(1/180) A policy of quality control assessment helps to reduce the risk of intraoperative stroke during carotid endarterectomy.

OBJECTIVES: A pilot study in our unit suggested that a combination of transcranial Doppler (TCD) plus completion angioscopy reduced incidence of intra-operative stroke (i.e. patients recovering from anaesthesia with a new deficit) during carotid endarterectomy (CEA). The aim of the current study was to see whether routine implementation of this policy was both feasible and associated with a continued reduction in the rate of intraoperative stroke (IOS). MATERIALS AND METHODS: Prospective study in 252 consecutive patients undergoing carotid endarterectomy between March 1995 and December 1996. RESULTS: Continuous TCD monitoring was possible in 229 patients (91%), while 238 patients (94%) underwent angioscopic examination. Overall, angioscopy identified an intimal flap requiring correction in six patients (2.5%), whilst intraluminal thrombus was removed in a further six patients (2.5%). No patient in this series recovered from anaesthesia with an IOS, but the rate of postoperative stroke was 2.8%. CONCLUSIONS: Our policy of TCD plus angioscopy has continued to contribute towards a sustained reduction in the risk of IOS following CEA, but requires access to reliable equipment and technical support. However, a policy of intraoperative quality control assessment may not necessarily alter the rate of postoperative stroke.  (+info)

(2/180) Intraoperative assessment of technical perfection in carotid endarterectomy: a prospective analysis of 1305 completion procedures. Collaborators of the EVEREST study group. Eversion versus standard carotid endartectomy.

OBJECTIVE: to define the incidence of technical defects and the impact of technical errors on ipsilateral carotid occlusion, ipsilateral stroke, and early restenosis rates, we analysed 1305 patients undergoing carotid completion procedures. DESIGN: prospective multicentre study. PATIENTS AND METHODS: adequacy of CEA was assessed intraoperatively by angiography in 1004 (77%), by angioscopy in 299 (22%), and by duplex scan in two patients (1%). Arteriograms and angioscopic findings were interpreted at the time of the procedure by the operating surgeon, who also established the need for immediate surgical revision. RESULTS: perioperatively, 13 major strokes (0.9%, all ipsilateral) and six deaths (0.4%) were recorded. Overall, 112 defects (9%) were identified intraoperatively: 81 (72%) were located in the common carotid artery (CCA) or internal carotid artery (ICA), and 31 (28%) in the external carotid artery. In 48 patients (4%) the defects were revised. Logistic regression analysis revealed that carotid plaque extension >2 cm on the ICA was a positive independent predictor of CEA defects (odds ratio (OR) 1.5p=0.03). A significant association was found between the incidence of revised defects of the CCA and ICA and perioperative ipsilateral stroke (OR 11.5p=0.0002). In contrast, patients with minor non-revised defects had an ipsilateral stroke rate comparable to that of patients with no defects (p=0.4). No significant association was found between revised or non-revised defects and occurrence of restenosis/occlusion at 6-month follow-up. CONCLUSIONS: the incidence of major technical defects during CEA is low, yet the perioperative neurological prognosis of patients with major defects warranting revision is poor. Completion angiography or angioscopy and possible correction of defects did not protect per se from an unfavourable early outcome after CEA. Therefore, surgical excellence is mandatory to achieve satisfactory results after CEA.  (+info)

(3/180) Valvulotomy of non-reversed saphenous vein bypass grafts: a randomised, blinded, angioscopy-controlled study.

