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R Balm

Publications and source records attributed to R Balm.

At least 19 recordsLinked to original sources

Interobserver variation of colour duplex scanning of the popliteal,tibial and pedal arteries.

OBJECTIVES: to determine interobserver variation in the measurement of Peak Systolic Velocity (PSV) and grading of disease by means of Duplex scanning (DS) in the popliteal, tibial and pedal arteries. DESIGN: prospective validation study. MATERIALS: twenty-four consecutive patients with severe claudication (n=6), ischaemic rest pain (n=11) and tissue loss (n=7). METHODS: two vascular technologists independently examined the popliteal, tibial and pedal arteries. The PSV was recorded in 15 arterial segments that were graded with B-mode and Doppler parameters as fully patent, severely diseased or occluded. Concordance in PSV recordings was expressed as intraclass correlation coefficients (ICC). Agreement in artery assessment was expressed as weighted kappa-values. RESULTS: the ICC for PSV measurements was 0.90 (95% CI, 0.86 to 0.93) within the popliteal and tibial arteries and 0.64 (95% CI, 0.37 to 0.81) within the pedal arteries. Agreement for grading disease was good within the popliteal and tibial arteries (kappa 0.66, 95% CI, 0.58 to 0.74), and moderate within the pedal arteries (kappa 0.54, 95% CI 0.33 to 0.74). The presence of diabetes or stage of disease did not influence interobserver agreement. CONCLUSION: interobserver agreement of DS is good within the popliteal and tibial arteries and moderate within the pedal arteries.

Aged↗

Interobserver variation in interpretation of arteriography and management of severe lower leg arterial disease.

OBJECTIVE: arteriography is the reference standard for the assessment of the lower leg arteries in patients with severe lower limb ischaemia. Interobserver variation in arteriography interpretation may cause disparities with non-invasive imaging modalities. We determined interobserver variation in lower leg artery assessment with intra-arterial digital subtraction angiography (IaDSA) and subsequent patient management. MATERIALS: iaDSA studies of patients evaluated for severe claudication (n =5) or critical ischaemia ( n =43). METHODS: arteriograms were independently judged by four observers. The popliteal and tibial arteries were graded as fully patent, severely diseased, occluded or non-diagnostic. The dorsalis pedis, common and deep plantar artery were graded as directly, indirectly or not filling the pedal arch or non-diagnostic. Agreement on grading arteries was expressed as kappa-values. Treatment plans (conservative, PTA, surgery, amputation, non-diagnostic) proposed by each observer based on clinical information and iaDSA were compared. RESULTS: the rate of non-diagnostic judgements ranged from 1% in the popliteal to 22% in the pedal arteries. Overall agreement was good for grading the popliteal arteries (kappa=0.64), moderate for the tibial (kappa=0.47--0.54) and fair for the pedal arteries (kappa=0.39). Agreement was good to excellent for grading occluded or fully patent popliteal and tibial artery segments, and fair to moderate for grading severe disease. In 57% of cases at least 3 observers proposed identical treatment, which indicates fair overall agreement (kappa=0.33). CONCLUSION: interobserver agreement on iaDSA is good to determine occluded or fully patent popliteal or tibial arteries, but not for severe disease. This should be taken into account when other diagnostic modalities are compared with iaDSA. Evaluation of diagnostic modalities as concordance in treatment plans is flawed by interindividual variation.

Adult↗

Duplex scanning allows selective use of arteriography in the management of patients with severe lower leg arterial disease.

