[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.

[Rational radiologic after-care of endoluminal aortic bypass]

GOAL

To identify essential and relevant diagnostic algorithms in the follow-up of stent-grafts placed for aortic dissections and aneurysms based on our 7 years experience including the use of more than 10 different devices.

MATERIAL AND METHODS

Evaluation of conventional biplane imaging, angiography, sonography, CT and MR in the efficacy of demonstrating endoleaks, sac shrinkage, changes of stent-graft integrity and, with special reference to MR-compatibility of various stent-graft devices.

RESULTS

Endoleaks are found in 20-30% of patients after endovascular exclusion of abdominal aortic aneurysms. However, this rate neither necessarily reflects the clinical course nor the onset and course of sac shrinkage. Physical long-term integrity of the devices is seen best on conventional bi-plane radiographs. Sonography is helpful only in selected patients (non-obese, good compliance) otherwise not providing information precisely enough for sac control. As gold standard both CT (CTA) and MR (MRA) are equally effective in the follow-up of endovascular stent-grafts, allowing 3D control of sac geometry in aneurysmal disease or hemodynamic changes in stent-grafts for aortic dissection. MRI is considered to be more effective in the detection of small endoleaks. Angiography is inferior to CT and MRI in the diagnosis of endoleaks and thus is required only for intervention planning in patients with suspected endoleaks. Two of 8 evaluated stent-graft devices proved to be prohibitive for MRI because of their severe artifacts productions (Life-path, Zenith) as a result of their thick metallic meshwork.

CONCLUSION

CT including CTA with 2D and 3D reformatting is the method of choice for the follow up of stent-graft treatment of aortic disease. Depending on availability, MRI may be used alternatively. In young patients and for those with contraindications to iodinated contrast media MRI is a perfectly equivalent alternative. Especially in patients with known contraindications to iodinated contrast media the MR-compatibility should be taken into consideration in the choice of the endovascular device.

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.

Assessment by flow cytometry of peripheral blood leukocyte enzymatic activities in HIV patients

Leukocyte enzymatic activities are important in non-specific protection against bacterial infections, but traditional methods for the detection of intracellular enzymatic activities rely on cumbersome and complex assays. The development of specific substrates, which become fluorescent upon degradation of the biomolecule after its passive entry into intact cells, permits a simplified evaluation of leukocyte enzymatic activities. We have used this method to assess intracellular elastase, collagenase and cathepsin D activities of peripheral blood leukocytes using flow cytometry in a series of HIV patients and healthy controls. Monocytes displayed the highest enzymatic activities for the three proteases tested. In HIV-infected patients, the collagenase and cathepsin D activities of monocytes were significantly lower, whereas the elastase and cathepsin D activities of polymorphonuclear cells were elevated. Slightly higher elastase activity was detected in the lymphocytes of patients. This study demonstrates the feasibility of this new method for the study of intracytoplasmic enzymatic activities. Significant variations were observed in the peripheral blood of HIV-infected patients and different patterns were especially evident in monocytes and polymorphonuclear cells.

[Recurrence of cystic adventitial degeneration of the popliteal artery--magnetic resonance tomography and MR angiography]

Adventitial cystic disease is a rare disorder characterized by mucin-containing cysts of the adventitial tissue. The condition has a predilection for the popliteal artery. Men are predominantly affected, usually around the fourth decade. We report of a case of recurrent adventitial cystic disease and the possibilities of modern cross-sectional imaging. In particular we discuss the advantages of magnetic resonance imaging and magnetic resonance angiography for the diagnosis of this condition. Furthermore, the etiology and the possibilities of surgical treatment are illustrated.

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.

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.

Does the time of administration (morning or evening) affect the tolerability or efficacy of tamsulosin?

OBJECTIVE

To determine whether the time of dosing (morning or evening) affects the tolerability or efficacy of tamsulosin in the treatment of lower urinary tract symptoms.

PATIENTS AND METHODS

Data were analysed from an open-label, observational study in which patients were treated with 0.4 mg tamsulosin once daily for 12 weeks. Treatment effects were determined using the Benign Prostatic Hyperplasia Impact Index, the quality-of-life question of the International Prostate Symptom Score, a similarly phrased question about sexual satisfaction, the maximum urinary flow rate, the postvoid residual urine volume, and the overall efficacy and tolerability. The results were analysed statistically for differences between dosing times, using analysis of covariance for the quantitative variables and logistic regression for the qualitative variables.

