The ICAROS registry of carotid artery stenting. Imaging in Carotid Angioplasties and Risk of Stroke

ICAROS (Imaging in Carotid Angioplasties and Risk Of Stroke) is a multicenter international registry of carotid artery stenting designed to determine the criteria for identifying patients at higher or lower risk of periprocedural stroke and restenosis at 1 year. The aim of the registry is to improve patient selection and consequently reduce the risk of cerebral embolization during carotid stenting. The registry is open to all interventionists performing carotid stenting, and the participants are free to apply their own endovascular techniques and devices, including cerebral protection mechanisms. All cerebral ischemic events following the procedure will be reported. Follow-up surveillance to 1 year will include periodic duplex scanning and neurological examinations. Echographic plaque images will be standardized for comparison, processed for echodensity, and analyzed by computer at the Registry Center. Correlation will be investigated between the echographic index (gray-scale median) and the risk of embolism and outcome of carotid stenting.

Correlates of embolic events detected by means of transcranial Doppler in patients with carotid atheroma

PURPOSE

This study identified in patients with carotid plaques the associations of emboli detected by means of transcranial Doppler (TCD) with cerebrovascular symptoms, brain computed tomography (CT) infarction patterns, and the attributes of plaques (echodensity, degree of stenosis).

METHODS

Eighty carotid plaques (in 59 patients), producing 50% to 99% stenosis, were imaged on duplex scanning and analyzed echomorphologically in a computer with the gray scale median (GSM). The GSM facilitated the quantitative distinction of dark (low GSM) from bright (high GSM) plaques. Stenosis was assessed with duplex scanning. Emboli were counted on TCD in the ipsilateral middle cerebral artery for half an hour. The brain CT infarction patterns (pattern A: discrete subcortical and cortical; pattern B: hemodynamic, diffuse white matter lesions, basal ganglia infarctions, lacunes) and normal CT and cerebrovascular symptoms on the ipsilateral hemisphere were noted.

RESULTS

Emboli were more frequent in symptomatic (median count, 3) than asymptomatic (median count, 0) hemispheres (Mann-Whitney U test, P =.031) and in hemispheres with pattern A infarction (median count, 3.5) than in hemispheres with pattern B infarction or normal CT (median count, 0; Kruskal-Wallis test, P =.047). The increased embolic count was associated with decreased GSM (Spearman correlation, P =.045, r = -0.22), but not with high degrees of stenosis (Spearman correlation, P =.44, r = 0.086).

CONCLUSION

Emboli were more frequent in symptomatic than asymptomatic hemispheres and in CT pattern A harboring hemispheres than in CT pattern B or normal hemispheres. They were more frequent in the presence of low-plaque echodensity, but not in the presence of a high degree of stenosis. These data support the embolic nature of cerebrovascular symptomatology and CT pattern A infarctions.

Stroke: management and rehabilitation. Part III of III

The aim of this review is to present the current knowledge regarding stroke. It appears in three parts (in part I the epidemiology, clinical picture, and risk factors were discussed, while part II dealt with the pathogenesis, investigations, and prognosis). In this part (III) the management is presented. In an acute stroke the role of the following is discussed in detail: Thrombolysis, anticoagulant agents, and prophylactic neuroprotection with pharmacologic agents. For the prevention of stroke apart from the risk factors, which were presented in part I, the current knowledge with pharmacologic agents is discussed. Also the role of carotid endarterectomy, extracranial-intracranial bypass surgery, carotid artery angioplasty and stenting, and the treatment of cerebral hemorrhage are described. Finally the means and possibilities of rehabilitation are discussed.

Investigation of chronic venous insufficiency: A consensus statement (France, March 5-9, 1997)

This consensus document provides an up-to-date account of the various methods available for the investigation of chronic venous insufficiency of the lower limbs (CVI), with an outline of their history, usefulness, and limitations. CVI is characterized by symptoms or signs produced by venous hypertension as a result of structural or functional abnormalities of veins. The most frequent causes of CVI are primary abnormalities of the venous wall and the valves and secondary changes due to previous venous thrombosis that can lead to reflux, obstruction, or both. Because the history and clinical examination will not always indicate the nature and extent of the underlying abnormality (anatomic extent, pathology, and cause), a number of diagnostic investigations have been developed that can elucidate whether there is calf muscle pump dysfunction and determine the anatomic extent and severity of obstruction or reflux. The difficulty in deciding which investigations to use and how to interpret the results has stimulated the development of this consensus document. The aim of this document was to provide an account of these tests, with an outline of their usefulness and limitations and indications of which patients should be subjected to the tests and when and of what clinical decisions can be made. This document was written primarily for the clinician who would like to learn the latest approaches to the investigation of patients with CVI and the new applications that have emerged from recent research, as well as for the novice who is embarking on venous research. Care has been taken to indicate which methods have entered the clinical arena and which are mainly used for research. The foundation for this consensus document was laid by the faculty at a meeting held under the auspices of the American Venous Forum, the Cardiovascular Disease Educational and Research Trust, the European Society of Vascular Surgery, the International Angiology Scientific Activity Congress Organization, the International Union of Angiology, and the Union Internationale de Phlebologie at the Abbaye des Vaux de Cernay, France, on March 5 to 9, 1997. Subsequent input by co-opted faculty members and revisions in 1998 and 1999 have ensured a document that provides an up-to-date account of the various methods available for the investigation of CVI.

