Carotid duplex with contralateral disease: the influence of vertebral artery blood flow.

The hemodynamic effect of severe contralateral internal carotid (ICA) disease may result in overestimation of ipsilateral stenosis by duplex ultrasound (DU). This study examines the role of the vertebral artery system (VAS) on duplex results in patients with severe carotid disease. A retrospective study of 110 patients who underwent carotid endarterectomy (CEA) between January 1, 1995 and January 31, 1998 was performed. All patients had a preoperative and postoperative DU within 6.5 months of each other and a preoperative magnetic resonance angiogram or conventional angiogram. Duplex categories of stenosis were mild (0-49%), moderate (50-79%), and severe (80-99%). Pre- and postoperative values for ICA peak systolic velocity (PSV), end diastolic velocity (EDV), and ICA-to-common carotid artery (CCA) ratio were recorded. Paired t-tests were used to assess significant changes within groups and independent t-tests were used to compare changes between groups. Sixty-seven patients had a normal VAS and 43 patients had an abnormal VAS. Patients with an abnormal VAS had significantly greater decreases in EDV after contralateral CEA. In the abnormal VAS group, there was a higher incidence (23.2% vs. 16.4%) of ipsilateral overestimation of stenosis by duplex and a greater incidence (20.9% vs. 10.4%) of postoperative decrease in stenosis following contralateral CEA than in the normal VAS group. Patients who underwent CEA for severe stenosis versus moderate stenosis had significant postoperative decreases in ipsilateral PSV, EDV, and ICA/CCA ratio. Severe contralateral stenosis patients with an abnormal VAS had a significant decrease in EDV compared to patients with a normal VAS. Vertebral artery blood flow contributes significantly to the "hemodynamic effect" of carotid disease identified by duplex.

Chronic lower extremity ischemia.

With a careful history and physical examination, aided by the judicious use of noninvasive tests, the diagnosis of chronic lower extremity ischemia can be readily made. The definition and pathophysiology, diagnosis, and treatment of chronic lower extremity ischemia are discussed.

Subfascial endoscopic perforator ligation: an analysis of early clinical outcomes and cost.

PURPOSE: Early results of subfascial endoscopic perforator surgery (SEPS) were examined. Data on ulcer healing, complications, and costs are presented. METHODS: Data were prospectively collected for all patients who underwent SEPS at our institution. A concurrent control group was not available because primary open perforator ligation is no longer performed at our hospital. Preoperative assessment included duplex scanning (valve closure times and perforator mapping), plethysmography, and phlebography. Completeness of therapy was assessed with postoperative duplex mapping of perforating veins. Clinical status was monitored after surgery, and actual costs, including equipment, personnel, and facilities management, are reported. RESULTS: Eighteen procedures were performed in 15 patients (mean age, 52 years; range, 42 to 65 years). Two patients underwent bilateral SEPS, and one patient underwent a second procedure on the same leg. Active ulceration (class 6) was present in 14 of 18 limbs (78%), recently healed ulcers (class 5) in two of 18 (11%), and lipodermatosclerosis with edema (class 4) in two. Deep venous insufficiency was present in 14 of 18 (78%). The number of perforating veins ligated per leg ranged from 0 to 12 (mean, 4.3). Follow-up ranged from 3 to 64 weeks (mean, 22 weeks). Complete ulcer healing occurred in eight of 14 limbs (57%) at a mean of 14 weeks. Reduction in ulcer size was noted in four of 14 (29%), and two limbs were not improved. There were no new ulcers. Residual perforating veins were noted in four of 18 limbs. None of the limbs with residual perforating veins had complete healing of ulceration. Operating room costs were higher than those associated with limited-incision open perforator ligation ($2570 vs $1883). CONCLUSION: These preliminary data suggest that when used as part of a treatment plan to correct deep and superficial venous insufficiency SEPS results in a high rate of wound healing, with no recurrent ulceration in this series. Increased operating room costs associated with longer operations and greater disposable expenses will likely be overcome by shortened length of stay and diminished wound complications. These findings emphasize the importance of ligating all incompetent perforating veins, as ulcer healing was never achieved when residual perforating veins were found at follow-up.

Clinical results of common strategies used to revise infrainguinal vein grafts.