RESULTS

While no specific recommendation about the dosing time was given in the trial, the retrospective analysis showed that 4420 and 2087 patients received tamsulosin in the morning and evening, respectively. Both groups had similar values for all variables before treatment. The efficacy and tolerability of tamsulosin treatment was also similar in both groups; there were small advantages for morning dosing, which were statistically significant because there were many patients.

CONCLUSION

In contrast to other alpha-blockers, night-time dosing is not necessary to improve the tolerability or efficacy of tamsulosin.

Clinical, endocrine, and molecular genetic findings in patients with 17beta-hydroxysteroid dehydrogenase deficiency

Mutations in the 17beta-hydroxysteroid dehydrogenase (17beta-HSD) type 3 gene are associated with the clinical findings of 17beta-HSD deficiency. We investigated 5 patients of German descent with 46,XY karyotype and predominantly female phenotype. Androstenedione (A) and testosterone (T) levels in serum were determined before and after stimulation with human chorionic gonadotropin. DNA analysis of the whole coding region of the 17beta-HSD type 3 gene was performed by PCR, single-strand conformation analysis, and direct sequencing. In all patients we found highly variable A and T levels before and after stimulation. However, the A-to-T ratio was abnormal in all cases suggestive of 17beta-HSD deficiency. Molecular genetic analysis revealed mutations in all patients. We conclude that A and T levels may be highly variable in patients with 17beta-HSD deficiency. Molecular genetic analysis of the 17beta-HSD gene may support the diagnosis of this disorder.

Isolation of Kingella kingae from synovial fluids using four commercial blood culture bottles

According to the literature, Kingella kingae may be an underdiagnosed cause of joint and bone infections in children. The use of the Bactec blood culture system for culture of joint fluids has dramatically improved the isolation of this fastidious bacterium. The aim of this study was to test the recovery rate and detection time of four commercial blood culture systems: three different BacT/Alert (Organon Teknika, USA) bottles and one Bactec (Becton Dickinson Microbiology Systems, USA) bottle, all inoculated with Kingella kingae strains mixed with pooled synovial fluids. For each strain the same inoculum and volume of synovial fluid was distributed into each of the four bottles. All 24 strains tested grew in the BacT/Alert Aerobic (100%) and the BacT/Alert Pedi-BacT (100%) bottles. Twenty-one strains grew in the BacT/Alert FAN aerobic (88%) bottle, and 15 strains grew in the Bactec Plus Aerobic F (63%) bottle, in both systems within 12 days (P<0.01). The Kingella kingae strains were first detected in the BacT/Alert Pedi-BacT bottles (P<0.001). The results were reproducible. The BacT/Alert blood culture bottles were superior to previously described blood culture systems in isolating Kingella kingae from synovial fluid, even with small inoculums and small volumes of synovial fluid.

Cross-resistance patterns among clinical isolates of Klebsiella pneumoniae with decreased susceptibility to cefuroxime

The frequency of decreased susceptibility to cefuroxime and quinolones and the correlation between these drug resistance traits was investigated in clinical isolates of Klebsiella pneumoniae from two Danish counties. Eighty-three randomly selected clinical isolates of K. pneumoniae with decreased susceptibility to cefuroxime were examined for cross-resistance patterns and the production of beta-lactamases. The frequency of resistance to cefuroxime and ciprofloxacin has increased from <5% in 1990 to 15% and 7% in 1998, respectively. Two of the 83 isolates were multiply resistant and seemed to produce extended-spectrum beta-lactamases. However, cross-resistance to ciprofloxacin and other classes of drug in 68% of the remaining isolates indicates that other resistance mechanisms, such as penetration barriers, had probably been selected in these Danish isolates. The susceptibility to ciprofloxacin decreased successively with decreasing susceptibility to cefuroxime for K. pneumoniae. This did not occur in cefuroxime-resistant Escherichia coli.

Effect of diabetes on lower urinary tract symptoms in patients with benign prostatic hyperplasia

PURPOSE

Several studies have suggested a specific association between the presence and/or symptom intensity of benign prostatic hyperplasia (BPH) and diabetes but to our knowledge no definitive conclusion has been reached. Therefore, we examined the intensity of lower urinary tract symptoms in a large cohort of men with BPH with and without diabetes. We then determined whether the alpha1-adrenoceptor antagonist tamsulosin similarly improved lower urinary tract symptoms in patients with BPH with or without diabetes.

MATERIALS AND METHODS

The International Prostate Symptom Score (I-PSS), maximum flow rate and post-void residual were determined in 9,856 men with clinically diagnosed BPH, of whom 1,290 also had diabetes, at baseline and after a 12 week, open label course of 0.4 mg. tamsulosin daily.

