Plaque characterisation by Virtual Histology intravascular ultrasound analysis in patients with type 2 diabetes.

OBJECTIVES: To evaluate the in-vivo plaque composition and characteristics in patients with type 2 diabetes mellitus (DM) using Virtual Histology intravascular ultrasound (VH IVUS). METHODS: In 90 patients with stable angina pectoris, de novo target vessels were studied and plaque components were analysed. Patients were divided into two groups: a diabetic group (36 vessels) and a non-diabetic group (54 vessels). RESULTS: The percentage area of necrotic core and dense calcium were significantly larger in the DM group than the non-DM group (necrotic core: 11.0% (interquartile range (IQR): 7.2-15.2%) vs 7.6% (IQR 5.6-13.2%), p = 0.03; dense calcium: 5.6% (IQR: 2.3-7.3%) vs 2.9% (IQR: 1.7-4.9%), p = 0.01). The DM group presented with a significantly higher presence of at least one VH IVUS-derived thin-cap fibroatheroma (VHD-TCFA) (75% vs 41%, p = 0.001) and VH IVUS-derived fibrocalcific atheroma (VHD-FCA) (75% vs 40%, p = 0.001). In the DM group, 53% of the vessels had both VHD-TCFA and VHD-FCA, which was significantly higher than non-DM group (17%, p = 0.0004). CONCLUSIONS: Coronary plaque characteristics in DM patients showed an increased amount of dense calcium and necrotic core, as well as a higher frequency of VHD-TCFA and VHD-FCA. Atherosclerosis of the target vessel was more advanced in diabetic patients.

Serial six year quantitative angiographic follow up in asymptomatic patients following successful coronary angioplasty.

OBJECTIVE: To evaluate long term (six years) lumen changes after balloon angioplasty by using quantitative coronary angiography. METHODS: Complete serial quantitative coronary angiography (before and after angioplasty and at six months, three years, and six years) was performed in 100 patients with successful angioplasty and without subsequent repeated revascularisation. In all, 198 dilated segments were compared with 395 non-dilated segments that were obtained from non-target arteries of study patients. RESULTS: From six months to three years after angioplasty, minimum lumen diameter (MLD) increased significantly by 0.13 (0.28) (mean (SD)) mm in dilated segments and decreased significantly by 0.04 (0.27) mm in non-dilated segments. From three years to six years, MLD remained stable in dilated segments but decreased further (by 0.04 (0.28) mm) in non-dilated segments. Consequently, the DeltaMLD between six months and six years was larger in dilated segments than in non-dilated segments (0.12 (0.32) v -0.08 (0.34); p < 0.001). Further, DeltaMLD from six months to six years correlated positively with the percentage diameter stenosis (DS) at six months in each group (dilated segments r = 0.47, p < 0.0001; non-dilated segments r = 0.49, p < 0.0001). Multivariate analysis showed that the only independent predictor of DeltaMLD over six years for each group was the DS at six months. CONCLUSIONS: Lesion regression occurs within the first three years after angioplasty and reaches a plateau thereafter. Moreover, the stenosis severity at six months predicts the magnitude of late regression after angioplasty.

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.

Impact of pre-stent plaque debulking for chronic coronary total occlusions on restenosis reduction.

