Effects of Carotid Endarterectomy on Cerebral Reperfusion and Cognitive Function in Patients with High Grade Carotid Stenosis: A Perfusion Weighted Magnetic Resonance Imaging Study.

OBJECTIVE: To investigate the influence of carotid endarterectomy (CEA) on cerebral perfusion and cognitive function in patients with internal carotid artery stenosis (ICA). METHODS: Patients were prospectively enrolled in this study. Shunted patients were excluded. Cerebral perfusion was measured by magnetic resonance (MR) perfusion weighted imaging (PWI) and diffusion weighted imaging (DWI) in 46 patients with >65% ICA (31 males, 64.5 ± 6.7 years) 1 week before and 6 weeks after CEA. Cognitive function was assessed using the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) 1 week before and 6 weeks after CEA. RESULTS: After CEA, perfusion parameters from PWI decreased, including mean transit time (MTT) (21.07 ± 7.36 vs. 14.27 ± 6.22, p < .0001), time to peak (TTP) (28.69 ± 8.54 vs. 23.45 ± 4.25, p = .001), arrive time (T0) (19.89 ± 7.32 vs. 15.20 ± 3.51, p = .001), and relative cerebral blood volume (rCBV) (11.48 ± 3.50 vs. 7.53 ± 3.17, p < .0001). A significant improvement was observed in MoCA (20.48 ± 1.70 vs. 22.04 ± 1.48, p = .001). Spearman's rank correlation analysis between TTP and MoCA scores demonstrated a linear relationship with an excellent correlation coefficient (R = -.893, p < .001). Linear regression indicated that diabetes was a risk factor for cognitive improvement in patients with ICA (p = .014). Further analysis showed that patients with DM performed worse in MoCA after the procedure (with-DM 21.15 ± 1.28 vs. non-DM 22.4 ± 1.46, p = .010) while the baselines were similar (non-DM: 20.3 ± 1.8 vs. with-DM: 20.9 ± 1.4, p = .362). CONCLUSION: CEA could improve the cerebral perfusion and the cognitive function in un-shunted ICA patients. Cerebral reperfusion was an important factor for cognitive improvement. Diabetes had a negative effect on cognitive improvement after CEA.

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial.

OBJECTIVES: Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year. METHODS: The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB. RESULTS: Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062). CONCLUSIONS: Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

From clinical trials to clinical practice: 612 cases treated with the Powerlink stent-graft for endovascular repair of AAA.

AIM: Most endovascular stent-grafts in endovascular aortic aneurysm repair (EVAR) are designed to deploy from the renal artery level down to the iliac level. The Powerlink device (Endologix Inc, Irvine, Calif) can be deployed from the iliac level up to the renal artery level. The aim of this study was to summarize our clinical experience of EVAR using the Powerlink device. METHODS: The fully-supported unibody bifurcated Powerlink stent graft was deployed sitting onto the abdominal aortic bifurcation (termed anatomical fixation), a proximal long cuff with or without Palmaz stent may follow the above procedure if necessary. We applied this strategy in most of our cohort. The data of 612 eligible abdominal aortic aneurysm (AAA) patients underwent endovascular repair between 1999 and 2008 using the Powerlink System at our institution were analyzed. Meanwhile, the US and French clinical trials results were enrolled for comparison. RESULTS: Among the 612 patient cohort, 99 cases (16%) completed between 1999 and 2004 had the endograft deployed from the renal artery downward. The remaining 513 cases (84%) completed afterwards had the bifurcated stent graft deployed onto the native bifurcation. Among the 513 cases, 146 cases (28%) were deemed as challenging anatomy with short or angulated neck. Technical success was achieved in 98.5% of patients (603/612). Intraoperative conversion occurred in 9 patients, 8 of which were due to delivery access failure and 1 due to rupture. Intraoperative complications included iliac or femoral patching in 5.1% of patients and iliac-femoral graft interposition in 0.3% of patients. Perioperatively, 3 deaths occurred, 2 limb occlusions were encountered. After 30 days and through current follow-up (mean: 5.2 years; maximum: 9.5 years), 1 rupture and 7 migrations occurred, all of which were in patients in whom the device was fixed at the level of the renal arteries. The rates of late conversion in the renal fixation and anatomical fixation groups were 4.0% and 1.9%, respectively. Likewise, the cumulative rates of type I proximal endoleak in the renal fixation and anatomical fixation groups were 5.0% and 1.2%, and respectively. Cumulative rates of all-cause mortality, limb occlusion, and type II endoleak were similar among implant groups. Remarkably, no stent fracture, graft disruption, or type III or type IV endoleak has been observed in any patient to date. Through current follow-up, 96% of patients are free from aneurysm sac diameter increase. CONCLUSIONS: Results from multiple clinical trials and our clinical practice proved that the Powerlink device is simple to implant, effective to endovascular repair, durable to mid- and long-term follow up. The implanting technique of combination of an anatomically-fixed unibody Powerlink device and proximal extension sealing leads to a superior outcome, even in challenging anatomy cases deemed unsuitable for endovascular repair. With this intuitive approach, migration and the associated sequelae were virtually eliminated.

