Peripheral Artery Stenosis Research Articles

Cryoplasty for the Treatment of Femoropopliteal Arterial Disease: Results of a Prospective, Multicenter Registry

Despite suboptimal results, angioplasty of femoropopliteal arterial lesions has been a mainstay of endovascular therapy for many years. The recent introduction of cryoplasty marks a potential advance in the ability to effectively treat peripheral arterial atherosclerotic stenoses. This article presents the results of a prospective, multicenter trial that evaluated the efficacy of cryoplasty for femoropopliteal disease. One hundred two patients with claudication and lesions of the superficial femoral and popliteal arteries of no greater than 10 cm were studied. All patients were treated with a primary strategy of stand-alone cryoplasty with use of the PolarCath cryoplasty system. The primary endpoints of the study were acute technical success and clinical patency at 9 months. Technical success was defined as the ability to achieve residual angiographic stenosis no greater than 30% and residual stenosis less than 50% by duplex ultrasound (US) imaging. Clinical patency was defined as freedom from target lesion revascularization within 9 months. Primary patency was defined by a duplex US systolic velocity ratio no greater than 2.0. A total of 102 patients were enrolled at 16 centers. Of those treated, 31% had diabetes and 31% were active cigarette smokers. The majority of the lesions were confined to the superficial femoral artery (84.3%) and 14.7% presented with total occlusions. The mean vessel diameter treated was 5.5 mm +/- 0.5, the mean stenosis diameter was 87% +/- 10%, and the mean lesion length was 4.7 cm +/- 2.6. The technical success rate was 85.3% with a mean residual stenosis after cryoplasty of 11.2% +/- 11.2% (P < .05 vs baseline). Clinical patency in this group was 82.2%, as only 16 patients required target lesion revascularization during the 9-month surveillance period. Primary patency determined by duplex US was 70.1%. Cryoplasty demonstrated a high degree of acute angiographic success and a low frequency of target lesion revascularization. The patency rate observed compares favorably to that previously documented with conventional angioplasty.

Cilostazol Reduces Target Lesion Revascularization After Percutaneous Transluminal Angioplasty in the Femoropopliteal Artery

Although percutaneous transluminal angioplasty (PTA) is being widely used for the treatment of stenosis of peripheral arteries, the high in-stent restenosis rate (50-60%) in the femoropopliteal artery still remains an unsolved issue. Cilostazol is a unique antiplatelet drug that has vasodilatory effects and inhibits smooth muscle cell proliferation. A total of 141 consecutive patients scheduled for PTA in the femoropopliteal artery between September 1999 and April 2004 were retrospectively analyzed for the use of cilostazol. Target lesion revascularization (TLR) was defined as repeated PTA in patients who had a recurrence of symptoms with diameter stenosis >50% by angiography. Patient and lesion characteristics were similar between the cilostazol (+) and cilostazol (-) groups. Use of other medications was similar between the groups, except for ticlopidine, which was more frequently used in the cilostazol (-) than in the cilostazol (+) group (15% vs 61%, p<0.01). TLR was significantly reduced in the cilostazol (+) group (12% [8/68] vs 32% [23/73], p<0.01). Although this study was retrospective and nonrandomized, the results suggest that cilostazol reduces TLR after PTA in the femoropopliteal artery.

Using 6-mm Cutting Balloon Angioplasty in Patients with Resistant Peripheral Artery Stenosis: Preliminary Results

The objective of this study was to assess the efficacy of 6-mm Cutting Balloon angioplasty in patients with resistant peripheral stenoses caused by neointimal hyperplasia or irradiation-induced arteriopathy in vascular territories that are not amenable for use of the smaller Cutting Balloons that are used in cardiology. Peripheral Cutting Balloon angioplasty with the new 6-mm Cutting Balloon device proved useful in the short term for treatment of peripheral arterial stenoses resistant to conventional angioplasty.

