Color Duplex Ultrasound Scanning Research Articles

EFFICACY OF DISTAL REVASCULARIZATION IN PATIENTS WITH CRITICAL LIMB ISCHEMIA

Critical limb ischemia (CLI) leads to an increase in the above-the-knee amputations and mortality, which can reach 40 %.
 The aim of the study is to improve the results of treatment in patients with CLI by including endovasal revascularization methods in complex therapy.
 Materials and Methods. The results of surgeries on lower limb arteries in 189 patients were analyzed; among them 110 patients were diagnosed with CLI. The study enrolled 74 men (67.3 %), and 36 women (32.7 %). The average age was 68 years old. Patients underwent color duplex ultrasound scanning (CDUS) and CT angiography. Along with surgical revascularization, patients were prescribed antibacterial, anticoagulant, antiplatelet and insulin therapy (those with diabetes mellitus).
 Results. 110 patients with CLI underwent endovascular revascularization: balloon angioplasty – 110 (100 %), stenting – 54 (49.1 %), hybrid surgeries – 9 (8.2 %), atherectomy and mechanical aspiration – 9 (8.2 %). 88 patients with CLI (80 %) were also diagnosed with multilevel lower extremity arterial disease, and only 22 patients (20 %) had segmental lesions. Above-the-knee amputation was performed in 4 patients, below-the-knee amputation was conducted in 2 patients. Out of 110 patients, 7 people died (6 %). Out of 103 patients, 97 people (94 %) preserved foot balancing function.
 Conclusion. In patients with CLI and distal arterial bed, endovascular revascularization prevented above-the-knee amputation in 94%. Thus, it allowed us to maintain foot balancing function in patients.

Clinical case of a patient with occlusive thrombosis of the right common carotid artery

The paper presents a case of a patient with floating thrombosis in the right common carotid artery and occlusion of the carotid bifurcation of the right common carotid artery against the background of severe atherosclerosis of the common carotid artery with 70% stenosis. Thrombosis was identified using color duplex ultrasound scanning in an asymptomatic patient. During hospitalization, thrombosis was complicated by a cerebral infarction of the right middle cerebral artery, apparently of embolic origin.

Outcome of percutaneous transluminal angioplasty for subacute lower limb ischemia

Context Management of acute limb ischemia ( Aim The aim of this study was to evaluate the clinical and hemodynamic outcome of percutaneous transluminal angioplasty for subacute lower limb ischemia. Settings and design A total of 22 limbs that presented with subacute leg ischemia admitted to Alexandria Main University Hospital have been studied prospectively. All patients had femoro-popliteal occlusions shown by multislice computed tomographic angiography and severe leg ischemic pain +/− crippling claudication. Patients with acute leg ischemia or extensive foot necrosis necessitating amputation were excluded from the study. Patients and methods All patients were subjected to ankle-brachial index (ABI) measurement, color duplex ultrasound (CDU) scan, and multislice computed tomographic angiography before intervention. Percutaneous transluminal angioplasty (balloon angioplasty +/− stent deployment) was performed for all participants. Clinical follow-up with ABI measurement was done at 1-, 3-, and 6-month intervals. CDU after 6 months for patency and restenosis was performed. Statistical analysis Statistical Package for the Social Sciences, version 15.0 was used. Values were compared with a paired samples t test. P values less than 0.05 were considered significant. Results Mean follow-up period was 6.2 months. The mean (±SD) ABI before and at 1-, 3-, and 6-month interval was 0.4 (±0.2), 0.53 (±0.11), 0.62 (±0.12), and 0.86 (±0.16), respectively, with P value less than 0.0001. Limb salvage rate for those patients who had constant ischemic pain and had primary technical success was 89%. As for those patients who had severe claudication, at 6-month follow-up, they had no complaint. Primary patency rate by CDU was 95%. Conclusions Balloon angioplasty is a safe and effective tool for management of subacute leg ischemia. It avoids high surgical risks and carries promising patency and limb salvage rates.