OBJECTIVES: to compare the result of vein valve disruption with two different valvulotomes during non-reversed saphenous vein bypass. DESIGN: a randomised, blinded clinical study. MATERIALS AND METHODS: twenty patients undergoing femorodistal non-reversed saphenous vein arterial bypass were randomised into two equal groups. Valve leaflet disruption was performed either with a standard size plastic valvulotome or with a metal valvulotome with an exchangeable cutting head. Valvulotomy was done after full exposure of the vein and completion of the proximal anastomosis. The result was evaluated by a surgeon blinded to the valvulotome used, using angioscopy. RESULTS: a total of 219 valve cusps were inspected with angioscopy. There were 83 completely lysed cusps (69%) by plastic and 76 (78%) by metallic valvulotomes (p=0.14). Of all the incompletely lysed cusps 12 (29%) occurred in the most proximal valve pocket treated with valvulotomy. CONCLUSIONS: no significant difference in performance between the investigated valvulotomes was found. Incomplete valvulotomy occurred mainly in the proximal part of the vein and was obviously caused by a size mismatch between the diameter of vein and the valvulotome. Construction of a valvulotome with a variable diameter cutting head is therefore recommended.  (+info)

(4/180) Evaluation of disinfection and sterilization of reusable angioscopes with the duck hepatitis B model.

PURPOSE: Nosocomial transmission of viral hepatitis and retrovirus infection has been reported. The expected risk is greatest for the hepatitis B virus (HBV). The duck HBV (DHBV) has similar biologic and structural characteristics to HBV and has been adopted as a suitable model for disinfectant testing. METHODS: Angioscopic examination of the external jugular vein was performed on DHBV-infected ducks. After use, the instrument was air dried for 3 minutes. Samples were obtained by flushing the channel with 5 mL of phosphate buffered saline solution. The samples were collected immediately after drying (control), after flushing with 5 mL of water, after glutaraldehyde disinfection for 5, 10, and 20 minutes, and after ethylene oxide gas sterilization. Angioscopes were either precleaned or uncleaned before disinfection/sterilization. Residual infectivity was assessed with inoculation of samples into the peritoneal cavity of day-old ducks (n = 231). RESULTS: DNA analysis results of liver samples showed that all 38 control ducks became infected. The frequency of DHBV infection was reduced to 93% (14 of 15) by flushing the angioscope with 5 mL of sterile water. No transmission occurred after the use of any of the properly precleaned and disinfected/sterilized angioscopes. However, after the use of the uncleaned angioscopes, the transmission rate was 90% (9 of 10) and 70% (7 of 10) after 5 and 10 minutes of contact time, respectively, in 2% glutaraldehyde. Even after the recommended 20 minutes of contact time, there was still 6% (2 of 35) transmission. After ethylene oxide sterilization, two of the recipient ducklings (2 of 35) were infected with DHBV. CONCLUSION: There was no disease transmission after reuse of disposable angioscopes adequately cleaned before disinfection or sterilization. However, if the angioscopes are inadequately cleaned, DHBV can survive despite glutaraldehyde disinfection or ethylene oxide sterilization. This contrasts with previous in vitro and in vivo data with solid surgical instruments. It is postulated that the presence of a narrow lumen or residual protein shielding within the lumen may compromise effective inactivation of hepadnaviruses on angioscopes, with the potential risk for patient-to-patient transmission.  (+info)

(5/180) Stent attachment site-related endoleakage after stent graft treatment: An in vitro study of the effects of graft size, stent type, and atherosclerotic wall changes.