RESULTS

Logistic regression of the baseline data indicated that older age and I-PSS were independently associated with a statistically significant increase in the odds ratio of having diabetes. Accordingly, diabetics had a significantly greater baseline I-PSS and smaller maximum flow rate than non-diabetic patients on age-adjusted analysis, while residual urine was not significantly altered. Tamsulosin markedly improved lower urinary tract symptoms. The extent of improvement was similar in diabetic and nondiabetic patients, although some slight differences reached statistical significance due to large patient numbers.

CONCLUSIONS

The severity of lower urinary tract symptoms in patients with BPH and the likelihood of having diabetes are significantly associated. Within the limitations of an open label, observational study tamsulosin appears to reduce lower urinary tract symptoms similarly in patients with BPH with or without diabetes.

[Urgent and emergency carotid TEA]

Restoration of blood flow to reperfuse ischemic but not infarcted areas of the brain (ischemic penumbra) and the removal of an ongoing embolic source are the therapeutic aims of emergency and urgent carotid endarterectomy (CEA), both in patients with an acute or progressive ischemic stroke and in patients in the early period after a carotid-related stroke. Based on poor results in the 60ies and 70ies, many centers traditionally perform CEA four to six weeks after a carotid-related stroke at the earliest interval. Since natural history is associated with a high risk of an disabling and/or recurrent stroke in several subgroups of patients, some reports were able to show that urgent and emergency CEA could be worthwhile in well-selected patients.

Clustering of mutations associated with mild Marfan-like phenotypes in the 3' region of FBN1 suggests a potential genotype-phenotype correlation

Mutations in the gene for fibrillin-1 (FBN1) cause Marfan syndrome, a dominantly inherited disorder of connective tissue that primarily involves the cardiovascular, ocular, and skeletal systems. There is a remarkable degree of variability both within and between families with Marfan syndrome, and FBN1 mutations have also been found in a range of other related connective tissue disorders collectively termed type-1 fibrillinopathies. FBN1 mutations have been found in almost all of the 65 exons of the FBN1 gene and for the most part have been unique to one affected patient or family. Aside from the "hot spots" for the neonatal Marfan syndrome in exons 24-27 and 31-32, genotype-phenotype correlations have been slow to emerge. Here we present the results of temperature-gradient gel electrophoresis analysis of FBN1 exons 59-65. Six mutations were identified, only one of which had been previously reported. Two of the six mutations were found in patients with mild phenotypes. Taken together with other published reports, our results suggest that a sizable subset (ca. 40%) of mutations in this region is associated with mild phenotypes characterized by the lack of significant aortic pathology, compared with about 7% in the rest of the gene. In two cases, mutations affecting analogous positions within one of the 43 cbEGF modules of FBN1 are associated with mild phenotypes when found in one of the 6 C-terminal modules (encoded by exons 59-63), but are associated with classic or severe phenotypes when found in cbEGF modules elsewhere in the gene.

Emergency carotid endarterectomy

OBJECTIVE

Evaluation of the therapeutical efficacy of emergency carotid endarterectomy (CEA) in neurologically unstable patients.

PATIENTS AND METHODS

Three groups of a consecutive series of 71 emergency CEAs performed from 1980 to July 1998 were classified: (1) acute onset of severe stroke (n = 16), (2) progressive stroke/stroke in evolution (n = 34), and (3) crescendo transient ischemic attacks (n = 21). Cerebral coma, cerebral haemorrhage, and major ischemic stroke established in cranial computed tomography scans were contraindications for surgery. The neurological outcome was assessed by the modified Rankin scale. Long-term survival and long-term stroke recurrences were analyzed.

RESULTS

The recovery/minor stroke rates (Rankin 0-3) in acute stroke, progressive stroke, and crescendo transient ischemic attacks were 56.3, 76.4 and 80.9%, respectively; the combined major stroke/mortality rates (Rankin 4-6) were 43.7, 23.6 and 19.1%, respectively. Intraoperative angiography in 39 patients detected early carotid reocclusions in 2 and intracranial embolism in 7 patients. Local application of thrombolytic agents (n = 5) may contribute to a better neurological outcome in emergency CEA. Life table probabilities of major strokefree survival were 74.5, 71.6, and 53.7% after 1, 2, and 5 years, respectively (including perioperative strokes). Life table probabilities to suffer no stroke recurrence during follow-up were 96.7, 96.7 and 85.3%, respectively (perioperative strokes excluded).

CONCLUSIONS

Emergency CEA may be worthwhile in selected patients. Completion angiography is mandatory. Emergency CEA should be included in therapeutic strategies for ischemic stroke.

