Retrograde Femoral Artery Stent-Graft Implantation for Treatment of Access-site Bleeding Following Transcatheter Aortic Valve Implantation.

BACKGROUND: Access-site bleeding is a common complication of transfemoral transcatheter aortic valve implantation (TAVI). Percutaneous stent-graft implantation within the femoral artery may achieve hemostasis and avert the need for more invasive surgical vascular repair; however, failure to advance a guidewire antegradely via the injured vessel may preclude stent delivery. While retrograde stent-graft delivery from the distal vasculature may potentially enable percutaneous control of bleeding, this approach has not been reported. OBJECTIVES: To assess the feasibility of a retrograde approach for stent-graft implantation in the treatment of access-site bleeding following transfemoral TAVI. METHODS: A prospective TAVI registry was analyzed. Of 349 patients who underwent TAVI, transfemoral access was used in 332 (95%). Access-site injury requiring stent-graft implantation occurred in 56 (17%). In four patients (7%), antegrade wiring across the site of vascular injury was not possible and a retrograde approach for stent delivery was used. RESULTS: Distal vascular access was achieved via the superficial femoral or profunda artery. Retrograde advancement of a polymer-coated 0.035" wire to the abdominal aorta, followed by stent-graft delivery to the common femoral artery, achieved hemostasis in all cases. During a median (interquartile range) follow-up period of 198 (618) days (range 46-2455) there were no deaths and no patient required additional vascular interventions. CONCLUSIONS: A retrograde approach for stent-graft delivery is feasible and allows percutaneous treatment of a common femoral artery injury following TAVI in patients who are not suitable for the conventional antegrade approach.

Endarterectomy or Stenting in Severe Asymptomatic Carotid Stenosis.

BACKGROUND: Stroke is a major cause of death in the western world, and carotid endarterectomy has been shown to be effective in treating both symptomatic and asymptomatic carotid stenosis. Carotid stenting is a relatively new form of treatment for carotid stenosis and few studies have looked specifically at asymptomatic patients. OBJECTIVES: To retrospectively examine short- and long-term results in the treatment of asymptomatic carotid artery stenosis with surgery or stenting. METHODS: We retrospectively collected data of all patients with asymptomatic carotid stenosis treated by carotid artery stenting or carotid endarterectomy in our department from 2006-2007. The primary endpoints were stroke, myocardial infarction, or death during the periprocedural period; or any ipsilateral stroke, restenosis, or death within 4 years after the procedure. RESULTS: The study comprised 409 patients who were treated by either stenting or surgery. There was a low morbidity rate in both treatment groups with no significant difference in morbidity or mortality between the treatment groups in both in the short-term as well as long-term. CONCLUSIONS: Both treatment methods have a low morbidity and mortality rate and should be considered for patients with few risk factors and a long life expectancy. Treatment method should be selected according to the patient's individual risk factors and imaging data.

Expression of lipoprotein-associated phospholipase A(2) in carotid artery plaques predicts long-term cardiac outcome.

AIMS: The aim was to test the hypothesis that carotid artery plaque expression of lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) predicts cardiac events. METHODS AND RESULTS: Prospective cohort study of 162 consecutive patients undergoing elective carotid endarterectomy. Lipoprotein-associated phospholipase A(2) content was quantified by immunoblotting and lysophosphatidylcholine (lysoPC) by liquid chromatography tandem mass spectrometry. Additional biomolecular profiling by immunoblotting included C-reactive protein, p67phox, and matrix metalloproteinase-2 and -9. Macrophage plaque content was determined by quantitative immunostaining, plaque collagen content by quantitative Sirius red staining. Follow-up for cardiac death and non-fatal acute myocardial infarction was accomplished over a period of 48 +/- 14 months. Expression of Lp-PLA(2) and lysoPC was higher in carotid plaques of patients with than without cardiac events [median 1.6 (25th, 75th percentile 0.9, 2.5) vs. 0.8 (0.5, 2.0), P = 0.01 and 413 (281, 443) vs. 226 (96, 351) mmol/L, P = 0.03]. Smoking and point increase in carotid Lp-PLA(2) expression but no other traditional cardiovascular risk factor, histological or molecular marker remained predictive of cardiac events in the multivariate Cox proportional hazard analyses [HR 3.65 (1.36-9.83), P = 0.01 and HR 1.34 (1.01-1.77), P = 0.039]. Carotid plaque Lp-PLA(2) expression above the median constituted a more than three times higher risk for cardiac events [HR 3.39 (1.13-10.17), P = 0.03]. CONCLUSION: Lipoprotein-associated phospholipase A(2) expression in carotid artery plaques is a predictor of long-term cardiac outcome. The current study supports the concept of atherosclerosis as a systemic disease with multi-focal complications and personalized medicine.

