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Biomedical subjects

A B Buchwald

Publications and source records attributed to A B Buchwald.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Successful lysis of iliofemoral and inferior vena cava thrombi in heparin-induced type-II thrombocytopenia].

HISTORY AND CLINICAL FINDINGS: After 10 days of intravenous heparin treatment of a 25-year-old woman with recurrent pulmonary emboli, thrombocytopenia occurred with a platelet drop from 1.52 x 10(5)/microliter to 3.6 x 10(4)/microliter. Heparin-induced platelet activation assays confirmed the diagnosis of heparin-induced thrombocytopenia (HIT). The detected heparin-dependent antibodies exhibited in vitro cross-reactivity with low-molecular-weight heparins, but not with danaparoid. TREATMENT AND COURSE: After heparin was stopped and platelet counts were normal, a massive thrombosis of the iliofemoral veins and the inferior vena cava occurred. Under protection of a temporary vena cava filter, systemic anticoagulation with danaparoid (anti-factor Xa-activity 0.4-0.8 U/ml) and transcatheter thrombolysis with urokinase (70,000 U/h) was initiated. Within 8 days of treatment a complete recanalisation of the occluded iliofemoral and caval veins was achieved. Oral anticoagulation with phenprocoumon was started and the patient has since then been free of symptoms. CONCLUSION: The case demonstrates successful treatment of massive iliofemoral and caval thrombosis in the HIT syndrome achieved by combined transcatheter administration of urokinase and systemic infusion of danaparoid.

Adult↗
PubMed1997

Single-laser approach for fluorescence guidance of excimer laser angioplasty at 308 nm: evaluation in vitro and during coronary angioplasty.

BACKGROUND AND OBJECTIVE: Spectroscopic guidance of laser angioplasty has been attempted using a diagnostic He-Cd laser in addition to the therapeutic laser system. This study evaluated a single-laser approach for simultaneous ablation and fluorescence excitation. STUDY DESIGN/MATERIALS AND METHODS: A spectroscopy system was coupled to a clinical XeCl excimer laser. Ablation of 162 human aortic samples in saline and blood with 45 mJ/mm2 per pulse yielded 676 fluorescence spectra validated histologically. The same equipment was used in 16 patients for angioplasty of 18 coronary stenoses applying 500 to 1,725 pulses with 45 to 60 mJ/mm2 under saline flushing. A total of 783 spectra were recorded and validated by intracoronary ultrasound (categories: atheroma, fibrous plaque, calcified lesion). RESULTS: In vitro, 5 types of spectra could be differentiated: (1) atheroma, (2) fibrous plaque, (3) calcified lesion in saline, (4) media, and (5) calcified lesion in blood. Discriminant analysis prospectively classified 576 validation spectra with the following sensitivity and specificity for each type: (1) 83.5 and 97.1%, (2) 85.7 and 96.8% (3) 100 and 98.5%, (4) 98.1 and 99.3%, (5) 98.9 and 100%, respectively. In vivo type 1, 2, 3, and 5 spectra were also observed, but not the media spectrum. The predominant sonographic category also prevailed in spectroscopy. Calcified lesions yielded type 3 and 5 as well as mixed spectra. CONCLUSIONS: Using an excimer laser for angioplasty allows combining ablation and fluorescence excitation without a diagnostic laser. Principal types of atherosclerotic lesions and the media can be differentiated spectroscopically with this approach.

Adult↗
PubMed1997

Expansion of Wiktor stents by oversizing versus high-pressure dilatation: a randomized, intracoronary ultrasound-controlled study.

Two strategies to achieve optimal expansion of Wiktor stents in coronary arteries, oversizing at normal balloon pressures (group 1) and high-pressure dilatation (group 2), were compared. We randomly assigned 20 symptomatic patients with de novo coronary artery stenoses of <15 mm length to one of the two treatment groups. Intracoronary ultrasound catheter pull-backs after stent implantation showed incomplete stent attachment with one or two struts protruding into the vessel lumen in 3 of 10 patients in group 1 but in no patient after high-pressure dilatation in group 2 (p<0.01). Recross and high-pressure dilatation of the 3 stents in group 1 achieved complete attachment of all stents. Minimal luminal diameter was comparable between the groups (2.61 +/- 0.34 mm in group 1 after stent delivery, and 2.68 +/- 0.45 mm in group 2 after high-pressure dilatation). Minimal luminal area (expressed as a percentage of the reference cross-sectional area) was slightly but insignificantly greater in the high-pressure group (91.1% +/- 25.6% vs 85.5% +/- 15.1%). We conclude that implantation of Wiktor stents at normal inflation pressures does not reliably result in complete attachment of all struts to the vessel wall.