Seven years' single center experience of Powerlink unibody bifurcated endograft for endovascular aortic aneurysm repair.

AIM: To assess the 7-year results of endovascular aortic aneurysm repair using the Powerlink unibody bifurcated endovascular stent-graft in our single center. METHODS: A prospective, nonrandomized trial was conducted in our unit within 7 years. Endovascular aortic aneurysm repair (EVAR) was planned, performed and followed-up by a fixed endovascular specialized group, including 2 vascular surgeons and 1 interventional radiologist. All the relative data were input into the SPSS statistical analysis software. All patients received abdomen X-ray plain films and CTs or duplex before discharge and 1 month, 6 months, 1 year after discharge, and then annually. RESULTS: From February 1999 to September 2006, a total of 378 abdominal aortic aneurysms (AAAs) patients were intended to treat with Powerlink device, 372 cases were implanted successfully, the technical success rate was 98.4%. The average operation time was 66 min (range, 35-150 min). The late 210 cases (56.5%) were implanted sitting on the aortic bifurcation, the other 162 early cases (43.5%) were not implanted sitting on the aortic bifurcation, proximal cuff was implanted in 209 cases (56.2%), and distal limb extension was used in 42 cases (11.3%), 22 cases (5.9%) received Palmaz stent. One hundred and ninety- four cases (52.2%) had infrarenal fixation, 178 cases (47.8%) had suprarenal fixation. Intraoperative complications included immediate conversion in 6 cases (1.6%), primary proximal type I endoleak in 8 cases (2.2%), primary distal type I endoleak in 2 cases (0.5%), type II endoleak occurred in 20 cases (5.4%). Mean follow-up was 26.7 months (range 1 month 7 years). Postoperative complications included secondary type I endoleaks in 10 cases (2.7%), secondary type II endoleaks in 9 cases (2.4%), limb occlusion in 8 cases and limb stenosis in 5 cases, endograft limb kinking/twisting in 2 cases, partial renal infarction in 9 cases (2.4%). A total of 7 cases (1.9%) had distal migration and all 7 cases were not implanted sitting on the aortic bifurcation. Post-EVAR conversion occurred in 6 cases (1.6%). There were a total of 18 deaths (4.8/%) and 6 deaths (1.6%) within 30 days. CONCLUSIONS: The Powerlink device is safe and effective in preventing AAA rupture in mid-term. It proved simple and easy for size choice. The unique design of this device may confer some advantages in terms of durability. The distinct anatomic fixation of stent-graft sitting on the aortic bifurcation simplifies the deployment procedures and minimizes the potential of distal migration. Prospective longer follow-up in multicenter randomized controlled larger series is necessary to confirm the encouraging outcomes.

Complications of carotid artery stenting.

AIM: The aim of this study was to deal with complications that can be managed by vascular surgery. METHODS: From March 2000 through May 2004, 171 patients (112 male, 59 female, mean age 66.2 years) underwent carotid artery stenting (CAS). Of these 171 interventions, 154 were CAS with percutaneous trasluminal angioplasty (PTA), 5 CAS without PTA, and 12 patients had only a PTA. RESULTS: In 171 patients who received CAS, 5 suffered a stroke within 7 days and 3 a transient ischemic attack. Twenty-one percent of the patients developed an in-stent restenosis >50% within 6 months following the intervention. Twenty-two patients with a recurrent in-stent restenosis were treated by re-PTA. Eight patients of this group of 22 re-PTAs developed a recurrent in-stent restenosis. They were converted with patch angioplasty or PTFE interposition. These 8 conversions were performed without morbidity or mortality. CONCLUSIONS: The preferable operative technique in patients with recurrent in-stent restenosis is open conventional operation with stent removal and patch angioplasty or graft interposition. The procedure can be performed at a low risk. In our series, we had no morbidity and mortality, and no cranial nerve lesion.