Prevention of vasa vasorum neovascularization attenuates early neointima formation in experimental hypercholesterolemia.

Vasa vasorum (VV) neovascularization is a key feature of early atherosclerosis and adds substantial endothelial exchange-surface to the coronary vessel wall. Thus, it is conceivable that VV neovascularization favors the entry of pro-inflammatory and pro-atherosclerotic blood components into the coronary vessel wall. We sought to investigate the effects of Thalidomide (Th), a potent anti-angiogenic drug on vasa vasorum (VV) neovascularization, vessel wall inflammation, and neointima formation in early experimental atherosclerosis. Female domestic swine, 3 months old, were fed normal (N, n = 12) or high-cholesterol diet (HC, n = 12) for 3 months. In each group six pigs were randomized to 200 mg Thalidomide daily for the diet period (N + Th, HC + Th). LADs were scanned with micro-CT (20 microm cubic voxel size) to determine VV spatial density (#/mm2). Fresh-frozen coronary tissue was used for western blotting (VEGF, TNF-alpha, LOX-1, Ikappabetaalpha and Gro-alpha) and electrophoretic mobility shift assay (EMSA, NFkappabeta). Treatment with Thalidomide preserved VV spatial density [2.7 +/- 0.3 (N), 6.4 +/- 0.7 (HC), 3.5 +/- 0.8 (HC + Th); p = ns HC + Th vs. N] and inhibited the expression of VEGF, TNF-alpha and LOX-1, but not NFkappabeta activity in the coronary vessel wall. Immunofluorescence analyses revealed co-localization of vWF but not SMA and NFkappabeta, TNF-alpha as well as VEGF in HC and HC + Th coronaries. Intima-media thickness was significantly inhibited in HC + Th compared to HC. Serum levels of hs-CRP and TNF-alpha did not differ among the groups. Our study supports a role of VV neovascularization in the development of and a therapeutic potential for anti-angiogenic intervention in early atherosclerosis.

Enhanced expression of Lp-PLA2 and lysophosphatidylcholine in symptomatic carotid atherosclerotic plaques.

BACKGROUND AND PURPOSE: Circulating lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) has emerged as a novel biomarker for cardiovascular diseases. However, the correlation between the plaque expression of Lp-PLA(2) and plaque oxidative stress, inflammation, and stability as well as the clinical presentation remains poorly defined, especially for cerebrovascular disease. Therefore, this study was performed to test the hypothesis that Lp-PLA(2) expression is higher in symptomatic than in asymptomatic carotid plaques of patients undergoing carotid endarterectomy. METHODS: The expression of Lp-PLA(2) in 167 carotid artery plaques was determined by immunoblotting and immunostaining. Plaque oxidative stress, inflammation, and stability were quantified by NAD(P)H oxidase p67phox and MMP-2 immunoblotting, oxidized LDL (oxLDL) immunoreactivity, macrophage and Sirius red collagen staining. Lysophosphatidylcholine 16:0 (lysoPC) concentration was measured in 55 plaques using liquid chromatography tandem mass spectrometry. RESULTS: Lp-PLA(2) expression was significantly higher in plaques of symptomatic patients than asymptomatic patients (1.66+/-0.19 versus 1.14+/-0.10, P<0.05) and localized mainly to shoulder and necrotic lipid core areas in colocalization with oxLDL and macrophage content. Similarly, Lp-PLA(2) expression was related to collagen content, which was lower in plaques from symptomatic patients than in plaques from asymptomatic patients (9.1+/-2.2 versus 18.5+/-1.7% of staining/field, P<0.001). LysoPC plaque concentration was significantly higher in plaques of symptomatic than asymptomatic patients (437.0+/-57.91 versus 228.84+/-37.00 mmol/L, P<0.05). CONCLUSIONS: Symptomatic carotid artery plaques are characterized by increased levels of Lp-PLA(2) and its product lysoPC in correlation with markers of tissue oxidative stress, inflammation, and instability. These findings strongly support a role for Lp-PLA2 in the pathophysiology and clinical presentation of cerebrovascular disease.