A New Guidewire Technique for Difficult Cardiac Catheterization

Purpose: To propose a simple guidewire technique to resolve the problem of difficulty in advancing catheters or guidewires during vascular and cardiac catheterization. Methods: A 0.035-inch J-tip guidewire was reshaped manually at the distal 7- to 8-cm portion, including the flexible part and 2–3 cm of the stiff part, into zigzag shape. With this modification, the guidewire became much more trackable and could be advanced to the right position. Results: In the past 2 years, this ‘zigzag wire technique’ was applied in cardiac catheterization with high success rates for cases with difficulty in advancing either catheters or guidewires. This wire technique was applied in peripheral arterial tortuosity or stenosis (18 cases, with success in 17), aortic aneurysm (successful in all 7 cases), aortic stenosis (11 cases, successful in 8), and dilated right heart chambers (successful in all 6 cases). No complications resulted from the use of this guidewire technique. Conclusion: This simple method of guidewire modification would be very helpful in difficult vascular and cardiac catheterization when difficulty in advancing catheters or wires was encountered.

Bovine hemoglobin (HBOC-201) restores tissue oxygen tension during peripheral and coronary artery stenosis under extended hemodilution.

Bovine hemoglobin (HBOC-201) restores tissue oxygen tension during peripheral and coronary artery stenosis under extended hemodilution.

Cardiovascular News

Cardiovascular News

Radiofrequency thermal balloon angioplasty in an experimental model of peripheral arterial stenosis

Rationale: To assess the effect of thermal balloon angioplasty on surgically created peripheral arterial stenoses. Methods: Unilateral femoral arterial stenoses were created in 17 neonatal lambs (Dorset×Suffolk/Mule), using absorbable sutures. Six to 8 weeks later, the stenoses were dilated using either a standard ( N=5), or thermal balloon angioplasty ( N=9). Immediate angiography, flow and pressure gradient measurements were made to assess the acute result following either procedure. The survivors were followed up for a further period of 4 to 6 weeks, and a terminal angiographic study performed. The thermally treated segments of vessels were removed for qualitative histologic analysis. Results: Thermal angioplasty appeared to be acutely successful in eight of nine animals, compared with one of five successful procedures following standard angioplasty. Higher therapeutic temperatures (≥80°C) were associated with vascular complications. At the terminal study, stenoses had recurred in four of six survivors successfully treated with thermal angioplasty. Histologic studies demonstrated non-uniform effects of thermal dilation on the vessel wall, with variable changes ranging from partial or full-thickness tears, fibroblastic or myocyte proliferation, and disorganization of the vessel wall layers. Conclusion: Thermal angioplasty appears to be acutely more beneficial compared with standard angioplasty. However there is a significant recurrence of stenoses, and non-uniform changes in the vessel wall.

Effect of hemodynamic conditions on sonographic measurements of peak systolic velocity and arterial diameter in patients with peripheral arterial stenosis

Effect of hemodynamic conditions on sonographic measurements of peak systolic velocity and arterial diameter in patients with peripheral arterial stenosis

Drug-eluting PTA Balloon Dilatation Catheter in the Treatment of Peripheral Artery Stenosis or Occlusion

Drug-eluting PTA Balloon Dilatation Catheter in the Treatment of Peripheral Artery Stenosis or Occlusion

Detection of distal emboli in patients with peripheral arterial stenosis before and after iliac angioplasty: A prospective study

Purpose: Embolism is believed to be the major cause of end-organ damage after angioplasty and endoluminal procedures. Recently, Doppler ultrasound scanning has been used to detect asymptomatic cerebral emboli. We determined whether asymptomatic embolic signals (ES) could be detected distal to a significant iliac artery stenosis of >60% both before and soon after iliac percutaneous transluminal angioplasty (PTA). Methods: A 2-MHz Doppler scan probe was used to monitor for ES in the common femoral artery before and after 10 successful iliac artery PTAs and at various standardized times in the following 24 hours. The same protocol was used to study 10 patients in the control group after renal PTA. In addition, a single recording was performed in a second nonoperative control group of 10 patients who had no evidence of peripheral vascular disease. The Doppler scan signals were recorded on tape for a later blinded analysis. Results: In the 24 hours before iliac PTA, asymptomatic ES were detected in four of 10 patients during a 1-hour recording but in no controls ( P = .025). After iliac PTA, ES were detected at 30 minutes in nine of 10 iliac subjects but in only one of 10 renal subjects ( P = .0003) and at 2 hours in eight of 10 iliac subjects but in only one of 10 renal subjects ( P = .001). The occurrence of ES became less frequent, and ES were present at a lower frequency in eight of 10 iliac PTA subjects at 4 hours and in five of 10 at 24 hours but in no renal PTA subjects at these time points. Conclusions: ES can be detected in the common femoral artery with Doppler ultrasound scanning in patients with iliac artery stenosis both before and soon after iliac PTA despite preangioplasty aspirin and intra-angioplasty heparin therapies. The occurrences of ES were particularly frequent in the 2 hours after PTA. This technique can be used further to study factors that control plaque stability and to evaluate the effect of therapeutic interventions. (J Vasc Surg 1999;29:345-51.)

