Lower expression of neutrophil adhesion molecule indicates less vessel wall injury and might explain lower restenosis rate after cutting balloon angioplasty

In stent restenosis: bane of the stent era

The long term outcome of stent implantation is affected by a process called in stent restenosis (ISR). Multiple contributory factors have been identified, but clear understanding of the overall underlying mechanism remains an enigma. ISR progresses through several different phases and involves numerous cellular and molecular constituents. Platelets and macrophages play a central role via vascular smooth muscle cell migration and proliferation in the intima to produce neointimal hyperplasia, which is pathognomic of ISR. Increased extracellular matrix formation appears to form the bulk of the neointimal hyperplasia tissue. Emerging evidence of the role of inflammatory cytokines and suppressors of cytokine signalling make this an exciting and novel field of antirestenosis research. Activation of Akt pathway triggered by mechanical stretch may also be a contributory factor to ISR formation. Prevention of ISR appears to be a multipronged attack as no therapeutic "magic bullet" exists to block all the processes in one go.

Cutting balloons for the treatment of vascular stenoses

The aim of this article is to review the mechanism, technical characteristics, biological response and clinical applications of cutting balloon angioplasty in peripheral vessels. The cutting balloon is a non-compliant, balloon catheter equipped with three-to-four microtome-sharp atherotomes. When used appropriately, it is safe and easy to use, with a high immediate success rate and few complications, provided oversizing is avoided. There is some evidence that pre-dilation with a standard or high-pressure balloon may also predispose to vascular rupture. The cutting balloon has proved to be beneficial in treating difficult complex lesions in the coronary arteries. Early experience in non-coronary vessels shows that cutting balloon angioplasty can be used to treat peripheral bypass anastomotic and haemodialysis fistula stenoses that are resistant to conventional high-inflation pressures. Its application in de novo peripheral arterial lesions and non-coronary in-stent restenosis is still under discussion. Theoretically, this device induces a smaller degree of vessel wall injury localised to the area of incisions and sparing the interincisional segments; however, this postulated reduction in restenosis rates has not been confirmed in clinical practice.

Pulmonary vein stenosis: initial experience with cutting balloon angioplasty

OBJECTIVE

To determine the safety and effectiveness of cutting balloon angioplasty for pulmonary vein stenosis (PVS).

DESIGN AND SETTING

Retrospective review of case notes and cardiac catheterisation data at the Royal Brompton Hospital.

MAIN OUTCOME MEASURES

Diameter of pulmonary vein, tricuspid regurgitant jet velocity on echocardiogram, and percutaneous oxygen saturation before and after cutting balloon angioplasty.

RESULTS

Three patients had congenital PVS and three had PVS associated with total anomalous pulmonary venous drainage. A total of 27 PVSs were treated during 12 catheterisation procedures. Median patient age at the time of procedure was 12.5 months (range 1.5-36 months) and weight was 7.1 kg (range 2.8-11.1 kg). Minimum pulmonary vein diameter increased significantly on angiography after cutting balloon angioplasty, from mean (SD) 2.3 (0.7) mm to 4.2 (1.9) mm, mean of differences 1.9 mm (95% confidence interval (CI) 0.9 to 2.9 mm, p = 0.0013). Mean (SD) oxygen saturation rose from 79.6 (12.9)% to 83.9 (9.0)%, mean of differences 4.3% (95% CI 0.7% to 8.0%, p = 0.0238). All children's symptoms improved subjectively. Tricuspid regurgitant jet velocity did not change significantly. The longest time interval before repeat intervention was six months. There were no acute deaths; one patient had a small pulmonary haemorrhage and developed a small aneurysm adjacent to the site of angioplasty.

CONCLUSION

Cutting balloon angioplasty is safe in the palliation of PVS in children. It gives some acute relief but often needs to be repeated, as improvement is rarely sustained.

Cutting Balloon: Review on Principles and Background of Use in Peripheral Arteries

This review describes peripheral use of cutting balloon (CB) angioplasty (CBA), its characteristics, and its distinction from conventional BA and describes the experimental and clinical background of its current use in peripheral arteries.

Local Release of C-Reactive Protein From Vulnerable Plaque or Coronary Arterial Wall Injured by Stenting

OBJECTIVES

The purpose of this study was to assess local release of C-reactive protein (CRP) from atherosclerotic plaques or the vessel wall injured by stenting.

BACKGROUND

Recent research has focused on the local production of CRP, especially in inflammatory atherosclerotic plaques.

METHODS

The study consisted of two separate protocols. In protocol 1, we measured serum high-sensitivity-CRP (hs-CRP) levels in coronary arterial blood sampled just distal and proximal to the culprit lesions in 36 patients with stable angina and 13 patients with unstable angina. In protocol 2, we measured serial serum hs-CRP levels and activated Mac-1 on the surface of neutrophils in both coronary sinus and peripheral blood in 20 patients undergoing coronary stenting.

RESULTS

In protocol 1, CRP was higher in distal blood than proximal blood in both stable (p < 0.05) and unstable angina (p < 0.01). The translesional CRP gradient (distal CRP minus proximal CRP, p < 0.05) as well as the proximal CRP (p < 0.05) and distal CRP (p < 0.05) was higher in unstable angina than in stable angina. In protocol 2, the transcardiac CRP gradient (coronary sinus minus peripheral blood) and activated Mac-1 increased gradually after stenting, reaching a maximum at 48 h (p < 0.001 vs. baseline for both). There was a positive correlation between the transcardiac CRP gradient and activated Mac-1 at 48 h (r = 0.45, p < 0.01).

CONCLUSIONS

C-reactive protein is an excellent marker for plaque instability or poststent inflammatory status, and its source might be the inflammation site of the plaque or the coronary arterial wall injured by stenting.

Intracoronary 166Holmium brachytherapy combined with cutting balloon angioplasty for the treatment of in-stent restenosis

BACKGROUND

Brachytherapy is the only effective treatment for in-stent restenosis (ISR). The preliminary data regarding cutting balloon angioplasty (CBA) are encouraging and suggest a possible additive effect of CBA with combination with vascular brachytherapy. Hence, in this study, we evaluated the efficacy, feasibility and safety of cutting balloon angioplasty followed by intracoronary Holmium (166Ho) brachytherapy for the treatment of in-stent restenosis.