Increased spatial vasa vasorum density in the proximal LAD in hypercholesterolemia--implications for vulnerable plaque-development.

OBJECTIVE: Vasa vasorum (VV) neovascularization is associated with advanced and ruptured atherosclerotic lesions that occur predominantly within the proximal third of the LAD. To investigate further the possible role of VV spatial distribution in determining this predominantly proximal location of complex lesions we analyzed the changes in VV spatial densities along the LAD in early atherosclerosis. METHODS AND RESULTS: Three-month-old, female domestic pigs were placed on normal (N; n=6) or high-cholesterol (HC; n=6) diet for 3 months. VV count, vascular-area-fraction (Sigma vasa vasorum areas/mm(2) vessel wall area, i.e., flow capacity), and the endothelial-surface-fraction (Sigma vasa vasorum endothelial surfaces/mm(3) vessel wall volume) were calculated in three equal thirds of the coronary artery from microcomputed-tomography images. In N animals, the proximal thirds tended to have a higher vascular-area-fraction (mean+/-S.D., 1.4+/-0.6 versus 0.9+/-0.3 and 0.9+/-0.2%; P=0.1) and endothelial-surface-fraction (0.72+/-0.29 versus 0.59+/-0.22 and 0.53+/-0.20 mm(2)/mm(3); NS) than the mid and distal thirds with significantly higher VV counts (26+/-12, 15+/-8, 8+/-5, P=0.01). In HC animals, we observed significant VV neovascularization (3.3+/-1.2 n/mm(2) versus 6.8+/-1.9 n/mm(2), P<0.01), with significantly higher VV counts (24+/-3 and 14+/-3 versus 6+/-4; P<0.001) as well as higher vascular-area- (1.4+/-0.2 and 1.4+/-0.2% versus 0.8+/-0.2%; P<0.001) and endothelial-surface-fractions (0.88+/-0.14 and 0.90+/-0.12 mm(2)/mm(3) versus 0.56+/-0.14 mm(2)/mm(3); P=0.001) within the proximal and middle thirds compared to the distal third. CONCLUSIONS: VV neovascularization in early atherosclerosis leads to a proximally accentuated increase in flow-capacity and endothelial-exchange-surface, which may favour the predominant development of vulnerable atherosclerotic plaques in proximal portions of the LAD.

Vulnerable plaque: detection and management.

Because most myocardial infarctions result from the rupture of a plaque that did not significantly compromise the coronary lumen before the event, experts widely accept that the morphology, composition, and degree of inflammation of a coronary atherosclerotic plaque is more important than the degree of luminal stenosis. Two depicting examples are the concentric, calcified lesion that shows significant luminal stenosis but is stable because of the stabilizing clasp of calcification. In contrast, a smaller but inflamed thin fibrous cap atheroma with a big lipid/necrotic core may rupture and cause an immediate fatal coronary occlusion.

Dysregulation of the ubiquitin-proteasome system in human carotid atherosclerosis.