Frequency of Combined Atherosclerotic Disease of the Coronary, Periphery, and Carotid Arteries Found by Angiography

Background:The real incidence of atherosclerotic lesions in carotid and peripheral arteries in coronary artery disease patients is not well known in Korea. The aim of this study was to prospectively evaluate the prevalence of atherosclerotic involvement of the coronary, carotid, and peripheral arteries in each arterial disease patients. This study was also designed to evaluate the risk factors, the clinical characteristics of associated carotid artery stenosis in patients with coronary artery disease, and associated peripheral vascular disease in patients with coronary artery disease. Methods:Between June 1996 and March 1998, 475 patients (369 males, 106 females, mean age 60±10 years) were studied. Three hundred and seventy-three patients who presented with ischemic symptoms were enrolled in the coronary artery disease group, 81 patients were enrolled in the peripheral vascular disease group due to presenting claudications, and 21 patients were enrolled in the carotid stenosis group due to presenting cerebrovascular symptoms. Coronary angiography was done by the routine method. Carotid angiography was performed at the aortic arch by the digital subtraction angiography method. Peripheral vascular angiography was taken from the suprarenal abdominal aorta to both femoral arteries. Results:1) Risk factors for coronary stenosis, peripheral vascular disease, and carotid stenosis:The risk factors were not different between coronary stenosis, peripheral vascular disease, and carotid stenosis groups, but smoking was more frequent among patients with peripheral vascular disease than in patients with coronary stenosis (p-value=0.001). 2) Coronary artery stenosis and carotid artery stenosis:The mean age of coronary artery patients with carotid stenosis was significantly older (p-value=0.006) than for patients without carotid stenosis. The prevalence of peripheral vascular disease was more common in patients with carotid stenosis than in patients without carotid stenosis. 3) Coronary artery stenosis and peripheral vascular disease:Carotid stenosis was more common inpatients with peripheral vascular disease than in patients without peripheral vascular disease in the coronary stenosis group. 4) Prevalence of coronary, carotid, and peripheral artery disease:In patients with coronary stenosis, the prevalence of carotid stenosis was 13.9% and that of peripheral vascular disease was 29.2%. In patients with peripheral artery stenosis, the prevalence of coronary stenosis was 45.7% and that of carotid artery disease was 33.3%. In patients with carotid stenosis, the prevalence of coronary stenosis was 81.0% and that of peripheral 논문접수일:1999년 5월 6일 심사완료일:1999년 9 월 1일 교신저자:신원흠, 120-752 서울 서대문구 신촌동 연세대학교 의과대학 심혈관센터 심장내과학교실 전화:(02) 361-7049·전송:(02) 393-2041 E-mail:whshimyumc.yonsei.ac.kr

Alteraciones cardiovasculares en el síndrome de cutis laxa congénita

Cutis laxa is a unusual disorder of the connective tissue. It may be hereditary or acquired and from the genetical viewpoint, can be either of the dominant or of the recessive type. The autosomic dominant type, less frequent, has a late beginning and the evolution is usually benign, and it seldom has cardiovascular anomalies. On the contrary, the recessive type usually has an early beginning having frequent cardiovascular anomalies, with the outcome of death early in infancy. We report two siblings with the recessive type of the illness, having peripheral arterial stenosis of pulmonary branches. We review the literature with special attention to the angiohemodynamic findings, as there are few bibliographic reports about this subject, as well as about the different hypothesis on the pathogenesis of this illness.