Aged↗
PubMed1997

Additional luminal area gain by intravascular ultrasound guidance after coronary stent implantation with high inflation pressure.

AIMS: Studies by intravascular ultrasound demonstrated inadequate expansion in a large number of stents, which lead to the increase of inflation pressure for stenting. The present study examined whether routine use of high-pressure inflation would be sufficient for an optimum stent expansion without sonographic guidance. METHODS AND RESULTS: Two types of single coronary stents (Palmaz-Schatz in 54, and Wiktor in 25) were implanted with inflation pressures of 16-20 atm in 79 nonocclusive coronary lesions. IVUS before stenting was used in 78% to select the adequate stent size. Intravascular ultrasound after stenting was used to asses the minimum stent are and diameter, the reference areas, and the strut apposition to the vessel wall. The difference between the area of the expanding balloon and the stent area was calculated as the luminal deficit of the stent. Completeness of stent expansion required full strut apposition and lesion coverage, and a minimum stent area that was larger than the distal reference, and larger than 60% of the proximal reference. Intravascular ultrasound before stenting lead to an increase of the stent size in 47%. After high-pressure expansion, even with the optimized balloon size, 8% of stents had struts protruding into the lumen. The stent area (6.87 +/- 1.93 mm2) was significantly smaller than both the proximal (9.59 +/- 2.91 mm2; p < 0.001) and distal reference area (8.23 +/- 3.03 mm2; p < 0.001). The criteria for complete expansion were met in 48%. The expansion with a larger high-pressure balloon in 28 stents lead to an increase of the stent area by 19% (8.19 +/- 2.24; p < 0.001), and full stent apposition in all cases. The criteria of stent expansion were met in 82%. A wide range of the luminal deficit upto 48% was observed, which was not related to sonographic lesion characteristics, except in lesions with complete circumferential calcifications. The different stent designs were characterized by a slightly lower luminal deficit in slotted-tube stents (23 +/- 13% vs. 28 +/- 12%; p = 0.11) and a better index of stent symmetry as compared with the coil stent (0.87 +/- 0.08 vs. 0.82 +/- 0.09; p < 0.05). CONCLUSION: Routine use of high-pressure stent expansion did not lead to a sufficient stent expansion, even when the initial stent size had been guided by intravascular ultrasound. Further stent dilatation with larger balloons under ultrasound guidance would be required to optimize the luminal area gain.

Adult↗
PubMed1997

Morphology of chronic coronary occlusions and response to interventional therapy--a study by intracoronary ultrasound.

OBJECTIVES: Balloon angioplasty of chronic coronary occlusions has a low procedural success and a high recurrence rate. Better tomographic insights into the lesion morphology may improve the interventional strategy and results. METHODS: Intracoronary ultrasound was used during the recanalizaton procedure of 45 chronic coronary occlusions (2 weeks to 14 months; average 3.4 months) to determine the lesion morphology and to assess the angioplasty result. The luminal area and the plaque burden were measured proximal and distal to the occlusion, and within the occlusion. The ultrasonographic characteristics of the occlusive lesions were compared to 45 nonocclusive lesions of age-matched patients with stable angina pectoris. RESULTS: Occlusive lesions were more often echodense as compared to nonocclusive lesions (35% vs. 20%; p = 0.10). In chronic occlusions a multi-layered plaque morphology was observed in 22%, and this morphology was not found in nonocclusive lesions. Angiographic characteristics were not related to the ultrasonographic morphology of the lesion. Despite similar vessel areas in occlusive and nonocclusive lesions, the balloon size selected according to the angiographic image was underestimated in occlusive lesions. Based on the quantitative ultrasound measurement the balloon size was increased from 2.6 +/- 0.3 mm to 3.3 +/- 0.5 mm in 53% of the lesions. This resulted in an increase of the luminal area from 3.51 +/- 0.92 to 5.08 +/- 1.43 mm2 (p < 0.001). The acute recoil after balloon angioplasty was similar (34 +/- 18%) in hypodense and echodense plaques, but was significantly higher in lesions with a multi-layered plaque morphology (49 +/- 22%; p < 0.05). In 19 patients with severe dissections or extreme acute recoil (residual stenosis > 50%) the use of a stent increased the luminal area from 3.94 +/- 0.81 to 7.51 +/- 1.71 mm2 (p < 0.001). CONCLUSIONS: Intracoronary ultrasound demonstrated a multi-layered plaque morphology in one fourth of the chronic occlusions. This type of plaque was associated with a significant acute recoil. The presence of diffuse atherosclerosis in neighbouring segments of chronic coronary occlusions leads to underestimation of the balloon size. Quantitative assessment by intracoronary ultrasound helped to optimize the balloon size leading to a significant luminal area gain. The detection of excessive acute recoil should be considered an indication for stent deployment.