PURPOSE: Until April 1997 we routinely performed intra-arterial digital subtraction angiography (iaDSA) in all patients with severe lower leg ischemia requiring intervention. After a comparative study of duplex scanning (DS), pulsegenerated runoff, and iaDSA of the lower leg arteries, we postulated that management could be based on DS/pulse-generated runoff in 59% of patients. We prospectively evaluated the safety of such a noninvasive workup strategy. METHODS: All consecutive patients referred with severe lower leg ischemia between April 1997 and September 1998 were eligible. Management was based on DS with iaDSA being performed only on indication. Complications within 30 days and 12- and 24-month patency, survival, and limb salvage rates were recorded and compared with historical controls. RESULTS: A total of 125 limbs in 114 patients were evaluated (74% rest pain or tissue loss). In 97 (78%) of 125 limbs, management was based on DS. It comprised conservative treatment (n = 33, 0% after iaDSA), percutaneous transluminal angioplasty (n = 25, 16% iaDSA), femoropopliteal bypass graft (n = 29, 17% iaDSA), femorotibial bypass graft (n = 29, 62% iaDSA), and other surgical procedures (n = 8, 4% iaDSA). Overall, the mortality within 30 days was 4% (5/114), and 2-year survival was 83%. Two-year primary and secondary patency and limb salvage rates were 75%, 93%, and 93% after a femoropopliteal bypass operation, respectively. One-year primary and secondary patency and limb salvage rates were 35%, 73%, and 74%, respectively, after a femorocrural bypass operation. There were no differences in patient characteristics, indication for specific treatment, and immediate and intermediate term outcome between the study and reference population. CONCLUSION: In a vascular unit with wide expertise in DS of the lower leg arteries, management of patients with severe lower leg ischemia can be based on DS in most patients without negative effects on clinical outcome within 30 days and at 2-years' follow-up.

Adult↗

Ischemic transverse myelopathy after endovascular repair of a thoracic aortic aneurysm.

PURPOSE: To report a dramatic complication after endovascular repair of a descending thoracic aortic aneurysm (TAA) and to present a classification system and possible methods to avoid spinal cord ischemia. CASE REPORT: A 48-year-old man with a descending TAA between T5 and T9 was treated with endovascular stent-grafts. Fourteen hours after the operation, the patient developed partial transverse myelopathy at level T10. During emergency conversion to open surgery and implantation of a conventional tube graft, 3 intercostal arteries that had been covered by the stent-graft were revascularized. Postoperatively, the neurological deficit improved, and the patient was able to walk again. Methods to predict and possibly prevent the induction of spinal cord ischemia after endovascular repair of TAA are suggested. CONCLUSIONS: Endovascular repair of TAA may induce spinal cord ischemia; pre- and intraoperative assessment of involved intercostal arteries should be performed.

Aortic Aneurysm, Thoracic↗

Postpolypectomy lower GI bleeding: descriptive analysis.

BACKGROUND: Postpolypectomy hemorrhage may warrant intensive care monitoring, transfusions, and surgery. We sought factors predicting significant bleeding requiring blood transfusion and the benefits of critical care monitoring. METHODS: Patients with postpolypectomy bleeding between April 1989 and November 1996 were identified from a comprehensive GI bleeding database. Data included age, gender, medical history, medications, polyp characteristics, and polypectomy technique. Outcomes assessed included bleeding cessation, transfusion requirements, recurrent bleeding, length of stay, and death. RESULTS: There were 83 patients with a median age of 73 years (range 18 to 88 years; 56 men, 27 women). Comorbid conditions were common (71.1% cardiovascular, 43.4% musculoskeletal, 14.5% hematologic, 6.0% renal). Within 3 days of presentation, 32.5% had taken aspirin, 10.8% nonsteroidal anti-inflammatory drugs, 12.0% warfarin, and 12.0% corticosteroids; and within 1 day, 10.8% intravenous heparin, 7.2% subcutaneous heparin, and 7.2% dipyridamole. Fifty-seven percent of patients were hemodynamically stable. Sessile cecal polyps greater than 2 cm in diameter bled more commonly. The median number of units transfused was equal between critical care and noncritical care patients. Using age in the logistic regression model, no other variable was predictive of transfusion. Eighty patients (96.4%) received endoscopic therapy, 1 required embolization and 2 hemicolectomy. There was no significant difference in outcomes for patients managed in an intensive care unit versus a general medical floor. CONCLUSIONS: Postpolypectomy bleeding appears to have a predictable presentation and outcome. Advanced age seems to be predictive of transfusion requirement. Patient monitoring in an intensive care setting is not absolutely necessary.

Adolescent↗

Reduced renal failure following thoracoabdominal aortic aneurysm repair by selective perfusion.