Limitations of Percutaneous Treatment for Peripheral Arterial Vein Graft Stenoses

Peripheral arterial bypass vein graft stenosis is the leading cause of graft failure within the first 2 years following implantation. These lesions are generally secondary to myointimal hyperplasia and have historically been treated with graft revision or operative patch angioplasty. Unfortunately, graft revision or angioplasty requires reoperation through a scarred incision and usage of additional portions of autologous conduit. The purpose of this study is to assess the effectiveness of percutaneous transluminal angioplasty (PTA) in the treatment of vein graft stenosis. PTA was performed in 17 patent vein grafts in 16 patients for the treatment of perianastomotic and/or midvein graft stenoses occurring 7 ± 1 months (range 0.5-18 months) after graft implantation. Criteria for follow-up and patency adhered to the standards of the Ad Hoc Committee on Reporting Standards of the SVS/NAISCVS. After a mean follow-up of 17 ±3 months (range 2-44 months), the procedure-specific 18-month primary patency, primary-assisted patency, secondary patency, and limb salvage rates were 48 + 17%, 63 + 12%, 67 ± 12%, and 78 ± 15%, respectively. Subgroup analysis revealed favorable lesions (one or two focal lesions, &lt; 1 cm length) in 11 grafts. Life-table analysis for this subgroup revealed primary patency, primary-assisted patency, secondary patency, and limb salvage rates of 68 ±20%, 90 ±9%, 90 ±9%, and 100%, respectively. The overall results of PTA for vein graft stenosis are poor and PTA should not be liberally applied to complex lesions. PTA may be a reasonable alternative to operative repair for focal vein graft stenoses in high-risk patients or in patients with limited remaining autologous conduit.

Contrast-enhanced 3D MRA with centric ordering in k space: a preliminary clinical experience in imaging the abdominal aorta and renal and peripheral arterial vasculature.

The objective of this study was to determine the clinical utility of a contrast-enhanced, centric reordered, three-dimensional (3D) MR angiography (MRA) pulse sequence in imaging the abdominal aorta and renal and peripheral lower extremity arteries. Twenty-eight MRA studies were performed on 23 patients and four volunteers at 1.5 T using a 3D contrast-enhanced, centric reordered pulse sequence. In 20 patients, the abdominal aorta and renal arteries were imaged, and in seven patients, the lower extremity arteries were imaged. In 19 patients, a total of 51 renal vessels were evaluated (33 renal arteries using .1 mmol/kg of gadopentetate dimeglumine and 18 renal arteries using .2 mmol/kg of gadoteridol). A total of 70 peripheral arterial segments were assessed using .2 mmol/kg of gadoteridol. Correlation with conventional angiography was made for the following 14 cases: renal artery stenosis (four cases), abdominal aortic stenosis (one case), arteriovenous fistula in a transplant kidney (one case), renal arteriovenous malformation (one case), common iliac artery aneurysms (one case), and peripheral lower extremity (six cases). Of the 70 peripheral arterial segments evaluated, in 35, there was correlation with x-ray angiography. The mean percent of aortic signal enhancement was significantly higher in the .2 mmol/kg dose group (370.8 +/- 190.3) than in the .1 mmol/kg dose group (184.5 +/- 128.9) (P = .02). However, there was no apparent difference between the two doses for visualization of the renal and accessory renal arteries. There was concordance between the contrast-enhanced 3D MRA studies and conventional angiography in all cases of renal artery and peripheral arterial stenoses and occlusions, including visualization of reconstituted peripheral arterial segments. There was no evidence of spin dephasing effects at sites of stenoses on the 3D contrast-enhanced MRA studies. Contrast-enhanced, centric reordered, 3D MRA can rapidly image the abdominal aorta and renal and accessory renal arteries, as well as peripheral lower extremity arteries, with high resolution. Accurate depiction of the vascular lumen at sites of stenosis is made because of the lack of spin dephasing effects, even with hemodynamically significant stenoses. Additional larger clinical trials are required with this promising technique.