[Endovascular prostheses: evolution, state-of-the-art and perspectives of a new technology]

The treatment of infrarenal aortic aneurysms by means of transluminally placed endovascular prostheses reflects significant progress in the field of vascular surgery. In the case of infrarenal aortic aneurysm it is possible to achieve technically successful implantation of such a prosthesis in well over 90 % of cases. The rate of clinical success, meaning lasting effective exclusion of the aortic aneurysm, cannot (yet) be definitively determined, since no long-term results are so far available. Secondary leaks are observed in at least 10 % of all patients, making a further therapy necessary (endorepair, conversion, embolization). Further development of endovascular prostheses will include optimization of the aortal/iliac attachment of the prostheses, a better configuration and the development of long-lasting materials that can be used for endovascular prostheses.

[Adenosine-induced heart arrest for endovascular reconstruction of thoracic aneurysms of the aorta]

INTRODUCTION

Endovascular stent-graft repair is a less invasive technique than traditional open aortic reconstruction for strictly selected patients with descending thoracic aortic aneurysms. To prevent distal migration of the device as a result of the propulsive flow during systole, it is helpful to induce temporary asystole for > or = 20 s while the stent-graft is placed in the thoracic aorta.

CASE STUDY

We report here a case study of a patient who was given a bolus dose of 60 mg of adenosine to induce temporary asystole. Placement of the stent-graft was successfully performed during the temporary asystole. After 45 s the patient returned to normal sinus rhythm. He was extubated 4 h after the conclusion of surgery and was discharged after 1 week.

CONCLUSION

Induction of temporary asystole with bolus adenosine to facilitate placement of stent-grafts in the thoracic aorta is a simple, easy and effective method of avoiding distal device migration.

Carotid endarterectomy and intracranial thrombolysis: simultaneous and staged procedures in ischemic stroke

PURPOSE

The feasibility and safety of combining carotid surgery and thrombolysis for occlusions of the internal carotid artery (ICA) and the middle cerebral artery (MCA), either as a simultaneous or as a staged procedure in acute ischemic strokes, was studied.

METHODS

A nonrandomized clinical pilot study, which included patients who had severe hemispheric carotid-related ischemic strokes and acute occlusions of the MCA, was performed between January 1994 and January 1998. Exclusion criteria were cerebral coma and major infarction established by means of cerebral computed tomography scan. Clinical outcome was assessed with the modified Rankin scale.

RESULTS

Carotid reconstruction and thrombolysis was performed in 14 of 845 patients (1.7%). The ICA was occluded in 11 patients; occlusions of the MCA (mainstem/major branches/distal branch) or the anterior cerebral artery (ACA) were found in 14 patients. In three of the 14 patients, thrombolysis was performed first, followed by carotid enarterectomy (CEA) after clinical improvement (6 to 21 days). In 11 of 14 patients, 0.15 to 1 mIU urokinase was administered intraoperatively, ie, emergency CEA for acute ischemic stroke (n = 5) or surgical reexploration after elective CEA complicated by perioperative intracerebral embolism (n = 6). Thirteen of 14 intracranial embolic occlusions and 10 of 11 ICA occlusions were recanalized successfully (confirmed with angiography or transcranial Doppler studies). Four patients recovered completely (Rankin 0), six patients sustained a minor stroke (Rankin 2/3), two patients had a major stroke (Rankin 4/5), and two patients died. In one patient, hemorrhagic transformation of an ischemic infarction was detectable postoperatively.

CONCLUSION

Combining carotid surgery with thrombolysis (simultaneous or staged procedure) offers a new therapeutic approach in the emergency management of an acute carotid-related stroke. Its efficacy should be evaluated in interdisciplinary studies.

[Computer-assisted evaluation of aortic aneurysm morphology for choosing the method of therapy]

Computer aided surgery planning software for AAA is a industry-standard software development for viewing patient-specific data on a personal computer through a unique approach, which improve visualization, navigation, and decision support capabilities for both open and endovascular surgery. Raw scan data is extracted from CT scans, and rendered into a three-dimensional format. This 3D modeling technology and user interface provides a patient-specific model with a rapid visual access to the full range of information, including accurate 3D assessment of AAA morphology and pathology, interactive multiplanar reconstructions, measurements, and views to assist the surgeon in understanding of complex 3D relationships. It provides an optimal system for patient evaluation and selection for endovascular repair of AAA and in the post-operative evaluation of stent deployment and/or complications, such as endoleaks.

