The Influence of Routine Completion Arteriography on Outcome following Carotid Endarterectomy

n = 69) normal; Group B (n= 29), abnormal, severe defects; Group C (n= 56), abnormal, mild–moderate defect. RCA detected 32 defects in Group B: 10 internal carotid (ICA), seven endpoint flaps, two kinks, one dissection; 16 external carotid (ECA), 10 severe endpoint defects and six total occlusion; six common carotid (CCA), five irregular proximal shelfs, one web. Thirty of 32 defects were successfully repaired as confirmed by normal repeat RCA studies; one ECA defect was not repaired and the ICA dissection was irreparable. In Group C, 67 mild–moderate defects were identified, but not corrected. These included <30% stenosis in the ICA (12), ECA (18), CCA (24), and vein patch corrugation or irregularity (13). For the entire series the postoperative ICA occlusion rate was 2% (3/154), stroke rate 2.6% (4/154), and a subsequent >50% restenosis rate of 7% (11/154). The yield from routine carotid completion arteriograms was significant, with 19% of studies identifying a severe defect that required repair. Although the difference in stroke rates and restenosis between the different groups did not reach statistical significance, patients with normal intraoperative arteriograms initially or after correction of a significant RCA defect had no early carotid occlusion (p= 0.05, Fisher's exact test) compared to patients with residual RCA defects. All early carotid occlusions occurred in patients with unrepaired defects. We conclude that RCA is an important method of quality control after CEA and exerts a subtle, but real, reduction in postoperative complications.     

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.     

Intraoperative carotid artery duplex scanning in a modern series of 650 consecutive primary endarterectomy procedures

PURPOSE: Thromboembolic complications after carotid endarterectomy are frequently associated with technical defects. We analyzed the effect of intraoperative duplex scanning in detection of significant but clinically unsuspected technical defects and residual common carotid artery (CCA) disease as a potential source of postoperative transitory ischemic attack (TIA) and stroke. METHODS: From April 2000 to April 2003, 650 consecutive primary carotid endarterectomy procedures were performed in 590 patients at a single institution by two vascular surgeons. Patients included 335 men (57%) and 255 women (43%). Indications for surgery were asymptomatic internal carotid artery (ICA) stenosis (>or=70%) in 464 patients (71%). All procedures were performed with the patient under general anesthesia, with synthetic patch angioplasty in 644 (99.1%). Major technical defects at intraoperative duplex scanning (>30% luminal internal carotid artery stenosis, free-floating clot, dissection, arterial disruption with pseudoaneurysm) were repaired. CCA residual disease was reported as wall thickness (0.7-4.8 mm; mean, 1.7 +/- 0.7) and percent stenosis (16%-67%; mean, 32% +/- 8%) in all cases. Postoperative 30-day TIA, stroke, and death rates were analyzed. RESULTS: There were no clinically detectable postoperative thromboembolic events in this series. All 15 major defects (2.3%) identified with duplex scanning were successfully revised. These included 7 intimal flaps, 4 free-floating clots, 2 ICA stenoses, 1 ICA pseudoaneurysm, and 1 retrograde CCA dissection. Diameter reduction ranged from 40% to 90% (mean, 67 +/- 16%), and peak systolic velocity ranged from 69 to 497 cm/s (mean, 250 +/- 121 cm/s). Thirty-one patients (5%) with the highest residual wall thickness (>3mm) in the CCA and 19 (3%) with the highest CCA residual diameter reduction (>50%) did not have postoperative stroke or TIA. Overall postoperative stroke and mortality rates were 0.3% and 0.5%, respectively; combined stroke and mortality rate was 0.8%. One stroke was caused by hyperperfusion, and the other occurred as an extension of a previous cerebral infarct. No patients had TIAs. Two deaths were caused by myocardial infarction, and one death by respiratory insufficiency. CONCLUSION: We believe intraoperative duplex scanning had a major role in these improved results, because it enabled detection of clinically unsuspected significant lesions. Residual disease in the CCA does not seem to be a harbinger of stroke or TIA.     