METHODS AND MATERIALS

Fifty-six patients with in-stent restenosis were treated with cutting balloon angioplasty and intracoronary 166Ho brachytherapy. For irradiation, a balloon approximately 10 mm longer than the initially deployed stent was filled with liquid 166Ho and placed at the in-stent restenosis lesion. The patients were followed angiographically at 6 months and clinically for 19.0+/-9.8 months.

RESULTS

The initial procedures were successful in all of the patients. The preprocedural average minimal luminal diameter (MLD) and stenosis rate were 0.57+/-0.30 mm and 80.2+/-11.6%, respectively. The MLD and residual stenosis immediately after the procedure was 2.43+/-0.37 and 13.8+/-9.9%, respectively. Thirty-nine (69.6%) patients have completed their angiographic follow-up at 6 months. The MLD, late loss and loss index at follow-up were 1.97+/-0.79 mm, 0.72+/-0.69 mm and 0.36+/-0.34, respectively. The target lesion restenosis rate was 20.5% and the target lesion revascularization rate was 3.6%. None of these patients presented with adverse coronary events such as MI, sudden cardiac death or stent thrombosis during the follow up period.

CONCLUSION

The combination therapy using cutting balloon angioplasty and intracoronary 166Ho brachytherapy may be an effective new treatment modality for in-stent restenosis.

Cutting balloon angioplasty is superior to balloon angioplasty or stent implantation for small coronary artery disease

The aim of this study is to demonstrate initial results and long-term outcomes of patients after receiving cutting balloon angioplasty (CBA), balloon angioplasty (BA), or stenting for small vessel diseases. We studied a total of 327 lesions of small coronary disease treated either by CBA (n=87), BA (n=130), or stenting (n=110) in two affiliated institutes. A small coronary artery was defined as a reference vessel <2.5 mm using quantitative coronary angiography (QCA). Angiographic restenosis was encountered in 31% of the CBA, 46.5% of the BA, and 43.9% of the stent (p=0.048). Major adverse cardiac events (death, myocardial infarction, and target lesion revascularization) at follow-up were significantly lower in the CBA compared to other groups (CBA, 20.3%; BA, 37.3%; stent, 33.3%; p=0.036). The CBA procedure provided superior angiographic and clinical outcomes to the stenting or BA. The CBA may be a cost-effective and reasonable approach for the treatment of lesions in small coronary diseases.

Cilostazol inhibits leukocyte integrin Mac-1, leading to a potential reduction in restenosis after coronary stent implantation

OBJECTIVES

The aim of this study was to confirm clinically a hypothesis that cilostazol inhibits leukocyte Mac-1, leading to prevention of post-stent restenosis.

BACKGROUND

The platelet phosphodiesterase III inhibitor called cilostazol also inhibits alpha-granule release of P-selectin in platelets. The P-selectin-mediated platelet-leukocyte interaction promotes activation and upregulation of leukocyte Mac-1 after coronary stenting, which plays a key role on the mechanism of restenosis. Thus, cilostazol's potential inhibition of this process may lead to prevention of restenosis.

METHODS

Using flow cytometric analysis of whole blood obtained from the coronary sinus, the expression of platelet membrane glycoproteins and neutrophil adhesion molecules was observed in 70 consecutive patients undergoing coronary stenting. The patients were randomly assigned to either a cilostazol or ticlopidine group before stent placement.

RESULTS

The restenosis rate was lower (15% vs. 31%, p < 0.05) in the cilostazol group (n = 34) than in the ticlopidine group (n = 32). A stent-induced increase in platelet P-selectin (CD62P) expression and an increase in neutrophil Mac-1 (CD11b) expression were suppressed in the cilostazol group compared with the ticlopidine group. Angiographic late lumen loss was correlated with the relative changes in platelet P-selectin and neutrophil Mac-1 at 48 h after coronary stenting.

CONCLUSIONS

Cilostazol may have effects on suppression of P-selectin-mediated platelet activation, platelet-leukocyte interaction, and subsequent Mac-1-mediated leukocyte activation, which might lead to a reduced restenosis rate after coronary stent implantation.

Hemostatic and fibrinolytic activation is less following cutting balloon angioplasty of the coronary arteries

Recent studies have shown that percutaneous coronary intervention (PCI) activates systemic hemostatic activity, reflecting platelet activation and thrombin formation in the coronary arteries. The present study compared systemic levels of hemostatic markers induced by plain old balloon angioplasty (POBA), coronary stenting (STENT), and cutting balloon (CB) angioplasty. Sixty-one patients with stable angina pectoris, who underwent elective PCI or diagnostic coronary angiography (CAG) alone, were investigated. Patients who underwent PCI were divided into the POBA group (n = 11), the STENT group (n = 27), and the CB group (n = 11). Patients who underwent CAG alone were assigned to the CAG group (n = 12). Blood samples were collected before, 24 hours after, and 3 days after PCI or CAG. Plasma concentrations of prothrombin fragment 1+2 (F1+2), fibrinopeptide A (FPA), thrombin-antithrombin III complex (TAT), and plasminogen activator inhibitor-1 (PAI-1) were measured. In the CB group, the F1+2 (1.23 +/- 0.4 nmol/L) level 3 days after PCI was significantly smaller than that of the POBA group (2.37 +/- 0.5 nmol/L) (P < 0.05). The FPA (1.81 +/- 0.9 ng/mL), TAT (3.36 +/- 1.2 ng/mL) and PAI-1 (23.0 +/- 4.1 ng/mL) levels in the CB group 3 days after PCI were significantly smaller than those of the POBA group (P < 0.05, respectively) and STENT group (P < 0.05, respectively), but similar to the CAG group. Systemic hemostasis is activated to a greater extent after POBA and stenting than it is after CB angioplasty of the coronary arteries. This may contribute to the favorable long-term outcome of CB angioplasty.