Angioplasty, Balloon, Coronary↗
PubMed1996

Inhibition of neointimal proliferation after coronary angioplasty by low-molecular-weight heparin (clivarine) and polyethyleneglycol-hirudin.

Proliferation of medial smooth muscle cells (SMC) plays a major role in restenosis after coronary angioplasty and can be inhibited by heparin. Platelets stimulate SMC proliferation, and their aggregation after angioplasty can be reduced by the direct thrombin inhibitor hirudin. In a porcine coronary stent-angioplasty model (16 animals, 4 per group), we studied the effect of 3- and 14-day treatment with a novel long-lasting polyethyleneglycol-conjugated (PEG-hirudin, LU 57291), at a dose of 1 mg/kg intravenously (i.v.) and then subcutaneously once daily as compared with chronic low-molecular-weight heparin (LMWH) clivarine at a dose of 150 IU/kg as an intravenous bolus, followed by 10 IU/kg/h i.v. for 24 h, followed by 75 IU/kg twice daily, as compared with acute unfractionated heparin (100 IU/kg) as a control. Sixteen animals were randomly assigned to the four treatment groups. Four weeks after angioplasty, hearts were perfusion-fixed and six slices per angioplasty segment were analyzed for neointimal thickness and neointimal area (% of total vessel cross-sectional area). Maximal neointimal thickness was 1.10 +/- 0.2 mm in the control group (mean +/- SD, n = 9 arteries) and was significantly lower in both PEG-hirudin (0.62 +/- 0.22 and 0.86 +/- 0.18 mm, 11 and 10 arteries) and in clivarine-treated animals (0.75 +/- 0.33 mm, 11 arteries, p < 0.01). Similarly, neointimal area was smaller in PEG-hirudin groups (20 +/- 12 and 21 +/- 12%) and in the clivarine group (24.8 +/- 13.2%) as compared with the control group (41 +/- 17%, p < 0.02). We conclude that PEG-hirudin and clivarine reduce neointimal proliferation in a coronary stent-angioplasty model. Prolonged PEG-hirudin has no better effect than therapy limited to 3 days.

Angioplasty, Balloon, Coronary↗
PubMed1996

Accumulation of unphosphorylated calponin in the submembranous cytoskeletons of arachidonic acid-stimulated human platelets.

Calponin, a basic smooth-muscle protein capable of binding to F-actin, tropomyosin and calmodulin in vitro, was tested for its expression and subcellular localization in resting and stimulated human platelets. Using immunoblotting techniques calponin was revealed as a single protein band with a molecular weight of 34 kDa. Although calponin has been shown to be proteolytically degraded by calpain, in the presence of the calpain inhibitor E-64 and EGTA a significant hydrolysis of calponin could not be detected. Upon stimulation with 10 microM arachidonic acid calponin became increasingly incorporated into Triton X-100 insoluble cytoskeletal fractions reaching a plateau after 15 s. The accumulation of calponin in the cytoskeletons of stimulated platelets paralleled the polymerization of actin into newly formed microfilaments. Immunofluorescence microscopy revealed a submembranous co-localization of calponin and actin in aggregated platelets. Since isolated calponin is phosphorylated by protein kinase C and Ca2+/calmodulin-dependent protein kinase II thereby losing its inhibitory effect on the actomyosin MgATPase activity, we examined whether changes in cell shape due to platelet stimulation are accompanied by a phosphorylation of calponin. By performing immunoblotting analysis on either resting or stimulated platelets phosphorylation of calponin on tyrosine, serine or threonine residues could not be demonstrated. In line, [32P]radiolabeling experiments were unable to detect phosphate incorporation into calponin. These observations support the hypothesis that calponin plays a physiological role in regulating contraction and secretion of human platelets even in the absence of its phosphorylation.