OBJECTIVE: The ubiquitin-proteasome system is the principal degradation route of intracellular and oxidized proteins, thus regulating many cellular processes conceivably important for atherosclerosis. The aim of this study was to evaluate the activity of ubiquitin-proteasome system in human carotid artery plaques in relation to oxidative stress and clinical manifestation. METHODS AND RESULTS: In carotid endarterectomy specimens from 83 asymptomatic and 94 symptomatic patients, content of ubiquitin, ubiquitin conjugates, matrix metalloproteases, and NADPH-oxidase-p67 was evaluated by immunoblotting; proteolytic proteasome activity by fluorometric assay; single and double immunostaining for ubiquitin conjugates, 3-nitrotyrosine, apoptosis, smooth muscle alpha-actin, and macrophage CD-68, as well as Sirius Red staining for collagen were performed. Compared with asymptomatic patients, symptomatic patients showed a more unstable plaque phenotype, an increased degree of apoptosis, a significantly higher ubiquitin conjugates content (17.72+/-1.36 versus 10.99+/-1.04; P<0.001), and lower proteasome activity (5.01+/-0.70 versus 9.41+/-1.19 nmol AMC/mg protein/min; P<0.01). Ubiquitin conjugates content was directly correlated to NADPH-p67 and degree of apoptosis. Immunostaining revealed colocalization of ubiquitin conjugates and 3-nitrotyrosine, and accumulation of ubiquitin conjugates in smooth muscle cells and macrophages. CONCLUSIONS: In human carotid plaques increased oxidative stress is associated with inhibition of the proteasome activity and accumulation of ubiquitin conjugates, particularly in symptomatic patients. These results suggest a possible role of the ubiquitin-proteasome system in influencing plaque stability.

A prospective randomized trial comparing endarterectomy to stenting in severe asymptomatic carotid stenosis.

BACKGROUND: For an asymptomatic patient with severe carotid stenosis the most important question is how to prevent an ischemic stroke. Carotid artery stenosis is the estimated cause of stroke in 8-20% of the cases. Today more than 50% of procedures for carotid stenosis are done on asymptomatic patients, but few of the randomized controlled trials comparing carotid endarterectomy and stenting examined specifically these patients. METHODS: All patients with severe (>70%) asymptomatic carotid artery stenosis seen in the Carmel medical center vascular clinic were prospectively screened and randomized 1:1 for carotid endarterectomy (CEA) or carotid stenting (CAS). Patients eligible for both procedures were enrolled. The primary objectives of the study were: 1) periprocedural complications - stroke (CVA), transient ischemic attack (TIA), myocardial infarction (MI), and death; 2) long-term results: mortality, prevention of ipsilateral stroke or TIA, and freedom from restenosis. RESULTS: One-hundred and thirty-six patients were treated with mean follow-up of 26 months. There was no difference in short and long term results between the two groups. Thirty day morbidity included: 1 CVA in each group with no MI. Long-term results included 4 deaths in each group; none from CVA. One TIA was noted after CAS, and 3 cases of restenosis were found in CEA and one in CAS. CONCLUSIONS: CAS is a maturing procedure and has improved significantly over the past several years. Future developments of stents and protection devices will achieve better perioperative results. This along with our excellent long term results will promote the use of stenting for suitable patients.

Endotoxemia inhibits intestinal adaptation in a rat model of short bowel syndrome.