Surgical treatment of internal carotid artery occlusion

PURPOSE: Nonoperative treatment of recent internal carotid artery (ICA) occlusion is associated with increased recurrent stroke rates. We analyzed our results of carotid endarterectomy (CEA) for treatment of symptomatic recent ICA occlusion to evaluate its feasibility, safety, and outcomes. METHODS: From 1990 to 2002, all patients with transient ischemic attack (TIA), amaurosis fugax, and minor stroke underwent duplex ultrasound (US) scanning and arteriography to confirm the diagnosis of ICA occlusion. Within 2 weeks of symptom onset, patients underwent operative exploration with attempted CEA. ICA occlusion was detected at preoperative angiography and confirmed at surgery. Patients with extensive ICA plaque not amenable to endarterectomy underwent external CEA with ICA ligation. RESULTS: Over 12 years, 87 patients with symptomatic ICA occlusion underwent 90 operations for ICA exploration. In 30 patients (18 men, 12 women) with TIA (45%), amaurosis fugax (19%), or minor stroke (36%), CEA to treat ICA occlusion was technically successful. There was 1 postoperative stroke, 2 asymptomatic internal carotid occlusions, and no restenoses (mean follow-up, 26 months; range, 1-93 months). In 57 patients (37 men, 20 women) with TIA (41%), amaurosis fugax (27%), or stroke (32%) in whom CEA was unsuccessful, external CEA was performed. In this group there were no postoperative strokes, 2 asymptomatic external carotid artery occlusions, and 1 restenosis (>70%) (mean follow-up, 22 months; range, 1-73 months). There were no late strokes in either group. CONCLUSION: Operative exploration and endarterectomy to treat symptomatic ICA occlusion is feasible and safe. Patients with symptomatic ICA occlusion should be considered candidates for CEA.     

Relationship between intraoperative color-flow duplex findings and early restenosis after carotid endarterectomy: A preliminary report

Purpose: This study was undertaken to examine the relationship between intraoperative color-flow duplex (CFD) findings and the development of restenosis in patients undergoing carotid endarterectomy (CEA).Methods: Seventy-eight patients (43 male and 35 female; mean age, 65 years) underwent 86 CEAs (eight staged bilateral) and intraoperative CFD during a 31-month period. Three patients (three CEAs, 3%) underwent both CFD and a completion arteriographic scan. Patients were observed in a postoperative protocol using CFD surveillance. The follow-up interval ranged from 6 to 24 months (average, 12 months).Results: After undergoing CEA, 10 patients (10 CEAs, 11%) had an abnormality detected by intraoperative CFD; one was confirmed with a completion arteriographic scan. These abnormalities consisted of elevated peak systolic velocities (PSV) with a mosaic color pattern suggesting turbulence seen in six CEAs, including one internal carotid artery (ICA) with abnormal hemodynamics and an unremarkable completion arteriogram. Intimal defects on B-mode were seen in another four CEAs. These carotid arteries were reexplored, defects (intimal flaps with platelet thrombus) were confirmed by direct examination, and all were repaired with or without a patch (six ICAs, three external carotid arteries, and one common carotid artery). No cerebrovascular events occurred in the perioperative period. No carotid restenosis (≥50% diameter reduction) was identified during follow-up of 43 patients (48 CEAs, 56%). Two patients had recurrent neurologic symptoms.Conclusion: Intraoperative CFD is an effective test for detecting flow abnormalities or intimal defects in patients undergoing CEA. Ensuring normal intraoperative hemodynamics after CEA may be a major factor associated with decreased incidence of perioperative cerebrovascular events and subsequent carotid artery restenosis. (J Vasc Surg 1996;24:588-96.)     

Hemodynamic conditions at the carotid bifurcation during protective common carotid occlusion.