Influence of ionic and non-ionic radiographic contrast media on leukocyte adhesion molecules

BACKGROUND: Many papers have focused on the importance of granulocytes in the process of reperfusion and ischemia. Most of the clinical studies measured several parameters of this process during and after coronary angiography, without taking into account the effect of the radiographic contrast media (RCM) used during this procedure. MATERIALS AND METHODS: We performed a randomized patient study (n = 37) to evaluate the effect of ionic and non-ionic RCM on granulocyte adhesion during coronary angiography. We also evaluated the influence of the ionicity and osmolarity of the different substances on granulocyte adhesion molecules in in vitro experiments. RESULTS: The osmolarity of patient serum samples increased from 302 +/- 1 to 309 +/- 1 mOsm/kg (p < 0.05) after infusion of RCM. The CD11b expression in the samples of the non-ionic RCM treated group increased from 221 +/- 21 MFI to 377 +/- 30 MFI (p < 0.05) measured as the absolute mean fluorescence intensity (MFI), yet did not alter significantly in the ionic RCM group. In contrast, the in vitro experiments showed a reduction of the CD11b expression from 360 +/- 70 MFI to 149 +/- 30 MFI (p < 0.05) in the ionic RCM group. CONCLUSIONS: The upregulation of adhesion molecules was significantly reduced in vivo with ionic RCM, while ionic substances caused opposite effects in vitro. This effect should be taken into account when performing leukocyte functional analysis of samples taken during angiography.

Promising efficacy of primary gradual and prolonged balloon angioplasty in small coronary arteries: a randomized comparison with cutting balloon angioplasty and conventional balloon angioplasty

BACKGROUND

Small vessel size represents a critical risk factor for an adverse outcome after both conventional balloon angioplasty (POBA) and stenting. Gradual and prolonged balloon angioplasty (GPBA) has been shown to cause less arterial trauma, which results in higher procedural success rates and fewer in-hospital complications than POBA. The aim of this study was to assess the clinical and angiographic benefits of primary GPBA with a perfusion balloon in small coronary arteries, as compared with cutting balloon angioplasty (CBA) and POBA.

METHODS

A total of 263 patients with symptoms and reference diameters <3.0 mm were randomly assigned to undergo GPBA (n = 85), CBA (n = 88), or POBA (n = 90). The cumulative inflation time must be >10 minutes in GPBA. Crossover to stent was allowed for inadequate results. Follow-up angiography was performed after 6 months. The primary end point was angiographic restenosis at follow-up.

RESULTS

Compared with POBA, GPBA resulted in a lower final residual diameter stenosis (27.3% vs 34.2%, P =.01) and decreased the need for stent placement (8.0% vs 22.2%, P =.031). At follow-up, the restenosis rates were lower with GPBA (31.3%, P =.034) and CBA (32.9%, P =.059) than POBA (50.6%). Target lesion revascularization was less frequently needed with GPBA (20.5%, P =.043) and CBA (20.0%, P =.033) than POBA (37.6%). Additionally, the event-free survival rate was higher with GPBA (77.1%, P =.033) and CBA (76.4%, P =.047) than POBA (58.8%).

CONCLUSIONS

In small coronary arteries, both GPBA and CBA resulted in favorable angiographic and clinical outcomes. With a lower restenosis rate and target lesion revascularization rate, GPBA may be a superior strategy for small vessels compared with POBA.

Bladed balloon angioplasty for peripheral pulmonary artery stenosis

Treatment for peripheral pulmonary artery stenosis is challenging, and conventional balloon angioplasty has not proved to be universally effective. Evaluated was the efficacy of bladed balloon (BB) dilation to address vessels resistant to conventional high-pressure (10-15 atm) balloon angioplasty (BA). Thirty-one procedures were performed on 14 children with age range 1 month to 15 years. The diameter of the BB ranged from 3 to 8 mm. After BB dilation, all children had subsequent conventional BA (balloon size range, 3-10 mm). The minimal lumen diameter (MLD) before and after the procedure, whether there was a waist at initial BA, and BB diameter-to-MLD ratio before the procedure were measured. A > 50% increase in MLD was considered successful. Four children had Williams syndrome, two children Alagille syndrome, five children Fallot's tetralogy, and three miscellaneous lesions. The resistant stenosis was located in the right central pulmonary artery in 6, right branch pulmonary artery in 7, left central pulmonary artery in 6, and left branch pulmonary artery in 12 lesions. Median BB diameter was 253% (117-440%) of the MLD and increased from 2.0 +/- 0.7 to 3.2 +/- 0.8 mm (P < 0.0001), with a mean increase of 73% +/- 62%. There was an inverse relationship between the MLD before and increase after the procedure (r = 0.75; P < 0.001). The BB diameter-to-MLD ratio before procedure was significantly associated with the increase in MLD (r = 0.70; P < 0.001). After the procedure, 18 of the 31 procedures were considered successful. In all successful procedures, the BB diameter was greater than twice the MLD before the procedure. Comparing children with Williams and Alagille syndrome with the remaining eight children, there were no significant differences in the increase in MLD. A small aneurysm and thrombus were noticed in two and three children, respectively, but no fatal complications were reported. BB angioplasty is effective for resistant peripheral pulmonary artery stenosis when conventional BA fails. The diameter of the BB should be larger than twice the minimal luminal diameter of the stenotic lesion.