Sepsis is commonly associated with or complicates short bowel syndrome (SBS). The purpose of the present study was to investigate the effects of endotoxemia on intestinal adaptation in a rat model of SBS. Male Sprague-Dawley rats were divided into three experimental groups: Sham rats underwent bowel transection and re-anastomosis, SBS rats underwent 75% small bowel resection, and SBS-LPS rats underwent bowel resection and were given lipopolysaccharide. Bowel weight, organ weights, and parameters of intestinal adaptation (bowel and mucosal weights, mucosal DNA and protein, villus height, and crypt depth) were determined on day 15 following operation. The results of this study demonstrate that SBS rats showed a significant increase (vs. Sham) in jejunal and ileal bowel and mucosal weight, mucosal DNA and protein, villus height, and crypt depth. SBS-LPS animals demonstrated lower (vs. SBS rats) final body weight (215 +/- 7 vs. 287 +/- 10 g, P < 0.05), overall weight in duodenum (98+/- 2 vs. 119 +/-5 mg/cm, P < 0.05) and jejunum (144 +/- 9 vs. 189 +/- 16 mg/cm, P < 0.05), mucosal weight in jejunum (54 +/- 5 vs. 69 +/- 5 mg/cm, P < 0.05) and ileum (31 +/- 2 vs. 37 +/- 3 mg/cm, P < 0.05), mucosal DNA in jejunum (89 +/- 11 vs. 120 +/- 11 microg/cm, P < 0.05) and ileum (46 +/- 6 vs. 61 +/- 4 microg/cm, P < 0.05), jejunal crypt depth (152 +/- 19 vs. 189 +/- 12 microm, P < 0.05), and ileal villus height (405 +/- 63 vs. 515 +/- 30 pm, P < 0.05). In addition, the SBS group had no late (second week) mortality, whereas the SBS-LPS group had an 17% late mortality rate. In conclusion, in a rat model of SBS-LPS, endotoxemia appears to inhibit structural intestinal adaptation and increase mortality.

Simvastatin preserves diastolic function in experimental hypercholesterolemia independently of its lipid lowering effect.

OBJECTIVE: Isolated diastolic dysfunction is present in 40% of heart failure patients. It has been attributed to myocardial fibrosis and related to cardiovascular risk factor exposure. We hypothesized that simvastatin will improve these dynamics in experimental hypercholesterolemia (HC). METHODS: Three groups of pigs were studied after 12 weeks of normal (N) diet, HC diet, or HC diet with simvastatin (80 mg/day) treatment. Cardiac function was assessed by electron beam computed tomography (EBCT) and percentage of myocardium occupied by microvessels (myocardial vascular fraction) was calculated by micro-CT. Collagen content was determined by Sirius red staining and confirmed by a quantitative, hydroxyoproline-based assay. RESULTS: Compared with N, LDL serum concentration was higher in HC and HC+simvastatin (1.0±0.1 vs. 7.9±1.7 and 9.6±1.2 mmol/L, p<0.05 for both). Cardiac early diastolic filling was reduced in HC compared with N (102.4±11.3 vs. 151.1±12.1 mL/s; p<0.05) but restored in HC+simvastatin (176.8±21.3 mL/s, p<0.05 vs. HC). Compared with N, myocardial vascular fraction was higher in HC but not in HC+simvastatin (1.98±0.84 vs. 4.48±0.31 and 2.95±0.95%; p<0.05 for HC vs. N). Myocardial collagen content was higher in HC than in HC+simvastatin and N (4.72±1.03 vs. 1.62±0.12 and 1.21±0.24% area staining; p<0.05 for HC vs. N), which was attributable mainly to an increase in collagen III (2.90±0.48 vs. 1.62±0.12 and 1.21±0.24% area staining; p<0.05 for HC vs. N). CONCLUSIONS: Simvastatin is able to prevent diastolic dysfunction in experimental HC independent of its lipid lowering effect. This beneficial effect is, at least partially, due to a decrease in myocardial fibrosis and angiogenesis.

Differential distribution of vasa vasorum in different vascular beds in humans.