OBJECTIVES: Carotid angioplasty and stenting procedures are associated with an obligatory release of particulate debris into the distal cerebral circulation. Although most of the emboli are small and do not result in symptomatic neurologic deficits, some may be large enough to cause stroke. For this reason, a variety of filters and balloon occlusion devices have been employed as adjuvants to decrease the risk of distal embolization during carotid stenting. Some of these devices rely on the arrest of antegrade blood flow with the use of inflow arrest. The present study was undertaken to investigate the hemodynamic conditions that exist at the carotid bifurcation during common carotid artery (CCA) occlusion. METHODS: Internal carotid artery (ICA) and external carotid artery (ECA) stump pressures were measured in 29 patients undergoing carotid endarterectomy. Duplex ultrasound scanning was used to measure the direction and velocity of blood flow in the ICA and ECA with the CCA cross-clamped but the ICA and ECA open, a clinical scenario analogous to CCA balloon occlusion at the time of carotid angioplasty and stenting. The direction and magnitude of ICA and ECA flow were compared with the stump pressures to determine whether a correlation existed between these variables. RESULTS: The mean stump pressure in the ICA and ECA averaged 56 +/- 16 and 53 +/- 12 mm Hg, respectively. The ICA systolic stump pressure was lower than the ECA systolic stump pressure in six patients (21%), and all of these patients had persistent antegrade systolic duplex blood flow by duplex interrogation during CCA occlusion. The ICA systolic stump pressure exceeded the ECA systolic stump pressure in 19 patients (66%), and all of these patients had retrograde ICA flow during systole. Diastolic flow was also well correlated with the magnitude of the ICA/ECA stump pressure differential, with antegrade diastolic ICA blood flow in all nine patients with an ICA diastolic stump pressure less than the ECA diastolic stump pressure. None of the 10 patients with ICA diastolic stump pressure greater than ICA diastolic stump pressure maintained antegrade ICA diastolic flow, but four of these patients had flow to zero in diastole. Overall, 13 of 29 patients (45%) could be surmised to be at risk for distal embolization to the brain based on the persistence of some element of either systolic or diastolic antegrade ICA flow during common carotid occlusion. CONCLUSIONS: Common carotid occlusion alone appears insufficient to protect against distal embolization during manipulations of the carotid bifurcation. Persistent systolic or diastolic antegrade blood flow occurs in a high proportion of patients, lending credence to the use of additional protective strategies to ameliorate the risk of embolic complications.     

Duplex criteria for determining ≥50% and ≥80% internal carotid artery stenosis following carotid endarterectomy with patch angioplasty

The purpose of this study was to determine optimal velocities for detecting ≥50% and ≥80% restenosis prior to considering carotid intervention/carotid artery stenting (CAS) after carotid endarterectomy (CEA) with patching in symptomatic and asymptomatic patients. Two hundred CEA patients with 195 pairs of imaging (duplex ultrasound versus computed tomography angiography [CTA]/carotid arteriography) were analyzed. Peak systolic velocities (PSVs), end diastolic velocity (EDV) and internal carotid artery/common carotid artery (ICA/CCA) ratios were correlated to angiography. Receiver operator characteristic (ROC) curves determined optimal velocity criteria in detecting ≥50% and ≥80% restenosis. The mean PSVs for ≥50% and ≥80% restenosis were 248 and 404 c/s, respectively (P < 0.001). A PSV of ≥213 c/s was optimal for ≥50% restenosis with sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy (OA) of 99%, 100%, 100%, 98% and 99%, respectively. An ICA PSV of 274 c/s was optimal for ≥80% restenosis with sensitivity, specificity, PPV, NPV and OA of 100%, 91%, 99%, 100% and 99%, respectively. ROC analysis showed that PSVs were significantly better than EDVs and ICA/CCA ratios in detecting ≥50% restenosis. Standard duplex velocity criteria should be revised after CEA using patching. Specific carotid duplex velocities can be used to detect ≥50% and ≥80% restenosis after CEA with patch closure prior to carotid intervention/CAS.     

Internal carotid artery flow volume measurement and other intraoperative duplex scanning parameters as predictors of stroke after carotid endarterectomy