The impact of isolated lesser saphenous vein system incompetence on clinical signs and symptoms of chronic venous disease

PURPOSE

The purpose of this study was to determine the patterns of isolated lesser saphenous vein (LSV) system incompetence and correlate the distribution and extent of such reflux with symptoms and signs of chronic venous disease (CVD).

METHODS

During a 3-year period, 2254 limbs in 1682 patients with signs and symptoms of CVD were evaluated with color flow duplex scanning. Extremities with isolated reflux in the LSV system were selected for this study. Limbs with perforating venous reflux connected to this system only were also included. Limbs that had marked reflux in the greater saphenous or deep vein, that had a documented history of deep venous thrombosis, and that previously underwent surgery or sclerotherapy were excluded. The clinical severity of the limbs was graded with the CEAP classification system.

RESULTS

There were 226 limbs in 200 patients with reflux in the LSV system; 61% were female patients with a mean age of 49 years (range, 18-82 years). There were 174 patients (87%) with unilateral and 26 with bilateral disease, and 41% of the limbs belonged in CVD class 2, 26% in class 3, 12% in class 4, 3.5% in class 5, and 3% in class 6. Classes 0 and 1 were present in 14.5% of the limbs. Symptoms were present in 139 limbs (61.5%). Some degree of ache or burning sensation was the most frequent symptom (41%), followed by itching (32%), heaviness (29%), cramps (24%), and restless limbs (18%). Reflux in the main trunk of the LSV was the most prevalent (177 limbs [78%]), followed by the saphenopopliteal junction (146 limbs [64.6%]), the vein of Giacomini (39 limbs [17%]) and the gastrocnemial vein (23 limbs [10%]). Reflux involving both the saphenopopliteal junction and the LSV was seen in 50% of limbs, but almost any other combination of reflux was present, which indicated the complexity of this system. Perforator vein incompetence was detected in 56 limbs (25%). We found 83 perforator veins, resulting in a mean of 1.5 veins per limb. Both the number of incompetent perforator veins and the extent of superficial reflux correlated with clinical severity. Four main types of termination of the LSV were identified with at least nine variations. The LSV was duplicated for at least half of its length in five limbs (2.2%). Nonsaphenous reflux was detected in seven limbs (3.1%). Superficial vein thrombosis in the LSV system was found in eight limbs (3.5%), and in the gastrocnemial vein it was found in four (1.8%).

CONCLUSIONS

Isolated LSV system incompetence can cause the entire range of signs and symptoms of CVD. Clinical deterioration is associated with a longer extent of reflux and perforator incompetence. Classes 2 to 4 are the most frequent clinical presentations, whereas classes 5 and 6 are uncommon. The complex anatomy of this system and the great variation in the patterns of reflux warrant the use of color flow duplex scanning before planning treatment.

Echomorphologic and histopathologic characteristics of unstable carotid plaques

BACKGROUND AND PURPOSE

Our hypothesis was that the carotid plaques associated with retinal and cerebrovascular symptomatology and asymptomatic presentation may be differ from each other. The aim of this study was to identify the sonographic and histopathologic characteristics of plaques that corresponded to these three clinical manifestations.

METHODS

The echo process involved duplex preoperative imaging of 71 plaques (67 patients, 21 plaques were associated with retinal, 25 with cerebrovascular symptoms, and 25 were asymptomatic), which was performed in a longitudinal fashion. Appropriate frames were captured and digitized via S-video signal in a computer and digitized sonograms were normalized by two echo-anatomic reference points: the gray scale median (GSM) of the blood and that of the adventitia. The GSM of the plaques was evaluated to distinguish dark (low-GSM) from bright (high-GSM) plaques. Subsequent to endarterectomy, the plaques were sectioned transversely, and a slice at the level of the largest plaque area was examined for the relative size of necrotic core and presence of calcification and hemorrhage.

RESULTS

Retinal symptomatology was associated with a hypoechoic plaque appearance (median GSM: 0), asymptomatic status with a hyperechoic plaque appearance (median GSM: 34), and cerebrovascular symptomatology with an intermediate plaque appearance (median GSM: 16) (P = .001). The histopathologic characteristics did not disclose differences between the three clinical groups. The hypoechoic plaque appearance was associated only with the presence of hemorrhage (median GSM for the hemorrhagic plaques, 6, and for the non-hemorrhagic ones, 20 [P = .04]). The relative necrotic core size and the presence of calcification did not show any echomorphologic predilection.