OBJECTIVE: Vasa vasorum (VV) have been implicated to play a role in the pathogenesis of atherosclerosis. This study was designed to describe the distribution of VV density in different vascular beds in humans and to investigate the association between VV density and the known distribution of atherosclerosis in human arteries. METHODS: Forty-two human arteries, harvested at autopsy or after explantation, were analyzed by three-dimensional microscopic-computed tomography (micro-CT). VV density, endothelial-surface-fraction (Sigma VV endothelial-surface-area/vessel-wall-volume) and vascular-area-fraction (Sigma VV area/vessel-wall-area) were calculated for coronary, renal and femoral arteries. Representatively five coronary, renal and femoral arteries were stained for endothelial cells (von Willebrand-Factor), macrophages (CD68), vascular endothelial growth factor (VEGF) and collagen (Sirius Red). RESULTS: Coronary arteries showed a higher VV density compared to renal and femoral arteries (2.12+/-0.26 n/mm(2) versus 0.61+/-0.06 n/mm(2) and 0.66+/-0.11 n/mm(2); P<0.05 for both) as well as a higher endothelial-surface-fraction and vascular-area-fraction. Histology showed a positive correlation between histologically derived VV density and CD68-positive cells/area (r=0.54, P<0.01), VEGF-immunoreactivity/area (r=0.55, P<0.01) and a negative correlation between VV density and collagen I content (r=0.66, P<0.05). CONCLUSION: This micro-CT study highlights a higher VV density in coronary than in peripheral arteries, supporting the relation between VV density and the susceptibility to atherosclerosis in different vascular beds in humans.

Hypertension and hypercholesterolemia differentially affect the function and structure of pig carotid artery.

The purpose of this work was to compare the effects of hypertension and hypercholesterolemia on carotid endothelial function, structure, and vasa vasorum density. Seventeen pigs were randomized to a 12-week normal diet without (n=5), or with renovascular hypertension (HT; n=6), or to a high cholesterol diet (HC; n=6). Carotid arteries were studied by organ chambers (endothelial function) and microcomputed tomography (vasa vasorum), and tissue was processed for Sirius red staining and immunoblotting (vascular endothelium growth factor, endostatin, matrix metalloproteinase-9, and matrix metalloproteinase-2). HC and HT showed reduced vasodilation to acetylcholine as compared with controls, but HT also had a lower response to sodium nitroprusside. In addition, HT showed a higher content of organized collagen fibers and increased intima-media thickness. Vasa vasorum density was increased in HC but not in HT. Both HT and HC showed a proangiogenetic biochemical milieu (higher vascular endothelium growth factor, matrix metalloproteinases, and lower endostatin), but this was more pronounced in HC. Both hypertension and hypercholesterolemia induce endothelial dysfunction in the carotid artery. However, hypertension is also associated with greater fibrosis and vascular wall thickening, which might impair endothelium-independent vasorelaxation and vasa vasorum growth. Hypercholesterolemia is, in turn, associated with vasa vasorum neovascularization. These data suggest that carotid atherosclerosis can evolve through different mechanisms in relation to different risk factors.

Early experimental obesity is associated with coronary endothelial dysfunction and oxidative stress.

Obesity is independently associated with increased cardiovascular risk. However, since established obesity clusters with various cardiovascular risk factors, configuring the metabolic syndrome, the early effects of obesity on vascular function are still poorly understood. The current study was designed to evaluate the effect of early obesity on coronary endothelial function in a new animal model of swine obesity. As to method, juvenile domestic crossbred pigs were randomized to either high-fat/high-calorie diet (HF) or normal chow diet for 12 wk. Coronary microvascular permeability and abdominal wall fat were determined by using electron beam computerized tomography. Epicardial endothelial function and oxidative stress were measured in vitro. Systemic oxidative stress, renin-angiotensin activity, leptin levels, and parameters of insulin sensitivity were evaluated. As a result, HF pigs were characterized by abdominal obesity, hypertension, and elevated plasma lysophosphatidylcholine and leptin in the presence of increased insulin sensitivity. Coronary endothelium-dependent vasorelaxation was reduced in HF pigs and myocardial microvascular permeability increased compared with those values in normal pigs. Systemic redox status in HF pigs was similar to that in normal pigs, whereas the coronary endothelium demonstrated higher content of superoxide anions, nitrotyrosine, and NADPH-oxidase subunits, indicating increased tissue oxidative stress. In conclusion, the current study shows that early obesity is characterized by increased vascular oxidative stress and endothelial dysfunction in association with increased levels of leptin and before the development of insulin resistance and systemic oxidative stress. Vascular dysfunction is therefore an early manifestation of obesity and might contribute to the increased cardiovascular risk, independently of insulin resistance.

