[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.

Concentration changes of malondialdehyde across the cerebral vascular bed and shedding of L-selectin during carotid endarterectomy

BACKGROUND AND PURPOSE

Oxidative stress has been postulated to account for delayed neuronal death due to ischemia/reperfusion. We investigated cerebral formation of malondialdehyde as an index of lipid peroxidation in relation to different sources of reactive oxygen species in patients undergoing carotid endarterectomy.

METHODS

In 25 patients undergoing carotid endarterectomy, jugular venous-arterial concentration differences of brain metabolites, malondialdehyde, plasma total antioxidant status, and soluble P-selectin and L-selectin were measured. A carotid artery shunt (n=5) was placed only after complete loss of somatosensory evoked potentials, indicating a focal cerebral blood flow <15 mL/min per 100 g.

RESULTS

As an indication of cerebral lipid peroxidation, jugular venous-arterial malondialdehyde concentration differences were significantly enhanced before reperfusion, and an additional rise was observed 15 minutes after reperfusion. Plasma total antioxidant status significantly decreased during carotid artery occlusion only in patients with carotid artery shunt. This decrease was matched by cerebral formation of adenosine, hypoxanthine, and nitrite/nitrate. While jugular venous-arterial concentration differences of soluble P-selectin showed changes similar to those of malondialdehyde, the concentration difference for soluble L-selectin was enhanced exclusively at 15 minutes after reperfusion.

CONCLUSIONS

Short-term incomplete cerebral ischemia/reperfusion significantly enhanced cerebral lipid peroxidation, as indicated by malondialdehyde formation. The generation of reactive oxygen species by xanthine oxidase or nitric oxide metabolism might be involved in the induction of lipid peroxidation. The additional rise in cerebral release of malondialdehyde was found to coincide with a significant activation of polymorphonuclear leukocytes across the cerebral circulation.

[Carotid endarterectomy in the early phase after a non-disabling stroke: 1980-1995 results]

In 56 patients, carotid endarterectomy (CEA) was performed 14 days (median) after a non-disabling carotid-related stroke with a perioperative minor stroke rate of 3.6%. Even large ischemic brain infarcts on CT scan did not exclude patients from CEA, as long as the patient had reached a neurologic plateau. The data from this study indicate that CEA can be performed safely in properly selected patients, and might reduce the high risk of a recurrent stroke (5%-9.5% within 30 days).

Early carotid endarterectomy after non-disabling ischaemic stroke: adequate therapeutical option in selected patients

OBJECTIVE

To evaluate neurological outcome and long-term results of early carotid endarterectomy (CEA) after non-disabling stroke.

MATERIALS

Retrospective study between 1980 and 1995 of 56 patients undergoing CEA within 4 weeks of a transient (n = 15) or a permanent non-disabling (n = 41) ischaemic stroke.

METHODS

Analyses of preoperative cerebral CT imaging, neurological outcome (mod. Rankin-scale) and long-term results (life-table analyses according to Kaplan-Meier).

RESULTS

Incidence of early CEA increased from 1.7% (27 out of 1636) in the period 1980-1993 to 7.8% (29 out of 374) between 1994 and 1995. CEA was indicated after a neurological plateau phase was established (median interval 14 days). Fifty-seven per cent of the CEA patients had a minor ischaemic infarction (area < 2 cm), 18% showed a large territorial ischaemic infarction (area 2-5 cm) in cerebral CT imaging. Two patients deteriorated postoperatively (minor stroke rate 4%) but no major stroke or death occurred. Life-table probability of stroke-free survival (mean follow-up 42.7 months) was 94%, 90% and 84%, respectively, after 1, 2 and 5 years. Kaplan-Meier survival rates were 96%, 91% and 86% after 1, 2 and 5 years.

CONCLUSIONS

Early CEA after non-disabling stroke is a safe procedure in selected patients.

Stroke from internal carotid artery occlusion during mumps infection

During the terminal incubation period of severe mumps infection, a 40-year-old patient suffered from large infarction in the right middle cerebral artery territory. The proximal right internal carotid artery (ICA) was occluded on angiography. Computed tomography of the neck detected a hemorrhage located ventromedial to the right common carotid artery. Four months later the right ICA was partly recanalized. Carotid surgery revealed an atherosclerotic plaque and a vessel wall, which was fragile and less compact than usually. A strong inflammatory reaction to mumps infection may have contributed to the pathogenesis of the cervical hemorrhage and to acute thrombosis and occlusion of the ICA.