CONCLUSION

Our results showed that distinct echomorphologic characteristics of plaques were associated with retinal and cerebrovascular symptomatology and asymptomatic status. Histopathologically, only the presence of hemorrhage proved to have an echomorphologic predilection.

The significance of the cerebral collateral capacity in patients with carotid atheroma

OBJECTIVES

to identify the echodensity, stenosis of carotid plaques and cerebral collateral capacity that were associated with various ipsilateral presentations (retinal, cerebrovascular, asymptomatic).

DESIGN

cross-sectional study.

MATERIALS

forty-four patients, with 44 plaques associated with various presentations, were studied.

METHODS

the duplex images of the plaques were analysed echomorphologically in a computer by means of Grey Scale Median (GSM) [hypoechoic (low GSM), hyperechoic (high GSM)]. The percentage (%) reduction of the mean velocity in the middle cerebral artery (PRMCA) on transcranial Doppler, during clamping in carotid endarterectomy, was evaluated to distinguish the competent cerebral collateral supply (low PRMCA) from the non-competent one (high PRMCA).

RESULTS

the retinal symptoms were associated with plaques of low median GSM (0), severe median stenosis (90%) and low median PRMCA (0.31) as contrasted with the cerebrovascular symptoms (17, 84%, 0.47, respectively) and asymptomatic status (32, 83%, 0.4, respectively) [(p =0.038 (GSM), p =0.67 (stenosis), p=0.15 (PRMCA)]. The retinal and the cerebrovascular symptoms were distinct in terms of PRMCA (p=0.045).

CONCLUSIONS

the retinal symptoms were produced by hypoechoic and possibly embologenic plaques, whereas the cerebrovascular ones possibly by the combination of carotid embolism and a non-competent cerebral collateral circulation. Asymptomatic status was associated with the absence of any relevant mechanism.

Stroke: pathogenesis, investigations, and prognosis--Part II of III

The aim of this review is to present the current knowledge regarding stroke. It will appear in three parts (in part I the epidemiology, clinical picture, and risk factors were discussed, while part III will consist of the management and rehabilitation). In the present part (II) the pathogenetic and pathophysiologic aspects of stroke are described. Regarding the investigations apart from the history and clinical examination and general investigations, the following specialized investigations and their role are discussed in detail: Computed tomography (CT), magnetic resonance imaging (MRI), xenon-blood-flow, positron emission tomography (PET), cerebral angiography, magnetic resonance angiography (MRA), ultrasonography, transcranial Doppler (TCD), echocardiography, Holter monitoring, and biopsies. In addition, taking into account the information from the above-cited modalities a prognosis for the final outcome is presented.

The efficacy of the new SCD response compression system in the prevention of venous stasis

OBJECTIVE

The current commercially available sequential intermittent pneumatic compression device used for the prevention of deep venous thrombosis has a constant cycle of 11 seconds' compression and 60 seconds' deflation. This deflation period ensures that the veins are filled before the subsequent cycle begins. It has been suggested that in some positions (eg, semirecumbent or sitting) and with different patients (eg, those with venous reflux), refilling of the veins may occur much earlier than 60 seconds, and thus a more frequent cycle may be more effective in expelling blood proximally. The aim of the study was to test the effectiveness of a new sequential compression system (the SCD Response Compression System), which has the ability to detect the change in the venous volume and to respond by initiating the subsequent cycle when the veins are substantially full.

METHODS

In an open controlled trial at an academic vascular laboratory, the SCD Response Compression System was tested against the existing SCD Sequel Compression System in 12 healthy volunteers who were in supine, semirecumbent, and sitting positions. The refilling time sensed by the device was compared with that determined from recordings of femoral vein flow velocity by the use of duplex ultrasound scan. The total volume of blood expelled per hour during compression was compared with that produced by the existing SCD system in the same volunteers and positions.

RESULTS

The refilling time determined automatically by the SCD Response Compression System varied from 24 to 60 seconds in the subjects tested, demonstrating individual patient variation. The refilling time (mean +/- SD) in the sitting position was 40.6 +/- 10. 0 seconds, which was significantly longer (P <.001) than that measured in the supine and semirecumbent positions, 33.8 +/- 4.1 and 35.6 +/- 4.9 seconds, respectively. There was a linear relationship between the duplex scan-derived refill time (mean of 6 readings per leg) and the SCD Response device-derived refill time (r = 0.85, P <. 001). The total volume of blood (mean +/- SD) expelled per hour by the existing SCD Sequel device in the supine, semirecumbent, and sitting positions was 2.23 +/- 0.90 L/h, 2.47 +/- 0.86 L/h, and 3.28 +/- 1.24 L/h, respectively. The SCD Response device increased the volume expelled to 3.92 +/- 1.60 L/h or a 76% increase (P =.001) in the supine position, to 3.93 +/- 1.55 L/h or a 59% increase (P =. 001) in the semirecumbent position, and to 3.97 +/- 1.42 L/h or a 21% increase (P =.026) in the sitting position.