BACKGROUND: While stenting improves the long-term angiographic outcomes of successfully recanalized chronic coronary total occlusions (CTO), the restenosis rate still remains high. The massive plaque burden in CTO is considered to be one of the causes of in-stent restenosis. METHODS: We examined the pre-stent plaque debulking strategy with high-speed rotational atherectomy (RA) for 50 CTO (Thrombolysis in Myocardial Infarction flow grade 0; estimated occlusive duration, 3 months). Angiographic follow-up results were compared to those of 120 consecutive CTO recanalized with primary stenting in which RA could be indicated retrospectively. Angiographic restenosis was defined as diameter stenosis > 50% at 6-month follow-up. RESULTS: RA could be performed safely in all lesions without any major complications. Adjunctive ballooning and stenting could be performed without high-pressure dilatation (8.4 +/- 1.7 atmospheres). Follow-up angiography was performed in 48 lesions 184 +/- 61 days after the procedure. There were no significant differences in baseline characteristics between the two groups; however, the implanted stent type was different. Quantitative coronary angiography revealed that diameter stenosis was smaller at follow-up (36.2 +/- 20.0% versus 52.2 +/- 26.7%; p = 0.0003) as well as post-procedure (7.8 +/- 11.5% versus 17.8 +/- 13.6%; p < 0.0001) compared with the control group. Angiographic restenosis was also significantly reduced (29.2% versus 52.5%; p = 0.0061). CONCLUSIONS: RA is a safe procedure for plaque debulking of CTO in selected cases. Plaque debulking of CTO facilitates subsequent stent expansion and may reduce the restenosis rate.

The Potential of Cilostazol in Interventional Cardiology.

Cilostazol, an antiplatelet agent developed in Japan, has been demonstrated to have the potential to reduce restenosis after percutaneous transluminal coronary angioplasty (PTCA). Unlike conventional antiplatelet agents, cilostazol has several favorable properties in reducing restenosis. Besides the vasodilatory effect, cilostazol directly inhibits smooth muscle proliferation and may enhance reendothelialization after PTCA. Although the magnitude of prevention of restenosis may differ with the PTCA device used, cilostazol appears quite promising as a pharmacologic treatment adjunct to PTCA.

Percutaneous myocardial ablation in double-chamber right ventricle.

Double-chamber right ventricle (DCRV) exhibits intracavitary outflow obstruction. We report the first case of percutaneous myocardial ablation of DCRV in a 73-year-old patient. An alcohol-induced conus branch occlusion provided the reduction of pressure gradient from 81 to 48 mm Hg and clinical improvement. This strategy may be an alternative therapy to surgery in the adult patients with DCRV. Cathet. Cardiovasc. Intervent. 49:97-101, 2000.

Effects of adjunctive balloon angioplasty after intravascular ultrasound-guided optimal directional coronary atherectomy: the result of Adjunctive Balloon Angioplasty After Coronary Atherectomy Study (ABACAS).

OBJECTIVES: This study was conducted to evaluate: 1) the effect of adjunctive percutaneous transluminal coronary angioplasty (PTCA) after directional coronary atherectomy (DCA) compared with stand-alone DCA, and 2) the outcome of intravascular ultrasound (IVUS)-guided aggressive DCA. BACKGROUND: It has been shown that optimal angiographic results after coronary interventions are associated with a lower incidence ofrestenosis. Adjunctive PTCA after DCA improves the acute angiographic outcome; however, long-term benefits of adjunctive PTCA have not been established. METHODS: Out of 225 patients who underwent IVUS-guided DCA, angiographically optimal debulking was achieved in 214 patients, then theywere randomized to either no further treatment or to added PTCA. RESULTS: Postprocedural quantitative angiographic analysis demonstrated an improved minimum luminal diameter (2.88 +/- 0.48 vs. 2.6 +/- 0.51 mm; p = 0.006) and a less residual stenosis (10.8% vs.15%; p = 0.009) in the adjunctive PTCA group. Quantitative ultrasound analysis showed a larger minimum luminal diameter (3.26 +/- 0.48 vs. 3.04 +/- 0.5 mm; p < 0.001) and lower residual plaque mass in the adjunctive PTCA group (42.6% vs. 45.6%; p < 0.001). Despite the improved acute findings in the adjunctive PTCA group, six-month angiographic and clinical results were not different. The restenosis rate (adjunctive PTCA 23.6%, DCA alone 19.6%; p = ns) and target lesion revascularization rate (20.6% vs. 15.2%; p = ns) did not differ between the groups. CONCLUSIONS: With IVUS guidance, aggressive DCA can safely achieve optimal angiographic results with low residual plaque mass, and this was associated with a low restenosis rate. Although adjunctive PTCA after optimal DCA improved the acute quantitative coronary angiography and quantitative coronary ultrasonography outcomes, its benefit was not maintained at six months.