Initial Experience with Percutaneous Angioplasty of the Common Femoral Artery in De Novo Stenotic Lesions

The aim of this study was to report an initial experience with percutaneous transluminal angioplasty (PTA) in de novo stenotic lesions of the common femoral artery (CFA). A retrospective analysis for 34 consecutive patients was conducted. The follow-up consisted of clinical evaluation and color duplex ultrasound scan (CDU) 1, 6, and 12 months after the procedure. The symptoms were claudication in 16 patients (47%), critical limb ischemia in 17 (50%), and preservation of an infrainguinal bypass in 1 (3%). PTA was performed in CFA alone in 45.7%, associated to iliac and/or profunda/superficial femoral artery PTA in 54.3%. Stenting was performed in 23 patients (65.7%). All procedures were successful. Two patients required surgery for a local complication. Median hospital stay was 2 days. Mean follow-up was 11 months (range 1-56). Primary and secondary sustained clinical improvement rates were 77% and 85%, and primary, CDU-controlled patency rate was 88%. Four reinterventions were required for symptomatic CFA restenosis. At the end of follow-up, no major amputation had been performed, all patients with claudication remained improved with no restenosis, and the secondary sustained improvement rate was 85%. PTA for primary CFA lesions is feasible and safe, with acceptable short-term results in claudicants. In patients with tissue loss, frequent reinterventions raise questions about PTA benefit. This approach needs to be compared with open surgery in a randomized trial.

Change in the lower limb deep venous flow in peripheral atherosclerotic arterial disease.

AimThis prospective study was undertaken to determine how peripheral atherosclerotic disease influences the flow in the deep veins of the leg.Material and methodThirty one subjects with peripheral atherosclerotic disease and 23 age matched control subjects were studied. The popliteal vein flow velocity was measured at rest and during reactive hyperemia by means of color duplex ultrasound scanning. Patient age, ankle-brachial index (ABI) and the presence of risk factors for venous thrombosis were also recorded.ResultsThere was a negative correlation between the ankle-brachial index and venous flow velocity among subjects with peripheral arterial disease (p=0.001). There was a negative correlation between dyslipidemia and resting venous flow velocity (p=0.049). During reactive hyperemia, venous flow velocity increased less in subjects with peripheral arterial disease than it did in control subjects (p=0.007). The subjects with dyslipidemia showed no changes in venous flow velocity in reactive hyperemia measurements (p=0.908).ConclusionIncreasing the venous flow velocity in peripheral arterial disease, may confer some protection against the deep venous thrombosis.

Statins Promote Residual Aneurysm Sac Regression Following Endovascular Aortic Aneurysm Repair

Regression of the residual sac is indicative of successful endovascular aortic aneurysm (EVAR) repair. Using color duplex ultrasound (CDU), we monitored the residual aneurysm sac following EVAR and correlated sac behavior with perioperative risk factors. Of 145 patients with EVAR, 106 (73.1%) patients between January 01, 2003, and July 01, 2010, had at least 2 consecutive postoperative scans and thus were eligible for inclusion. Mean (± standard deviation [SD]) CDU scans per person was 4.6 (± 1.4). All were conducted by the same technologist using a standard protocol on the same machine. Aneurysm sac change in centimeters and percentage terms was calculated. The presence or absence of an endoleak was also recorded. Change in aneurysm sac size was correlated with preoperative risk factors. Mean sac size change at 1 month was a decrease of 0.24 cm, equating to a percentage change of 4.3%. At 7 months, the decrease was 0.59 cm (9.8%), at 12 months, 0.73 cm (12.4%), at 18 months 0.92 cm (15.8%), and at 36 months 1.0 cm (16.6%). Both univariate and multivariate analyses demonstrated that statin therapy (P = .002) was the only risk factor variable positively associated with aneurysm regression while the presence of an endoleak was inversely related to sac reduction (P = .01). Maximum aneurysmal sac reduction seems to occur in the first year following endograft implantation. Statin therapy appears to be associated with an increased likelihood of sac regression following EVAR. Further investigation of the role of statins in the biology of abdominal aortic aneurysmal disease is warranted.

Guidelines for the treatment of venous ulcers

1. Co-chaired this panel2. University of South Florida, Tampa, FL3. Healthpoint Ltd., Fort Worth, TX4. University of California, San Francisco, CA5. University of Texas Medical Branch, Galveston, TX6. University of Cardiff, Cardiff, Wales, UK7. University of Pennsylvania, Philadelphia, PA8. Private practice, Warren, PA9. Private practice, Tamarac, FL10. University of Pittsburgh, Pittsburgh, PA11. St. Louis University, St. Louis, MO, and12. Washington University, St. Louis, MO

Hemodynamic and morphologic evaluation of sequelae of primary upper extremity deep venous thromboses treated with anticoagulation