The event-related P300 potential approach to cognitive functions of nondemented patients with cerebral and peripheral arteriosclerosis.

OBJECTIVES: To detect subtle cognitive dysfunction in non-demented patients with either cerebral (cAD) or peripheral (pAD) arteriosclerotic disease, and to evaluate in these patients the effects on cognitive functions of carotid endarterectomy and bypass surgery, respectively. DESIGN: Case-control study. SETTING: Tertiary care referral center. PARTICIPANTS: Eighty consecutive patients with moderate to high-grade stenosis of the internal carotid artery (ICA) (mean age +/- SD, 62 +/- 8 years), 53 patients with stenoses of the peripheral arteries (60 +/- 10 years), and 80 healthy volunteers (58 +/- 15 years) enrolled in a study on healthy aging. Cerebral and peripheral arteriosclerotic disease was verified by digital subtraction angiography, and all patients were screened for confounding effects of concomitant diseases. MAIN OUTCOME MEASURES: Cognitive functions by event-related visual P300 potentials. RESULTS: Patients with cAD showed prolonged P300 latencies and reduced P300 amplitudes, whereas pAD patients had reduced P300 amplitudes only. On an individual scale, 25% of cAD patients, but only 6% of pAD patients, revealed P300 abnormalities. In the cAD, but not in the pAD patients, the P300 latencies were especially prolonged in the older patients, but other factors such as sex, cerebral symptoms, degree of ICA stenosis, and premorbid intelligence did not play any role in either group. Within 1 to 2 weeks of surgery, the P300 latencies shortened in both cAD and pAD patients with high initial values. CONCLUSIONS: As demonstrated by P300 potentials, even nondemented arteriosclerotic patients reveal signs of subtle cognitive dysfunction affecting especially the older cAD patient. In the short-term, carotid endarterectomy presumably improves cognitive functions unspecifically in nondemented patients with a higher initial degree of P300 abnormality.

[Post-traumatic findings in the cerebral arteries in the neck (author's transl)]. / Posttraumatische Befunde an Hirnarterien im Halsbereich.

Starting from the observation of a post-traumatic thrombosis in the cervical portion of the carotid artery, with two subsequent similar findings, it is shown that angiography is of special importance in assessing these cases. Investigation of the cervical region of this artery should be considered in all cases of skull and cerebral trauma. On the other hand, the cases described by Sullivan show that the presence of a carotid lesion must be considered in all multiple injuries, just as injuries to vessels and organs must be excluded in patients with intracranial haematomas. Consultation between physician and radiologist is necessary for all injured patients in order not to omit any important steps during angiography.

[Imaging of aortic endoprostheses and their complications]. / Bildgebung von Aortenendoprothesen und deren Komplikationen.

PURPOSE: To determine the optimal postoperative imaging modality for the follow-up of patients with endoluminal aortic stent grafts. MATERIAL AND METHODS: From August 1994 to November 1997, 214 patients (194 male and 20 female) with abdominal and thoracic aortic aneurysms were treated with endovascular stent grafts. 137 patients (129 male, 8 female) with 89 tube grafts and 48 bifurcated grafts (45 EVT, 88 Stentor/Vanguard, 3 Chuter, 1 Talent) were evaluated with contrast-enhanced spiral-CT, duplex ultrasound, and DSA at a mean follow-up of 11.1 months. RESULTS: We found 12 persistent primary endoleaks (8.8%), 17 secondary endoleaks (12.4%), 8 limb occlusions (5.8%), 28 endoluminal thrombi lining the stent graft (20.4%), and 26 suture breakages of the stent frame (19%). In 9 patients (6.6%) the proximal end of the stent partially covered the renal arteries. In 3 patients (2.2%) a partial renal infarction was seen. Spiral-CT was able to demonstrate all the above changes except for 3 sidebranch endoleaks that were documented by duplex ultrasound only and 8 suture breaks seen on abdominal plain films only. The median aneurysm diameter decreased from 48 mm pre-operatively to 46 mm at 24 months post-operatively in patients with endoleaks and from 44 mm to 36 mm in patients without endoleak. For several patients the decreasing aneurysm diameter did not reliably correlate with complete exclusion of the aneurysm. CONCLUSION: For follow-up of endoluminal aortic stent grafts contrast-enhanced spiral-CT is superior to duplex ultrasound. DSA is necessary only for patients with complications requiring a secondary intervention.

