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J R Allenberg

Publications and source records attributed to J R Allenberg.

At least 19 recordsLinked to original sources
PubMed2007

[Metabolic syndrome and peripheral arterial occlusive disease as indicators for increased cardiovascular risk].

BACKGROUND AND AIMS: The usefulness of the metabolic syndrome (MetS) or a low ankle brachial index (ABI), respectively, to identify patients with high risk for cardiovascular events has repeatedly been postulated. However, robust data on the prevalence and prognosis of such patients are missing in the primary care setting. PATIENTS AND METHODS: In the prospective, non-interventional "German epidemiological trial on Ankle Brachial Index (getABI) at total of 6880 unselected patients > or = 65 years were observed by their General Practitioners over 3 years. Death and cardiovascular events were recorded. The definition of MetS was similar to the one of NCEP ATP III (National Cholesterol Education Program--Adult Treatment Panel III). ABI (ratio of the systolic blood pressures measured at the distal part of the calf and at the upper arm) was measured with Doppler sonography. Peripheral arterial disease (PAD) was defined as ABI <0.9 or peripheral revascularization/amputation owing to PAD. Survival analyses were conducted with a Cox proportional hazard model. Hazard rate ratios (HRR, 95 % confidence intervals, CI) were multvariate adjusted. RESULTS: The observation time for the total cohort was more than 20,000 patient years (PY). Cardiovascular mortality in patients with MetS (n = 3040, 44 %) compared to patients without MetS (n = 3795; 55 %) was doubled (8.5 vs. 4.0 per 1,000 PY; HRR: 2.0; CI 1.3 - 2.9). Concomitant presence of MetS and PAD (n = 651; 9.5 %) increased the mortality risk compared to patients without both conditions (n = 3194; 46.4 %) drastically (21.1 vs. 3.0 per 1000 PY; HRR: 5.7; CI: 3.5 - 9.4). Similar significant risk increases also were noted for all-cause mortality or a combined endpoint of mortality and vascular morbidity. Further, in lower ABI categories cardiovascular event rates increased. CONCLUSIONS: Patients with MetS carry a substantially increased risk of premature death, especially cardiovascular death, and therefore require intensive treatment of their risk factors. This holds especially true if concomitant PAD is present.

Aged↗
PubMed2006

[Surgical management of isolated iliac aneurysms].

Isolated iliac aneurysms (IIA) are uncommon lesions that require surgical repair to prevent rupture. The aim of this article is to give an update on the current surgical management of IIA. This report also evaluates the application of endovascular repair in IIA, based on a recent Pubmed search and on our own experience in the interventional field: Open reconstruction achieves good longterm results and still represents the golden standard in surgical treatment of IIA. Transluminally placed endovascular stent grafts can be successfully used to exclude isolated iliac aneurysms in selected high risk patients with suitable anatomy. A classification based on aneurysm morphology is useful for patient selection. The value of endovascular therapy has yet to be determined.

Adult↗
PubMed2006

Hybrid aortic procedures for endoluminal arch replacement in thoracic aneurysms and type B dissections.