[Computer-based training exemplified by the carotid artery]

The purpose of computer-based training (CBT) is interactive use of multimedia components, such as text, graphics, animation, sound, digital slide shows, and videos. This CD-ROM illuminates different aspects of carotid surgery: cerebrovascular insufficiency, sonographic and neuroradiological diagnostics, indications and results of carotid surgery in the literature, perioperative complications and new developments such as interventional procedures. Digital imaging (60 minutes of video sequences and 250 graphics) especially focus on operative standard procedures (conventional and eversion technique) and alternative methods. CBT is an evolving supplement to improve education programs in vascular surgery.

[Indications for urgent carotid reconstruction]

Diagnostic methods and indications for carotid surgery must be coordinated with the individual carotid-related stroke risk. The indication for urgent carotid reconstruction within a few days after the initial event should always be evaluated when a clinical and/or morphological unstable and therefore risky carotid lesion is present and the 30-day stroke risk without surgery is > 5%. Patients with high-grade symptomatic carotid stenoses fulfill these criteria as do patients with recurrent carotid-related TIA, patients with hemipheric TIA, patients with symptomatic carotid stenosis and contralateral carotid occlusion and patients after a non-disabling carotid-related stroke. The clinical significance of sonographic carotid plaque criteria and intracranial emboli detected by TCD must be further evaluated in prospective studies.

[Endovascular infrarenal surgery of abdominal aortic aneurysm in selected patients: 3-years outcome and complication management]

We report a over 3-year single center experience with five different self-expanding or ballon-expandable stent-graft devices used for aneurysm exclusion in the infrarental aorta. All devices appeared to offer a safe, efficacious, and minimally invasive means of excluding the aneurysms from circulation. Key to success is restrictive patient selection due to morphological criteria and improvements in surgical techniques and equipment to reduce the incidence of complications and endoleaks. At the moment, patients who opt for the endovascular method of repair should be aware that the minimally invasive technique carries the disadvantage of a higher failure rate compared to open surgery. Long-term results are required to establish selection criteria, especially for younger patients.

Differential vascular alpha1-adrenoceptor antagonism by tamsulosin and terazosin

AIMS

In patients with lower urinary tract symptoms suggestive of benign prostatic obstruction the alpha1-adrenoceptor antagonist terazosin lowers blood pressure whereas only very small if any alterations were reported with the alpha1-adrenoceptor antagonist tamsulosin. Therefore, we have compared the vascular alpha1-adrenoceptor antagonism of tamsulosin and terazosin directly.

METHODS

Ten healthy subjects were investigated in a randomized, single-blind, three-way cross-over design and received a single dose of 0.4 mg tamsulosin, 5 mg terazosin or placebo on 3 study days at least 1 week apart. Before and 1, 3, 5, 7, 10 and 23.5 h after drug intake, alterations of diastolic blood pressure and other haemodynamic parameters in response to a graded infusion of the alpha1-adrenoceptor agonist phenylephrine were determined non-invasively.

RESULTS

At most time points tamsulosin inhibited phenylephrine-induced diastolic blood pressure elevations significantly less than terazosin (5 h time point: median difference in inhibition 35%, 95% CI: 18.7-50.3%). On the other hand, phenylephrine-induced changes of cardiac output, heart rate and stroke volume were similar during both active treatments.

CONCLUSIONS

In doses equi-effective for treatment of lower urinary tract symptoms tamsulosin causes less inhibition of vasoconstriction than terazosin.

Detection of extended-spectrum beta-lactamases. The reliability of methods for susceptibility testing as used in Denmark

The susceptibility testing methods used in Denmark were evaluated with respect to their ability to detect cephalosporin resistance with cefuroxime as indicator, especially resistance caused by extended-spectrum beta-lactamases (ESBLs). Two methods for determination of minimal inhibitory concentration (MIC), three agar diffusion methods, a disc approximation test and the ESBL-Etest were used against a panel of strains producing well-known beta-lactamases. The tablet diffusion test (Rosco Neo Sensitabs) as the most used in Denmark had the lowest detection rate of cefuroxime resistance among ESBL-producing strains. The prediffusion method, which is only used at one laboratory, was the most reliable method for such detection. The MIC methods were in good agreement, but the detection rate for resistance due to ESBLs was low and depended on the antibiotics used. The disc approximation test and the ESBL-Etest both resulted in an acceptable ESBL detection rate. The latter tests discriminated between isolates producing the frequent chromosome-mediated and the in Denmark probably very rare ESBL-mediated cephalosporin resistance. For the evaluation of susceptibility tests such strains require special attention.