Final results of the STent versus directional coronary Atherectomy Randomized Trial (START)

OBJECTIVES: This study was designed to compare primary stenting with optimal directional coronary atherectomy (DCA). BACKGROUND: No previous prospective randomized trial comparing stenting and DCA has been performed. METHODS: One hundred and twenty-two lesions suitable for both Palmaz-Schatz stenting and DCA were randomly assigned to stent (62 lesions) or DCA (60 lesions) arm. Single or multiple stents were implanted with high-pressure dilation in the stent arm. Aggressive debulking using intravascular ultrasound (IVUS) was performed in the DCA arm. Serial quantitative angiography and IVUS were performed preprocedure, postprocedure and at six months. The primary end point was restenosis, defined as > or =50% diameter stenosis at six months. Clinical event rates at one year were also assessed. RESULTS: Baseline characteristics were similar. Procedural success was achieved in all lesions. Although the postprocedural lumen diameter was similar (2.79 vs. 2.90 mm, stent vs. DCA), the follow-up lumen diameter was significantly smaller (1.89 vs. 2.18 mm; p = 0.023) in the stent arm. The IVUS revealed that intimal proliferation was significantly larger in the stent arm than in the DCA arm (3.1 vs. 1.1 mm ; p < 0.0001), which accounted for the significantly smaller follow-up lumen area of the stent arm (5.3 vs. 7.0 mm2; p = 0.030). Restenosis was significantly lower (32.8% vs. 15.8%; p = 0.032), and target vessel failure at one year tended to be lower in the DCA arm (33.9% vs. 18.3%; p = 0.056). CONCLUSIONS: These results suggest that aggressive DCA may provide superior angiographic and clinical outcomes to primary stenting.

Impact of cilostazol on restenosis after percutaneous coronary balloon angioplasty.

BACKGROUND: Restenosis after percutaneous transluminal coronary (balloon) angioplasty (PTCA) remains a major drawback of the procedure. We previously reported that cilostazol, a platelet aggregation inhibitor, inhibited intimal proliferation after directional coronary atherectomy and reduced the restenosis rate in humans. The present study aimed to determine the effect of cilostazol on restenosis after PTCA. METHODS AND RESULTS: Two hundred eleven patients with 273 lesions who underwent successful PTCA were randomly assigned to the cilostazol (200 mg/d) group or the aspirin (250 mg/d) control group. Administration of cilostazol was initiated immediately after PTCA and continued for 3 months of follow-up. Quantitative coronary angiography was performed before PTCA and after PTCA and at follow-up. Reference diameter, minimal lumen diameter, and percent diameter stenosis (DS) were measured by quantitative coronary angiography. Angiographic restenosis was defined as DS at follow-up >50%. Eligible follow-up angiography was performed in 94 patients with 123 lesions in the cilostazol group and in 99 patients with 129 lesions in the control group. The baseline characteristics and results of PTCA showed no significant difference between the 2 groups. However, minimal lumen diameter at follow-up was significantly larger (1.65+/-0.55 vs 1.37+/-0.58 mm; P<0.0001) and DS was significantly lower (34.1+/-17.8% vs 45.6+/-19. 3%; P<0.0001) in the cilostazol group. Restenosis and target lesion revascularization rates were also significantly lower in the cilostazol group (17.9% vs 39.5%; P<0.001 and 11.4% vs 28.7%; P<0. 001). CONCLUSIONS: Cilostazol significantly reduces restenosis and target lesion revascularization rates after successful PTCA.

Percutaneous revascularization of lesions with saphenous vein graft failure: influence of chronic total occlusion on early outcome.