PURPOSE: Intraoperative duplex scanning (IDS) after carotid endarterectomy (CEA) has been shown to reliably identify major defects either by significant changes in peak systolic velocities or by B-mode imaging. To evaluate whether IDS could also predict postoperative strokes in technically flawless CEAs, we analyzed several hemodynamic parameters and correlated them with patient outcome. METHODS: From March 2000 to February 2001, 226 consecutive primary CEAs were performed in 208 patients (120 men). Of these, 153 lesions were asymptomatic. General anesthesia and synthetic carotid artery patches were used routinely. Intraluminal shunts were used when internal carotid artery (ICA) back-pressures were <50 mm Hg (35% of cases). IDS consisted of B-mode and color-flow imaging and spectral analyses of the common, external, and internal carotid arteries. Volume flows were measured three times, and the mean flow rate was used for this study. RESULTS: The first set of data was analyzed when the twenty-ninth patient had the second immediate postoperative stroke. It was noted that the two patients who had postoperative strokes had mean ICA volume flows (MICAVF) of 48 mL/min and 85 mL/min. Only two additional patients had MICAVF <100 mL/min. The remaining 25 cases had MICAVF ranging from 102 to 299 mL/min, with a mean of 165 +/- 57 mL/min (+/-SD) (P <.02). Although there was a significant correlation between MICAVF and ICA peak systolic velocity (P <.01), the latter was not found to be a significant predictor of postoperative stroke. Moreover, end-diastolic velocities, resistive index, ICA diameter, and ICA back-pressure also did not correlate with neurologic events. These findings led us to change our protocol for patients with MICAVF <100 mL/min. This included a repeat set of volume flow measurements after 15 to 20 minutes, withholding the reversal of heparin, and the liberal use of completion arteriography. Of the following 197 CEAs, 26 (13%) were found to have MICAVF <100 mL/min (range 55 to 99 mL/min; mean 79 +/- 18 mL/min). Of these, five had arteriography that documented spasm of the intracranial portion of the ICA in four and a small-diameter ICA (<2 mm) in one. Except for the five cases, the remaining 21 cases had MICAVF >100 mL/min (range 105 to 158 mL/min, mean 127 +/- 20 mL/min [+/-SD]) on repeat study. Four patients with persistent ICA low flow (70 to 99 mL/min) were treated with postoperative anticoagulation. One of the last 197 patients had a stroke caused by hyperperfusion syndrome 2 weeks after operation. Overall, six of 226 cases (2.7%) required revision on the basis of abnormal B-mode imaging results or peak systolic velocities >150 cm/s. There were two common carotid artery flaps, two ICA stenoses, one ICA flap, and one localized thrombus. All six were successfully revised and had repeat normal IDS study results, and none of these patients had a postoperative stroke. CONCLUSIONS: IDS is helpful in identifying residual lesions or defects that may contribute to postoperative neurologic deficits. MICAVF <100 mL/min are suggestive of spasm that could lead to thrombus formation and stroke, particularly in the presence of synthetic patches. We suggest that heparin reversal should not be used unless ICA flow rates are >100 mL/min. ICA spasm is short lived in most patients undergoing CEA.     

Impact of external carotid artery occlusion at declamping of the external and common carotid arteries during carotid endarterectomy on development of new postoperative ischemic cerebral lesions

Objective

The external carotid artery (ECA) is inadvertently occluded during carotid endarterectomy (CEA). The importance of ECA occlusion has been emphasized as a loss of extracranial to intracranial collaterals, a source of chronic embolization, or a site for extended thrombosis during wound closure. This study aimed to determine whether ECA occlusion that inadvertently developed during endarterectomy and that was eventually detected using blood flow measurement of the ECA after declamping of all carotid arteries is a risk factor for development of new postoperative ischemic lesions at declamping of the ECA and common carotid artery (CCA) while clamping the internal carotid artery (ICA). This study also aimed to determine whether intraoperative transcranial Doppler (TCD) monitoring predicts the risk for development of such lesions.

The fate of unrepaired minor technical defects detected by intraoperative ultrasonography during carotid endarterectomy

This report describes the natural history of unrepaired minor technical defects detected by intraoperative B-mode ultrasonography during carotid endarterectomy. Intraoperative ultrasonography was used to assess the technical adequacy of 80 carotid endarterectomies. Sixty-two arteries were normal on intraoperative ultrasound examination, whereas the remaining 18 arteries had a total of 21 minor residual technical defects. The 21 minor defects consisted of four internal carotid artery lesions, nine common carotid artery lesions, and eight external carotid artery lesions, 19 had 1 to 3 mm intimal flaps, and two had small stenoses. Sixteen of the 19 intimal flaps resolved before the first postoperative ultrasound study. These arteries had normal examination results, which indicated that these intimal flaps had healed. The two stenoses detected intraoperatively could not be detected by postoperative carotid duplex scanning at 1 month follow-up. No statistically significant relationship was found between the presence of a minor residual defect on intraoperative ultrasonography and the subsequent development of recurrent stenosis or occlusion in any of the arteries assessed. These data suggest that certain minor technical defects in the carotid artery that were detected by intraoperative ultrasonography are benign and may not require repeat exploration of the carotid artery for repair.     