Is plaque formation in the common carotid artery representative for plaque formation and luminal stenosis in other atherosclerotic peripheral arteries? A post mortem study

The atherosclerotic carotid artery is easily accessible for non-invasive duplex investigation. The aim of the present post mortem study was to examine whether plaque accumulation and luminal stenosis in the common carotid artery is representative for atherosclerotic plaque accumulation and luminal stenosis in other peripheral arteries. A total of 3765 cross-sections were obtained at regular intervals from 240 arteries (24 individuals). Five types of peripheral arteries were investigated: common carotid, femoral, common iliac, external iliac and renal arteries. In each cross-section, the lumen area, vessel area, plaque area and maximal plaque thickness was measured. For each location, the percentage luminal stenosis and relative plaque area was calculated. Relative plaque area was defined as the percentage of the vessel area which was occupied by plaque. Weak correlations ( r=0.41–0.59) were observed between percentage relative plaque area or maximal plaque thickness in the common carotid artery and percentage relative plaque area in other peripheral arteries. Neither plaque accumulation nor luminal stenosis in the common carotid artery correlated with the percentage luminal stenosis in other peripheral arteries ( P>0.05). We conclude that plaque area in the common carotid artery is weakly correlated with plaque area and not correlated with luminal stenosis in other peripheral arteries.

Multiple Arterial Injuries and Prolonged Cholesterol Feeding Do Not Increase Percent Lumen Stenosis: Impact of Compensatory Enlargement in the Microswine Model

While the swine model is frequently utilized in the study of arterial intervention, it has been difficult to create severe peripheral arterial stenosis without total thrombotic occlusion with a single arterial injury and short-term cholesterol feeding. The combination of multiple arterial injuries and prolonged cholesterol feeding was explored in an effort to create lesions with significant luminal compromise. Nineteen microswine were divided into two groups and fed a high cholesterol diet followed by multiple balloon injuries of the iliac arteries. We conclude that repeated balloon injuries and longer cholesterol feeding significantly increase areas of plaque and necrotic core but do not increase percent stenosis because of arterial compensatory enlargement. The microswine iliac arteries enlarge in relation to plaque area and repeated balloon injuries. The compensatory lumen enlargement may be one of the factors resulting in significant angiographic underestimation of plaque area during the early stage of the atherosclerotic disease, but it may functionally delay important lumen stenosis until the lesion occupies 40% of the internal elastic lamina area. This study suggests that repeated injury and longer cholesterol feeding to increase percent stenosis may not be cost effective in this model. However, this model is good for studying an increase in plaque accumulation.

Myocardial Revascularization with a Free Skeletal Muscle Flap

Based on encouraging experimental evidence, a new myocardial revascularization procedure was, for the first time, used on a sixty-six-year-old patient. This patient suffered from unstable angina (NYHA class III-IV). He had diffuse peripheral coronary artery stenosis (three-vessel disease). Bicycle ergometry showed ischemic ST segment changes at 25 W. After two myocardial infarctions, his prognosis for life was very bad. Therefore, he underwent this new surgery. After a median sternotomy, a free latissimus dorsi muscle flap was grafted onto the anterior wall of the heart. The flap artery was anastomosed end-to-side to the aorta, and venous flow was directed into the right atrium. The graft was fixed with sutures to the epicardium and pericardium. The chest was then closed. The patient had two anginal episodes on the third and fourth postoperative days. Up to the present, these were his last anginal attacks. Eight weeks postoperatively a bicycle ergometry evinced no signs of ischemia at 120 W. Angiographically, a fine vascular network originating from the graft had penetrated into the heart. Four months later, he was able to perform a 10 km walk in one day. Eight months later, he went back to work. His quality of life was 100% improved, although dyspnea on exertion still persists. Up to the present, a year and a half after the intervention, he has had no more anginal episodes. Thus, myocardial revascularization can be achieved with this new aortomyocardial bypass.