PURPOSE: Patients who have failing infrainguinal bypass grafts or failed grafts reopened with lytic therapy represent a group at high risk of subsequent failure. Previous studies suggest that vein patch angioplasty and jump grafting may be less durable than interposition grafting as a method of correcting graft lesions. Our objective was to assess the value of various technical strategies for graft revision in a series of autogenous infrainguinal bypass grafts and to assess how these variables might affect cumulative graft patency (CGP) rates. METHODS: We retrospectively reviewed the clinical course, anatomic sites of revision, and type of revision performed on 67 grafts in 58 patients who underwent at least one revision from 1991 to 1995. Results were assessed with regression analysis and Kaplan-Meier estimates of CGP rates (p < 0.05 was considered significant). RESULTS: Sixty-seven vein grafts underwent revision of 112 anatomical sites in 95 operations. Forty-nine of 67 grafts were single-segment greater saphenous vein grafts and 18 were composite (> 1 segment) grafts, with an overall 5-year CGP rate of 72%. No difference was observed between the 4-year CGP rate in grafts with hemodynamically significant distal anastomotic stenoses repaired primarily with jump grafts (n = 20, 71% CGP rate) and those with stenoses found only in the graft body (n = 41, 89% CGP rate). Vein patch angioplasty was used primarily, but not exclusively, for focal graft body stenoses (n = 35), whereas interposition grafts (n = 11) were reserved for more diffuse strictures; no significant difference in 3-year CGP rates was observed (94% and 73%, respectively). CONCLUSION: Using an appropriate revision strategy that favors vein patch angioplasty for graft body lesions and jump grafts for distal anastomotic lesions, acceptable assisted patency rates can be achieved in grafts that are at risk for repeated failure.

Duplex assessment of venous reflux and chronic venous insufficiency: the significance of deep venous reflux.

PURPOSE: This study was undertaken to examine the role of superficial and deep venous reflux, as defined by duplex-derived valve closure times (VCTs), in the pathogenesis of chronic venous insufficiency. METHODS: Between January 1992 and November 1995, 320 patients and 500 legs were evaluated with clinical examinations and duplex scans for potential venous reflux. VCTs were obtained with the cuff deflation technique with the patient in the upright position. Imaging was performed at the saphenofemoral junction, the middle segment of the greater saphenous vein, the lesser saphenous vein, the superficial femoral vein, the profunda femoris vein, and the popliteal vein. Not all patients had all segments examined because tests early in the series did not examine the profunda femoris or lesser saphenous vein and because some patients had previous ligation and stripping or venous thrombosis. VCTs were examined for individual segment reflux, grouped into superficial and deep systems, and then correlated with the clinical stage as defined by the SVS/ISCVS original reporting standards in venous disease. Segment reflux was considered present if the VCT was greater than 0.5 seconds, and system reflux was considered present if the sum of the segments was greater than 1.5 seconds. Between-group differences were analyzed with analysis of variance and post hoc tests where appropriate. RESULTS: Sixty-nine limbs studied were in class 0, 149 limbs were in class 1, 168 limbs were in class 2, and 114 limbs were in class 3. VCTs in the superficial veins were significantly lower in class 0 than in the other clinical classes. There was no difference in superficial reflux in the symptomatic limbs (classes 1 to 3). Reflux VCTs in the superficial femoral and popliteal veins increased as the clinical symptoms progressed, with a significant increase in class 3 ulcerated limbs when compared with nonuclerated limbs. The incidence of deep venous reflux was 60% in class 3 limbs, compared with 29% in class 2 limbs, whereas the incidence of superficial venous reflux did not differ among the symptomatic limbs. Isolated superficial femoral and popliteal vein reflux was uncommon, even in class 3 limbs, but combined superficial femoral and popliteal vein reflux was found in 53% of class 3 limbs, compared with 18.5% of class 2 limbs. CONCLUSIONS: Reflux in the deep venous system plays a significant role in the progression of chronic venous insufficiency. Deep system reflux increases as clinical changes become more severe, with significant axial reflux contributing to ulcer formation.

Management of recurrent carotid stenosis: should asymptomatic lesions be treated surgically?