CONCLUSIONS

By achieving more appropriately timed compression cycles over time, the new SCD Response System is effective in preventing venous stasis by means of a new method that improves on the clinically documented effectiveness of the existing SCD system. Further studies testing its potential for improved efficacy in preventing deep venous thrombosis are justified.

New information on the value of plaque characterisation--relation to symptoms

This paper reviews the literature on the significance of carotid plaque echomorphology and degree of stenosis in relation to the different types of cerebrovascular symptomatology (amaurosis fugax, hemispheric transient ischaemic attacks, stroke) and the asymptomatic status. It provides evidence that amaurosis fugax is associated with hypoechoic and severely stenosed plaques, the hemispheric transient ischaemic attacks and stroke are associated with plaques of intermediate echodensity and stenosis while the asymptomatic status is associated with hyperechoic and moderately stenosed plaque. It lends support to the notion that plaque hypoechoicity is associated with embologenicity. It supports the view that the severe carotid stenosis facilitates the opening of the cerebral collateral circulation and that amaurosis fugax is associated with an "opened" cerebral collateral supply as contrasted to the cerebrovascular symptomatology. It proposes the inclusion of the cerebral collateral circulation as a stroke risk factor along with the plaque echomorphology and the degree of stenosis in the natural history studies of asymptomatic individuals with carotid bifurcation plaques.

Stroke: epidemiology, clinical picture, and risk factors--Part I of III

The aim of this review is to present the current knowledge regarding stroke. It will appear in three parts (in part II the pathogenesis, investigations, and prognosis will be presented, while part III will consist of the management and rehabilitation). In the current part (I) the definitions of the clinical picture are presented. These include: amaurosis fugax, vertebrobasilar transient ischemic attack, and stroke (with good recovery, in evolution and complete). The role of the following risk factors is discussed in detail: age, gender, ethnicity, heredity, hypertension, cigarette smoking, hyperlipidemia, diabetes mellitus, obesity, fibrinogen and clotting factors, oral contraceptives, erythrocytosis and hematocrit level, prior cerebrovascular and other diseases, physical inactivity, diet and alcohol consumption, illicit drug use, and genetic predisposition. In particular, regarding the carotid arteries, the following characteristics are analyzed: atheroma, carotid plaque echomorphology, carotid stenosis, presence of ulcer, local variations in surface deformability, pathological characteristics, and dissection. Finally the significance of the cerebral collateral circulation and the conditions predisposing to cardioembolism and to cerebral hemorrhage are presented.

[Femoral artery pseudo-aneurysms--changes in treatment, report of 7 years]

The femoral artery remains the most used peripheral site for radiological catheter access. With a greater number of both diagnostic and therapeutic procedures being performed by interventional radiologists and cardiologists, and with larger catheters being used for stenting and endovascular grafting, the incidence of iatrogenic pseudo-aneurysms reported has reached as high as 0.5-2%. Ideally, they should thrombus spontaneously. However, when this does not occur, management options include: observation, ultrasound-guided obliterative compression, direct thrombin injection, embolization, stent graft insertion, and very rarely-surgery. During a 7-year period (1992-1999) we treated 131 cases of femoral artery false aneurysms. Until 1998 ultrasound-guided compression-obliteration, with a 95% success rate, was our method of choice. Since 1998, direct thrombin injection, with 100% success in 24 cases, has become our preferred method. It is pain-free, fully successful even in anticoagulated patients, and is currently our treatment of choice.

Patterns of cerebrovascular symptomatology associated with carotid atheroma

The aim of this study was to identify ultrasonic tissue characteristics and stenosis of carotid plaques that correspond to amaurosis fugax, hemispheric transient ischaemic attack, and stroke. At total of 146 symptomatic carotid plaques (136 patients) associated with amaurosis fugax, hemispheric transient ischaemic attack, stroke, and having 50-99% stenosis on duplex, were studied. These plaques were imaged on duplex, captured in a computer and their grey scale median was evaluated to distinguish the dark (low grey scale median) from the bright (high grey scale median) plaques. Stenosis was assessed on duplex. The amaurosis fugax group corresponded to carotid plaques with low grey scale median and severe stenosis, as contrasted with the other two groups (hemispheric transient ischaemic attack and stroke) (P < 0.05). These results suggested that amaurosis fugax was dependent only on the instability of carotid plaques, whereas hemispheric transient ischaemic attack and stroke were both dependent on carotid plaques and other pathogenetic factors.

Reproducibility of computer-quantified carotid plaque echogenicity: can we overcome the subjectivity?