The aim of this study was to report our clinical experience with and review current literature on endoluminal aortic hybrid techniques and to evaluate outcome in high-risk patients treated for complex aortic arch lesions combining conventional supra-aortic debranching bypasses with subsequent or staged thoracic endovascular grafting. Of 172 patients treated with thoracic endografts for different thoracic aortic pathologies within the last 8 years, the mid-aortic arch was involved in 25, i.e. at least the left common carotid artery had to be overstented and revascularized to provide a proper proximal landing zone. These debranching bypasses were performed as a simultaneous or a staged procedure. All patients were at high-risk and were excluded by cardiac surgeons as ineligible for conventional arch repair. After partial (n=16) or complete (n=9) supra-aortic transposition, 4 different commercially available endografts (80% TAG, WL Gore) were implanted transfemorally or via iliac conduit. Deployment success was 100% in 25 patients after simultaneous or staged supra-aortic transposition; in 32% an emergency procedure was performed due to contained rupture; in 36% more than 1 endograft system was implanted (2 in 20%, 3 in 8% und 4 in 8%). The overall perioperative thirty-day mortality was 5 of 25 (20%) due to interoperative proximal bare stent perforation (n=1), transfusion related acute lung injury (TRALI n=1), cardiac failure (n=1), embolic stroke (n=1) and pneumonia (n=1). The mean follow-up was 21 months. All endoleaks type I (n=3) were corrected with another endograft; the 2 endoleaks type II sealed spontaneously. The major adverse events were: prolonged ventilation in 5 (20%), temporary renal insufficiency with hemodialysis (n=2), bypass infection (n=1), without any complications (n=9). No cases of paraplegia were recorded. Hybrid aortic arch repair is technically challenging but feasible. This novel approach may be an alternative to standard open procedures in high-risk patients and emergency cases. However, the promising early results need to be confirmed by longer follow-up and larger series.

Aortic Dissection↗
PubMed2005

Do workshops improved the technical skill of vascular surgical trainees?

AIMS: Adjuncts to conventional surgical training are needed in order to address the reduction in working hours. This purpose of this study was to objectively assess the efficacy of workshop training on simulators. METHODS: Fifteen consecutive participants of the European Vascular Workshop in 2003 and 2004 were recruited to this study. Participants performed a proximal anastomosis on a commercially available abdominal aortic aneurysm simulator, were then given intensive training on sophisticated models for 3 days and re-assessed. Pre- and post-course procedures were videotaped and independently reviewed by three assessors (tapes were blinded and in random order). The operative end product was similarly assessed. Four measures of technical skill were used: generic skill, procedural skill; a five point technical rating of the anastomosis (assessed using validated rating scales) and procedure time. Non-parametric tests were used in the statistical analysis. RESULTS: The video assessment scores for aneurysm repair increased significantly following completion of the course (p=0.006 and p=0.004 for generic and procedural skill, respectively). End product assessment scores increased significantly post-course (p=0.001) and participants performed aneurysm repair faster following the course (p<0.05). Inter-observer reliability ranged from alpha=0.84-0.98 for the three rating scales pre- and post-course. CONCLUSION: Objective improvements in technical performance follow intensive workshop training. Participants' perform better, faster, and with an improved end product following the course. Such adjuncts to training play an important part in a focused integrated programme that addresses reduced work hours.

Anastomosis, Surgical↗
PubMed2004

The Stent-Supported Percutaneous Angioplasty of the Carotid Artery vs. Endarterectomy Trial.

The Stent-Supported Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy (SPACE) Trial is investigating if both treatment modalities are equivalent in the treatment of severe symptomatic carotid stenoses. Patients with symptomatic (transient ischaemic attack or minor stroke) stenosis (above 50% following the North American Symptomatic Endarterectomy Trial criteria) eligible for both methods can be recruited into this trial. The primary endpoint is the incidence of an ipsilateral stroke or death between randomisation and day 30 after treatment. Surgeons as well as the interventionalists have to demonstrate their expertise prior to participation in the trial. Funding is mostly by public institutions (Federal Ministry of Education and Research and German Research Foundation). An external monitoring is applied. Thirty-two centres are currently taking part in the SPACE Trial that has been running in Germany, Austria and Switzerland for 3 years, and they have been able to recruit a total of around 670 patients. The definitive results of this study cannot be expected before 3-5 years.

Angioplasty↗
PubMed2004

High prevalence of peripheral arterial disease and low treatment rates in elderly primary care patients with diabetes.