PURPOSE: The purpose of this study was to determine factors that may influence patient selection for surgery in recurrent carotid stenosis (RCS) and to contrast the results of primary and secondary carotid endarterectomy (CENDX) with regard to operative morbidity and stroke prevention. METHODS: Forty-eight patients who underwent CENDX for RCS (RCS-OP group) were compared with a contemporaneous group of 40 patients who on at least one post-CENDX duplex ultrasonography study had a greater than 50% stenosis but did not undergo operation (RCS-NO-OP group). This latter group was drawn from 1053 follow-up duplex studies in 348 patients who underwent primary CENDX between the years 1983 and 1993. Each of these two groups was compared with a metanalysis of six key series derived from the literature. RESULTS: No significant differences were seen in the demographics or the incidence of risk factors between the two groups except for a higher incidence of coronary artery disease (p < 0.03) and peripheral vascular disease (p < 0.001) in the RCS-OP group. The operation-specific stroke rate was 2.1%, and the 30-day mortality was also 2.1%. Symptomatic RCS was the indication in 56% of cases. Important anatomic differences were found between groups. The duplex/arteriographic degree of stenosis was greater than 90% in 75% of the patients in the RCS-OP group, whereas only 10% of the patients in the RCS-NO-OP group had greater than 80% stenosis, most being in the 50% to 80% range. An unexpected finding was the sudden progression to occlusion in 10 (25%) of 40 in the RCS-NO-OP group, with 2 (5%) of 10 of the occlusions presenting as unheralded strokes. Overall, a stroke without an antecedent transient ischemic attack occurred in 3 (7.5%) of 40 of patients in the RCS-NO-OP group, all in patients with greater than 75% stenosis on their last documented scan preceding the stroke. CONCLUSION: Given the relatively low stroke rate with surgery in the RCS-OP group (2.1%) and the higher incidence of unheralded strokes (7.5%) in the RCS-NO-OP group, a more aggressive approach may be warranted in patients with asymptomatic high-grade (> 75%) RCS, a strategy not unlike that adopted for primary CENDX.

Evaluation of carotid artery stenosis: is duplex ultrasonography sufficient?

PURPOSE: The purpose of this study was to compare the results of duplex ultrasonography and magnetic resonance angiography in the evaluation of carotid artery stenosis to determine whether ultrasonography alone is sufficient for preoperative evaluation. METHODS: This study consisted of a retrospective review of 33 patients who underwent 35 carotid endarterectomies. A total of 66 vessels were studied by both duplex ultrasonography and magnetic resonance angiography, and an overall correlation between the two studies was determined. RESULTS: A high correlation was found between duplex and magnetic resonance angiography with an r coefficient equal to 0.87 (Pearson's correlation coefficient) and kappa = 0.75. Discrepancies between the two studies or the presence of intracranial disease did not alter surgical decision making. CONCLUSION: Duplex ultrasonography alone can accurately determine the degree of internal carotid artery stenosis and when paired with careful clinical evaluation is a reliable and cost-effective method for evaluating surgical carotid disease.

Duplex-derived valve closure times fail to correlate with reflux flow volumes in patients with chronic venous insufficiency.

The best way to quantitate venous reflux is still a matter of debate. Duplex-derived valve closure time (VCTs) have been used recently because they can be measured easily. We examined the relationships between VCT and duplex-obtained quantitation of venous volume and between VCT and air plethysmography (APG). Sixty-nine legs in 45 patients with varying clinical degrees of chronic venous insufficiency were studied by duplex scan and APG. VCTs were compared with duplex-derived flow calculations and with APG-derived venous filling index and residual volume fraction. The patient's mean age was 47.5 +/- 13.9 years; the mean duration of their symptoms was 13 +/- 4 years. Twenty percent had a history of deep venous thrombosis, and 29% had undergone venous surgery. No correlation was found between VCT and flow volume or between VCT and flow at peak reflux at any of the anatomic locations studied: saphenofemoral junction, greater saphenous vein, lesser saphenous vein, superficial femoral vein, profunda femoris vein, and popliteal vein. Likewise, no correlation was found between total VCT and APG-derived venous filling index or between total flow volumes and APG-derived residual volume fraction. Total VCT and total flow volumes did, however, have a moderate correlation (r = 0.65; p = 0.0003). Duplex-derived VCTs, although extremely useful in determining the presence of reflux, do not correlate with the magnitude of reflux, and should not be used to quantitate the degree of reflux.

Primary varicose veins of the upper extremity: a report of three cases.