Cutting balloon angioplasty vs. conventional balloon angioplasty in patients receiving intracoronary brachytherapy for the treatment of in-stent restenosis

The objective of this study was to evaluate the safety and efficacy of cutting balloon angioplasty (CBA) for the treatment of in-stent restenosis prior to intracoronary brachytherapy (ICB). Cutting balloon angioplasty may reduce the incidence of uncontrolled dissection requiring adjunctive stenting and may limit "melon seeding" and geographic miss in patients with in-stent restenosis who are subsequently treated with ICB. We performed a retrospective case-control analysis of 134 consecutive patients with in-stent restenosis who were treated with ICB preceded by either CBA or conventional balloon angioplasty. We identified 44 patients who underwent CBA and ICB, and 90 control patients who underwent conventional percutaneous transluminal coronary angioplasty (PTCA) and ICB for the treatment of in-stent restenosis. Adjunctive coronary stenting was performed in 13 patients (29.5%) in the CBA/ICB group and 41 patients (45.6%; P < 0.001) in the PTCA/ICB group. There was no difference in the injury length or active treatment (ICB) length. The procedural and angiographic success rates were similar in both groups. There were no statistically significant differences in the incidence of death, myocardial infarction, recurrent angina pectoris, subsequent target lumen revascularization, or the composite endpoint of all four clinical outcomes (P > 0.05). Despite sound theoretical reasons why CBA may be better than conventional balloon angioplasty for treatment of in-stent restenosis with ICB, and despite a reduction in the need for adjunctive coronary stenting, we were unable to identify differences in clinical outcome.

Increased Expression of Monocyte CD11a and Intracellular Adhesion Molecule-1 in Patients With Initial Atherosclerotic Coronary Stenosis

BACKGROUND

Cell adhesion molecules have been implicated in the adhesion of leukocytes to endothelial cells and therefore play a role in atherosclerosis, which is a frequent cause of morbidity and mortality in patients with coronary artery disease (CAD) or undergoing hemodialysis (HD). The levels of expression of leukocyte adhesion molecules were evaluated in patients with CAD or HD.

METHODS AND RESULTS

The expression of leukocyte (ie, neutrophil, monocyte and lymphocyte) surface CD11a, CD18, intracellular adhesion molecule-1 (ICAM-1), very late antigen-4 alpha (VLA-4 alpha) and L-selectin was investigated by flow cytometry in 20 patients who were initially diagnosed with CAD (CAD group), 15 patients with coronary re-stenosed vessels (RESTE group), 20 undergoing HD (HD group) and 20 without CAD (CONT group). Monocyte surface expression of both CD11a and ICAM-1 in the CAD group was significantly higher than in the CONT group. Interestingly, when 15 patients with RESTE were analyzed, they showed monocyte CD11a and ICAM-1 expression levels comparable to those in the CONT group. On the other hand, there were no significant differences in the expression of CD11a, CD18, L-selectin or VLA-4 alpha between the HD group and CONT group, but monocyte L-selectin was increased in the CAD group compared with the CONT group.

CONCLUSIONS

Because CD11a and CD18 are expressed on the cell surface as a heterodimer and ICAM-1 is a ligand for CD11a/CD18, this increased expression of CD11a and ICAM-1 may affect the development of initial atherosclerotic coronary stenosis, but not re-stenosis.

Impact of deep vessel wall injury on acute response and remodeling of coronary artery segments after cutting balloon angioplasty

Deep vessel wall injury is believed to affect vessel dimension following coronary intervention. The cutting balloon is designed to treat coronary artery stenoses with dilatation and surgical incisions, thereby reducing excess vessel injury. This study examines the effect of deep vessel wall injury on acute and late coronary arterial response after cutting balloon angioplasty. Serial volumetric intravascular ultrasound (IVUS) analyses were performed in 63 lesions treated with cutting balloon angioplasty alone. Before intervention, the longitudinal range of the lesion segment that included the smallest lumen area (LA) was determined as LA <4 mm(2) and/or LA stenosis >60%. The exact corresponding site at postintervention and follow-up was aligned using peri- and intravascular landmarks. Average vessel area (VA), plaque area (PA), and LA were measured. Lesion segments were categorized as with or without deep vessel wall injury, which was defined as the presence of plaque/vessel wall fracture extending to the sonolucent (medial) layer. Before intervention, the lesion vessel size of deep injury group was smaller than that of the nondeep injury group (p <0.05 for average VA and PA), whereas average lesion LA, lesion length, and reference vessel size did not differ. Immediately after cutting balloon angioplasty, the deep injury group showed a significant increase in VA (p <0.0001) and a lesser decrease in PA (p <0.01) compared with the nondeep injury group. During follow-up, the increase of VA tended to be greater in the deep injury group than in the nondeep injury group (p = 0.06), whereas the change of PA did not differ. Consequently, LA decrease was less in the deep injury group than in the nondeep injury group (p <0.05). From these results, it is suggested that deep vessel wall injury tends to occur in lesions with relatively small size and such lesions show favorable vessel response after cutting balloon angioplasty.

The safety and feasibility of transradial cutting balloon angioplasty: immediate results, benefits, and limitations

Cutting balloon angioplasty can reduce the restenosis rate more than conventional balloon angioplasty, but is traditionally performed through a femoral artery. However, it is not clear how useful a transradial approach would be for cutting balloon angioplasty. This study was conducted to examine the safety, feasibility, and limitations of transradial as opposed to transfemoral cutting balloon angioplasty. From November 1999 to August 2001, 177 patients underwent cutting balloon coronary angioplasty. We compared the success rate, angiographic results, and complication rates of two groups of patients, those undergoing transradial (168 lesions from 153 patients) and those undergoing transfemoral (24 lesions from 24 patients) cutting balloon angioplasty. In both groups of patients who had similar clinical and target lesion characteristics. the percentage of lesions that required balloon predilation (27.4% vs 29.2%). stenting (7.7% vs 4.2%), and adjunct balloon dilation (28.0% vs 33.3%) due to dissection (35.7% vs 33.3%) or suboptimal results were comparable. Both approaches achieved a 100% primary success rate with similar acute gain (2.02 +/- 0.68 mm vs 1.94 +/- 0.70 mm), residual (luminal) diameter stenosis (19.2 +/- 11.7% vs 17.0 +/- 12.7%). proportion of lesions that achieved TIMI 3 flow (98.8% vs 100%), and clinical success rate (98.8% vs 95.8%). However, patients undergoing transradial cutting balloon angioplasty had earlier ambulation and a significantly shorter hospital stay than those undergoing a transfemoral approach (2.80 +/- 2.67 days vs 4.75 +/- 5.44 days, P = 0.005). We conclude that the transradial approach is a feasible and safe alternative to the transfemoral approach for cutting balloon angioplasty. In addition, it offers patients early ambulation and a short hospital stay.