This study was performed to describe venous function, residual morphologic abnormalities, and the occurrence of post-thrombotic syndrome in patients with conservatively treated primary upper-extremity deep venous thromboses (UEDVT). This was a retrospective follow-up study of 31 patients with previous primary UEDVT treated with anticoagulation only, identified by a search of medical records. The mean follow-up time was 5 years. The patients were evaluated by interview, clinical examination, computerized strain-gauge plethysmography, and color duplex ultrasound imaging. The grade of post-thrombotic syndrome was rated according to the Villalta score (0 to 3 on each of four subjective and five clinically assessed features). The rate of venous emptying was significantly lower in the arms with DVTs than in the contralateral arms (P < .001). Eleven of the patients (35%) had a remaining outflow obstruction in the affected arm (venous emptying <68 mL/100 mL per min). Eighteen (58%) had a residual thrombus according to color duplex ultrasound scans, with four remaining occluded subclavian veins. None of the patients had deep or superficial venous reflux. There was no statistically significant relationship between plethysmographic and duplex findings. Most (77%) of the patients reported remaining symptoms in the affected arm, and there was a significant side difference in upper arm circumference (P < .001). Approximately one third had developed a moderate grade of post-thrombotic syndrome according to the Villalta score (total, 5 to 9). No significant relation was evident between the post-thrombotic syndrome score and duplex findings. Patients with post-thrombotic syndrome had a lower venous emptying value than those without (69 vs 84 mL/100 mL per min), but this difference was not statistically significant. Patients with conservatively treated previous primary UEDVT had significantly reduced venous outflow capacity and a residual thrombus was common. Swelling of the arm was the most common symptom, and one third had a moderate grade of post-thrombotic syndrome. However, there was no clear relation between hemodynamic and morphologic factors and the development of post-thrombotic syndrome in these 31 patients, examined at a mean of 5 years after an acute DVT episode.

Use of short PTFE segments (

The re-establishment of patency in a stenosed or thrombosed native arteriovenous fistula (AVF) is fundamental to regaining adequate hemodialysis through the same cannulable vein. Many surgeons have been reluctant to use even small segments of synthetic grafts in AVF revisions because of a perception that these would lead to poor results; however, studies comparing various treatment options are scarce. This study compared the use of short (<6 cm) polytetrafluoroethylene (PTFE) segments with pure autologous repair in stenosed or thrombosed native fistulas. The cumulative postintervention primary patency rates of two groups of hemodialysis patients receiving different surgical revision operations of their vascular accesses were prospectively compared. Group I (n = 30) comprised patients who presented with stenosed or thrombosed native fistulas and received short (2 to 6 cm) interposition PTFE grafts placed after the stenosed or thrombosed outflow vein segment was resected. These short PTFE grafts were not used for cannulation. Group II (n = 29) comprised patients who presented with dysfunctional or failed AVFs and underwent various types of pure autogenous corrections. AVF dysfunction or thrombosis was detected with clinical examination and color duplex ultrasound scanning. In all cases, on-table arteriography-fistulography was performed before surgical repair. Access adequacy was assessed in all patients postoperatively after the first puncture and every month thereafter (mean follow up 16.7 months). No statistically significant difference in patency was observed between the two groups. Postintervention cumulative patencies were 100%, 88%, and 82% for group I and 90%, 82%, and 71% for group II at 6, 12, and 18 months, respectively ( P = .8). Short (<6 cm) interposition PTFE segments used for the revision of failing or failed AVFs compare favorably to purely native repair and do not alter the autologous behavior of the initial access. These short PTFE revisions resulted in satisfactory midterm primary patency without further consumption of the venous capital by harvesting segments of vein from other locations and without compromising more proximal access sites. This practice is recommended and is justified as part of an aggressive access salvage policy addressed by many authors so far.

The utility of color duplex ultrasonography in the diagnosis of temporal arteritis.