BACKGROUND AND PURPOSE

We sought to assess the reproducibility, interobserver variability, and application to clinical studies of a new method for the quantitative assessment of carotid plaque echogenicity.

METHODS

Carotid plaques were scanned with the use of ultrasound, and their images were stored in a computer. They were normalized by assigning certain gray values to blood and adventitia, and the gray scale median (GSM) was used to quantify their echogenicity. The variability between storage media, between degrees of magnification, and between probes was assessed. The method was applied to 232 asymptomatic carotid plaques causing 60% to 99% stenosis in relation to the presence of ipsilateral CT-demonstrated brain infarcts. In all parts of the study the plaque GSM was measured before and after normalization to evaluate its effect. Interobserver agreement for the scanning process was assessed.

RESULTS

The GSM mean difference before and after normalization for variability studies of storage media, degrees of magnification, and probes was -14.5 and -0.12, 2.24 and 1.68, and -8.3 and -0.7, respectively. The median GSM of plaques associated with ipsilateral nonlacunar silent CT-demonstrated brain infarcts was 14, and that of plaques that were not so associated was 30 (P:=0.003). The interobserver GSM difference was -0.05 (95% CI, -1.7 to 1.6).

CONCLUSIONS

Our method decreases the variability between storage media and between probes but not the variability between degrees of magnification. It separates echomorphologically the carotid plaques associated with silent nonlacunar CT-demonstrated brain infarcts from plaques that are not so associated.

Femoral atherosclerosis in an older British population: prevalence and risk factors

Most estimates of the prevalence of peripheral atherosclerosis have been based on intermittent claudication or lower limb blood flow. The aim of this study was therefore to determine the prevalence of underlying femoral plaque, and to determine its association with other cardiovascular disease and risk factors. Presence of plaque was identified using ultrasound in a random sample of men (n=417) and women (n=367) aged 56-77 years. Coexistent cardiovascular disease, exercise and smoking were determined by questionnaire, blood pressure was recorded, and serum cholesterol and plasma fibrinogen were determined. Of the 784 subjects that were scanned, 502 (64%) demonstrated atherosclerotic plaque. Disease prevalence increased significantly with age (P<0.0001), and was more common in men (67.1 vs. 59.4%, P<0.05). Subjects with femoral plaque had a significantly greater odds of previous ischaemic heart disease (OR 2. 2, 95% CI 1.3, 3.7) and angina (OR 1.7, 95% CI 1.03, 2.7), but not of stroke or leg pain on exercise. Current and ex-smoking, raised serum total cholesterol and plasma fibrinogen levels, but not blood pressure, were associated with an increased risk of femoral plaque, independent of age and sex. Frequent exercise and a high HDL cholesterol were significantly associated with lower risk. In conclusion, therefore, atherosclerotic disease of the femoral artery affects almost two-thirds of the population in late middle age. It is associated with an increased prevalence of ischaemic heart disease and angina, but whether detecting at risk individuals using ultrasound offers advantages over simpler and less expensive risk factor scoring requires evaluation in trials.

Tissue response to an expanded polytetrafluoroethylene external valve support device: a histologic study in dogs

Expanded polytetrafluoroethylene (ePTFE) external valve support devices (EVS) have been used successfully in patients to restore valve function in leg veins with incompetent valves when incompetence is due to dilatation of the vein walls or elongation of the valve leaflet edges. To assess tissue response to these devices, the authors implanted 12 of them in dogs, wrapping the devices around veins in the head and neck. The dogs recovered from the implantation procedure uneventfully, and the veins remained patent on color flow Doppler scanning. Gross and histologic evaluations of vein segments and attached EVS devices after sacrifice of the dogs 30 days postoperatively showed that the ePTFE devices did not affect vein patency or the cellular composition or architecture of vein walls. There were no adverse tissue reactions to the EVS and no thrombus formation in the veins to which the EVS had been applied. Tissue attachment to the EVS was apparent in all specimens. These histologic results support clinical experiences indicating that the ePTFE EVS device is safe to use in external valvuloplasty for the treatment of venous incompetence.

Expanded polytetrafluoroethylene in external valvuloplasty for superficial or deep vein incompetence