Representative data on peripheral arterial disease (PAD) in community-based office practice are scarce while at the same time of high interest. Thus, we aimed to determine the prevalence of peripheral arterial disease (PAD), comorbidity of atherothrombotic manifestations, and treatment intensity among elderly diabetic patients in primary care. In this monitored cross-sectional study, 344 general practitioners throughout Germany determined the ankle-brachial index (ABI) of 6880 consecutive, unselected patients aged 65 years or older with bilateral Doppler ultrasound measurements. PAD was defined according to the recent American Heart Association guidelines (using the higher of the 2 systolic ankle pressures: ABI < 0.9) or peripheral revascularisation, or amputation because of PAD. Coronary events (CAD) and cerebrovascular events (CVD) were taken from the patient's history without additional diagnostic measures. Diabetes was defined according to the clinical diagnosis of the physician and/or HbA1c > or = 6.5 % and/or intake of oral antidiabetic medication and/or application of insulin. 1.743 patients were classified as diabetics: the median disease duration was 6 years (1st; 3rd quartile: 2; 11), median HbA1c 6.6 % (5.9; 7.3), mean age 72.5 +/- 5.4 years, and 51.4 % were females. Diabetics had in comparison with non-diabetics a higher prevalence of PAD defined as ABI < 0.9 (26.3 % vs. 15.3 %, univariate odds ratio 2.0 [95 % confidence interval: 1.7; 2.3]), intermittent claudication (5.1 % vs. 2.1 %, OR: 2.5 [1.9; 3.4]), known CAD (16.1 % vs. 10.6 %, OR: 1.6 [1.4; 1.9]), and known CVD (6.8 % vs. 4.8 %; OR: 1.4 [1.2; 1.8]). 57.4 % of the diabetics with previously known PAD (as only atherothrombotic manifestation) received antiplatelet therapy (vs. 75.1 % with CAD and/or CVD only). The ABI was suitable as screening measure in the primary care setting. In elderly diabetics in comparison to non-diabetics, the prevalence of PAD was very high. Despite the known benefits of antiplatelet therapy, PAD patients were less intensively treated than patients with CAD or CVD.

Aged↗
PubMed2003

[Evaluation of stent-protected angioplasty for theray of symptomatic stenoses of the carotid artery. SPACE and other randomized trials].

During recent years, stent-protected angioplasty of the carotid artery (SPAC) has become an alternative to endartectomy (CEA) in many centers. Despite many case reports, case series, and open records, it has not been proven that these therapeutical regimens are comparable regarding complication rates and long-term outcome. Until now, only three randomized trials were published on this theme, two of them only as abstracts. This is not sufficient for answering the question of whether SPAC is a good alternative to CEA. At present, four major, randomized, multicenter trials are being run (EVA3S in France, CREST in the US, ICSS in Great Britain and several other countries, and SPACE in Germany and Austria). About 7,300 patients will be included in these trials. At present, 24 centers are participating in the SPACE trial, recruiting about 350 patients. It has been prospectively agreed that EVA-3S, ICSS, and SPACE will combine their results after completion of initial randomization and follow-up to conduct a combined European meta-analysis of the data. Three to 5 years are needed until these trials' final results will be published. Until then, stent-protected angioplasty should be done only under the consideration that it has not been scientifically evaluated.

Angioplasty, Balloon↗
PubMed2003

Are elevated homocysteine plasma levels related to peripheral arterial disease? Results from a cross-sectional study of 6880 primary care patients.

BACKGROUND: It is still unclear whether the strength of the association between elevated plasma homocysteine (HC) levels and peripheral arterial disease (PAD), coronary artery disease (CAD) and cerebrovascular disease (CVD) is similar. METHODS: Fasting homocysteine plasma levels were measured in 6880 unselected primary care patients aged 65 years or older. Presence of PAD was determined with the ankle brachial index, and both CAD and CVD were recorded according to patient history. RESULTS: Median homocysteine levels in the total sample (58.0% females, mean age 72.5 years, mean body mass index 27.3 kg m-2) differed between patients with and without PAD: 15.2 micro mol L-1 (95% confidence interval [CI] 14.8; 15.7, vs. 13.9 micro mol L-1 (CI: 13.8; 14.1; P < 0.001). Peripheral arterial disease prevalence moderately increased from 13.0% in the lowest HC quintile to 24.3% in the highest quintile (crude odds ratio [OR], 2.1 [CI: 1.7; 2.6]). The frequency of atherothrombotic manifestations in the patients' history increased nearly linearly across the homocysteine quintiles in the univariate analysis. However, the association diminished substantially after adjusting for known interfering variables: the ORs between the HC highest fifth vs. lowest fifth (adjusted for age, gender, smoking status, diabetes, hypertension lipid disorders, and estimated glomerular filtration rate levels) for PAD decreased to 1.4, for CAD to 1.0 (NS), and for CVD to 1.1. (NS). CONCLUSIONS: Elevated HC is only slightly more related to PAD than to CAD and CVD. After adjustment for known risk factors, the effect size is small, and an association can no longer be observed between homocysteine and CAD and CVD.