Temporal arteritis (TA) is frequently diagnosed with nonspecific clinical characteristics, followed by a temporal artery biopsy to confirm the presence of vasculitis. Consequently, numerous screening surgical biopsies are performed with a high negative-biopsy rate. A prospective study was performed evaluating color duplex ultrasound scan (CDU) as the preferred method for the diagnosis of vasculitis in the evaluation of suspected TA. Thirty-two patients with suspected TA on the basis of clinical criteria were evaluated with CDU before a temporal artery biopsy. The presence of a hypoechoic "halo," suggesting edema of the inflamed vessel, and inflammatory stenoses were noted. Histologic examinations of standard temporal artery biopsies then were performed, and the results were compared with the CDU findings. In addition, a metaanalysis was performed to identify articles related to the use of ultrasound scan in the detection of TA. All patients completed a bilateral CDU examination of the temporal arteries, and in 75% of patients biopsied, no evidence of vasculitis was found at histologic examination. When CDU examined for halo alone as the determinant for disease, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), compared with histologic confirmation of TA, were 85.7%, 92.0%, 75.0%, and 95.8%, respectively. With the criteria for a halo sign present, an inflammatory stenosis present, or both present on CDU, the sensitivity, specificity, positive predictive value, and NPV were 100%, 80.0%, 58.3%, and 100%, respectively. CDU is a superior noninvasive method of determining the presence of vasculitis when compared with routine surgical biopsy. Examination of the temporal artery with CDU can effectively predict which patient will need surgical biopsy. The utility of CDU in the diagnosis of TA is maintained by a high sensitivity in detecting patients with the disease and also by a high NPV that can eliminate patients who would not benefit from biopsy.

Endograft limb occlusion and stenosis after ANCURE endovascular abdominal aneurysm repair

Objective: The purpose of this study was to define the incidence and treatment of endograft limb stenosis or occlusion (endograft limb dysfunction [ELD]) in a single center with the ANCURE unsupported bifurcated or aortouniiliac endograft by using intraoperative completion angiography and postoperative color duplex ultrasound scanning (CDU). Methods: Sixty-seven endografts (58 bifurcated, 9 uniiliac) were implanted between February 1996 and July 2000. Intraoperative completion aortography was performed in every patient. Postoperative assessment of the endograft consisted of CDU and computed tomography scanning and kidney, ureter and bladder radiographs within 7 days of implantation, at 3 and 6 months after the operation, and every 6 months thereafter. Results: At the time of endograft implantation, widely patent normal-appearing endograft limbs were revealed by means of the initial completion angiogram in 58 of 67 patients (group 1). ELD subsequently developed in seven of these 58 patients (13.4%). The results of the completion angiogram were not normal in the remaining nine patients (group 2), leading to the deployment of a self-expanding stent within the endograft limbs. The results of subsequent angiography were normal. No ELD has occurred in any patient in group 2 to date. The primary assisted patency rate at 30 months was 88% ± 5.2% for group 1 versus 100% ± 0% for group 2 (P = not significant, Log-rank test). Postoperative ELD occurred in seven patients (10.4%). Endovascular graft thrombosis occurred in three patients (3 endograft limbs). In each case, an endovascular approach was attempted; however, the guidewire would not traverse the occluded endovascular graft limb. Revascularization was accomplished by means of femorofemoral bypass grafting. Endovascular graft stenosis occurred in four patients (4 endograft limbs). Three patients with bifurcated endografts and limb stenosis who had no symptoms diagnosed by means of CDU were successfully treated by means of balloon angioplasty with self-expanding stent implantation, and the endograft limbs remained patent at 3, 5, and 26 months follow-up. The remaining patient who had an aortouniiliac endograft with recurrent severe stenoses underwent endograft explantation and aortobifemoral bypass grafting. The overall incidence of ELD during or after endovascular abdominal aortic aneurysm repair was 23.8% (16 of 67 patients). Conclusion: Unsupported endografts are at risk for developing ELD. The use of stents for limb support at the time of the initial endograft implantation may prevent subsequent ELD and bears further study. Endograft limb occlusion usually presents with acute severe ischemic symptoms, and the failure of operative thrombectomy necessitates femorofemoral artery bypass grafting. Endograft limb stenosis is identified by means of CDU surveillance in the postoperative period. Prompt treatment with percutaneous transluminal angioplasty/stent yields satisfactory primary assisted patency. Intraoperative intravenous ultrasound scanning, oblique angiograms, pressure gradients, and completion angiography may be necessary to detect and treat ELD. (J Vasc Surg 2002;35:686-90.)