The effect of intraoperative duplex on the management of postoperative stroke

BACKGROUND: Stroke after carotid endarterectomy (CEA) may be a result of intraoperative ischemia, embolism, or thrombosis at the operative site. Intraoperative duplex should eliminate the occurrence of a severe internal carotid artery (ICA) thrombosis and, thus, negate the benefit of reoperation. This article will detail the results of our evolving treatment algorithm for immediate versus delayed post-CEA neurologic deficit (ND). METHODS: We studied patients who had an ND after CEA from 1988 to 2000. Results. Thirty-two patients (3.2%) had a post-CEA ND (26 related stroke or transient ischemic attack, 6 other); 31 had a satisfactory intraoperative duplex post-CEA, 1 was not tested. Fifteen patients awoke from operation with a related deficit, 5 of whom were re-explored and all had a patent ICA. One patient without lateralizing signs who was not re-explored had extensive thrombosis at postmortem. The remaining 9 all had a duplex-proven patent ICA. Ten patients had a lucid interval before their related ND. Six patients were re-explored and all had thrombosed ICAs; 5 of the 6 improved postthrombectomy. Four patients were not re-explored for various reasons; a carotid thrombosis was not later diagnosed in any of these patients. CONCLUSIONS: Intraoperative and postoperative duplex has modified our treatment of post-CEA stroke. No longer are all patients re-explored. Patients with a normal intraoperative duplex who awaken with an immediate stroke do not usually have occlusive thrombus and routine re-exploration does not benefit these patients. Patients who have an ND develop after a lucid period may have a thrombosed ICA despite a normal intraoperative duplex, and unless there is a timely normal duplex, re-exploration is recommended and appears to benefit these patients.     

New duplex ultrasound scan criteria for managing symptomatic 50% or greater carotid stenosis

PURPOSE: The North American Symptomatic Carotid Endarterectomy Trial (NASCET) showed that selected patients benefited from surgery when their carotid artery was 50% or more stenosed. This study assessed the accuracy of color-flow duplex ultrasound scanning (DUS) parameters to detect 50% or greater carotid artery stenosis and to determine the situations in which carotid endarterectomy (CEA) without angiography could be justified. METHODS: From March 1, 1995, to December 1, 1995, all patients considered for CEA were studied with DUS and carotid angiography. Results of the two tests were blindly compared. DUS measurements of internal carotid artery (ICA) peak systolic velocity (PSV), end diastolic velocity, and ratio of the ICA to common carotid artery PSV (ICA/CCA) were subjected to receiver operator characteristic curve analysis to determine the most accurate criterion predicting 50% or greater angiographic stenosis. The criterion for identifying patients for CEA without angiography was selected from criteria with a high positive predictive value (PPV) and sensitivity. RESULTS: A total of 188 carotid bifurcations were available for comparison. A PSV (ICA/CCA) of 2 or higher was the most accurate criterion for detection of 50% or greater stenosis, with an accuracy rate of 93% (sensitivity, 96%; specificity, 89%; PPV, 92%). A PSV (ICA/CCA) of 3.6 or higher was the best criterion for identifying candidates for CEA who had not undergone earlier angiography, with PPV, sensitivity, specificity, and accuracy rates of 98%, 77%, 98%, and 86%, respectively. CONCLUSION: These redefined criteria detect the NASCET-defined threshold level of 50% or greater ICA stenosis, above which CEA results in stroke reduction. A management algorithm based on these criteria should help to minimize both angiography and unnecessary intervention.     

Outcome in Patients with Symptomatic Occlusion of the InternalCarotid Artery

OBJECTIVES: to assess whether the risk of recurrent ischaemic stroke in patients with symptomatic internal carotid artery (ICA) occlusion has changed over the past decades, to determine risk factors for the occurrence of ischaemic stroke and to assess the risk of endarterectomy (CEA) of a severe contralateral ICA stenosis. DESIGN: retrospective cohort study. PATIENTS AND METHODS: patients with symptomatic ICA occlusion were identified from duplex registry files between 1991 and 1995. Information was obtained on vascular risk factors, performance of CEA for a contralateral ICA stenosis and on recurrence of ischaemic stroke. The rate of complications occurring within 30 days after CEA of the contralateral ICA in patients with symptomatic ICA occlusion was compared with the risk of CEA in patients with asymptomatic ICA occlusion and severe contralateral ICA stenosis (symptomatic or asymptomatic). RESULTS: ninety-seven patients were identified. Mean follow-up time was 26 months. The annual risk of (non-)fatal stroke was 5.3% for all strokes (95% CI 2. 9%-9.6%) and 3.8% for ipsilateral stroke (95% CI 1.9%-7.7%). Hyperlipidaemia and severe stenosis of the contralateral ICA were independent risk factors. Twenty-two of 32 patients with a severe stenosis of the contralateral ICA underwent CEA, of which one patient died and three suffered a minor ischaemic stroke. The perioperative risk of CEA in the control group of 20 patients with asymptomatic contralateral ICA occlusion was 0% (0 of 20). CONCLUSIONS: outcome in patients with symptomatic ICA occlusion has not substantially improved over the years. CEA for severe stenosis of the contralateral ICA carried a relatively high risk in our series, but deserves to be studied in a controlled design.     

