), 10 group B (Crawford type IV), 37 group C (supracoeliac), and 22 group D (suprarenal) aneurysms. Median duration of ischaemia was 57 minutes for both the spinal cord and the mesenteric arteries, and 59 and 63 minutes for the right and left renal arteries, respectively. There were 52 major complications in 33 patients. Mesenteric ischaemia of longer than 60 minutes was associated with a significant higher complication rate (21/32, 66% compared with 13/40, 33%, p = 0.01). Spinal cord ischaemia of longer than 60 minutes was not associated with a significantly increased incidence of paraplegia (2/40 compared with 6/32, p = 0.13). CONCLUSIONS: We conclude that with surgery for suprarenal aneurysms a significant higher complication rate is noted with increased duration of mesenteric ischaemia.

Aged↗

Selecting subjects for ultrasonographic screening for aneurysms of the abdominal aorta: four different strategies.

BACKGROUND: We studied whether the effectiveness of ultrasound screening for abdominal aortic aneurysms could be increased by preselecting high-risk subjects, based on the presence of risk indicators for the disease. METHODS: In a population-based screening programme for abdominal aortic aneurysms among 5328 subjects living in Rotterdam, The Netherlands, we studied four different strategies to select subjects for ultrasound screening of the abdominal aorta, based on risk indicators for abdominal aortic aneurysm disease. Risk indicators used in each strategy were entered in a logistic regression model to predict the probability of an individual having an abdominal aortic aneurysm. Using several cutoff values for the probability of a subject having an aneurysm for each strategy, we estimated the proportion of subjects that should be referred for ultrasound screening and the proportion of aneurysms that would be diagnosed by each strategy (sensitivity). RESULTS: When a probability of 1.5% of having an aneurysm is chosen as the cutoff point above which ultrasound screening is indicated, the proportion of subjects that would be referred for screening ranged from 36% (first strategy) to approximately 50% (other strategies), while 80% (first strategy) to approximately 94% (other three strategies) of all aneurysms would be detected. CONCLUSION: Effectiveness in screening for abdominal aortic aneurysms can be increased by selecting subjects by means of a short medical questionnaire, filled out by the screening candidates, including questions on medical history.

Aged↗

Intravascular ultrasound in endovascular stent-grafts for peripheral aneurysm: a clinical study.

PURPOSE: To evaluate the potential diagnostic information of intraprocedural intravascular ultrasound (IVUS) in patients undergoing endovascular stent-grafting for peripheral aneurysm. METHODS: IVUS was used in 17 patients preprocedurally to measure the diameter of the proximal and distal neck and the length of the aneurysm. Balloon and stent-graft sizes were selected based on these measurements. Following stent-graft deployment, angiography and IVUS were used to document stent apposition and the configuration and diameter of the stent-graft. RESULTS: Stent-graft insertion was considered successful in 8 patients based on angiography and IVUS images. In 9 others, both imaging modalities showed inadequate results, necessitating 12 additional procedures: balloon angioplasty for stent-graft stenosis (2) and inadequate stent-graft apposition (1); an additional stent-graft (4); an extra stent (1); thrombectomy (2); and conversion (2) for inadequate stent-graft position and a graft rupture. In these patients, intraprocedural IVUS was superiorto angiography in contributing vital information to aid in the selection of the additional interventions. CONCLUSIONS: During management of peripheral aneurysms with endovascular stent-grafts, IVUS monitoring was a useful adjunct when the initial procedure was unsatisfactory and/ or when intraprocedural angiographic studies were inconclusive.

Adult↗

Sustained prognostic value of dobutamine stress echocardiography for late cardiac events after major noncardiac vascular surgery.

BACKGROUND: Late cardiac events after major noncardiac vascular surgery are an important cause of morbidity and mortality. We studied the prognostic value of preoperative dobutamine stress echocardiography, relative to clinical risk assessment, in predicting late cardiac events. METHODS AND RESULTS: Three hundred sixteen patients undergoing major vascular surgery were studied. All patients underwent clinical evaluation for the presence of cardiac risk factors (smoking, hypertension, angina, diabetes, history of heart failure, previous infarction, and age > 70 years) and dobutamine stress echocardiography. Left ventricular wall motion was evaluated at rest, and the extent and severity of stress-induced new wall motion abnormalities were quantified. The heart rate threshold at which new wall motion abnormalities occurred was noted. Patients were followed perioperatively and for 19 +/- 11 months postoperatively, and the occurrence of cardiac events was noted. Univariate and multivariate Cox proportional hazards regression models were used to identify predictors of late cardiac events. Thirty-two cardiac events occurred (11 cardiac deaths, 11 nonfatal myocardial infarctions, and 10 incidents of unstable angina). By multivariate regression analysis, the occurrence of extensive (three or more segments) or limited (one or two segments) stress-induced new wall motion abnormalities and previous infarction independently predicted late cardiac events, elevating the risk by 6.5-, 2.9-, and 3.8-fold, respectively. The severity of ischemia during stress and the heart rate threshold for ischemia were not independently predictive. CONCLUSIONS: Patients with a history of myocardial infarction or stress-induced ischemia have a high risk of fatal and nonfatal cardiac events after vascular surgery. Patients with both a history of infarction and extensive stress-induced ischemia are at especially high risk and deserve intensive management.