Comparison of cutting balloon vs stenting alone in small branch ostial lesions of native coronary arteries

Angioplasty of small vessels is associated with a higher rate of restenosis, even in the ostium. The present study compared the acute, late results of cutting balloon vs those of stenting alone in small branch ostial lesions of native coronary arteries and the effect on the parent vessel. The study group comprised 61 patients with successful angioplasty of smaller branch ostial lesions in native coronary arteries. The reference vessel diameter was between 2.5 and 3.0 mm. Patients were divided into 2 groups: group I (cutting balloon, n=30) and group II (stenting alone, n=31). After intervention, patients in group II achieved significant acute lumen gain, larger minimal lumen diameter (MLD) and less diameter stenosis. At 3-month follow-up, the MLD and diameter stenosis of the 2 groups were almost identical; however, late loss was lower in group I. At the 6-month follow up, the cumulative restenosis rate was 41% (11/27) in group I compared with 63% (19/31) in group II (p=0.05), and the target lesion revascularization was also lower in the cutting balloon group [29% (8/27) vs 53% (16/30) p=0.05]. In group 1, the MLD of the parent vessel did not change before, after cutting balloon or at follow-up. In contrast, there were significant reductions in parent vessel MLD following stenting alone and at follow-up. Plaque shift did not occur in the cutting balloon group. Cutting balloon angioplasty is a feasible approach for the treatment of small branch ostial lesions and does not cause significant narrowing of the parent vessel.

Mechanisms of acute lumen gain following cutting balloon angioplasty in calcified and noncalcified lesions: an intravascular ultrasound study

Several studies have shown that mechanisms for lumen enlargement following conventional balloon angioplasty (BA) consist of plaque reduction and vessel expansion. To assess the mechanisms of lumen enlargement after Cutting Balloon (CB) angioplasty, intravascular ultrasound images were analyzed in 180 lesions (89 CB and 91 BA). External elastic membrane (EEM) cross-sectional area (CSA), lumen CSA, and plaque plus media (P+M) CSA were measured before and after angioplasty. In the CB group, lower balloon pressure was utilized (P < 0.0001). DeltaP+M CSA was significantly larger (P = 0.02) and deltalumen CSA showed a trend toward being larger (P = 0.07) compared to BA group. For noncalcified lesions, CB resulted in a larger deltaP+M CSA (P < 0.05) and a smaller deltaEEM CSA (P = 0.10) than BA. For calcified lesions, deltalumen CSA was significantly larger in the CB group (P < 0.05) without significant differences in deltaEEM CSA and deltaP+M CSA. Dissections complicated with calcified lesions were associated with larger deltalumen CSA for the CB group. In conclusion, for noncalcified lesions, CB achieves similar luminal dimensions with larger plaque reduction and less vessel expansion compared to BA. On the other hand, for calcified lesions, the CB achieves larger lumen gain, especially in lesions with evidence of dissections.

Randomized comparison of cilostazol versus ticlopidine hydrochloride for antiplatelet therapy after coronary stent implantation for prevention of late restenosis

BACKGROUND

Cilostazol is a newly developed antiplatelet drug that has been widely applied for clinical use. Its antiplatelet action appears to be mainly related to inhibition of intracellular phosphodiesterase activity. Recently, cilostazol has been used for antiplatelet therapy after coronary stent implantation. However, its evaluation has not been established yet.

METHODS

This prospective randomized trial was designed to investigate the efficacy of cilostazol for the prevention of late restenosis and acute or subacute stent thrombosis in comparison with ticlopidine hydrochloride. One hundred thirty consecutive patients, scheduled for elective coronary stenting, were randomly assigned to receive oral aspirin (81 mg/day) plus ticlopidine hydrochloride therapy (200 mg/day; group I) or aspirin plus cilostazol therapy (200 mg/day; group II). These medications were started at least 2 days before coronary intervention and continued until follow-up coronary angiography was performed 6 months later.

RESULTS

Subacute stent thrombosis was observed in 2 patients of group I but in no patients of group II. Major cardiac events were similarly present in both groups. Elevated transaminase levels were observed more frequently in group I than in group II (P <.05). Each of the quantitative coronary angiography variables before and immediately after coronary stenting were similar in both groups. At follow-up angiography, however, late lumen loss (0.69 +/- 0.79 mm vs 0.28 +/- 0.40 mm; P <.01) and loss index (0.42 +/- 0.56 vs 0.16 +/- 0.27; P <.01) were smaller in group II than in group I. Restenosis rate (13% vs 31%; P <.05) and target lesion revascularization rate (7% vs 21%; P <.05) were both lower in group II than in group I.

CONCLUSION

Aspirin plus cilostazol therapy may be an effective regimen for prevention of not only stent thrombosis but also restenosis.

Association of a CD18 gene polymorphism with a reduced risk of restenosis after coronary stenting

Inflammatory mechanisms play an important role in the process of restenosis after percutaneous coronary interventions, with cell adhesion molecules, including Mac-1 (CD11b/CD18), as key mediators. A single nucleotide polymorphism, 1323C/T, located in exon 11 of the CD18 gene has been previously described, but its functional and clinical significances have not yet been studied. We assessed whether an association exists between this polymorphism and restenosis after coronary stenting. Clinical and angiographic measures of restenosis were evaluated over 1 year after coronary stent placement in 1,207 consecutive patients. Angiographic restenosis was defined as a > or =50% diameter stenosis at follow-up angiography. Determination of the CD18 1323C/T genotype was based on the polymerase chain reaction technique. The frequency of the T allele was 0.34 and its presence reduced the 1-year risk of a major adverse cardiac event (death, myocardial infarction, target vessel revascularization) by 29% (p = 0.011). Carriers of the T allele had a significantly lower risk of angiographic restenosis compared with noncarriers (odds ratio 0.71, 95% confidence interval 0.55 to 0.92). The incidence of restenosis decreased as a function of the number of T alleles: 38.1% in patients with genotype CC, 31.7% in patients with genotype CT, and 26.0% in patients with genotype TT (p = 0.004). Thus, the 1323T allele of the CD18 gene is associated, in a gene dose-dependent manner, with a lower incidence of angiographic restenosis after coronary stenting. This finding suggests that Mac-1 is involved in the development of restenosis after coronary stent placement.