Age Distribution↗
PubMed2003

Graft patency and clinical outcome of femorodistal arterial reconstruction in diabetic and non-diabetic patients: results of a multicentre comparative analysis.

OBJECTIVE: in diabetic patients with critical limb ischaemia (CLI) an inferior success rate following infrainguinal bypass surgery is quite often suggested. The aim of this retrospective analysis was, therefore, to evaluate the graft patency and, particularly, the clinical outcome at 1 year in diabetic compared with non-diabetic patients. MATERIAL AND METHODS: two hundred and eleven patients (diabetics 94; non-diabetics 117) with femorodistal reconstruction for CLI were studied. Groups were comparable with regard to the Fontaine classification, the distribution of vascular risk factors, graft material, distal anastomosis site, and the angiographic runoff grading. RESULTS: diabetes did not adversely affect graft function. For diabetics and non-diabetics primary cumulative patency rate at 1 year was found to be 66 and 56%, respectively (p=0.10) and a virtually identical limb salvage rate of 85 and 83% was achieved (p=0.76). With regard to healing of ischaemic foot ulcers a trend against diabetics was noted with a healing rate of 81% compared to 96% in non-diabetics at 1 year (p=0.067); gangrenous foot lesions could be equally remedied in 94% and in 87% among patients with and without diabetes (p=0.44). The survival rate of diabetics, however, was significantly lower with 78% at 1 year compared with 95% in non-diabetic patients (p=0.0004). CONCLUSIONS: our preliminary results support the view that infrainguinal bypass grafting can be safely done even in diabetics. Despite increased mortality in this group, liberal indication for reconstructive vascular surgery seems to be justified by favourable patency rates and clinical outcome in selected patients.

Aged↗
PubMed2002

The Carotid Surgery for Ischemic Stroke trial: a prospective observational study on carotid endarterectomy in the early period after ischemic stroke.

OBJECTIVE: The purpose of this study was to examine the safety of carotid endarterectomy (CEA) within 6 weeks after a nondisabling carotid-related ischemic stroke. Endpoints were the perioperative stroke or mortality rate and the incidence rate of cerebral bleedings. METHODS: This prospective observational multicenter trial was performed in community and university centers. One hundred sixty-four hospitalized patients with nondisabling carotid-related ischemic stroke were included. The patients were identified clinically with the modified Rankin scale (initial neurologic deficit grade >/= 2, n = 160). Four patients with evidence of ischemic territorial infarction on cerebral computed tomographic (CT) scan but no persisting functional deficit were also included. CEA was performed within 6 weeks after stroke. Neurologic examinations were performed initially, before surgery, 3 days after surgery, and 6 weeks after CEA. Worsening of more than 1 grade on the Rankin scale was considered as a new stroke or stroke extension. Unenhanced CT scans of the brain were performed before and after surgery. CT scans were evaluated blind to clinical patient data. Statistical analysis included univariate and multivariate analysis. RESULTS: The combined stroke or mortality rate within 30 days after CEA was 6.7%. Ten patients had a new ipsilateral stroke or stroke extension, and one patient died after surgery of a myocardial infarction. One patient (0.6%) had parenchymatous cerebral bleeding, and in 10 patients, hemorrhagic transformation within the preexisting ischemic infarction was detected but no infarct extension was observed. In the multivariate analysis, American Society of Anesthesiology (ASA) grades III and IV and decreasing age were significant predictors for an increased perioperative risk. Patients with a higher risk profile (ASA classification grades III and IV) had a high perioperative risk when CEA was performed within the first 3 weeks (14.6% versus 4.8% beyond 3 weeks). Patients without severe concomitant diseases (ASA grades I/II) had a low perioperative risk of 3.4% if CEA was performed within the first 3 weeks. CONCLUSION: Early CEA within 6 weeks after a carotid-related ischemic stroke can be performed with a perioperative stroke or mortality rate comparable with the results reported in the European Carotid Surgery Trial and the North American Symptomatic Carotid Endarterectomy Trial. The risk of parenchymatous bleeding is low. ASA grades III and IV and decreasing age were predictive of an increased perioperative risk, especially if CEA was performed within the first 3 weeks. Patients at low risk can undergo operation safely within the first 3 weeks. Individual patient selection in an interdisciplinary approach between neurologists, anesthesiologists, and vascular surgeons remains mandatory in these patients.