The authors evaluated the long-term safety of expanded polytetrafluoroethylene (ePTFE) implants used in external valvuloplasty for treatment of incompetence of the long saphenous and common and superficial femoral veins. During a 15-year period patients with superficial and/or deep venous disease and hypertension due to pure superficial or deep vein incompetence underwent an external valvuloplasty with ePTFE sutures, or an ePTFE cardiovascular patch placed as a sleeve around the incompetent vein segment, or an ePTFE tubular graft placed around the venous segment. Postoperative follow-up evaluations consisted of clinical examinations, high-resolution ultrasonography, and color duplex scanning, and a complete blood count performed at 1, 3 and 6 months, and repeated for at least 4 years, every 2 years after the procedure. A total of 101 patients (38 men and 63 women; mean [+/- sd] age, 44+/-12 years) underwent external valvuloplasty between January 1983 and December 1998; 82 of them completed the 4-year follow-up. Forty of the 82 patients had been operated on for superficial vein incompetence, 42 for deep vein incompetence. Overall, the mean follow-up time was 7.8+/-3.6 years (range, 4 to 13). There were no infections, thromboses,foreign-body reactions to the ePTFE implants, or other prosthesis-related complications requiring explantation. One granuloma (noninfected) developed in association with a tubular ePTFE implant around a long saphenous vein, but it did not necessitate implant removal. Seven patients required (at least after 4 years) a second procedure for recurrent or new venous incompetence. Therefore, in this observational study, ePTFE implants used to treat or correct venous incompetence were well tolerated on a long-term basis.

PGE(1) treatment of severe intermittent claudication (short-term versus long-term, associated with exercise)--efficacy and costs in a 20-week, randomized trial

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 980 patients (883 completed the study) with an average total walking distance of 85.5 +/-10 m (range 22-119). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks. In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP phase 2 treatment was performed in 2 days by a 2-hour infusion (first day: morning 20 microg, afternoon 40 microg; second day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate tolerability or side effects. Full dosage (60 microg bid) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks and at 20 weeks in the STP more than in the LTP group. At 4 weeks the variation (increase) in pain-free walking (PFWD) was 167.8% (of the initial value) in the LTP group and 185% in the STP group (p<0.05). At 4 weeks the variation (increase) in total walking distance (TWD) was 227.6% of the initial value in the LTP group and 289% in the STP group (p<0.05). At 20 weeks the increase in PFWD was 496% of the initial value in the LTP group vs 643% in the STP group (147% difference; p<0.02). The increase in TWD was 368% in the LTP group and 529% in the STP group (161% difference; p<0.02). In both groups there was a significant increase in PFWD and TWD at 4 and 20 weeks, but results obtained with STP are better considering both walking distances. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 6.3% of the treated subjects in the LTP and 3% in the STP. Average cost of LTP was 6,664 Euro; for STP the average costs was approximately 1,820 E. The cost to achieve an improvement in walking distance of 1 m was 45.8 E with the LTP and 8.5 E with the STP (18% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,989 E vs. 421 E with STP (p<0.02). Between-group analysis favors STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE, treatment. With STP less time is spent in infusion and more in the exercise program. STP reduces costs, speeds rehabilitation, and may be easily used in a larger number of nonspecialized units.

Effects of shock waves on the microcirculation in critical limb ischemia (CLI) (8-week study)

Shock waves (SWs) are used to control and decrease pain in several clinical conditions (e.g., painful elbow and shoulder, etc). This clinical effect may be due to cellular stunning of the tissues (particularly nervous components) in the area treated with SW. It may also be the consequence of unknown metabolic actions on tissues, which may include changes in cellular permeability and the liberation of proteins and mediators locally acting on pain and nerve endings. The aim of this study was to evaluate the reduction in pain and the microcirculation improvement induced by SWs treatment in an 8-week study in patients with chronic limb ischemia (CLI). Patients with CLI (15 with rest pain only and 15 with rest pain and limited distal necrosis) were included. The treatment was based on a 30-minute SWs session, three times weekly for 2 weeks. Clinical and microcirculatory evaluation were performed with laser Doppler Po2 and Pco2 measurements. Pain was measured with an analogue scale line. A Minilith SL1 (Storz Medical, Switzerland) litotriptor was used. The parabolic reflector is coupled to the skin with a silicon water cushion. Focal pressure was adjusted between 6 and 70 Mpa in eight steps. The energy flux density was variable from 0.03 to 0.5 mJ/mm2. Focal diameter and distance were defined (depth of target within the patient's foot of about 70 mm). The coded intensity used in this study was between 6 and 8 and the application time was 20 min (at four impulses per second). Twenty-eight of the 30 patients with CLI (15 with rest pain only and 13 with necrosis) completed the study. The treatment was well tolerated. Blood pressure was unchanged after 8 weeks while the increase in laser Doppler flux was significant (p<0.05) (at all measurements after treatment). The ORACLE score at 1 and 8 weeks was decreased (p<0.05). The same trend was observed with the analogue scale line for pain (p<0.05). PO2 increased (p<0.05) and Pco2 decreased (p<0.05). Tibial pressure did not change. All patients observed an increase in their subjective pain-free walking distance. The improvement was still present after 8 weeks. In a separate subset of 37 patients (mean age 60+/-9 years; males) with CLI, a SWs dose-finding evaluation was performed. Flux changes were measured at the dorsum of the foot. Three treatment plans were used: (a) 20-minute SW treatment only once; (b) 20-minute SWs treatment every 2 days for 1 week; (c) 20 minutes every day for 1 week. Treatments were well tolerated. A different increase in flux was observed on the basis of different treatments. Flux variations generally indicated that increased SWs dosage was associated with proportional flux increase. Flux improvement was still present after 4 weeks. SWs treatment in CLI produced changes both in the microcirculation and on pain. These preliminary results are comforting and open new research options to be explored in the near future.