OBJECTIVES: Renal failure and visceral ischemia are feared complications following thoracoabdominal aortic aneurysm (TAAA) repair, significantly contributing to mortality. This prospective study describes volume- and pressure-controlled perfusion of the renal and visceral arteries during TAAA surgery. METHODS: In 73 consecutive patients (mean age 59 years), TAAA repair (27 type I, 28 type II, 8 type III and 10 type IV) was performed, using retrograde and selective organ perfusion. Sixteen patients had impaired renal function with blood creatinine higher than 100 mmol/l. During the thoracic part of the procedure, the mean distal aortic pressure was kept above 60 mm Hg by means of left-heart bypass. After opening the abdominal aorta, the renal and visceral arteries were individually perfused by means of perfusion catheters (9 French) in the first 33 patients (group I). Volume flow through each catheter was assessed with ultrasound flow meters and maintained at least at 60 ml/min. In addition to volume flow measurements, catheters with pressure sensors were used in the last 40 patients (group II), allowing pressure-controlled selective perfusion. The extent of the aneurysm was comparable in both groups. RESULTS: Mean cross-clamp time for the thoracic part was 46 min, including proximal anastomosis and reattachment of intercostal arteries. Mean cross-clamp time for the abdominal part was 74 min, including re-implantation of intestinal and renal arteries and selective dacron grafts to the celiac-axis arteries (n = 5), superior mesenteric arteries (n = 8) and renal arteries (n = 25), through which the catheters guaranteed continuous perfusion during the time the anastomosis was performed. Urine output was uninterrupted in all patients, irrespective of cross-clamp time. In group I, one patient (3%) developed renal failure and three patients (9%) required temporary peritoneal dialysis. In group II, no patients developed renal failure and two patients (5%) required temporary peritoneal dialysis. Thirteen patients with pre-existing renal impairment did not deteriorate. No patients developed visceral ischemia or multiple-organ failure. Total in-hospital mortality was 6/73 (8%) and was related to cardiopulmonary complications. CONCLUSIONS: Renal and visceral ischemia can be reduced significantly by continuous perfusion during cross-clamping in TAAA repair. Not only sufficient volume flow but also adequate arterial pressure appears to be essential in maintaining renal function.

Aortic Aneurysm, Abdominal↗

Aortoiliac reconstructive surgery based upon the results of duplex scanning.

OBJECTIVE: To evaluate whether duplex scanning can replace angiography in patients operated for aortoiliac obstructive disease. DESIGN: Retrospective. MATERIALS AND METHODS: Between January 1995 and October 1996, 44 patients underwent vascular surgery of the aortoiliac tract. The study population was divided into two groups; patients operated upon the results of duplex scanning only and patients who also underwent angiography prior to surgery. The additional value of angiography and the differences between both groups concerning unexpected peroperative findings, early postoperative failures and the need for additional radiological or surgical interventions in the first three postoperative months were studied. RESULTS: Duplex scan group: 22 patients were operated upon the results of duplex scanning only. In two patients surgical strategy had to be changed. Early postoperative graft occlusion occurred in one case. A haemodynamically significant graft stenosis within 3 months of surgery occurred in one patient. Duplex/angiography group: 22 patients underwent both duplex scanning and angiography. Six patients underwent diagnostic angiography after failed duplex scanning. In 10 patients angiography was part of percutaneous transluminal angioplasty prior to surgery. In six patients angiograms were performed after successful duplex scanning. Angiography failed in two patients and added information in four of 16 patients. Unexpected findings at operation occurred in four patients. Graft stenosis within 3 months was detected in three patients. CONCLUSION: After successful duplex scanning information obtained by angiography has only a limited impact on therapeutic decision-making. In the majority of patients vascular reconstructive surgery of aortoiliac arteries can be planned based on duplex scanning only.

Adult↗

Computed tomographic angiographic imaging of abdominal aortic aneurysms: implications for transfemoral endovascular aneurysm management.

PURPOSE: To describe anatomic features pertinent to patient selection and graft design for transfemoral endovascular aneurysm management (TEAM) of the infrarenal aorta using computed tomographic (CT) angiography. METHODS: A prospective noncomparative analysis of 102 spiral CT scans of the abdominal aorta of patients with abdominal aortic aneurysms was performed. From the original CT data set, slices were reconstructed perpendicular to the vessel axis (central lumen line) at a 10 mm interval. In these reconstructed slices, diameter measurements were performed. Vessel length was measured along the central lumen line. In each patient possibilities for TEAM were analyzed. RESULTS: Because of technical reasons, 36 scans were excluded from the analysis. Of the remaining 66 patients, 18 could potentially be treated with a bifurcated endovascular device. The infrarenal aortic diameter-to-iliac artery diameter ratio was less than 2 in most patients. The vessel segments judged to be adequate for endovascular graft anchoring had a noncylindrical shape in the majority of cases. CONCLUSION: Only a minority of patients with abdominal aortic aneurysms can at this stage be treated with an endovascular graft. The ideal endovascular graft should be a combination of rigid and flexible components. The proximal and distal attachment systems should have some flexibility with an intrinsic maximum diameter while the midsection of the graft can be relatively rigid.