Aged↗
PubMed2001

[Aortic dissection--when operative treatment, when endoluminal therapy?].

GOAL: To demonstrate the Heidelberg results of the previous 2 years in patients referred for acute aortic dissection. MATERIAL AND METHODS: 93 patients referred for acute aortic dissection were treated by cardiac surgery, vascular surgery and interventional radiology according to a novel therapeutic algorithm including stent-grafts and combined open and interventional procedures and conservative medical therapy when no malperfusion syndrome was present or patients were considered prohibitive for even minor surgical procedures. Stent-graft placements were done assisted by short term cardiac arrest to facilitate correct device deployment. RESULTS: 36 patients presented with type A and the other 57 with type B dissection. 32 of the A patients were operated and 20 of the B patients, respectively. 12 patients with B dissection were treated with stent-grafts. 3 required additional interventional therapy for organ malperfusion. The mortality was 0% in these 12 patients The overall mortality rate in the A group was close to 40% mainly as a result of postoperative organ malperfusion while it was 15% in the B group. In both groups mortality was highest in the respective untreated patient subgroup (3/4 and 8/37, respectively). The main mortality factor was visceral (mesenteric or liver) ischemia. Paraplegic complications occured in neither group. In 4 patients a combined approach applying cardiac surgery of the ascending aorta and endluminal stent-graft placement for the residual B dissection was successfully performed. In one patient this was done simultaneously. DISCUSSION: Acute aortic dissection of type A with or without valve involvement, coronary artery ischemia can be treated with high technical success rates. However, remaining distal aortic dissection associated with true lumen collapse and organ malperfusion is the main causative factor for clinical failures. Successful combination of open proximal aortic surgery with endoluminal treatment of residual B dissection encourages further use of this novel approach. Acute B type dissection appears to be effectively and safely treated by endoluminal approach in selected cases. Unsolved questions of this less invasive therapeutic approach focus mainly on the design of the proximal anchoring part of the devices.

Acute Disease↗
PubMed2001

[Post-traumatic dissection of the abdominal aorta].

Dissections due to deceleration trauma are rarely limited to the infradiaphragmal aorta (only 2-3%) and are usually lethal. Here we report the unusual course of an abdominal aortic dissection with aneurysmatic enlargement of the false lumen. Based on diagnostic imaging, a therapeutic stent application was planned in order to close the entry and to prevent rupture. During the intervention sondation of the false lumen revealed that the left renal artery had a reentry. Due to the complexity of the entry-reentry situation of the left renal artery the intervention was not possible, and the patient had to undergo vascular surgery.

Abdominal Injuries↗
PubMed2001

Characterization of renal parenchymal perfusion during experimental infrarenal aortic clamping and declamping with enhanced thermodiffusion electrodes.