Primary varicose veins of the upper extremity are extremely rare. We present three cases and discuss cause, diagnosis, and treatment. Three patients, a 23-year-old man, a 31-year-old woman, and a 39-year-old man, were referred with symptomatic varicose veins of the arm. None of the patients had lower extremity varicosities. Diagnosis was made by physical examination, noninvasive and invasive procedures, and excluded vascular malformations. Surgical treatment, similar to that for lower extremity varicose veins, entailed ligation and stripping of the varicose veins. Ligation and stripping were performed and successfully eliminated the varicosities with prevention of recurrence with a mean follow-up of 17 months. Although primary varicose veins of the upper extremity are extremely rare, they can be readily diagnosed and successfully treated, similar to lower extremity varicose veins. Although not proven, the cause is likely identical to lower extremity varicose veins. Excellent functional and cosmetic results can be obtained with surgical treatment.

Superiority of balloon occlusion arteriography to reactive hyperemic arteriography in visualization of distal lower limb vessels.

Balloon occlusion arteriography was performed in 38 lower limbs; reactive hyperemic arteriography was also performed in 16 of these limbs. To assess the safety and utility of this technique the balloon occlusion arteriograms of all 38 patients were reviewed retrospectively by a vascular surgeon and vascular radiologist who were unaware of the patient's identity and ultimate treatment. After the arteriograms were reviewed and the outflow vessels identified, a decision was made regarding operability and optimal recipient vessel for distal bypass. Twenty-two of the 38 patients underwent balloon occlusion arteriography only, and 21/22 (95.5%) of these patients only had studies deemed adequate for surgical planning. Twelve of the 16 (75%) patients underwent both reactive hyperemic arteriography and balloon occlusion arteriography; potential distal outflow vessels not seen on reactive hyperemic arteriograms were observed on balloon occlusion arteriograms. In only 4/16 (25%) patients the balloon occlusion arteriograms did not yield additional information. No complications were associated with this technique. Approximately 8.5 g of iodine per run is used for balloon occlusion arteriography compared with approximately 37 g of iodine per run for reactive hyperemic arteriography. Balloon occlusion arteriography is a safe and accurate adjunctive technique that can be used when identification of lower limb vessels is critical.

Comparison of descending phlebography with quantitative photoplethysmography, air plethysmography, and duplex quantitative valve closure time in assessing deep venous reflux.

To assess the role of noninvasive tests--quantitative photoplethysmography, air plethysmography, and quantitative duplex scanning, we compared a group of normal (group N, eight limbs) volunteers to patients with severe chronic venous insufficiency who were stratified according to the degree of reflux seen on the current "gold standard," descending phlebography. Group M (10 limbs) had mild (grades 0 to 2) reflux, and group S (10 limbs) had severe (grades 3 to 4) reflux as determined by phlebography. Quantitative photoplethysmography could identify normal from abnormal limbs but could not distinguish the severity of reflux. Air plethysmography was used to calculate venous filling index, ejection fraction, and residual volume fraction. Ejection fraction was the same in all groups. Venous filling index could not significantly distinguish the degree of reflux (group M vs group S) but increased as reflux increased. Residual volume fraction was considerably higher in group S. Quantitative duplex valve closure time was measured in the superficial femoral and popliteal veins, with the values added together in each limb to give a total valve closure time (TVCT). A TVCT value greater than or equal to 4 seconds correlated best with severe phlebographic reflux, with a sensitivity of 90%, a specificity of 94%, and an accuracy of 93%. This value was confirmed as the best test for venous reflux by receiver operating characteristic curve analysis. Thus in the evaluation of patients with severe chronic venous insufficiency who are candidates for phlebography and surgery, quantitative duplex measurement of TVCT gives the best noninvasive assessment of the severity of deep venous reflux.

Femoral vein valvuloplasty: intraoperative angioscopic evaluation and hemodynamic improvement.