Adult↗

Use of spiral computed tomographic angiography in monitoring abdominal aortic aneurysms after transfemoral endovascular repair.

Transfemoral endovascular repair of abdominal aortic aneurysms has proved to be technically feasible in a selected group of patients. However, long-term efficacy has not been proved. Graft performance after implantation can be monitored by a single imaging technique: spiral computed tomographic angiography. With this technique, the parameters for continuing clinical success of the procedure-graft patency, endoleaks, graft migration, attachment site diameter, attachment system failure, and aneurysm diameter-can be monitored. Only in selected cases will an additional imaging technique be necessary.

Aortic Aneurysm, Abdominal↗

Early experience with transfemoral endovascular aneurysm management (TEAM) in the treatment of aortic aneurysms.

OBJECTIVES: To evaluate the early experience with transfemoral endovascular aortic aneurysm management using the Endovascular Grafting System. DESIGN: Multi-centre prospective evaluation of the implantation procedure and early results (median follow-up 153 days). SETTING: Department of Surgery, University Hospital Utrecht, The Netherlands; Department of Surgery, University of Sydney, Australia; University of Leicester School of Medicine, Leicester, U.K., Department of Surgery, Karolinska Hospital, Stockholm, Sweden and Nuffield Department of Surgery, University of Oxford, John Radcliffe Hospital; Oxford, U.K. MATERIALS: 31 consecutive patients treated in 13 months. CHIEF OUTCOME MEASUREMENTS: Peri and postoperative morbidity and mortality in accordance with the recommendations of the Ad Hoc Committee on Reporting Standards. MAIN RESULTS: Graft placement was initially successful in all 31 patients. In one patient the endograft had to be replaced by a standard aortic tube graft because of extra graft flow in the aneurysm sac, and complaints of back pain. One patient died from multiple organ failure, 11 days after the operation. In three patients five severe adverse events were recorded. Breaks of the attachment system were encountered in two patients. These failures did not have severe clinical consequences for individual patients. CONCLUSIONS: Transfemoral Endovascular Aneurysm Management is a technically demanding procedure that requires special training in both catheter and surgical techniques. The potential for less operative morbidity when compared to conventional surgery and the prospect of technical improvements in graft and introduction system design will make TEAM an important tool in aneurysm management in the near future.

Aged↗

CT-angiography of abdominal aortic aneurysms after transfemoral endovascular aneurysm management.

OBJECTIVE: To evaluate short-term effect of Transfemoral Endovascular Aneurysm Management (TEAM) on aortic diameters and volumes after aneurysm exclusion, using CT-angiography. DESIGN: Analysis of preoperative, 1 week postoperative and 6 months postoperative CT measurements. SETTING: University Hospital. MATERIALS: Nine patients treated with an endovascular tube prosthesis. CHIEF OUTCOME MEASURES: True cross-sectional diameters of the aorta and the aneurysm, volume of the infrarenal aortic lumen, of the thrombus and of the iliac arteries and length of the aorta and of the endovascular prosthesis. MAIN RESULTS: CT-angiography detected shrinkage of the aneurysm in seven patients. Aneurysm growth was observed in one patient with persistent flow outside the graft and in one patient with fully thrombosed aneurysm sac. In the two patients with increasing thrombus volume, the volume of the aortic lumen decreased. CONCLUSIONS: Although successful aneurysm exclusion can be confirmed by maximum aneurysm diameter measurement, changes in aortic lumen volume and thrombus volume may be more appropriate to discriminate successful from failed exclusion.

Aged↗

Cerebral metabolism of patients with stenosis of the internal carotid artery before and after endarterectomy.