Standalone cutting balloon angioplasty for the treatment of stent-related restenosis: acute results and 3- to 6-month angiographic recurrent restenosis rates

Despite excellent acute reperfusion results, 20%-30% of patients who undergo coronary stent implantation will develop angiographic restenosis and may require same additional treatments. Cutting Balloon angioplasty (CBA) causes less histological damage outside of the incised area than a regular balloon. However, regular plain old balloon angioplasty is sometimes required before CBA, as is adjunctive stenting and adjunctive angioplasty. These adjunctive strategies may negate the advantages of CBA. There is little data available on CBA as a standalone therapy for stent-related restenosis (SRS). The aim of this study was to evaluate the acute and 3- to 6-month angiographic recurrent restenosis rates following standalone CBA in a patient population treated for SRS and in whom optimal acute results were obtained. In this study, 40 patients with SRS (54 lesions) underwent standalone CBA with optimal acute results. For all lesions, coronary angiography was conducted before and after a standalone CBA procedure for SRS and systematically during 3-6 months to assess recurrent angiographic restenosis rates in the study population. In the study lesions, SRS was either diffuse disease (> 15 mm; 52%) or focal type (48%). Cutting Balloon diameter was 3.20 +/- 0.44 mm and maximal inflation pressure 8.7 +/- 1.2 atm. Ratio of Cutting Balloon diameter to restenotic stent diameter was 0.996 +/- 0.487. Multiple inflations (6 +/- 3 times) were performed. Number of used Cutting Balloon was 1.02 +/- 0.14. Complications were as follows; one non-Q-wave MI (1.9%); 0 death (0%), and 17 repeat target lesion revascularizations (TLRs; 32%). Follow-up coronary angiography (CAG) was not attained for one patient. The angiographic recurrent restenosis rate was 34%, with a higher rate observed when the SRS was diffuse type, 50% vs. 16% for focal-type SRS (P < 0.01). The recurrent restenosis rate for smaller vessels (vessel diameter < or = 3.0 mm) was the same as for larger ones. At follow-up CAG, diffuse-type recurrent restenosis (56%) presented nearly as frequently as that presenting in the original SRS lesions (52%). But four diffuse-type SRS (29%) changed into focal-type recurrent stenosis. In this study, standalone CBA for SRS with optimal acute results was associated with an angiographic restenosis rate of 34%. Diffuse-type disease had a higher recurrent restenosis rate. When CBA achieves acute optimal results, adjunctive stenting or adjunctive PTCA are not always necessary, particularly when the SRS is focal. As a result of CBA, some diffuse-type SRS may change into focal-type recurrent stenosis by the time of the next intervention.

Final results of the CAPAS trial

BACKGROUND

The Cutting Balloon (Interventional Technologies Inc) is a new-concept balloon that incorporates 3 to 4 blades to create sharp incisions on the luminal surface of the lesion during dilation without causing severe tearing injury to the vessel wall. It may reduce restenosis and improve clinical outcome.

METHODS

Two hundred forty-eight lesions were randomly assigned to Cutting Balloon angioplasty (CBA, 120 lesions) or conventional balloon angioplasty (PTCA, 128 lesions). Inclusion criteria were type B/C lesions (American College of Cardiology/American Heart Association classification) and reference diameter <3.0 mm by visual image on angiogram. Quantitative coronary angiography was performed before and after percutaneous coronary angioplasty and at 3-month follow-up. The primary end point was restenosis, defined as >/=50% diameter stenosis at follow-up. Clinical event rates at 1 year were assessed.

RESULTS

Baseline characteristics were similar. Reference diameter was small in both groups (2.16 vs 2.18 mm, CBA vs PTCA). Preprocedural percent diameter stenosis (%DS) was similar (69.8% vs 69.6%). However, postprocedural and follow-up %DS were lower (26.2% vs 28.9%, P =.072; 40.8% vs 47.5%, P =.011) in the CBA group. Restenosis was significantly lower (25.2% vs 41.5%, P =.009) in the CBA group. At 1 year, event-free survival was achieved in 72.8% of the CBA group and in 61.0% of the PTCA group (P =.047).

CONCLUSION

These findings suggest that CBA provides superior angiographic and clinical outcomes in comparison with PTCA in small coronary arteries.

Inflammation as a key event in the development of neointima following vascular balloon injury

1. The present review discusses the current evidence to implicate leucocytes as key players in the development of neointima in arteries that have been subjected to balloon angioplasty injury. 2. There is substantial clinical evidence that leucocytes are activated after angioplasty, as determined by increased plasma levels of both leucocyte granulation products and soluble leucocyte and endothelial cell adhesion molecules. 3. Experimental evidence to implicate leucocytes in neointimal formation comes from studies that demonstrate leucocyte accumulation occurs within the vascular wall soon after injury and that induction of leukopenia prevents neointimal formation. 4. The evidence implicating specific adhesion molecules and cytokines in the key events leading to neointimal formation is discussed.