Femoral vein valvuloplasty (FVV) is the operation of choice for primary valvular incompetence, but this procedure is highly operator dependent for judging the competence of the valve repair during surgery. We have reviewed our experience with FVV, focusing on the utility of angioscopic-guided valve repair and hemodynamic results. Nine limbs in six patients underwent superficial FVV. There were four men and two women; the average age was 49 years (range 32 to 62 years). All limbs were Society for Vascular Surgery/International Society for Cardiovascular Surgery clinical stage III (venous ulcer), and descending phlebography showed grade 4 reflux in six limbs, grade 3 reflux in one limb, and grade 2 reflux in two limbs. In addition to FVV, five limbs underwent subfascial ligation of incompetent perforators and three limbs underwent ligation and stripping of superficial varicosities. Two limbs underwent polytetrafluoroethylene wrapping of the valvuloplasty. The last five valvuloplasties underwent angioscopic evaluation of the repair, and the last two procedures were closed valvuloplasties (without venotomy). Follow-up averaged 20.3 months (range 2 to 51 months). In all patients ulcers healed without recurrence. There were two perioperative deep vein thromboses in the polytetrafluoroethylene wrapped repairs. All superficial femoral veins were patent by duplex scanning at the time of follow-up. Venous refill time measured by light reflection rheography did not improve after surgery. Venous filling index measured by air plethysmography showed near normalization (3.83 +/- 0.82) after angioscopically guided FVV.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and hemodynamic results of bypass to isolated tibial artery segments for ischemic ulceration of the foot.

Patients with ischemic ulceration of the foot and no continuous tibial or inframalleolar vessels acceptable for bypass are often treated with primary amputation. We have performed autogenous vein bypass to isolated tibial artery segments (ITAS) in nine patients with ischemic foot ulcers and no other outflow options. We reviewed the clinical and hemodynamic results of these bypasses to assess the efficacy of this approach. Hemodynamic comparisons of these ITAS bypasses were made to a concurrent series of 26 bypasses to intact tibial arteries and 24 inframalleolar artery bypasses assessed during routine follow-up. Eight of the bypasses originated from the above-knee popliteal artery and one from the profunda femoris artery. Recipient vessels were the anterior tibial (seven), peroneal (one), and posterior tibial (one) arteries. Although mean ankle brachial indices (ABI) increased significantly from 0.26 +/- 0.06 preoperatively to 0.75 +/- 0.04 postoperatively (p = 0.0015), ITAS bypass patients had lower mean postoperative ABIs than patients with bypasses to intact tibial (ABI = 0.98 +/- 0.03, p = 0.0001) or pedal arteries (ABI = 1.02 +/- 0.04, p = 0.0005). Similarly, duplex scan-derived peak systolic flow velocities of the ITAS bypasses (mean: 52.9 +/- 5.8 cm/sec) were lower than those of intact tibial artery bypasses (mean: 80.1 +/- 6.1 cm/sec, p = 0.02) but did not differ from those of pedal bypasses (mean: 59.5 +/- 3.5 cm/sec, p = 0.34). No ITAS bypass grafts have failed during a mean follow-up of 12.3 +/- 2.7 months. Although wound healing was prolonged (mean: 3.1 +/- 0.6 months), the wounds of eight of nine patients eventually healed, with three patients requiring minor amputations (one digital amputation and two transmetatarsal amputations). Although the hemodynamic results of ITAS bypass are inferior to those of more conventional bypasses, the early patency rates and successful healing of ischemic wounds confirm that it is a valid alternative in the threatened limb with no other outflow options.

Neurotensin stimulates exocytotic histamine secretion from rat mast cells and elevates plasma histamine levels.

1. Neurotensin stimulated histamine release and granule extrusion when applied to isolated rat peritoneal mast cells. 2. This secretory response was prevented by the removal of calcium or energy and was not accompanied by the release of lactic dehydrogenase. 3. The secretory response produced by neurotensin was prevented by prior treatment of mast cells with cromoglycate. 4. The intravenous injection of neurotensin into anaesthetized rats produced a rapid and significant increase in the level of blood histamine that was dependent upon the dose of neurotensin. 5. Treatment of rats with compound 48/80, 24 hr before neurotensin, abolished the elevation in blood histamine caused by neurotensin. The intravenous injection of cromoglycate 1-2 min before neurotensin greatly reduced the response to neurotensin. 6. The intradermal injection of neurotensin (0.03-30 p-mole) increased capillary permeability in rats pre-treated intravenously with Evans Blue. This response was abolished by the antihistamine, diphenhydramine. Increasing the dose of neurotensin to 300 p-mole partially overcame this inhibition by diphenhydramine. 7. Our results demonstrate that neurotensin can elicit an exocytotic secretory response from isolated rat peritoneal mast cells and elevate histamine levels in blood. It is suggested that some of neurotensin's physiological effects may be due to stimulation of mast cell secretion.