OBJECTIVE: Perigraft endoleakage is a major complication of the endovascular treatment of abdominal aortic aneurysms. The factors that cause this form of endoleakage are not completely identified. The effect of sizing of the prosthesis in combination with either self-expandable or balloon-expandable stents is evaluated in this study. Further, the influence of atherosclerotic changes on endoleakage is evaluated. METHODS: Eight human abdominal aortas were assessed macroscopically at 11 sites for the presence of atherosclerotic changes with intravascular ultrasound scanning (IVUS) and with computed tomography (CT). Five aortas were placed in in vitro circulation with physiologic parameters. After the determination of the proximal and distal landing site of the stent graft, the diameter and surface measurements of the cross sections were taken. The stent graft diameters were chosen from 4-mm undersizing to 6-mm oversizing, both for Gianturco stent grafts (William Cook Europe A/S, Bjaeverskov, Denmark) and for Palmaz stent grafts (Cordis/Johnson & Johnston Co, Warren, NJ). After placement of the stent graft, the diameter and surface measurements of the aortic cross section were determined at the proximal and distal stent attachment sites. The presence and size of the folds at the stent attachment site and the interface with the aortic wall were determined with IVUS and angioscopy. Endoleakage was evaluated with angiography. After angioplasty of the stent attachment site, IVUS, angioscopy, and angiography were repeated. RESULTS: Regarding atherosclerotic changes of the aortic wall, the correlations between clinical impression and CT, clinical impression and IVUS, and CT and IVUS were high (r = 0.77, r = 0.79 and r = 0.79, respectively). For the Gianturco stent grafts, no significant relationship existed between the diameters measured before and after stent graft placement, leading to great differences in intended and achieved oversizing. The achieved oversizing was less in the case of minimal atherosclerotic changes of the aortic wall. The Gianturco stent graft followed the aortic wall closely during the heart cycle. The sizes of the folds of the fabric were clearly correlated with the achieved oversizing (r = 0.83; P =.04) and the grade of endoleakage (r = 0.88; P =.022). Angioplasty after stent graft placement had no effect on the diameter and the grade of endoleakage. Palmaz stent grafts did not follow the aortic wall during the heart cycle. A significant correlation existed between oversizing and both space between aortic wall and stent graft (r = -0.88; P =.02) and grade of endoleakage (r = 0.84; P =.036). Grade of endoleakage in the Palmaz stent graft group was less than in the Gianturco stent graft group. CONCLUSION: With the use of Gianturco stents, a great difference between intended and achieved oversizing is accomplished. The atherosclerotic changes of the aortic wall possibly affect this finding. The configuration of the Gianturco stent results in the formation of fold in the case of oversizing, which is associated with endoleakage. However, the self-expandable character of the stent leads to a close relation to the aortic wall during the heart cycle, and this may possibly accommodate future aortic neck dilation. The Palmaz stent grafts do not follow the aortic wall during the heart cycle, but they do lead to better interface between the graft and the aortic wall, which results in less endoleakage.  (+info)

(6/180) The use of arm vein in lower-extremity revascularization: results of 520 procedures performed in eight years.

PURPOSE: The absence of an adequate ipsilateral saphenous vein in patients requiring lower-extremity revascularization poses a difficult clinical dilemma. This study examined the results of the use of autogenous arm vein bypass grafts in these patients. METHODS: Five hundred twenty lower-extremity revascularization procedures performed between 1990 and 1998 were followed prospectively with a computerized vascular registry. The arm vein conduit was prepared by using intraoperative angioscopy for valve lysis and identification of luminal abnormalities in 44.8% of cases. RESULTS: Seventy-two (13. 8%) femoropopliteal, 174 (33.5%) femorotibial, 29 (5.6%) femoropedal, 101 (19.4%) popliteo-tibial/pedal, and 144 (27.7%) extension "jump" graft bypass procedures were performed for limb salvage (98.2%) or disabling claudication (1.8%). The average age of patients was 68.5 years (range, 32 to 91 years); 63.1% of patients were men, and 36.9% of patients were women. Eighty-five percent of patients had diabetes mellitus, and 77% of patients had a recent history of smoking. The grafts were composed of a single arm vein segment in 363 cases (69. 8%) and of spliced composite vein with venovenostomy in 157 cases (30.2%). The mean follow-up period was 24.9 months (range, 1 month to 7.4 years). Overall patency and limb salvage rates for all graft types were: primary patency, 30-day = 97.0% +/- 0.7%, 1-year = 80.2% +/- 2.1%, 3-year = 68.9% +/- 3.6%, 5-year = 54.5% +/- 6.6%; secondary patency, 30-day = 97.0% +/- 0.7%, 1-year = 80.7% +/- 2.1%, 3-year = 70.3% +/- 3.4%, 5-year = 57.5% +/- 6.2%; limb salvage, 30-day = 97.6% +/- 0.7%, 1-year = 89.8% +/- 1.7%, 3-year = 82.1% +/- 3.3%, 5-year = 71.5% +/- 6.9%. Secondary patency and limb salvage rates were greatest at 5 years for femoropopliteal grafts (69.8% +/- 12.8%, 80.7% +/- 11.8%), as compared with femorotibial (59.6% +/- 10. 3%, 72.7% +/- 10.5%), femoropedal (54.9% +/- 25.7%, 56.8% +/- 26.9%, ) and popliteo-tibial/pedal grafts (39.0% +/- 7.3%, 47.6% +/- 15.4%). The patency rate of composite vein grafts was equal to that of single-vein conduits. The overall survival rate was 54% at 4 years. CONCLUSION: Autogenous arm vein has been used successfully in a wide variety of lower-extremity revascularization procedures and has achieved excellent long- and short-term patency and limb salvage rates, higher than those generally reported for prosthetic or cryopreserved grafts. Its durability and easy accessibility make it an alternative conduit of choice when an adequate saphenous vein is not available.  (+info)