Activation of the immune system and coronary artery disease: the role of anti-endothelial cell antibodies

On the basis of the role of immuno-mediated inflammation in atherosclerosis we investigated, (1) the prevalence of anti-endothelial cell antibodies (AECA) in ischaemic heart disease (IHD); (2) if beta2-glycoprotein I (beta2-GPI) was the target antigen of AECA; (3) the relationship between AECA, tissue factor (TF) and tissue factor pathway inhibitor (TFPI). In 93 consecutive IHD patients undergoing percutaneous transluminal coronary angioplasty (PTCA) and 105 controls AECA were detected by ELISA on human umbilical vein endothelial cells (HUVEC). AECA positive sera were evaluated for anti-beta2-GPI antibodies by ELISA. TF and TFPI plasma levels were assessed by ELISA. Twelve of 93 (12.9%) IHD patients and only one of 105 controls (0.95%) were AECA positive. The prevalence of AECA was higher in unstable angina (UA) than in effort angina (EA) (P=0.01). Three of 12 AECA positive sera resulted positive for anti-beta2-GPI and showed a marked decrease in EC-binding when tested on HUVEC cultured in serum-free medium. The binding was restored by the addition of beta2-GPI. TF and TFPI levels were similar in AECA positive and AECA negative patients. The rate of angiographically documented clinical recurrences was 66.7% in the AECA positive and 14.8% in the AECA negative group (P=0.0004) with a significant relationship between restenosis and AECA (P<0.0001), unchanged by the inclusion of cardiovascular risk factors in the regression model. Our results suggest a 'role' for AECA in the immune-mediated inflammation in UA beta2-GPI is not the only AECA target antigen. AECA are not responsible for high TF and TFPI levels. The high rate of clinical recurrences after PTCA, confirmed by angiography, in AECA positive patients is in line with such a role and suggests further large-scale 'ad hoc' studies.

Response of inflammatory markers to balloon angioplasty in peripheral arterial occlusive disease

OBJECTIVES

To study the inflammatory response to balloon angioplasty (PTA).

DESIGN

Prospective study.

MATERIALS

Blood samples were drawn for cytokine analysis from 10 patients undergoing PTA before, after 60 min and 6 h after the balloon inflation. Adhesion molecules were analysed in 14 patients undergoing PTA and in seven patients undergoing angiography only. Arterial samples were taken in eight patients, before PTA, immediately after and 15 min later. Venous samples were taken in six patients and in the group undergoing angiography only. The sampling was before, 60, 90 and 120 min after the procedure. As controls served 15 patients with no signs of peripheral arterial disease.

METHODS

Cytokines (IL-6, TNF-alpha) were analysed using ELISA. Adhesion molecule expression on WBC was measured by flow cytometry.

RESULTS

A significant increase of IL-6 in the sample taken 6 h after the last balloon inflation was seen in five patients. TNF-alpha was raised only in one patient. The group of patients with peripheral arterial occlusive disease (PAOD) expressed pre-interventionally a higher level of adhesion molecules on WBC compared to the controls. The expression of adhesion molecules (CD11b/CD18) was significantly decreased after PTA.

CONCLUSION

Only a very limited cytokine response is caused by PTA reflecting the small surgical trauma. PTA results in a downregulation of detectable CD11b/CD18 expression on WBC in the circulation, which may reflect removal of activated cells through adhesion and extravasation.

Comparison of activation process of platelets and neutrophils after coronary stent implantation versus balloon angioplasty for stable angina pectoris

The pathophysiologic features of stent-induced cellular responses of platelets and leukocytes have not been established. This study was designed to clinically investigate the activation of platelets and neutrophils after coronary stenting and to identify its effects on the long-term results of coronary stents. Forty-eight consecutive patients with left anterior descending coronary artery disease indicating coronary intervention were randomly assigned to either a balloon angioplasty group or a coronary stent group. Flow cytometric analysis demonstrated that the transcardiac gradient (the value of coronary sinus blood minus the value of peripheral blood) of platelet surface expression of CD62P (p < 0.001) and CD63 (p < 0.01) increased immediately after coronary stenting, but increased less significantly immediately after balloon angioplasty (CD62P, p < 0.01; CD63, p < 0.05). These increases were persistently observed after coronary stenting but transiently after balloon angioplasty alone during a 48-hour observation period after the procedures. The gradient for neutrophil surface expression of CD11b increased, and that of CD62 L decreased 48 hours after coronary stenting (CD11b, p < 0.001; CD62 L, p < 0.05), but these changes showed less significance 48 hours after balloon angioplasty alone (CD11b, p < 0.05; CD62 L, p = NS). The gradients 48 hours after the procedures for both CD62P (r = 0.39, p < 0.05) and CD11b (r = 0.44, p < 0.01) were independently correlated with the late loss in the stent group, whereas the correlation was seen only for CD11b (r = 0.38, p < 0.05) in the balloon angioplasty group. Both platelet and neutrophil activation was greater after coronary stenting than after balloon angioplasty. Cellular interactions between platelets and neutrophils may be related to the progression of neointimal proliferation leading to restenosis after coronary stent implantation.

VLA-4 (α4β1) engagement defines a novel activation pathway for β2 integrin–dependent leukocyte adhesion involving the urokinase receptor

During acute inflammatory processes, β2 and β1 integrins sequentially mediate leukocyte recruitment into extravascular tissues. We studied the influence of VLA-4 (very late antigen-4) (4β1) engagement on β2 integrin activation-dependent cell-to-cell adhesion. Ligation of VLA-4 by the soluble chimera fusion product vascular cell adhesion molecule-1 (VCAM-1)–Fc or by 2 anti-CD29 (β1 chain) monoclonal antibodies (mAb) rapidly induced adhesion of myelomonocytic cells (HL60, U937) to human umbilical vein endothelial cells (HUVECs). Cell adhesion was mediated via β2 integrin (LFA-1 and Mac-1) activation: induced adhesion to HUVECs was inhibited by blocking mAbs anti-CD18 (70%-90%), anti-CD11a (50%-60%), or anti-CD11b (60%-70%). Adhesion to immobilized ligands of β2 integrins (intercellular adhesion molecule-1 [ICAM-1], fibrinogen, keyhole limpet hemocyanin) as well as to ICAM-1–transfected Chinese hamster ovary cells, but not to ligands of β1 integrins (VCAM-1, fibronectin, laminin, and collagen), was augmented. VCAM-1–Fc binding provoked the expression of the activation-dependent epitope CBRM1/5 of Mac-1 on leukocytes. Clustering of VLA-4 through dimeric VCAM-1–Fc was required for β2 integrin activation and induction of cell adhesion, whereas monovalent VCAM-1 or Fab fragments of anti-β1 integrin mAb were ineffective. Activation of β2 integrins by 4β1 integrin ligation (VCAM-1–Fc or anti-β1 mAb) required the presence of urokinase receptor (uPAR) on leukocytic cells, because the removal of uPAR from the cell surface by phosphatidylinositol-specific phospholipase C reduced cell adhesion to less than 40%. Adhesion was reconstituted when soluble recombinant uPAR was allowed to reassociate with the cells. Finally, VLA-4 engagement by VCAM-1–Fc or anti-β1 integrin mAb induced uPAR-dependent adhesion to immobilized vitronectin as well. These results elucidate a novel activation pathway of β2 integrin–dependent cell-to-cell adhesion that requires 4β1 integrin ligation for initiation and uPAR as activation transducer.