Long-term impact of the Vascular Study Group of New England carotid patch quality initiative

ObjectivePatch angioplasty has been shown to decrease rates of restenosis after carotid endarterectomy (CEA). In 2003, the Vascular Study Group of New England (VSGNE) implemented its first quality initiative aimed at increasing the rates of patch closure after CEA. This study reports the effects of that initiative on the rate of patch closure in the VSGNE and also postoperative and 1-year CEA outcomes.MethodsPatients undergoing CEA (N = 14,636) within the VSGNE between 2003 and 2014 were studied. Rates of in-hospital postoperative events (death, ipsilateral stroke or transient ischemic attack [TIA], and return to the operating room for bleeding) and events during 1 year of follow-up (stroke or TIA and restenosis >70% or occlusion) were compared by repair type—patch closure, primary closure, or eversion. One-year follow-up events were also compared over time and by annualized surgeon volume.ResultsDuring the 12 years studied, patch use increased from 71% to 91% (P < .001). There was no difference in postoperative death or ipsilateral stroke or TIA between the repair types. However, there was a statistically lower rate of return to the operating room for bleeding (P < .001), 1-year stroke or TIA (P < .003), and 1-year restenosis or occlusion (P < .001) with patch closure. Overall, the rates of 1-year stroke or TIA and restenosis decreased over time in the VSGNE. The initiative affected patch closure rates and outcomes of high-volume surgeons (>47 CEAs/y) the most. High-volume surgeons increased patch use from 50% to 90% and decreased their restenosis rates from 9.0% to 1.2% and 1-year stroke or TIA from 4.9% to 1.9% (P < .001).ConclusionsThe VSGNE carotid patch quality initiative successfully increased the rates of CEA patch closure. During the same time, there has been a decrease in postoperative bleeding requiring reoperation and 1-year ipsilateral neurologic events and restenosis or occlusion.     

Duplex ultrasound velocity criteria for the stented carotid artery

OBJECTIVES: Ultrasound velocity criteria for the diagnosis of in-stent restenosis in patients undergoing carotid artery stenting (CAS) are not well established. In the present study, we test whether ultrasound velocity measurements correlate with increasing degrees of in-stent restenosis in patients undergoing CAS and develop customized velocity criteria to identify residual stenosis > or =20%, in-stent restenosis > or =50%, and high-grade in-stent restenosis > or =80%. METHODS: Carotid angiograms performed at the completion of CAS were compared with duplex ultrasound (DUS) imaging performed immediately after the procedure. Patients were followed up with annual DUS imaging and underwent both ultrasound scans and computed tomography angiography (CTA) at their most recent follow-up visit. Patients with suspected high-grade in-stent restenosis on DUS imaging underwent diagnostic carotid angiograms. DUS findings were therefore available for comparison with luminal stenosis measured by carotid angiograms or CTA in all these patients. The DUS protocol included peak-systolic (PSV) and end-diastolic velocity (EDV) measurements in the native common carotid artery (CCA), proximal stent, mid stent, distal stent, and distal internal carotid artery (ICA). RESULTS: Of 255 CAS procedures that were reviewed, 39 had contralateral ICA stenosis and were excluded from the study. During a mean follow-up of 4.6 years (range, 1 to 10 years), 23 patients died and 64 were lost. Available for analysis were 189 pairs of ultrasound and procedural carotid angiogram measurements; 99 pairs of ultrasound and CTA measurements during routine follow-up; and 29 pairs of ultrasound and carotid angiograms measurements during follow-up for suspected high-grade in-stent restenosis > or =80% (n = 310 pairs of observations, ultrasound vs carotid angiograms/CTA). The accuracy of CTA vs carotid angiograms was confirmed (r(2) = 0.88) in a subset of 19 patients. Post-CAS PSV (r(2) = .85) and ICA/CCA ratios (r(2) = 0.76) correlated most with the degree of stenosis. Receiver operating characteristic analysis demonstrated the following optimal threshold criteria: residual stenosis > or =20% (PSV >or =150 cm/s and ICA/CCA ratio > or =2.15), in-stent restenosis > or =50% (PSV > or =220 cm/s and ICA/CCA ratio > or =2.7), and in-stent restenosis > or =80% (PSV 340 cm/s and ICA/CCA ratio > or =4.15). CONCLUSIONS: Progressively increasing PSV and ICA/CCA ratios correlate with evolving restenosis within the stented carotid artery. Ultrasound velocity criteria developed for native arteries overestimate the degree of in-stent restenosis encountered. These changes persist during long-term follow-up and across all grades of in-stent restenosis after CAS. The proposed new velocity criteria accurately define residual stenosis >or =20%, in-stent restenosis >or =50%, and high-grade in-stent restenosis > or =80% in the stented carotid artery.     