(7/180) Endovascular-assisted versus conventional in situ saphenous vein bypass grafting: cumulative patency, limb salvage, and cost results in a 39-month multicenter study.

OBJECTIVE: In this retrospective multicenter study, the results of a minimally invasive method of endovascular-assisted in situ bypass grafting (EISB) versus "open" conventional in situ bypass grafting (CISB) were evaluated with a comparison of primary and secondary patency, limb salvage, and cost. METHODS: Enrolled in this study were 273 patients: 117 underwent CISB (42 femoropopliteal, 75 femorocrural) and 156 underwent EISB (41 femoropopliteal, 115 femorocrural). EISB was performed with an angioscopic Side Branch Occlusion system and an angioscopically guided valvulotome. All the patients underwent follow-up examination with serial color-flow ultrasound scanning. RESULTS: Both groups had similar comorbid risk factors for diabetes mellitus, coronary artery heart disease, hypertension, and cigarette smoking. The primary patency rates (CISB, 78.2% +/- 5% [SE]; EISB, 70.5% +/- 5%; P =.156), the secondary patency rates (CISB, 84.1% +/- 4%; EISB, 82.9% +/- 5%; P =.26), and the limb salvage rates (CISB, 85.8%; EISB, 88.4%; P =.127) were statistically similar, with a follow-up period that extended to 39 months (mean, 16.6 months; range, 1 to 40 months). In veins that were less than 2.5 to 3.0 mm in diameter, the EISB grafts fared poorly, with an increased incidence of early (12-month) graft thromboses (CISB, 10 grafts, 8.5%; EISB, 24 grafts, 15.3%). However, wound complications (CISB, 23%; EISB, 4%; P =.003), mean hospital length of stay (CISB, 6.5 days +/- 4.83; EISB, 3.2 days +/- 3.19; P =.001), and mean hospital charges (CISB, $25,349 +/- $19,476; EISB, $18,096 +/- $14,573; P =.001) were all significantly reduced in the EISB group. CONCLUSION: The CISB and EISB midterm primary and secondary patency and limb salvage rates were statistically similar. In smaller veins (< 2.5 to 3.0 mm in diameter), however, EISB is not appropriate because overly aggressive instrumentation may cause intimal trauma, with resultant early graft failure. With the avoidance of a long leg incision in the EISB group, wound complications and hospital length of stay were significantly reduced, which lowered hospital charges and justified the additional cost of the endovascular instruments. When in situ bypass grafting is contemplated, EISB in appropriate patients is a safe, minimally invasive, and cost-effective alternative to CISB.  (+info)

(8/180) Minimally invasive approach for aortic arch branch vessel reconstruction.

Minimally invasive aortic arch branch vessel reconstruction was successfully accomplished in four patients over the past 3 years. There were no operative complications. Three patients had an uneventful hospital course, ranging from 3 to 5 days. The fourth patient with multiple medical problems and severe peripheral vascular disease had a prolonged hospital course for reasons unrelated to the surgical procedure. This minimally invasive surgical exposure can be used to effectively and safely repair innominate and left common carotid artery lesions.  (+info)