Impaired myocardial perfusion reserve in experimental hypercholesterolemia is independent of myocardial neovascularization.

Our objective was to investigate the functional role of hypercholesterolemia-associated myocardial neovascularization in early atherosclerosis using the antiangiogenic thalidomide. Experimental atherosclerosis is characterized by myocardial neovascularization, associated with a decrease in myocardial perfusion response to challenge, coronary endothelial dysfunction, and high oxidative stress. However, the functional significance of these neovessels is not known. Three groups of pigs (n = 6 each) were studied after 12 wk of normal or hypercholesterolemic diet without (HC) or with thalidomide (HC + Thal). Myocardial perfusion and permeability were assessed at baseline and in response to cardiac challenge, using electron beam computed tomography, and coronary endothelial function was assessed using organ chambers. Myocardial samples were scanned ex vivo with a three-dimensional microscopic computed tomography scanner, and the spatial density of the myocardial microvessels was quantified. Growth factors and oxidative stress were measured in the myocardial tissue. As a results of these procedures, myocardial perfusion response to adenosine and dobutamine was blunted in both HC and HC + Thal pigs compared with normal pigs (P < 0.05, HC and HC + Thal vs. normal) as was the coronary endothelial function. Myocardial permeability response to adenosine was increased in both HC and HC + Thal pigs compared with normal pigs (P < 0.05, HC and HC + Thal vs. normal, and HC + Thal vs. HC). The microvascular density was increased in HC pigs compared with normal pigs but normalized in HC + Thal pigs (P < 0.001 HC vs. normal and HC + Thal). HC + Thal pigs showed decreased expression of Flk-1 and basic FGF but increased expression of VEGF compared with normal and HC pigs. Oxidative stress was increased in both HC and HC + Thal pigs compared with normal pigs. In conclusion, chronic administration of thalidomide attenuates myocardial neovascularization in experimental HC pigs without affecting myocardial perfusion response to stimulation. This suggests that the myocardial neovascularization may not contribute to the attenuated myocardial perfusion response in hypercholesterolemia.

Carotid endarterectomy with a polyurethane patch versus primary closure: a prospective randomized study.

INTRODUCTION: The use of synthetic patch angioplasty during carotid endarterectomy (CEA) has been advocated to reduce restenosis, stroke, and death, but the type of material used is still being debated. This study compared rate of restenosis, neurologic events, and perioperative death in patients undergoing CEA with primary closure versus polyester urethane patch closure. PATIENTS AND METHODS: In a prospective randomized study, we compared patch angioplasty with polyester urethane (Vascular-patch, B. Braun Medical AG, Tuttlingen, Germany) to primary closure between February 1999 and March 2002 in 404 operations. Early (30-day) stroke and mortality rate, long-term restenosis, and neurologic events were compared in the two groups during 2.5 to 5 years of follow-up (median follow-up, 2 years). RESULTS: Primary closure was used in 216 operations, and patch angioplasty was used in 206. Clamping time was significantly shorter in the primary closure group ( P < .001). Perioperative mortality and neurologic events were similar in both groups (1.9% vs 3.9%, P = .21, odds ratio [OR], 2.1; 95% confidence interval [CI], 0.56 to 9.85). The rate of residual stenosis (> or =50%) at 0 or 3-month follow-up was significantly lower in the patch group (2 operations, 1.1%) compared with the primary closure group (17 operations, 8.9%) ( P = .001, OR, 0.114; 95% CI, 0.026 to 0.5). Multivariable logistic regression showed that only primacy closure was found to influence residual stenosis. Restenosis of 70% was significantly less in the patch angioplasty group (2.2% vs 8.6%) ( P = . 01, hazard ratio, 0.246; 95% CI, 0.08 to 0.75). No correlation was found between restenosis and gender, preoperative symptoms, or risk factors. CONCLUSIONS: Patch angioplasty with polyester urethane significantly reduced the restenosis rate ( P = . 01) compared with primary closure. Even though clamping time was longer, patching was not associated with more perioperative complications.