Correlation of postoperative and two-year follow-up angiography with neurological function in 99 carotid endarterectomies in 86 consecutive patients.

Eighty-six consecutive patients in 1982 underwent 99 endarterectomies and routine postoperative digital subtraction angiography. Ten vessels were closed primarily and 89 with a patch graft. Minor morbidity was 2%, major morbidity 0%, and mortality 1%, but these varied according to the patient's preoperative medical and neurological function and angiographic findings. Postoperative patency for the common carotid artery (CCA) and internal carotid artery (ICA) was 100% and for the external carotid artery (ECA) 97%. Seventy-nine vessels were evaluated by a DSA 2 years after surgery. There was one asymptomatic occlusion in follow-up and one symptomatic re-stenosis in a patient with a proven heparin induced hypercoagulability state. The three postoperative ECA occlusions were associated with a lethal postoperative stroke, the only ICA occlusion in follow-up, and a 50% stenosis of the CCA in follow-up at the site of ECA occlusion. Vein patch grafting protected the ICA but not the CCA from recurrent stenosis. The carotid slim sign on preoperative angiograms is judged to indicate a patient at high risk of stroke morbidity.     

B-mode ultrasound measurement of carotid bifurcation stenoses: is it reliable?

In the majority of cases, duplex ultrasonography (DU) is the sole imaging study necessary before carotid interventions. Duplex-derived internal carotid artery (ICA) peak systolic velocity (PSV), ICA end-diastolic velocity (EDV) and ICA/common carotid artery (CCA) PSV ratio are the most commonly utilized parameters for predicting critical carotid stenoses. However, the role of direct B-mode image measurement of maximal ICA narrowing is ill defined. The images and records of 192 patients who underwent both arteriography and duplex ultrasonography (DU) of 375 carotid arteries from January 1995 to November 2000 were reviewed. All DUs were performed by registered vascular technologists (n=6). Maximum arteriographic stenosis was determined according to the NASCET study design. With arteriography as the "gold standard," B-mode image (BMI) measurement of the maximal ICA luminal narrowing relative to the carotid bulb (n=162)as well as the peak systolic velocity in the internal carotid artery (PSVICA) (n=330), end-diastolic velocity in the internal carotid artery (EDV(ICA)) (n=198), and the ratio of the PSVs in both the ICA and the CCA (PSVICA/CCA) ratio (n=319) were subjected to receiver operator characteristics (ROC) curves for 3 clinically relevant stenoses thresholds: 50-99%, 60-99%, and 70-99%. A strong correlation was found between B-mode image (BMI)and the NASCET arteriographic measures of carotid stenosis (r =0.80;p<0.001) and was similar among the 6 technologists (r =0.74-0.89;p>0.2). The overall accuracy of BMI measurement to diagnose 50%, 60%,and 70% arteriographic carotid stenosis was 85.3%, 82.2%, and 87%, respectively. BMI measurement was similar to the most accurate PSV(ICA), EDV(ICA), and PSV(ICA/CCA) ratio at all 3 threshold stenoses levels (p>0.3). When combined with the velocity criteria, BMI measurement improved the positive predictive value (PPV) for all arteriographic stenoses thresholds by an average of 12.6% for PSV(ICA), 21.2% for EDV(ICA), and 14.2% for PSV(ICA/CCA) ratio. BMI measurement of carotid bifurcation narrowing is as reliable as duplex-derived velocity criteria in evaluating clinically relevant threshold ICA stenoses. The routine use of B-mode ultrasound in conjunction with the velocity parameters enhances the PPV of carotid DU. Our experience suggests that with current refinements in B-mode resolution, BMI stenosis measurements are accurate among experienced technologists and are a useful adjunct to duplex-derived velocity parameters.     