Endovenous management of saphenous vein reflux. Endovenous Reflux Management Study Group

PURPOSE

This study assessed clinical outcomes of two catheter-based endovenous procedures to eliminate or greatly mitigate saphenous vein reflux.

MATERIALS AND METHODS

A computer-controlled, dedicated generator and two catheter designs were used to treat 210 patients at 16 private clinic and university centers in Europe. The Closure catheter applied resistive heating over long vein lengths to cause maximum wall contraction for permanent obliteration; the Restore catheter induced a short subvalvular constriction to improve the competence of mobile but nonmeeting leaflets.

RESULTS

Closure treatment caused acute obliteration in 141 (93%) of 151 limbs; Restore treatment, shrinking one or more valves, acutely reduced reflux to less than 1 second in 41 (60%) of 68 limbs. Closure treatments were associated with early recanalization (6%), paresthesias (thigh, 9%; leg, 51%; P <.001), 3 skin burns, and 3 deep-vein thrombus extensions, with 1 embolism. Restore treatments were thrombogenic (16%) despite prophylactic anticoagulation, and treated valves enlarged over 6 weeks, becoming less competent. Clinical Efficacy Assessment Project clinical class was significantly improved after both treatments, up to 1 year. At 6 months, 87% of 53 Closure patients were class 0 or 1, 75% were symptom-free, and 96% of 55 treated limbs were completely free of reflux. Fourteen of 31 Restore patients (45%) had no symptoms, but 55% were class 2 or lower and only 19% had less than 1-second reflux.

CONCLUSION

Closure treatment is clinically effective, albeit with offsetting complications and early failures; these are being addressed through four procedural modifications. Restore valve shrinking, although conceptually attractive, is too problematic to be competitive with Closure treatment or saphenectomy.

Nomograms used to define the short-term treatment with PGE(1) in patients with intermittent claudication and critical ischemia. The ORACL.E (Occlusion Revascularization in the Atherosclerotic Critical Limb) Study Group. The European Study

Infusional, cyclic PGE1 treatment is effective in patients with intermittent claudication and critical limb ischemia (CLI). One of the problems related to chronic PGE1 treatment in vascular diseases due to atherosclerosis is to evaluate the variations of clinical conditions due to treatment in order to establish the number of cycles per year or per period (in severe vascular disease reevaluation of patients should be more frequent) needed to achieve clinical improvement. In a preliminary pilot study a group of 150 patients (mean age 67+/-12 years) with intermittent claudication (walking range from 0 to 500 m) and a group of 100 patients with CLI (45% with rest pain, and 55% gangrene; mean age 68 +/-11 years) the number of PGE1 cycles according to the short-term protocol (STP) needed to produce significant clinical improvement was preliminarily evaluated. Considering these preliminary observations, the investigators established a research plan useful to produce nomograms indicating the number of cycles of PGE1-STP per year needed to improve the clinical condition (both in intermittent claudication and CLI). A significant clinical improvement was arbitrarily defined as the increase of at least 35% in walking distance (on treadmill) and/or the disappearance of signs and symptoms of critical ischemia in 6 months of treatment in at least 75% of the treated patients. With consideration of the results obtained with the preliminary nomograms a larger validation of the nomograms is now advisable. A cost-effectiveness analysis is also useful to define the efficacy of treatment on the basis of its costs. The publication of this report in two angiological journals (Angeiologie and Angiology) will open the research on nomograms to all centers willing to collaborate to the study. The data are being collected in the ORACL.E database and will be analyzed within 12 months after the publication of this report.

The acute effects of intermittent pneumatic foot versus calf versus simultaneous foot and calf compression on popliteal artery hemodynamics: a comparative study

INTRODUCTION

Intermittent pneumatic compression (IPC) is currently being investigated with respect to its effect on distal arterial volume flow in patients with peripheral vascular disease. Recently published data have shown a substantial acute enhancement in arterial calf inflow in response to IPC of the lower limb in both intermittent claudication and leg ischemia.

PURPOSE

The aim of the study was to compare the immediate effects of intermittent pneumatic foot (IPC(foot)) versus calf (IPC(calf)) versus simultaneous foot and calf compression (IPC(foot+calf)) on popliteal artery hemodynamics in patients with intermittent claudication (Fontaine II) and in normal subjects, using duplex ultrasonography. For this purpose, 25 limbs of 20 healthy subjects (age range [mean], 51-74 [64] years) and 31 limbs of 25 claudicants (age range [mean], 56-81 [66.5] years; resting ankle-brachial indices, 0.38-0.75 [0.55]) were examined in the sitting position with and without IPC compression.