Actins↗
PubMed1995

Reduced acute thrombus formation results in decreased neointimal proliferation after coronary angioplasty.

OBJECTIVES: We tested the hypothesis that reduced acute platelet deposition after angioplasty results in reduced late neointimal proliferation. BACKGROUND: Platelet-mediated mechanisms contribute to smooth muscle cell proliferation and migration. METHODS: Indium-111-labeled platelets were injected 16 h before coronary stent angioplasty in 10 Göttinger minipigs: group 1 (n = 5) = heparin (100-U/kg bolus) before angioplasty; group 2 (n = 5) = recombinant hirudin (CGP 39393, 1.0-mg/kg body weight bolus intravenously), followed by subcutaneous doses of 6 to 10 mg/kg every 8 h. Furthermore, stent angioplasty was performed in coronary arteries of 16 minipigs: group 3 (n = 5, nine stents) = 100 U/kg heparin only; group 4 (n = 5, 10 stents) = 1-mg/kg bolus hirudin before and 45 min after angioplasty; group 5 (n = 6, 11 stents) = hirudin (1-mg/kg intravenous bolus) before and 45 min after angioplasty, followed by 6 to 10 mg/kg subcutaneously every 8 h. RESULTS: In segments with deep arterial injury, the number of platelets/angioplasty segment in group 2 after 72 h (mean 21, range 9.7 to 39.7 x 10(6)) was significantly less than that in group 1 (mean 375, range 72 to 787 x 10(6)). Morphometric analysis after 4 weeks showed no difference between groups in degree of vessel wall injury. Mean (+/- SD) neointimal thickness was 0.70 +/- 0.06 mm in group 3 and was significantly reduced in both group 4 (0.46 +/- 0.11 mm) and group 5 (0.48 +/- 0.21 mm). CONCLUSIONS: The direct thrombin inhibitor hirudin significantly reduces platelet deposition up to 72 h after coronary stent angioplasty. A hirudin bolus alone as well as continued subcutaneous administration for 14 days substantially reduced neointimal proliferation compared with heparin 4 weeks after coronary stent angioplasty in minipigs.

Angioplasty, Balloon, Coronary↗
PubMed1995

Effects of heparin on aortic versus venous smooth muscle cells: similar binding with different rates of [3H]thymidine incorporation.

The mechanisms resulting in the high incidence of stenoses of coronary venous bypass grafts are still unclear. Heparin, a potential inhibitor of cellular proliferation, neither inhibits intimal hyperplasia in animal models of vein-to-artery grafting nor prevents graft stenosis when administered to patients. We studied the effects of heparin on cultured pairs of human aortic and venous smooth muscle cells (SMC) obtained during coronary bypass surgery from patients with no history of previous restenosis or graft failure. DNA synthesis was measured as [3H]thymidine incorporation after stimulation with 10% fetal calf serum (FCS). Heparin (100 micrograms/ml) inhibited DNA synthesis of aortic SMC to 64 +/- 14% (mean +/- SEM), whereas it stimulated DNA synthesis of venous SMC to 136 +/- 23% (10% FCS alone = 100%; p = 0.01, Wilcoxon signed-rank test, n = 7). Binding studies with [3H]heparin showed no significant differences of Kd values and number of binding sites per cell between SMC derived from aorta or vein that could account for the lack of heparin inhibition of venous SMC DNA synthesis. These data suggest an inherent difference in the heparin susceptibility that may explain the failure of heparin to inhibit intimal proliferation in vein grafts.

Aorta↗
PubMed1994

Expression of meta-vinculin in human coronary arteriosclerosis is related to the histological grade of plaque formation.