颅外段颈动脉狭窄的治疗策略

目的：探讨颅外段颈动脉粥样硬化性狭窄的治疗方法。方法回顾性分析上海中山医院血管外科2012年1～6月51例颅外段颈动脉粥样硬化性狭窄患者的临床资料,16例行颈动脉内膜剥脱术（carotid endarterectomy,CEA）,35例行颈动脉支架置入术（ carotid artery stenting ,CAS）。结果51例手术均获成功,1例CAS术后即刻脑卒中,1例CEA术后第3天短暂性脑缺血发作（transient ischemic attack,TIA）,1例CAS术后颈动脉窦压迫。全组术后随访9～15个月,平均13．6月,复查颈动脉B超,无严重再狭窄。结论根据颅外段颈动脉粥样硬化性狭窄患者的相关医学资料,对于有下列情况之一的患者我们倾向于行CEA：①6个月内1次或多次TIA,且颈动脉狭窄度≥70％;②6个月内1次或多次轻度非致残性卒中发作,症状或体征持续超过24小时且颈动脉狭窄度≥70％;③对于经颈部血管CTA和颈动脉全脑血管造影发现的颈动脉狭窄段≥2 cm。对于有下列情况之一的患者我们倾向于行CAS：①无症状性颈动脉狭窄度≥70％;②有症状性狭窄度范围50％～69％;③无症状性颈动脉狭窄度＜70％,但血管造影或其他检查提示狭窄病变处于不稳定状态。     

Effect of urgent carotid endarterectomy on operative risk and benefit

Objectives:The time of Carotid intervention for recently symptomatic,severe carotid stenosis which cause a transient ischemic attack or minor stroke is still a controversial issue.Early studies showed that carotid endarterectomy (CEA) caused a high risk if performed within days follow an acute ischemic stroke.However,The National Stroke Strategy posted by UK Department of Health advocated that this situation should be regarded as an emergency procedure,and carotid intervention should ideally be performed within 48 hours.We designed this study to discuss the effect of urgent CEA on operative risk and benefit.Methods: we analyze 12 urgent CEA with primary closure performed during 1996 to 1998.All 12 patients were underwent CEA within 2 weeks,and 2 of them within 2 days.Operative risks and overall benefit from surgery were discussed in relation to the time from the last symptomatic event to CEA.Results: 2 urgent CEA performed in 2 days are recovery uneventful.1 of 12 patients,who underwent urgent CEA within 2 weeks,occurred restenosis after 3 months follow up.No 30-day perioperative recurrent TIA,stroke and death.Conclusions:CEA performed within 2 weeks is feasible and reliable procedure in preventing recurrent TIA and stroke after presenting manifestations.The future aim is to perform CEA within 48 hours after TIA or stroke symptoms.     

A rational algorithm for duplex scan surveillance after carotid endarterectomy.

PURPOSE: This study was undertaken to determine the appropriate timing and frequency of duplex ultrasound scanning after carotid endarterectomy (CEA) for the detection of high-grade stenosis caused by recurrent carotid stenosis or contralateral atherosclerotic disease progression. METHODS: In 221 patients who underwent 242 CEAs, duplex scanning was performed before, during, and after operation (in 3-month to 6-month intervals). High-grade internal carotid artery (ICA) stenosis (peak systolic velocity, >300 cm/s; diastolic velocity, >125 cm/s; ICA/common carotid artery ratio, >4) prompted the recommendation for repair. An average of four postoperative scanning procedures was performed during a mean follow-up period of 27.4 months. RESULTS: Intraoperative duplex scan results prompted the immediate revision of 12 repairs (4.9%), and one perioperative stroke (<1%) occurred. Six CEAs (2.7%) had asymptomatic recurrent stenosis (>50% diameter-reduction [DR]; systolic velocity, >125 cm/s) develop. Only one of six patients had >75% DR stenosis develop and underwent reoperation (<1% yield for CEA surveillance). The yield of surveillance of the unoperated ICA was higher (P =.003), and 12% of unoperated sides had progressive stenosis (n = 21) or occlusion (n = 3) develop, which led to seven CEAs for high-grade stenosis. Disease progression to >75% DR stenosis was five times as frequent (P =.002) in patients with >50% DR stenosis initially. All patients but one who required contralateral endarterectomy for disease progression had >50% ICA stenosis when first seen. During the follow-up period, no disabling strokes ipsilateral to an operated carotid artery occurred, but three strokes occurred in the hemisphere of the contralateral unoperated ICA. CONCLUSION: The yield of duplex scan surveillance after CEA was low. Only 13 patients (5.9%) had severe disease develop to warrant additional intervention. Progression of contralateral disease rather than restenosis was the most common abnormality that was identified. Duplex scanning at 1-year to 2-year intervals after CEA is adequate when a technically precise repair is achieved and minimal contralateral disease (<50% DR) is present. A policy of duplex scan surveillance and reoperation for high-grade stenosis was associated with a 1.6% incidence rate of disabling stroke during the follow-up period.