Despite multiple previous experimental and clinical investigations, it has not been fully clarified until now whether infrarenal aortic cross-clamping (IRAC) induces a significant disturbance of renal parenchymal perfusion. Most renal cortical flow data collected thus far have been heterogenous because of inherent limitations of available measurement technology. The enhanced thermal diffusion (TD) electrode is a newly developed and previously validated prototype device that allows continuous quantification of parenchymal kidney perfusion after local probe implantation. We monitored renal perfusion during experimental IRAC with TD for the first time, thereby also evaluating the potential applicability of the method in clinical aortic surgery. IRAC (20 min) followed by sudden declamping was performed in pigs under general anesthesia (n = 14). Renal cortical blood flow (RCBF) was continuously quantified by TD, total aortic flow (TABF) and renal artery flow (RABF) were measured by ultrasonic flow probes, and parameters of systemic circulation were determined by Swan-Ganz catheter. Our results showed that kidney perfusion can be continuously quantified using TD electrodes during experimental aortic surgery in a porcine model. IRAC does not lead to a significant impairment of RCBF in young pigs as measured by TD. Renal perfusion appears to be predominantly pressure driven. Consequently, abrubt aortic declamping can bring about prolonged renal ischemia. Transfer of the TD method to RCBF monitoring during clinical aortic surgery appears to be feasible and should be investigated in selected cases.

Animals↗
PubMed2001

Grading of internal carotid artery stenosis: validation of Doppler/duplex ultrasound criteria and angiography against endarterectomy specimen.

OBJECTIVES: duplex ultrasound has replaced angiography prior to carotid endarterectomy (CEA) in many institutions. However, the indications for CEA are based on angiographically controlled studies and widely accepted ultrasound criteria do not exist. Consequently, the reliability of Doppler and/or duplex ultrasound to predict a high-grade ICA stenosis has to be proven. DESIGN: prospective validation study. MATERIALS: one hundred and fifty carotid bifurcations assessed by ultrasound and selective angiography and 68 acrylat outcasts of carotid specimen after eversion CEA. METHODS: ICA stenosis was measured angiographically according to the ECST criteria. Combined Doppler acoustic standard criteria (CDASC), peak systolic frequency (PSF), peak systolic velocity (PSV) and end-diastolic velocity (EDV) served as criteria for the ultrasound assessment. These criteria and the results of angiography were compared to the degree of ICA stenosis determined by specimen measurements. RESULTS: the median degree of ICA stenosis as assessed by angiography (82%, range 56-97%) and CDASC (83%, range 50-99%) corresponded well to the specimen measurements (80%, range 50-95%). The sensitivity of angiography and CDASC to predict a 70-90% ICA stenosis (ECST criteria) compared to the specimen measurements was 88% and 95%, respectively. The positive predictive value (PPV) reached 92% and 96%, respectively. CDASC were equivalent to angiography and were superior to the best single frequency or velocity parameters. If CDASC do not indicate a >/=70% ICA stenosis in spite of a PSV >/=180 cm/s and/or an EDV >/=50 cm/s, angiography may detect patients with a >70% ICA stenosis. CONCLUSIONS: CDASC are valid in the quantification of high-grade ICA stenosis. They are more reliable than single velocity and/or frequency measurements. However, if velocity criteria and CDASC do not agree, angiography should be performed.

Angiography↗
PubMed2001

Immunophenotypic characterisation of carotid plaque: increased amount of inflammatory cells as an independent predictor for ischaemic symptoms.