In the present study we demonstrate that the quantitative reduction of meta-vinculin expression parallels histological changes during the course of coronary arteriosclerosis. Immunofluorescence stainings of coronary arteries revealed that vinculin distribution resembled that of other smooth muscle-specific cytoskeletal proteins like alpha-actin, caldesmon or myosin light chain kinase in labeling smooth muscle cells brightly. Although close to arteriosclerotic plaques, the cellularity as measured by the density of nuclei was often not significantly altered. Cells of this location expressed markedly reduced amounts of vinculin, suggesting that they are smooth muscle cells of a synthetic phenotype. To determine the fractional meta-vinculin content in arteriosclerotic lesions, we performed densitometric scanning of immunoblots incubated with anti-vinculin monoclonal antibodies reacting with both meta-vinculin (150 kDa) and vinculin (130 kDa). In parallel, each tissue sample was evaluated histologically for the degree of arteriosclerotic alterations according to the morphometric atheroma score of Stratford et al. (n = 13). In type 1 lesions covering slight intimal thickening, meta-vinculin represented 36% (mean, range 35%-39%) of the total vinculin immunoreactivity. In type 2 lesions consisting of fibrous plaques of up to twice the original artery wall thickness, meta-vinculin accounted for 28% (mean, range 22%-35%) of the total vinculin content. Meta-vinculin was substantially reduced in type 3 lesions (mean 13%, range 8%-18%) which are characterized by extensive atheromatous plaques. Thus, the meta-vinculin/vinculin ratio differed significantly between early, intermediate and advanced phases of coronary arteriosclerotic plaque formation.

Aged↗
PubMed1993

[Coronary angioplasty with controlled longitudinal dissection. Initial clinical results using a new cutting balloon].

A recently developed cutting balloon was used for coronary angioplasty in 21 patients (4 women, 17 men; mean age 57.6 [36-81] years) with coronary heart disease (angioplasty of the right coronary artery in 4, of the circumflex branch in 4, and of the anterior interventricular branch in 13 patients). The balloon contains 3-4 longitudinally arranged metal cutters to prevent uncontrolled vessel tears. An average stenosis reduction from 84 +/- 8.6% to 30 +/- 10.6% was achieved in ten patients. In the eleven others a second dilatation with a conventional balloon was necessary because of a residual stenosis of over 50% after the first dilatation with the cutting balloon. This reduced the original stenosis from 78.6 +/- 9.4% to 30.4 +/- 9.9%. Complete occlusion at the place of previous dilatation occurred in one patient 14 hours after the procedure, due to a dissection which required a stent implantation. These preliminary results suggest that the cutting balloon can achieve a stenosis reduction similar to that with a conventional balloon.

Adult↗
PubMed1993

Cutting balloon coronary angioplasty--initial clinical experience.

The success of percutaneous transluminal coronary angioplasty is limited by acute occlusion and late restenosis. In 25 patients (20 men, 5 women, age range 36-81 years) coronary angioplasty was performed using a new cutting balloon into which 3-4 longitudinally orientated blades are incorporated so as to reduce the rate of severe dissections. In 12 patients stenoses were reduced from 83.9 +/- 7.8% to 28.4 +/- 10.7% (mean +/- SD) by the cutting balloon alone, using predilatation with a small conventional balloon in two cases. Thirteen other patients were additionally dilated with a conventional balloon because of a residual stenosis > 50% after cutting balloon angioplasty. Here the stenoses could be reduced from 78.1 +/- 8.7% to 29.1 +/- 11.3%. Six months follow-up angiography in 14 patients showed > 50% restenosis in two of seven patients dilated with a conventional balloon in addition to the cutting balloon, and in one of seven patients dilated with the cutting balloon alone but predilated with a small conventional balloon. These results show that coronary angioplasty by the new cutting balloon results in a stenosis reduction comparable with conventional balloons at a low complication rate. Available 6 months follow-up data show three restenoses in patients either pre- or postdilated by a conventional balloon and none in stand-alone cutting balloon cases.

Adult↗
PubMed1993

Platelet and fibrin deposition on coronary stents in minipigs: effect of hirudin versus heparin.