The incidence and natural history of type I and II endoleak: A 5-year follow-up assessment with 1 color duplex ultrasound scan

The purpose of this study was the demonstration of the value of color duplex ultrasound (CDU) scanning in the detection of type I endoleak (T1EL) and type II endoleak (T2EL), the correlation of Doppler scan waveform pattern to endoleak persistence or seal, and the description of the natural history of endoleak. The study was a retrospective review of 83 patients who underwent periodic CDU scan and computed tomographic (CT) scan surveillance of the endograft and aneurysm sac after insertion of an aortic endograft for abdominal aortic aneurysm (AAA). Forty-one patients (49%) with an endoleak at anytime in the follow-up period form the basis of this report. T1EL was detected in all five patients with CDU and CT scans. T2EL was detected in 36 patients with CDU scan as compared with 18 patients with CT scan. With CT scan, endoleak was not detected when CDU scan showed no endoleak. Conversely, all CT scan--detected endoleaks were found with CDU scanning. The T2EL source artery was identified with CT scan in seven patients, whereas the source was identified in all 36 patients with CDU scan. Endoleak source did not correlate with outcome (seal or persistence). However, a to/fro Doppler scan waveform pattern was associated with spontaneous T2EL seal in seven of 12 patients, and a monophasic or biphasic waveform was associated with endoleak persistence in 14 of 17 patients (P =.023, with chi(2) test). Thirteen of 36 T2ELs underwent spontaneous seal by 6.2 +/- 2.8 months. T2ELs without increasing AAA diameter were observed. Eight patients with persistent T2EL present for more than 12 months did not undergo treatment. However, two patients underwent T2EL obliteration with coils because of AAA sac enlargement. T1EL of the distal attachment site was the initial endoleak identified in five patients, but seven patients harboring T2ELs had subsequent T1ELs develop. For the entire 83 patients, the combined T1EL and T2EL prevalence rate was 20% of patients at a 6-month follow-up period, but this rate increased to 50% after 24 months. The incidence rate of newly detected endoleaks and of spontaneous sealing was 24.4% at 12 months and 12.5% in longer-term follow-up period. CDU scan is effective in the identification of the type of endoleak, the delineation of the vessel involved, and the hemodynamic information not available with any other testing method. Endoleaks have a dynamic natural history characterized by a variable onset with changing branch vessel involvement and spectral flow patterns. Periodic long-term endograft surveillance with CDU scanning is necessary for following existing endoleaks and for detecting new ones. Corroboration of these findings in larger multicenter prospective trials will be needed to determine whether CDU scan analysis of endoleaks would be predictive of long-term success in endovascular AAA repair.

Regarding: “The incidence and natural history of type I and II endoleak: A 5-year follow-up assessment with color duplex ultrasound scan”

Regarding: “The incidence and natural history of type I and II endoleak: A 5-year follow-up assessment with color duplex ultrasound scan”

Prospective randomized study of carotid endarterectomy with polytetrafluoroethylene versus collagen-impregnated Dacron (Hemashield) patching: Perioperative (30-day) results

Purpose: Several studies have reported that carotid endarterectomy (CEA) with patch angioplasty has results that are superior to primary closure. Polytetrafluoroethylene (PTFE) patching has been shown to have results comparable with autogenous vein patching; however, it requires a prolonged hemostasis time. Therefore, many surgeons are using collagen-impregnated Dacron patching (Hemashield [HP]). This study is the first prospective randomized trial comparing CEA with PTFE patching versus HP patching. Methods: Two hundred CEAs were randomized into two groups, 100 PTFE and 100 HP patching. All patients underwent immediate postoperative and 1-month postoperative color duplex ultrasound scanning studies. Demographic and clinical characteristics were similar in both groups, including the mean operative diameter of the internal carotid artery. Results: The perioperative stroke rates were 0% for PTFE, versus 7% for HP (4 major and 3 minor strokes, P =.02). The combined perioperative stroke and transient ischemic attack rates were 3% for PTFE, versus 12% for HP (P =.047). The operative mortality rate for PTFE was 0%, versus 2% for HP (P =.477). Five perioperative carotid thromboses were noted in patients undergoing HP patching, versus none in patients undergoing PTFE patching (P =.07). After 1 month of follow-up, 2% of patients in the PTFE group had a 50% or more restenosis, versus 12% of patients in the HP group (P =.013). The mean operative time for PTFE patching was 119 minutes, versus 113 minutes for HP patching (P =.081). The mean hemostasis time was significantly higher for PTFE patching than for HP patching, 14.4 versus 3.4 minutes (P <.001). Conclusion: CEA with HP patching had a higher incidence of perioperative strokes, carotid thrombosis, and 50% or more early restenosis than CEA with PTFE patching. However, the mean hemostasis time was higher for PTFE patching than for HP patching. (J Vasc Surg 2002;35:125-30.)