[Bilateral tibial compartment syndrome with crush symptoms after cannabis abuse]

Acute compartmental syndrome (CS) is a surgical emergency. Different conditions in which high non-physiological pressure appears within a closed fascial space reduce the necessary blood perfusion. CS is caused by trauma, burns, bleeding in patients with coagulopathies arterial injuries, nephrotic syndrome or unusual physical exercise with secondary compartmental swelling. When decompression occurs too late, permanent loss of function and limb contracture may result. In the following paper we report on a case of four-compartmental syndrome in the lower legs of a patient with drug intoxication. After cannabis consumption, the patient fell asleep sitting cross-legged. During our first examination several hours later, the signs of compartmental syndrome with spontaneous pain, turgid swelling and paresis were present. Bilateral skin incision technique was used to gain entrance into the four compartments in both lower legs. Immediately after the operation, the patient showed crush syndrome with high serum creatine kinase activity 140.501 U/l and acute renal failure caused by rhabdomyolysis. Within 2 weeks of haemofiltration and dialysis, a full recovery to a normal serum creatinine level of 0.7 mg/dl was achieved. After emergency treatment and rehabilitation, the patient showed neither vascular nor neural defects.

Degree of carotid artery stenosis. Comparison of selective and non-selective angiographic findings with surgical specimens

OBJECTIVE

To compare the degree of vessel narrowing seen on selective and non-selective carotid artery catheter angiograms using criteria set by NASCET and ECST with the results obtained from corresponding surgical specimens.

SUBJECTS

In 40 preoperative angiograms (20 non-selective, 20 selective) the 'distal' degree of internal carotid artery (ICA) stenosis according to NASCET criteria and the 'local' degree of stenosis according to ECST criteria was assessed. These data were compared with the 'distal' and 'local' degree of ICA stenosis obtained by measuring the specimens and the diameter of the distal ICA intraoperatively.

RESULTS

The median 'local' degree of stenosis was 86.5% in the specimen and 83.5% in the selective angiograms (difference not significant). In non-selective angiography the median 'local' degree of stenosis was 77.5% compared to 84% in the corresponding specimens (P < 0.01). The median 'distal' degree of stenosis in selective angiography was 76.5 versus 75.5% in the specimens (n.s.). The median 'distal' degree of non-selective angiography was 67% compared to 77.5% in the corresponding specimens (P = 0.02). The trend to underestimate high grade stenosis (above 90%) was more pronounced in non-selective than in selective angiography. Medium grade stenosis (60-80%) was slightly overestimated in selective angiography.

CONCLUSION

Selective angiography is more accurate in determining the 'true' degree of stenosis in internal carotid artery disease, taking into account a slight overestimation of medium grade stenosis. High grade stenosis is underestimated in both selective and non-selective angiography. These observations extend to both the ECST and NASCET criteria of measuring the degree of stenosis, which differ by about 10%.

Morphometry and classification in abdominal aortic aneurysms: patient selection for endovascular and open surgery

PURPOSE

To evaluate the anatomic morphology of abdominal aortic aneurysms (AAAs) and compose a classification system to facilitate patient selection for endovascular graft (EVG) repair.

METHODS

Data on 242 consecutive AAA patients evaluated on a nonemergent basis in a 3.5-year period to July 1996 were prospectively entered into a registry. Patients were examined using sequential intravenous spiral computed tomographic angiography and intraarterial digital subtraction angiography. The data collected and analyzed included: diameters of the supra- and infrarenal aorta, aneurysm, aortoiliac bifurcation, and iliac arteries; lengths of the proximal neck, distal cuff, and aneurysm; degrees of iliac artery tortuosity; and occlusion of the visceral, renal, or iliac arteries.

RESULTS

The 242 aneurysms could be easily grouped into three distinctive categories related to the extent of the aneurysmal disease. Type I AAAs (11.2%) had nondilated, thrombus-free infrarenal (15 mm) necks and distal (10 mm) cuffs appropriate for EVG anchoring. In type II and its subgroups (72.3%), a sufficient proximal neck was present, but the aneurysm extended into the iliac arteries; 56% of these were eligible for a bifurcated endograft. In type III (16.5%), a sufficient proximal neck was missing, independent of distal involvement. In all, 51.7% were good EVG candidates based on AAA morphology. Taking into consideration relevant concomitant vascular diseases, proximal iliac kinking, and iliac, renal, or visceral occlusive disease, only 30.2% of the population were potential candidates for an efficient and secure EVG repair using the devices currently available.

CONCLUSIONS

In contrast to classical open repair, detailed preoperative measurements are recommended for EVG planning. The use of liberal EVG indications may lead to a higher incidence of complications, whereas restrictive morphology-based selection criteria may offer excellent results.

Pedal bypass for limb-threatening ischaemia: an 11-year review

Fifty-six patients with limb-threatening ischaemia had pedal revascularization with either autologous vein (n = 39) or sequential composite graft with a 6-mm polytetrafluoroethylene prosthesis and autologous vein (n = 17); 75 per cent had gangrene and skin necrosis and 25 per cent had ischaemic rest pain alone. Twelve grafts occluded within the first week, and resulted in major amputation in eight patients after unsuccessful revision. Two patients required amputation for persistent ischaemia despite a patent bypass. One patient died from bowel perforation (2 per cent). In 47 (84 per cent) of the 56 patients limb and life were preserved. The primary patency rate after 1, 2 and 4 years was 65, 55 and 55 per cent respectively, the secondary patency rate was 71, 62 and 62 per cent, and cumulative limb salvage rates were 77, 71 and 66 per cent. Life-table survival rates during follow-up (median 25 (range 0-112) months) were 89, 78 and 52 per cent respectively after 1, 2 and 4 years. Thirteen of 21 patients who died during follow-up did not require major amputation. Pedal reconstruction with autologous vein provides limb salvage until death in nearly two-thirds of patients with critical limb ischaemia resulting from crural arterial occlusive disease.