OBJECTIVES: The present study was designed to test the hypothesis that the direct thrombin hirudin is more efficient than heparin in reducing thrombus formation after coronary stenting. BACKGROUND: Despite aggressive anticoagulation, subacute thrombosis of coronary stents is a major complication associated with these new devices. METHODS: In 19 minipigs indium-111-labeled thrombocytes and iodine-125-labeled fibrinogen were injected 14 to 19 h before coronary implantation of tantalum balloon-expandable stents. In group 1 (n = 6, seven stents), a bolus of heparin (100 U/kg body weight) was given before stenting. Group 2 (n = 6, 11 stents) received both dextran (500 ml) and heparin (a 100-U/kg bolus followed by a continuous infusion of 50 U/kg per h). In group 3 (n = 7, 13 stents), hirudin (recombinant desulphatohirudin HV 1 [CGP 39393] [1 mg/kg]) was given before stent implantation, followed by an infusion of 1 mg/kg per h. All animals were pretreated with aspirin (250 mg intravenously). RESULTS: Activated partial thromboplastin time was prolonged to > 1.8 times control values in groups 2 and 3. Histologic examination after perfusion fixation 12 h after stenting showed a variable extent of thrombus on all stents. Medial tear was observed in three stents in group 1, six stents in group 2 and six stents in group 3. The number of platelets on all stents averaged 116.2 (range 22 to 522) x 10(6) in group 1, 64.3 (range 11 to 169) x 10(6) in group 2 and 19.7 (range 9 to 38) x 10(6) in group 3 (p < 0.05 vs. group 1 and vs. group 2). The increase in platelet deposition, associated with medial tear in all groups, was lowest in the hirudin group. Similarly, fibrin deposition was lowest on stents in hirudin-treated animals. CONCLUSIONS: Recombinant hirudin significantly reduces platelet and fibrin deposition on coronary stents compared with the reduction achieved with combined heparin, dextran and aspirin.

Angioplasty, Balloon, Coronary↗
PubMed1992

Restenosis after excimer laser angioplasty of coronary stenoses and chronic total occlusions.

In an open clinical study, a xenon-chloride excimer laser was used for angioplasty of coronary stenoses (n = 48) and chronic total occlusions (n = 56) in 104 patients. Multifiber catheters (4.0F to 5.5F) transmitted 37 to 120 mjoules/mm2 of fiber surface. Excimer laser angioplasty was successful in 43 patients with a stenosis (89%), followed by percutaneous transluminal coronary angioplasty in 21 patients (49%) to reduce the stenosis to less than 50% luminal narrowing. In 39 patients (70%) with a chronic occlusion (age 1 to 14 months), recanalization by means of excimer laser angioplasty was successful, with subsequent percutaneous transluminal coronary angioplasty performed in 23 patients. Major complications included one perforation, one acute occlusion, and two severe dissections. Six-month angiographic follow-up examinations after successful angioplasty were completed in 40 patients (98%) with stenoses and 34 (94%) with occlusions. Restenosis (greater than 20% decrease in luminal diameter) occurred in 13 patients (33%) with stenoses and in 16 patients (47%) after angioplasty of a chronic occlusion. These long-term results indicate that restenosis after excimer laser angioplasty of coronary stenoses and chronic total occlusions is similar to reported results of conventional balloon angioplasty.

Angioplasty, Balloon↗
PubMed1992

Low-molecular-weight heparin reduces neointimal proliferation after coronary stent implantation in hypercholesterolemic minipigs.

BACKGROUND: Intracoronary stents have been suggested as a method of reducing the restenosis rate after balloon angioplasty. Proliferation of vascular smooth muscle cells is a major contributing factor to the restenosis process. Heparin and some of its derivatives have been shown to inhibit smooth muscle cell proliferation. We investigated the effect of low-molecular-weight heparin on the proliferative response after implantation of a balloon-expandable tantalum stent in previously deendothelialized coronary artery segments of hypercholesterolemic minipigs. METHODS AND RESULTS: Minipigs were fed a diet containing 2% cholesterol, starting 1 month before balloon denudation of the endothelium in a coronary artery. One month later, a stent was implanted at this site. Animals were killed after 4 weeks (group 1, n = 6) or 3 months (group 2, n = 6). Animals in group 3 (n = 6), also followed for 4 weeks after stenting, received subcutaneous low-molecular-weight heparin at a dose of 200-300 units/kg anti-factor Xa activity per day in addition to the chronic acetylsalicylic acid (100 mg/day) also administered to groups 1 and 2. Eighteen of 22 animals survived to the end of the study. Angiography revealed patent stents in all surviving animals. In group 1, histological analysis showed extensive neointimal proliferation around stent struts. Maximal neointimal thickness seen in group 1 averaged 0.93 +/- 0.11 mm, was lower after 3 months (0.8 +/- 0.14 mm) in group 2, but was significantly reduced (0.44 +/- 0.18 mm, p less than 0.01) in group 3. CONCLUSIONS: These data show a significant reduction of the neointimal proliferative response to coronary stent implantation by low-molecular-weight heparin.

Animals↗