Mechanical factors in restenosis; hemodynamic studies in humans

Atherectomy is a new therapeutic intervention for the treatment of peripheral arterial disease, and permits the controlled excision and retrieval of portions of stenosing lesions. The gross and light microscopic features of 218 peripheral arterial stenoses resected from 100 patients by atherectomy were studied. One hundred seventy of these lesions were primary stenoses and 48 were restenoses subsequent to prior angioplasty or atherectomy. Microscopically, primary stenoses were composed of atherosclerotic plaque (150 lesions), fibrous intimai thickening (15 lesions) or thrombus alone (5 lesions). Atherosclerotic plaques had a variable morphology and, in one-third of cases, were accompanied by abundant surface thrombus that probably added to the severity of stenosis. Most patients with fibrous intimai thickening or thrombus alone had typical atherosclerotic plaque removed elsewhere from within the same artery.Intimai hyperplasia, with or without underlying residual plaque, was found at 36 sites of restenosis, the remaining 12 consisting of plaque only. Intimai hyperplasia had a distinctive histologic appearance and was due to smooth muscle cell proliferation within a loosely fibrous stroma. Superimposed thrombus may have contributed to arterial narrowing in 25% of hyperplastic and 8% of atherosclerotic restenoses (p = 0.41). Pathologic examination of tissues recovered by peripheral atherectomy is an important adjunct that may provide insight into the efficacy of vascular interventions and the phenomenon of postintervention restenosis.

The role of wall smear stress in bestinotic and anastamotic inimal hyperflasia

Atherectomy is a new therapeutic intervention for the treatment of peripheral arterial disease, and permits the controlled excision and retrieval of portions of stenosing lesions. The gross and light microscopic features of 218 peripheral arterial stenoses resected from 100 patients by atherectomy were studied. One hundred seventy of these lesions were primary stenoses and 48 were restenoses subsequent to prior angioplasty or atherectomy. Microscopically, primary stenoses were composed of atherosclerotic plaque (150 lesions), fibrous intimai thickening (15 lesions) or thrombus alone (5 lesions). Atherosclerotic plaques had a variable morphology and, in one-third of cases, were accompanied by abundant surface thrombus that probably added to the severity of stenosis. Most patients with fibrous intimai thickening or thrombus alone had typical atherosclerotic plaque removed elsewhere from within the same artery.Intimai hyperplasia, with or without underlying residual plaque, was found at 36 sites of restenosis, the remaining 12 consisting of plaque only. Intimai hyperplasia had a distinctive histologic appearance and was due to smooth muscle cell proliferation within a loosely fibrous stroma. Superimposed thrombus may have contributed to arterial narrowing in 25% of hyperplastic and 8% of atherosclerotic restenoses (p = 0.41). Pathologic examination of tissues recovered by peripheral atherectomy is an important adjunct that may provide insight into the efficacy of vascular interventions and the phenomenon of postintervention restenosis.

Treatment of Anastomotic Bypass Graft Stenosis with Directional Atherectomy: Short-term and Intermediate-term Results

Areas of anastomotic stenosis in lower-extremity bypass grafts (BPGs) were treated by means of directional atherectomy (DA) in hopes of achieving better patency rates than have been reported with percutaneous transluminal angioplasty (PTA). During a 4-year period, 17 patients (11 men and six women) with 23 areas of anastomotic stenosis in 18 lower-extremity BPGs were selected for treatment with DA. Urokinase thrombolysis was initially performed in eight BPGs that were thrombosed at the time of presentation. Adjunctive preatherectomy PTA was performed in six lesions, and postatherectomy PTA was performed in three lesions. The technical success rate for DA was 92% (23 of 25 sites). There was less than 50% restenosis at 74% of the areas of stenosis (14 of 19 sites), with a mean follow-up time for the sites of 13 months. The graft patency rate was 88% (14 of 16 grafts), with a mean follow-up time for the grafts of 14 months. Areas of stenosis treated with DA alone had the same patency rates as those treated with DA and PTA. DA is an effective treatment method for anastomotic peripheral arterial BPG stenosis. The intermediate-term patency rates following DA are superior to those reported for PTA and similar to those reported for surgical revision.