VLA-4 (α4β1) engagement defines a novel activation pathway for β2 integrin–dependent leukocyte adhesion involving the urokinase receptor

During acute inflammatory processes, β2 and β1 integrins sequentially mediate leukocyte recruitment into extravascular tissues. We studied the influence of VLA-4 (very late antigen-4) (4β1) engagement on β2 integrin activation-dependent cell-to-cell adhesion. Ligation of VLA-4 by the soluble chimera fusion product vascular cell adhesion molecule-1 (VCAM-1)–Fc or by 2 anti-CD29 (β1 chain) monoclonal antibodies (mAb) rapidly induced adhesion of myelomonocytic cells (HL60, U937) to human umbilical vein endothelial cells (HUVECs). Cell adhesion was mediated via β2 integrin (LFA-1 and Mac-1) activation: induced adhesion to HUVECs was inhibited by blocking mAbs anti-CD18 (70%-90%), anti-CD11a (50%-60%), or anti-CD11b (60%-70%). Adhesion to immobilized ligands of β2 integrins (intercellular adhesion molecule-1 [ICAM-1], fibrinogen, keyhole limpet hemocyanin) as well as to ICAM-1–transfected Chinese hamster ovary cells, but not to ligands of β1 integrins (VCAM-1, fibronectin, laminin, and collagen), was augmented. VCAM-1–Fc binding provoked the expression of the activation-dependent epitope CBRM1/5 of Mac-1 on leukocytes. Clustering of VLA-4 through dimeric VCAM-1–Fc was required for β2 integrin activation and induction of cell adhesion, whereas monovalent VCAM-1 or Fab fragments of anti-β1 integrin mAb were ineffective. Activation of β2 integrins by 4β1 integrin ligation (VCAM-1–Fc or anti-β1 mAb) required the presence of urokinase receptor (uPAR) on leukocytic cells, because the removal of uPAR from the cell surface by phosphatidylinositol-specific phospholipase C reduced cell adhesion to less than 40%. Adhesion was reconstituted when soluble recombinant uPAR was allowed to reassociate with the cells. Finally, VLA-4 engagement by VCAM-1–Fc or anti-β1 integrin mAb induced uPAR-dependent adhesion to immobilized vitronectin as well. These results elucidate a novel activation pathway of β2 integrin–dependent cell-to-cell adhesion that requires 4β1 integrin ligation for initiation and uPAR as activation transducer.

Interleukin 6 expression in coronary circulation after coronary angioplasty as a risk factor for restenosis

OBJECTIVE

To investigate changes in cytokine expression in the coronary circulation induced by percutaneous transluminal coronary angioplasty (PTCA).

METHODS

The study involved 32 patients with ischaemic heart disease who underwent elective PTCA for isolated stenotic lesions of the left coronary artery. Ten patients had plain old balloon angioplasty, 10 had percutaneous transluminal rotational atherectomy, and 12 had stent implantation. Blood samples were drawn from the coronary sinus before and immediately after PTCA. Plasma concentrations of interleukin 6 (IL-6), platelet derived growth factor (PDGF), monocyte chemoattractant protein 1 (MCP-1), and macrophage coronary stimulating factor (M-CSF) were measured. The patients were scheduled for follow up angiography six months after PTCA. Late loss index was calculated using quantitative coronary angiography.

RESULTS

IL-6 concentrations in coronary sinus blood increased immediately after PTCA (p < 0.001), but there was no change in PDGF, MCP-1, or M-CSF. There was a positive correlation between changes in IL-6 concentrations immediately after PTCA and late loss index six months after PTCA (r = 0.73, p < 0.001). IL-6 concentrations in coronary sinus blood were higher in patients with late restenosis than in those without restenosis (p < 0.001).

CONCLUSIONS

PTCA induces IL-6 production in the coronary circulation. This may induce subsequent inflammatory responses in injured vessels and play an important role in late restenosis after PTCA.

Influence of residual stenosis in determining restenosis after cutting balloon angioplasty

The cutting balloon is a new device for coronary angioplasty, which, by the combination of incision and dilatation of the plaque, is believed to minimize arterial wall trauma, the neoproliferative response, and subsequent restenosis. In this study, we sought to determine predictors of the restenosis using this technique. Seventy-seven patients underwent successful coronary angioplasty with cutting balloon alone. In 67 of these patients (87%), we performed a control angiogram at 6-month follow-up. Pre-, post-, and late angiographic results were evaluated by quantitative coronary analysis. Clinical and angiographic variables were correlated with restenosis as a binary variable and a continuous variable (late loss and late minimum luminal diameter). Univariate analysis showed that the immediate postprocedure minimum luminal diameter (MLD) was smaller in the restenotic group (defined as MLD > 50% by quantitative coronary angiography) than in the nonrestenotic group (1.90 +/- 0.47 mm vs. 2.19 +/- 0.56 mm, P < 0.05). In addition, the immediate percentage of stenosis was higher in the restenotic group than in the nonrestenotic group (37% +/- 10% vs. 27% +/- 11%, P < 0. 003). Multivariate analysis identified the immediate postcutting balloon percentage of stenosis as an independent determinant of binary restenosis (P < 0.008). When restenosis was defined as a continuous variable, the immediate postprocedure MLD was an independent predictor of late loss (P < 0.02) and of late MLD (P < 0. 0002). No clinical, preprocedure angiographic, or technical variables tested were associated with restenosis. The degree of postprocedural residual stenosis after cutting balloon angioplasty is predictive of late restenosis.