The purpose of this study was to evaluate a therapeutic strategy of percutaneous transluminal coronary angioplasty (PTCA) in patients with recurrent angina following coronary artery bypass grafting. The study looked at 112 branches associated with graft failure, excluding new lesions in the native coronary artery (NCA). Chronic total occlusion (CTO) was observed in 50% of NCA (56/112) and in 68% of the grafts (76/112). Thirty-three branches (29%) showed CTO in both NCA and the graft. The overall success rate was 86% (96/112). The success rate on NCA was 98% (44/45) in non-CTO, while in CTO it was significantly lower at 62% (18/29). As to grafts, the success rate was 94% (32/34) in non-CTO, while it was 50% (2/4) in CTO. These characteristics, with respect to lesion morphology and the prevalence of CTO, exerted an influence on the selection of the access vessels for revascularization. Early outcome depended on the result of treatment of CTO.

Transluminal percutaneous septal myocardial ablation in a patient with hypertrophic obstructive cardiomyopathy.

Reduction of septal mass by inducing septal infarction using catheter techniques is a new therapy for hypertrophic obstructive cardiomyopathy (HOCM). We report a case of severe HOCM that was dramatically improved by this non-surgical treatment. A 60-year-old woman with HOCM had suffered dyspnea (NYHA class III) with syncopal attack despite medical treatment. Left heart catheterization showed a resting pressure gradient across the left ventricular outflow tract of 156 mmHg. Two proximal septal branches of the anterior descending coronary artery were catheterized with a balloon catheter by the usual percutaneous coronary angioplasty techniques and were completely blocked by injection of absolute alcohol. The pressure gradient decreased to 26 mmHg after the procedure. Symptoms were markedly improved (NYHA class I) without any medical treatment. The reduced pressure gradient was maintained at the 3-month follow-up catheterization (36 mmHg). Further long-term follow-up is needed, but this treatment would seem to to be a promising technique for reducing pressure gradient in symptomatic patients with HOCM.

Comparison of quantitative coronary angiographic results after directional coronary atherectomy and balloon angioplasty of protected left main coronary stenosis.

We compared the angiographic and clinical outcomes after directional coronary atherectomy (DCA, 13 patients) with those after conventional balloon angioplasty (BA, 21 patients) in patients with protected left main coronary artery stenosis. The initial success rate was 100% in the DCA group and 81% (17 of 21) in the BA group. Restenosis was present in 2 of 11 patients in the DCA group and 9 of 16 patients in the BA group (18% vs. 56%, P < 0.05). DCA and BA improved a minimal lumen diameter. The initial gain after DCA was greater than that after BA. At follow-up, the minimal lumen diameter was larger and the percentage diameter stenosis was smaller in the DCA group than in the BA group. The late loss and loss index were equivalent in both groups. Compared with conventional BA, DCA in protected left main coronary artery stenosis is associated with a higher angiographic success rate and provides a wider luminal diameter with reduced incidence of restenosis.

Impact of cilostazol on intimal proliferation after directional coronary atherectomy.

Cilostazol, a novel platelet aggregation inhibitor, inhibits intimal proliferation in animal models. We randomly assigned 41 patients with lesions suitable for directional coronary atherectomy to the cilostazol group (200 mg/day) or the aspirin (250 mg/day) group. Medication was started before directional coronary atherectomy and was continued to a 6-month follow-up. Serial quantitative coronary angiography and intravascular ultrasound study were performed. Baseline characteristics were not different between the two groups. However, the minimal lumen diameter at follow-up was larger (2.33 +/- 0.60 mm vs 1.81 +/- 0.68 mm, p = 0.016) and the percent diameter stenosis (24.5% +/- 16.6% vs 40.9% +/- 21.0%, p = 0.010) was smaller in the cilostazol group. The change in vessel area was not different, but the percent plaque area at follow-up was smaller in the cilostazol group (55.7% +/- 11.2% vs 64.5% +/- 14.5%, p = 0.044). The restenosis rate was significantly lower in the cilostazol group (0% vs 26%, p = 0.020). We conclude that cilostazol appears to have an inhibitory effect on intimal proliferation after directional coronary atherectomy and may reduce restenosis.