Adult↗

Endoscopic versus open subfascial division of incompetent perforating veins in the treatment of venous leg ulceration: a randomized trial.

PURPOSE: Subfascial division of incompetent perforating veins plays an important role in the surgical treatment of patients with venous ulceration of the lower leg. To minimize the high incidence of postoperative wound complications after open exploration, endoscopic approaches have recently been developed. We carried out a prospective, randomized comparison of open and endoscopic treatment of these patients that was aimed at ulcer healing and postoperative wound complications. METHODS: Patients with current venous ulceration on the medial side of the lower leg were randomly allocated to open exploration by the modified Linton approach or endoscopic exploration by use of a mediastinoscope. RESULTS: Thirty-nine patients were randomized, 19 to open exploration and 20 to endoscopic exploration. The incidence of wound infections after open exploration was 53%, compared with 0% in the endoscopic group (p < 0.001). Patients in the open group needed longer hospital stays (mean, 7 days; range, 3 to 39 days) than patients in the endoscopic group (mean, 4 days; range, 2 to 6 days; p = 0.001). Four months after operation, the ulcers of 17 patients (90%) in the open group and 17 patients (85%) in the endoscopic group had healed. During a mean follow-up of 21 months (range, 16 to 29 months), no recurrences were noticed in either group. CONCLUSIONS: Endoscopic division of incompetent perforating veins is equally as effective as open surgical exploration for the treatment of venous ulceration of the lower leg but leads to significantly fewer wound healing complications. Endoscopic division is therefore the preferred method.

Adult↗

Validation of duplex ultrasonography in detecting competent and incompetent perforating veins in patients with venous ulceration of the lower leg.

PURPOSE: Incompetent perforating veins play an important role in the etiologic mechanism of venous ulceration and recurrent varicose veins. The anatomic and functional status of the venous system can be evaluated by duplex ultrasonography. To determine the value of this technique in the identification of competent and incompetent perforating veins, a prospective study was performed. METHODS: In patients who underwent subfascial exploration for venous ulceration of the lower leg, the preoperative findings of duplex ultrasonography were compared with the findings at surgical exploration. RESULTS: In 20 consecutive patients, 42 incompetent and 8 competent perforating veins were detected by duplex ultrasonography. During operation the location of all 50 perforating veins appeared to be predicted correctly. Eleven additional perforating veins that had not been detected by duplex ultrasonography were found during operation. The sensitivity and specificity of duplex ultrasonography in predicting the site of perforating veins at the medial side of the lower leg in our study were 79.2% and 100%, respectively, for incompetent perforating veins and 82% and 100%, respectively, for competent and incompetent perforating veins. CONCLUSION: These figures indicate that duplex-guided local exploration of the lower leg in patients with venous ulceration as a result of incompetent perforating veins would miss a substantial number of perforating veins, possibly leading to incomplete healing or recurrent ulceration.

Adult↗

Efficacy of subfascial endoscopy in eradicating perforating veins of the lower leg and its relation with venous ulcer healing.

PURPOSE: The purpose of this study was to investigate the efficacy of subfascial endoscopy by use of a mediastinoscope in the identification and ligation of incompetent perforating veins in patients with venous ulceration of the lower leg. METHODS: All patients who underwent subfascial endoscopy for venous ulceration between Jan. 1, 1994, and Mar. 1, 1995, at the Sint Franciscus Gasthuis in Rotterdam underwent duplex ultrasound scans of the lower leg before and 6 weeks after operation. The number and localization of the perforating veins on the mediodorsal side were compared with the findings during subfascial endoscopy. RESULTS: In 20 patients, preoperative duplex examination showed 46 incompetent and six competent perforating veins. During operation the site of 43 incompetent and all competent perforating veins was confirmed. Five additional perforating veins were found at operation (false-negatives). Postoperative duplex ultrasound scans showed six incompetent perforating veins (four persisting and two recurring perforating veins) in four patients, of which the ulcers did not heal in three. The ulcers of the other 17 patients healed. CONCLUSIONS: Subfascial endoscopy is an efficient technique in identifying incompetent perforating veins in patients with chronic ulceration of the lower leg. The persistence of incompetent perforating veins is related to failure of ulcer healing.

Adult↗