RESULTS

Mean popliteal artery flow in healthy subjects increased by 98.8% on application of IPC(foot), 188% with IPC(calf), and 274% with IPC(foot+calf) (all P <.001). Mean flow in claudicants increased by 58% on application of IPC(foot), 132% with IPC(calf), and 174% with IPC(foot+calf) (all P <.001). The mean velocity, peak systolic velocity, and end diastolic velocity displayed a pattern of change similar to that for volume flow in both groups. Pulsatility index decreased in both groups on application of IPC; the lowest values were generated with IPC(foot+calf).

CONCLUSION

Of the three compression modes investigated, IPC(foot+calf) was the most effective means of acutely augmenting arterial calf inflow in arteriopaths and normals. The significant increase in end diastolic velocity and decrease in pulsatility index indicate that peripheral vasodilatation is the central mechanism in this impulse-related flow augmentation. Prospective trials are indicated to determine the clinical potential of the long-term effects of IPC(foot+calf) in patients with symptomatic peripheral vascular disease.

Superficial vein valve repair with a new external valve support (EVS). The IMES (International Multicenter EVS Study)

The aim of this international multicenter trial was to evaluate the effects of a new surgical device (Gore External Valve Support-EVS) and technique for external valvuloplasty of the long saphenous vein (LSV). Patients with superficial venous disease and venous hypertension due to pure superficial venous incompetence were randomized into two treatment groups, the first treated with "conventional treatment" (ligation or stripping) and the second with external valvuloplasty with the EVS. Patients with uncomplicated varicose veins within the age range of 35-65 years were included. Incompetence with presence of functional cusps at the saphenofemoral junction (SFJ), with vein dilatation were the main inclusion criteria. The EVS comprised of a GORE-TEX patch material (including a nitinol frame) that is placed around the vein, producing a reduction in the caliber of the vein. Also the vein section becomes elliptical. These combined actions are aimed to reduce incompetence, allowing a better closure of the cusps. The EVS was placed at the SFJ after limited dissection of the vein and ligation of collaterals. The procedure was randomized as an alternative to simple ligation or stripping (according with the procedure commonly used in the center). The associated ligation of distal incompetent veins was allowed. The main outcome measures of the study were evaluated by color-duplex (morphologic findings and evaluation of reflux) and with ambulatory venous pressure (AVP) or air-plethysmography (APG). Main endpoints of the first year of the study and main subject of this report (mainly concerning safety within the first year of follow-up) were considered presence/absence of reflux; patency of the veins; mobility/function of vein cusps; occurrence of thrombosis; tolerability of the device; and increased complexity and operating time needed for the EVS. At 1 year 30 patients had been randomized (14 EVS implanted, 16 controls). Reflux was absent in all EVS patients, all treated veins were patent, and all cusps were mobile. No thrombosis had been observed and the tolerability of the device was very good. The increased complexity required by placing the EVS was limited (5-12 minutes more). In conclusion results of the first year show efficacy and tolerability of the EVS. In selected patients (superficial LSV incompetence, reflux-dilatation, functional SFJ cusps, incompetence mainly due to enlargement of the vein), the EVS could be an effective alternative to "destructive" ligation and/or stripping of the vein. Prolonged follow-up will indicate the clinical potentials of the EVS.

Endovascular sclerotherapy, surgery, and surgery plus sclerotherapy in superficial venous incompetence: a randomized, 10-year follow-up trial--final results

The study was planned to evaluate efficacy and costs of endovascular sclerotherapy (ES) in comparison with surgery and surgery associated with sclerotherapy in a prospective (10-year follow-up), good-clinical-practice study. Patients with varicose veins and pure, superficial venous incompetence were included. Of the patients randomized into the three groups 39 (group A) were treated with ES, 40 (B) with surgery + sclerotherapy, and 42 with surgery only (C). Surgery consisted of ligation of the SFJ (saphenofemoral junction) and of incompetent veins detected with color duplex. Of the preselected 150 patients, 121 subjects entered the study; 96 completed the 10-year follow-up (mean age 52.6 +/- 6 years; 51 men, 45 women). Dropouts were due to nonmedical problems. At 10 years no incompetence was observed in subjects treated with SPJ ligation (B and C). In the ES group 18.8% of the SFJs were patent and incompetent and in 43.8% of limbs the distal (below-knee) venous system was still incompetent [16.1% in the surgery + sclerotherapy group (p < 0.05) and 36% in the group treated with surgery only (p < 0.05 vs B and 0.05 vs A)]. Color duplex of the long saphenous vein indicated atrophy or obstruction of a segment (average 6.7 cm) after SFJ ligation (4.2 cm after ES). The cost of ES was 68% of surgery while the cost of surgery and sclerotherapy was 122% of surgery only. Endovascular sclerotherapy is an effective, cheaper treatment option, but surgery after 10 years is superior.