OBJECTIVES: To investigate the inflammatory response within intact carotid plaques from carotid eversion endarterectomy (CEE) to determine the relationship between immunohistological plaque morphology and ischaemic cerebrovascular symptoms. MATERIAL AND METHODS: Intact CEE plaques from 71 patients with high-grade (>70%) stenosis undergoing CEE (group I, symptomatic, n=42; group II, asymptomatic, n =29) and 12 normal postmortem arteries (control group) were analysed with specific antibodies to inflammatory cells (T-Lymphocytes (CD3, CD4), cytotoxic T-cells (CD8), B-lymphocytes (CD20), natural killer cells (CD57), macrophages (CD68)), endothelial adhesion molecules (ICAM-1 (CD54), P-selectin (CD62P), E-selectin (CD62E), VCAM-1 (CD106) and T-lymphocyte co-stimulatory molecule (CD40)) and procoagulatory modulators (thrombomodulin (CD141), tissue factor (CD142)). Both groups were matched for gender, age, risk factors, degree of carotid artery stenosis. Plaques were measured using a semiquantitative score system in a blinded fashion by two observers. Statistical analysis of the group differences were performed by using the Kruskal-Wallis test and the Multitest Procedure with Permutation-Testing. Significance was taken as a p<0.05. RESULTS: There were significantly more inflammatory cells, an overexpression of P-selectin and the procoagulatory markers thrombomodulin and tissue factor in symptomatic compared to both asymptomatic plaques and the ones of the control group. In both groups there was no significance for ICAM-1, VCAM-1, macrophages and co-stimulatory molecule CD40. There was also no significance for any factor between the asymptomatic and the control group. However, the differences between the symptomatic and the asymptomatic group were highly significant for all factors. CONCLUSION: These data suggest that structural changes and inflammatory damage within the individual plaque seems to be a critical step in promoting plaque rupture with embolic sequelae.

Adult↗
PubMed2001

Dacron vs. polytetrafluoroethylene grafts for femoropopliteal bypass: a prospective randomised multicentre trial.

OBJECTIVES: To compare the patency of PTFE (Polytetrafluoroethylene) and unsealed knitted Dacron femoro-popliteal bypasses. DESIGN: Multi-centre prospective randomised trial. MATERIALS AND METHODS: Of 203 patients randomised, 194 were included in the final analysis (103 Dacron grafts and 91 PTFE grafts). The median follow-up was 36 months (range: 6-72 months); the distal anastomosis was above-knee in 141 and below-knee in 53 cases. Univariate comparisons of patency were made by the Kaplan-Meier method, multivariate calculations on the effects of covariables by a Cox regression analysis. RESULTS: There was no difference regarding primary and secondary patency or limb salvage between Dacron and PTFE. The primary 3-year patency for Dacron grafts was 64% (95% confidence interval [C.I.] 55-74%) and for PTFE grafts 61% (C.I. 49-72%). The corresponding 3-year secondary patency was 81% (C.I. 73-89%) and 75% (C.I. 65-86%) respectively, the limb salvage rate 90% (C.I. 84-96%) and 91% (C.I. 84-97%). Upon multivariate analysis below-knee anastomosis was the principal independent predictor of primary graft failure (risk ratio 1.7 [C.I. 1.05-2.8]), impaired secondary patency was associated with infragenicular bypass (risk ratio 3.3 [C.I. 1.8-6.3]) and distal gangrene (risk ratio [C.I. 1.01-3.8]p=0.048), major amputation was independently predicted by below-knee bypass, tissue necrosis, and poor run-off index. CONCLUSIONS: PTFE and Dacron are equally suitable for femoro-popliteal bypass.

Adult↗
PubMed2001

Carbon dioxide angiography for endovascular grafting in high-risk patients with infrarenal abdominal aortic aneurysms.

Allergic reactions to contrast media, preexisting renal dysfunction, and hyperthyroidism are relative contraindications for angiography with conventional contrast medium. Carbon dioxide (CO(2)) angiography is an alternative method in high-risk patients because CO(2) is nontoxic, without allergic potential, and not iodic. CO(2)-related complications are extremely rare. Because renal insufficiency often occurs in vascular patients, this method will become increasingly important for endovascular surgery. We report on three consecutive patients with asymptomatic infrarenal aortic aneurysm and concomitant renal dysfunction or allergic reactions to standard contrast media. Aortic stent grafts were deployed under CO(2) angiographic control without complications or worsening of renal function.

Aged↗