Endotension after endovascular aneurysm repair: The Ancure experience

Purpose: The expansion of aneurysms after endovascular repair is a consequence of persistent sac pressure, usually resulting from an endoleak. Several authors have suggested that sac expansion can occur even in the absence of endoleak, referring to this phenomenon as endotension. This study undertakes a review of the largest US endograft trial data to better define the significance of aneurysm expansion in the absence of endoleak. Methods: The core laboratory imaging database from the Ancure (Guidant) endovascular graft Phase I and Phase II trials approved by the Food and Drug Administration was reviewed with attention to aneurysm size and endoleak. Aneurysm size was measured with standardized two-dimensional computed tomography (CT) scan at the area of largest initial aneurysm diameter. Endoleak was detected with CT scans, color duplex ultrasound scans, and angiography in selected cases. Patients were evaluated at baseline, 3 months, 6 months, 12 months, and every 12 months thereafter. An endograft was classified as leaking if any endoleak was detected with any modality at any time point. Results: A total of 658 patients were entered into these protocols and the data submitted to the core laboratory. A control group of 120 conventional aortic patients and a group of 62 without baseline CT data were excluded from further analysis. Of the remaining 476 patients, 144 (60 tube, 60 bifurcated, and 24 mono-iliac) were free of endoleak at all intervals and had baseline CT measurements to allow comparison. Overall, the average size decrease in this nonleaking group was 9.9 ± 9.4 mm (range, –50.6-11.1 mm) at a mean follow-up of 23.3 months. Evaluation for overall aneurysm expansion revealed 17 patients who had an increase of 2.3 ± 2.9 mm (range, 0.3-11.1 mm) at a mean follow-up of 14.1 months. Only two patients without evidence of endoleak exhibited growth of more than 5 mm at maximum follow-up (7.6 mm at 12 months and 11.1 mm at 36 months). Additional analysis of sealed endoleaks and late endoleaks failed to demonstrate any group with expansion in the absence of detectable endoleak. Conclusions: Endotension appears to be rare in this large series of prospectively evaluated endografts. From this review, endotension seems more likely to represent missed endoleak than true aneurysm expansion in the absence of perigraft flow. (J Vasc Surg 2001;34:421-7.)

Carotid endarterectomy in diabetic patients

Objective: The purpose of the current study was to identify the possible short- and long-term effects of diabetes on the outcome of carotid endarterectomy. Methods: Medical records were reviewed for 781 carotid endarterectomies (in 734 patients) performed by the same vascular surgeon in a university medical center between January 1994 and December 1998. Patients were divided two groups: those with diabetes (n = 181 patients; 193 operations) and those without diabetes (n = 553; 588 operations). The two groups were similar with respect to mean age, male-female ratio, and contralateral lesions. The only significant differences were a higher prevalence of peripheral vascular disease and dyslipidemia in the diabetic group and a higher prevalence of hemispheric transient ischemic attacks among the nondiabetic patients. Carotid color duplex ultrasound scan had been performed in all patients, and in 56 patients from the diabetic group and 56 patients from the nondiabetic group (matched for age, sex, and contralateral lesions), the distal extension of the lesion from the carotid bifurcation had also been defined. Both of these subgroups were fully representative of their respective groups of origin. Carotid endarterectomy was performed after the induction of general anesthesia; electroencephalographic monitoring was continuous. Results: Except for the significantly higher prevalence of calcified plaques in the diabetic patients (P <.0001), the characteristics of the carotid disease in the two groups were similar. In the 56-member subgroups, 73.2% of the diabetic and 35.7% of the nondiabetic patients (P <.0001) had lesions extending more than 2 cm beyond the carotid bifurcation. Mean length of plaque beyond the bifurcation was 2.3 ± 0.09 cm for the diabetic and 1.7 ± 0.08 cm for the nondiabetic patients (P <.0001). Diabetes was the only factor significantly correlated with plaque length. In the diabetic subgroup, surgery was characterized by significantly longer carotid arteriotomies (P =.03) and clamp times (P <.003). Operative mortality was 1.5% in the diabetic group (2 myocardial infarctions + 1 stroke) and 0.5% in the nondiabetic group (1 myocardial infarction + 2 strokes; P value not significant); stroke rates were 1.5% (3 major strokes) and 0.5% (2 major strokes + 1 minor stroke), respectively (P = not significant). Long-term survival (5 years) was not significantly lower among the diabetic patients. Conclusions: Diabetes mellitus does not seem to significantly increase the surgical risk for carotid endarterectomy. The presence of more extensive plaques has no significant effect on the results of surgery. (J Vasc Surg 2001;33:148-54.)