Occlusion or severe stenosis, with a reduction in the diameter of more than 70% of the extracranial arteries may lead to hpoperfusion of the brain with an increased risk of cerebral infarction. The aim of this study was to investigate whether endarterectomy of stenosed internal carotid arteries leads to alternations in cerebral metabolism in regions in which no infarcts were visible with magnetic resonance imaging (MRI). We studied 10 healthy control subjects and 20 patients with transient or nondisabling cerebral ischemia with MRI and 1H magnetic resonance spectroscopic imaging. All patients underwent carotid endarterectomy. Patients were examined 1 week before and 3-6 months after carotid endarterectomy. The N-acetyl aspartate (NAA)/choline ratio in the symptomatic hemisphere before endarterectomy (2.29 +/- 0.42) was significantly (p < 0.001) lower than for control subjects (3.18 +/- 0.32). In five of the patients lactate was detected preoperatively in regions that were not infarcted. The NAA/choline ratio in the symptomatic hemisphere of these five patients did not increase significantly after endarterectomy (1.99 +/- 0.22 vs. 2.23 +/- 0.48). The NAA/choline ratio in patients without lactate preoperatively increased significantly (p < 0.01) after endarterectomy to a normal level (from 2.39 +/- 0.42 to 2.92 +/- 0.52). These results indicate that the presence of cerebral lactate may predict whether the NAA/choline ratio increases after carotid endarterectomy.

Aged↗

The risk of withdrawing chronic anticoagulation because of acute GI bleeding.

OBJECTIVE: We sought evidence for thromboembolic sequelae after the transient withdrawal of chronic anti-coagulation because of acute GI bleeding. METHODS: Our Gastrointestinal Bleeding Team endoscopic database was reviewed over a 5-yr period to identify patients who underwent a transient withdrawal from chronic anticoagulation as a result of acute GI bleeding. Long term follow-up records were available for all study patients and were carefully scrutinized for any symptomatic thromboembolic events. RESULTS: Twenty-seven patients were included in the study, of which 17 (63%) were on chronic anticoagulation for prosthetic heart valves. Chronic anticoagulation was withheld for a median period of 3 days (range = 2-7 days) for patients with prosthetic heart valves and 7 days (range = 2-15 days) for patients on chronic anticoagulation for other indications. Over a median follow-up period of 8 months (range = 1-54 months), one patient developed documented lower extremity thromboembolism. CONCLUSIONS: We conclude that symptomatic thromboembolism can occur after the transient withdrawal of chronic anticoagulation for acute GI bleeding but that it does not occur frequently.

Acute Disease↗

[Treatment of an infrarenal aortic aneurysm using a transfemorally-placed endoprosthesis: initial results in 9 patients in The Netherlands].

OBJECTIVE: To describe the first experiences with transfemoral aortic endoprostheses for treatment of aortic aneurysms in the Netherlands. SETTING: University Hospital Utrecht, The Netherlands. METHOD: Patient selection was based on information presented on CT and angiography films. Only patients with an asymptomatic aneurysm and non-dilated aortic segments both distal from the renal arteries and proximal to the aortic bifurcation were selected. Of 71 patients screened only nine candidates were selected. RESULTS: The placement of the endoprosthesis was initially successful in all patients. The duration of the operation varied from 60 to 160 min. An intimal lesion of the common femoral artery occurred in one patient. In three cases leakage of contrast material outside the prosthesis but inside the aneurysm was seen on the postoperative CT angiogram. In one patient the endoprosthesis had to be replaced by a conventional aortic tube graft on the second postoperative day. After the procedure the patients stayed in hospital for another 3 to 20 days (median: 5). CONCLUSION: Endovascular treatment of infrarenal abdominal aneurysm is a promising technique. The main advantages to the patient are that laparotomy is not necessary and that the hospital stay is reduced.

Aged↗

Re-establishment of cerebral metabolism after carotid endarterectomy.