Late results after extra-anatomic bypass routes.

The long-term results of 37 carotido-subclavian grafts was 100% till the end of the third year. This method is now our preferred method for correction of subclavian lesions. The operative mortality was 0%. The long-term results of the femoro-femoro bypasses was 79.7% from the third through the fifth year. 5 out of 7 axillo-femoral grafts remained patent. In our opinion the axillo-femoral bypass should only implanted in patients with an infected area in the aortoiliac segment but not routinally.

Our experience of surgery for innominate and subclavian lesions.

Since 1965 we have performed 67 operations to correct a subclavian steal-syndrom. Mortality after transthoracic correction in 30 patients was 6.7%, but we lost no patient after 37 extrathoracic reconstructions. The long-term results in these reconstructive procedures were excellent with a patency of 94.7% from the forth through the fifth year after transthoracic approach. Over 90% of the patients were asymptomatic or improved.

Long-term results of femoro-popliteal/tibial bypasses with special references to re-operation in former femoro-popliteal procedures.

Since 1962 a total of 1,361 femoro-popliteal/tibial reconstructions have been performed and followed up. In addition to the saphenous vein, Dacron, PTFE, and umbilical vein grafts were used. The following long-term results were achieved: The saphenous vein grafts have a patency of 73.6% after 10 years and of 52.2% after 17 years. Cumulative patency rate for the PTFE grafts were 76.4% after 39 months with above knee and 62.2% after 2 years with below knee reconstructions. After 12 months 85.7% of the umbilical vein grafts were functioning.

The tibio-peroneal reconstruction in reocclusions after femoro-popliteal procedures.

After a reocclusion of the femoro-popliteal segment with run-off problems, there is frequently still the possibility of a crural revascularisation. After an exact pre- or intra-operative angiography, there is a choice to reconstruct the tibio-peroneal trunk by autologous saphenous vein graft, composite graft and, if a vein is not available, with the PTFE prosthesis or umbilical vein.

Late results with Dardik-biograft in peripheral arterial surgery.

A total of 117 vascular reconstructions below the inguinal ligament were performed using Dardik's human umbilical vein. The indication for surgery was limb salvage in 91.5%. In 61.5% a previous reconstruction had failed. The distal anastomosis was done with the popliteal artery above the knee in 9 cases, below the knee in 41, and with a tibial or the peroneal artery in 60 cases. The umbilical vein was combined with a prosthesis or the autologous saphenous vein in 20 cases. The cumulative patency rates of all reconstructions were 59.6% after 3, and 46.7% after 6 years. Crural reconstructions had a cumulative patency rate of 52% 3 years after surgery. The main factors influencing patency were the preoperative grade of ischemia, the site of the distal anastomosis and the angiographic run-off. It is concluded that the human umbilical vein is the graft material of choice in long length revascularization whenever the saphenous vein is not available.

Surgical treatment of renal artery occlusive disease: long term results.

68 patients were operated on for renal artery occlusive disease. After a mean follow-up of 61 months renovascular hypertension was cured or markedly improved in 79.2%. The results depended mostly on the duration of preexisting hypertension and on the histology of the renal artery lesion. Forty-four months after surgery, 37 reconstructions were examined by angiography. Mostly digital subtraction technique was used. Total occlusion rate was 24%. Patency rates of autogenous vein bypass grafts were similar to prosthetic grafts. It is concluded that prosthetic grafts like PTFE are a reasonable alternative in aortorenal bypass procedures.

Digital transvenous angiography in follow-up examinations after carotid reconstruction: early results.

A total of 187 check-up examinations by DVSA were carried out after various types of carotid reconstructions. The results were inconclusive in only 2.7% of the cases. A good or very good postoperative result could be demonstrated in 77.5%. A slight stenosis was present in 16%, a significant stenosis in 2.7% and a complete occlusion of the internal carotid artery in 1.1%. Patch plasty alone showed the best results followed by endarterectomy and endarterectomy with patch plasty. Segmental carotid resections and dilatations led to the poorest results. Most of those cases, where a stenosis recurred, it was already present immediately after the operation and only rarely caused by progression of the basic disease or intimal proliferation. The complication rate of DVSA was low. It is concluded that DVSA is a low risk and reliable method which can routinely be used in the postoperative evaluation of patients with carotid reconstructions.