Contrast-enhanced color duplex ultrasound scan in detection of endoleaks following aortic endografting

Contrast-enhanced color duplex ultrasound scan in detection of endoleaks following aortic endografting

The limits of endovascular aortic aneurysm repair

The limits of endovascular aortic aneurysm repair

Lower limb deep venous flow in patients with peripheral vascular disease

Purpose: A prospective controlled study was undertaken to determine how peripheral vascular disease (PVD) influences flow in the deep veins of the leg. Methods: Eighty-nine patients with peripheral vascular disease and 35 age-matched control subjects were studied. The popliteal vein diameter and flow velocity were measured at rest by means of color duplex ultrasound scanning, and these measurements were compared with the ankle-brachial pressure index. For 23 subjects, measurements were also performed during reactive hyperemia and then repeated after venous return from the foot was prevented by an ankle cuff. Results: There was a significant correlation between the ankle-brachial pressure index and the popliteal vein diameter ( r = 0.35, P < .001) but a negative correlation between the ankle-brachial pressure index and venous flow velocity among patients with PVD ( r = –0.24, P = .002). In PVD patients the diameter decreased further in reactive hyperemia, whereas it increased in control subjects ( P < .001). Preventing venous return from the foot in PVD patients led to diameter increase at rest and abolished the reduction in diameter caused by reactive hyperemia. Despite the reduction in diameter during reactive hyperemia, flow velocity increased less in patients with PVD than it did in control subjects ( P = .01). Conclusion: Chronic tissue ischemia results in constriction of the popliteal vein. This appears to be an active process related to the washout of humoral factors from ischemic tissues distally, which leads to an increase in flow velocity. The latter may confer some protection against the deep vein thrombosis that would otherwise tend to occur with low venous flow rates. (J Vasc Surg 1999;29:1065-70.)

Endoleak after aortic stent graft repair: Diagnosis by color duplex ultrasound scan versus computed tomography scan

Purpose: The purpose of this study was to compare the accuracy of a color duplex ultrasound scan (CDU) to a computerized axial tomography scan (CT) in the diagnosis of endoleaks after stent graft repair of abdominal aortic aneurysms. Methods: The Endovascular Aneurysm Clinical Trial Core Laboratory records were reviewed from 117 concurrent CDU and CT studies that were performed in 79 patients who were implanted with the Endovascular Technologies stent graft device between December 1995 and January 1997. All of the studies were interpreted by the Core Laboratory as having the presence or the absence of an endoleak or as being indeterminate because of technical factors. Of the 117 videotaped CDU studies available for re-examination, 100 were reassessed for technical adequacy on the basis of the following criteria: a satisfactory imaging of the aneurysm sac and of the stent graft with gray scale, and both color and spectral Doppler scan evaluation for endoleak outside the endograft and within the aneurysm sac. Results: Of the 117 studies, 103 CDUs (88%) and 114 CTs (97%) were recorded as having the presence or the absence of an endoleak and 14 CDUs (12%) and 3 CTs (3%) were indeterminate. For the studies that were recorded to have the presence or the absence of an endoleak, the sensitivity, the specificity, the positive and the negative predictive values, and the accuracy of CDUs as compared with CTs were 97%, 74%, 66%, 98%, and 82%, respectively. Of the 100 CDU videotaped studies available for review, the following results were seen: (1) 93 CDUs had satisfactory B-mode images, (2) 76 had satisfactory color Doppler scan images to evaluate for endoleaks, (3) 55 had color Doppler scan assessment of the entire abdominal aortic aneurysm sac for endoleak, and (4) 27 had spectral Doppler scan waveform confirmation of suspected endoleaks. Only 19 CDU studies (19%) with all 4 criteria for complete assessment of endoleak were performed. Conclusion: Although most of the CDU studies were technically suboptimal, the CDUs reliably identified endoleaks with an excellent sensitivity and a negative predictive value as compared with CT scans. (J Vasc Surg 1998;28:657-63.)