OBJECTIVES: The purpose of this study was to evaluate the metabolic changes that occur in the human brain in patients with a symptomatic carotid artery stenosis. MATERIALS AND METHODS: N-acetyl-aspartate (NAA), choline, creatine and lactate were measured both before, and 4 days after, carotid endarterectomy, by magnetic resonance spectroscopic imaging (MRSI). Eight controls and 16 patients were examined. MRI and MRSI studies were performed on a Philips Gyroscan S15 whole body system operating at 1.5 Tesla. 1H spectra were selected from regions in the centrum semi-ovale outside areas showing white matter hyper intensities on MRI. RESULTS: All patients showed a decrease of the NAA/choline and NAA/creatine ratio in the symptomatic hemisphere compared to the contralateral hemisphere and also compared to the controls. Lactate was present in some patients (5/16). After endarterectomy, the NAA/choline and NAA/creatine ratios increased significantly compared to the ratios preoperative. Lactate was absent or more than 50% reduced after the operation. MRSI showed metabolic changes in areas of the brain that did not show any abnormalities on MRI. CONCLUSIONS: There are marked changes in brain metabolism in the symptomatic hemisphere of patients with a severe carotid artery stenosis. These metabolic changes normalise four days after endarterectomy.

Aged↗

Cerebral metabolism of patients with stenosis or occlusion of the internal carotid artery. A 1H-MR spectroscopic imaging study.

BACKGROUND AND PURPOSE: Occlusion or severe stenosis of extracranial vessels may lead to hypoperfusion without overt infarction of brain tissue. The aim of this study was to investigate whether occlusion of the internal carotid artery or stenosis with reduction in diameter of more than 70% leads to altered cerebral metabolism in regions in which no infarcts are visible with magnetic resonance imaging. METHODS: We studied 10 control subjects and 55 patients with transient or nondisabling cerebral ischemia (25 patients with severe unilateral stenosis, 15 patients with unilateral occlusion, and 15 patients with bilateral severe stenosis or occlusion of the internal carotid artery). All subjects underwent magnetic resonance imaging and 1H magnetic resonance spectroscopic imaging. Cerebral metabolism was studied by assessing ratios of N-acetyl aspartate (NAA) to choline and to creatine as well as lactate from noninfarcted frontal, mesial, and parietal regions in the centrum semiovale in both hemispheres. RESULTS: All patients with unilateral stenosis or occlusion of the internal carotid artery had decreased NAA/choline ratios in noninfarcted areas in the hemisphere on the side of the stenosis or occlusion and normal NAA/choline ratios in the contralateral hemisphere. Patients with bilateral stenosis or occlusion had decreased NAA/choline ratios in both hemispheres. In one third of all patients, cerebral lactate was found in regions without abnormalities on magnetic resonance imaging. CONCLUSIONS: A severe reduction in the diameter of the internal carotid artery affects cerebral metabolism in regions that are not infarcted. These changes are reflected in a decreased NAA/choline ratio and a high incidence of cerebral lactate. These regions are probably at risk for infarction in the long term or if cerebral perfusion decreases further.

Aged↗

Spiral CT-angiography of the aorta.

AIMS: To determine whether the new technique of CT-angiography was accurate in displaying the complex anatomy of the aorta and its major branches. METHODS: Seventeen patients with a variety of aortic pathology were examined. Using a spiral CT-scanner a volumetric scan was made during injection of 150 cc of i.v. contrast. Depending on the chosen CT technique, a body volume with a length ranging between 25-100 cm could be examined in one 50 second spiral scan. On the resulting transverse slices vascular lumina and extent of thrombus were studied. Subsequently, the transverse slices were reconstructed in the coronal or sagittal plane in order to appreciate the craniocaudal relations of the vascular anatomy. Finally, three-dimensional reconstructions were made of vascular lumina and thrombus. RESULTS: In aortic aneurysms the extent of the aneurysmal dilatation and of the adherent thrombus could be accurately located relative to the origins of renal and visceral branches proximally, and iliac bifurcation distally. In cases of severe elongation, dissection or complex anatomy, a detailed preoperative insight into the individual anatomy could be obtained. The two-dimensional axial and multiplanar reconstructions offered excellent anatomic detail. The three-dimensional reconstructions, being based on a considerable data reduction, offered an efficient means of providing an overall view of complex anatomic relations. CONCLUSION: The advantage of CT-angiography is that, based on a single spiral scan, the vascular structures in the examined body volume can be displayed in any desired plane using multiplanar reconstructions. Alternatively, three-dimensional renderings can be created. The combination of multiplanar reconstructions and three-dimensional reconstructions makes CT-angiography an accurate technique for displaying even the most complex aortic anatomy.

Aortic Dissection↗