Composite grafts: an alternative to saphenous vein for lower extremity arterial reconstruction.

In the absence of adequate saphenous vein for femoral-popliteal/infrapopliteal bypass grafts, composite grafts constructed with PTFE (Gore-tex) and short segments of autogenous tissue were utilized. The composite grafts (208 cases) were compared to plain PTFE (Gore-tex) grafts (235 cases) and to the literature results reported for saphenous vein grafts (2,108 cases) in limb salvage situations. Evaluation using life table analysis with followup extending to 63 months indicates composite grafts yielded favorable results when compared to the "gold standard" of saphenous vein and superior results to plain PTFE (Gore-tex) grafts for infrapopliteal bypass. A combined, dual center approach was chosen to enhance significance by expanding the number of patients evaluated and extending the period of followup from earlier studies reported separately from each center.

Intraoperative angioscopy after carotid endarterectomy.

The angioscopic evaluation of the carotid bifurcation has proved valuable for intraoperative quality control after carotid endarterectomy (CEA). From January 1989 to July 1990, intraoperative angioscopy was performed in 196 patients undergoing CEA. We used a 2.2, 2.8 or 3.6 mm angioscope inserted at the end of the CEA through the remaining opening in the suture line. The angioscopic findings were classified as follows: I--no pathology (68%), II--thrombi, smaller debris, suture irregularities (29%), III--intima flap, endoscopic removal (3%), IV--intima flap, surgical redo (3%). Our results support the practicability and importance of intraoperative angioscopy for surgical decision making. It is possible to rinse out thrombi or remove remaining debris using flexible forcepy, under direct visual control. There were no significant complications related to the angioscopic procedure.

Surveillance of patients after abdominal aortic aneurysm repair with endovascular grafting or conventional treatment.

At Nuremberg Southern Hospital we have been using endovascular therapy for aortic aneurysms for the past 3 years. Between August 1994 and August 1997, 193 patients with infrarenal aortic aneurysms were treated with endovascular stent grafts. Besides using commercially available modular systems of the Stentor type (MinTec/Vanguard*, Boston Scientific) we also participated in a multicenter study implanting EGS devices (EVT in 65 patients). Follow-up examinations must strive to detect thrombotic complications as well as endoleaks with high sensitivity and specificity. To avoid aneurysm rupture significant increase in aneurysm diameter must be detected in a timely fashion to select patients for additional corrective endovascular procedures or conversion to open surgical therapy. A close follow-up regimen therefore is absolutely mandatory for all patients undergoing endovascular aortic grafting, particularly when new prosthetic devices are being introduced. Prosthetic devices that have been adequately tested using controlled study designs and are commercially available may be followed-up using a standardized follow up scheme as delineated. Particularly during the first postoperative year color duplex with use of an intravenous ultrasound enhancing agent has been used successfully to detect even minor endoleaks originating from retrograde perfusion via aortic side branches (lumbar or inferior mesenteric artery). Only patients with documented endoleaks or suspected outflow obstruction requiring further intervention need to undergo diagnostic arteriography. After conventional aneurysm repair yearly duplex scans are usually sufficient to follow the normal patient. Patients who have undergone endovascular therapy, however need to be followed much closer using duplex as well as abdominal CT scans. This will logically result in significantly higher follow up costs. Periinterventional costs of endovascular aortic reconstruction currently exceed those of conventional aortic repair by approximately 50%. Given the current health care finance situation it is questionable whether endovascular therapy of abdominal aneurysm will become standard practice in Germany.

[Rare vascular complications after resection of goiters]. / Seltene vasculäre Komplikationen nach Strumaresektion.

Two patients developed a neurological deficit after an iatrogenic lesion of the common carotid artery in thyroid gland resection. In one patient the artery could be successfully reconstructed by graft interposition. In every patient who develops a neurological deficit after thyroid gland resection a lesion of the carotid artery should be reminded.

[Late results after extra-anatomical shunt surgery in vascular surgery]. / Spätergebnisse nach extraanatomischen Umleitungsverfahren in der GefäBchirurgie.

Alternative procedures were applied in high-risk patients or, in cases in which it was necessary, to bypass infected vascular beds. Some of our 113 procedures, especially the carotid-subclavian and the femoro-femoral grafts, showed excellent long-term results and wider application of these operations thus appears justified. Infected areas in the groin may be bypassed by the lateral iliaco-femoral graft as an alternative to the obturator bypass.