[The accuracy of angiography and CT angiography of the carotid bifurcation compared to macro-morphological correlation]

PURPOSE

To compare the degree of carotid artery stenosis in angiography and CT angiography with the degree of stenosis measured in an intact eversion endarterectomy specimen.

METHODS

Preoperative angiograms (intraarterial DSA, 512 x 512 matrix) and CT-angiograms (24 sec spiral scan, slice thickness 2 mm, pitch 1.5) were taken in 12 patients with symptomatic carotid stenosis. Evaluation of the degree of stenosis was performed according to the NASCET ("distal" degree) and ECST ("local" degree) methods. These data were compared with measurements of the surgical specimens.

RESULTS

The median "local" degree of stenosis in angiograms was 81.5% (range: 70-99%), in CT angiograms 83% (59-94%) and in specimens 85.5% (65-96%). The "distal" degree of stenosis was 79% (50-99%) in angiograms, 85.5% (55-99%) in CT angiograms and 81% (52-95%) in specimens. CT angiography slightly overestimated the degree of stenosis compared with the specimen, whereas angiography slightly underestimated the true degree of stenosis. However, these differences were not statistically significant.

CONCLUSION

CT angiography is able to predict the degree of internal carotid stenosis when compared with an intact surgical specimen. It is as accurate as the "gold standard" of invasive angiography.

[Prospective preoperative morphometry of abdominal aortic aneurysms: selective patient management for endovascular surgery]

The objective of this prospective clinical investigation of 205 elective abdominal aortic aneurysm (AAA) patients over a 3-year period. 1993-1995, was both to evaluate the morphology and aortic dimensions of AAA as a management decision for patient selection for endovascular grafting and to correctly plan the custom-made TPEG size and shape prior to the procedure.

[Infrarenal abdominal aortic aneurysm: morphological classification as decision aid for therapeutic procedures]

This clinical trial aimed to prospectively investigate the morphological structure of infrarenal abdominal aortic aneurysms (AAA) to establish a valid dataset in the preoperative assessment supporting either the conventional or endovascular (TPEG) surgical approach. Regarding both the general feasibility testing and safe TPEG placing, all the anatomic AAA data must already be measured preprocedurally, due to the necessity for conversion as a frequent consequence of an intraprocedural failure. Between January 1993 and June 1995, all the patients (n = 159) admitted for elective AAA repair, were prospectively analysed. Graded on the basis of these measurements we developed a new AAA classification system supporting the kind of the surgical procedure (standard) approach vs. TPEG). Three different types of AAA were clearly defined. Due to morphological AAA criteria, 86 out of 159 patients (54.1%) might be suitable for TPEG (Type I, IIA and IIB). An infrarenal (proximal) neck < 15 mm, an infrarenal aortic diameter > 24 mm or an extension of the aneurysm to the iliac bifurcation are considered to be exclusion criteria for TPEG placement. In consideration of relevant co-morbidities (e.g. renal artery stenosis, SMA occlusion, iliac occlusive disease, simultaneous operations) only 43 out 159 patients (27.1%) were good candidates for TPEG. In general, smaller AAA are more appropriate for TPEG repair due to better proximal and distal fixation. As a consequence, indication criteria for AAA repair must not be expanded to smaller AAA.

[Carotid TEA and perioperative thrombolysis: a new concept in therapy of acute ischemic stroke]

In seven carotid-related acute hemispheric strokes with simultaneous embolic occlusion of the middle cerebral artery thrombolysis with urocinase or rt-PA was performed preoperatively (n = 3) or intraoperatively (n = 4) after carotid endarterectomy. Four patients recovered totally, three patients showed a remarkable improvement and were able to walk postoperatively. The combination of carotid endarterectomy and thrombolysis (simultaneous or staged) is a new option in the emergency treatment of an acute carotid-related stroke and should be evaluated in prospective interdisciplinary studies.

Clinical effects of intravenous iloprost in patients with intermittent claudication

In a randomized patient-blind study iloprost or hydroxy-ethyl starch 200/0.5 were given i.v. 5 h daily for 2 weeks to 24 patients suffering from severe intermittent claudication due to peripheral vascular disease. An increase in pain-free walking distance of more than 50% occurred in 6 of 11 patients after the iloprost infusions and in 7 of 12 patients after HES treatment. No significant effects on haemodynamic or clinical chemistry tests were observed.