Lesions In Small Coronary Arteries Research Articles

Procedural characteristics and cardiovascular outcomes in patients undergoing drug-coated balloon angioplasty for de novo lesions in large coronary arteries: an observational study.

Limited data exist regarding drug-coated balloon (DCB) treatment in de novo large coronary arteries. We sought to demonstrate procedural characteristics, residual stenosis, and clinical outcomes following DCB angioplasty for de novo lesions in large versus small coronary arteries. The study included 184 consecutive patients with 223 de novo coronary lesions undergoing paclitaxel DCB angioplasty between January 2019 and August 2020, who were divided according to whether the DCB diameter was ≥ 3.0mm (large group, n = 58) or < 3.0mm (small group, n = 125). The large group had a higher proportion of acute coronary syndrome more commonly with ostial, bifurcation, and calcified lesions in large vessels and received lesion preparation with more frequent use of scoring or cutting balloons and atherectomy devices compared to the small group. Postprocedural angiographic diameter stenosis was smaller in the large group compared to the small group (31% [22-37] vs. 35% [26-42], p = 0.032), and intravascular ultrasound revealed no significant difference in postprocedural area stenosis between the groups (66.2 ± 7.7% vs. 67.9 ± 7.8%; p = 0.26). The median follow-up duration was 995days. The incidence of a composite of all-cause death, myocardial infarction, stroke, or target lesion revascularization was similar between the groups (log-rank p = 0.41) and was influenced by the presence of acute coronary syndrome and anemia but not by DCB diameter. The rate of cardiovascular outcomes after DCB treatment was comparable in de novo large and small coronary arteries. Notably, well-planned lesion preparation with intravascular imaging guidance was prevalent in large vessels.

Long-term benefits of drug-coated balloons for coronary artery revascularization.

Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) represents the treatment of choice for the majority of patients with coronary artery disease. While currently available DES, in addition to physiological support, has failed to show the non-inferiority to coronary artery bypass grafting (CABG) in terms of cumulative incidence of clinical events over the short-term follow-up. Studies have also shown that DES is associated with an increased risk of target vessel revascularization compared to CABG after long-term follow-up. Drug-coated balloons (DCB) have been shown to provide clinically significant benefits in the management of in-stent restenosis and diffuse coronary artery disease, as well as small coronary artery lesions. The aim of this review was to describe the inherent technical limitations of DES and highlight the potential advantages of PCI with DCB for long-term outcomes and potentially demonstrate its non-inferiority to CABG. Currently, ongoing studies will provide more information and help to understand if a blended therapy of DCB+DES can match the performance of CABG in the need for revascularization in more complex patients.

Response to pre-dilatation with POBA can predict target lesion revascularization after DCB angioplasty for de novo small coronary artery lesions.

ObjectiveTo assess the determinants of target lesion revascularization (TLR) after drug-coated balloon (DCB) angioplasty for de novo small coronary artery lesions.MethodsThis retrospective study enrolled consecutive lesions from patients that were in a stable condition and had undergone successful DCB treatment for de novo small coronary artery lesions. The study endpoint was TLR and major adverse cardiac events at 12 months.ResultsA total of 68 patients with 83 lesions were enrolled in the study. Of these, 11 (13.3%) lesions required TLR. Mean ± SD pre-dilatation balloon diameters were similar in the non-TLR (2.33 ± 0.72 mm) and TLR (2.18 ± 0.36 mm) groups. A comparison of the two groups showed that post/pre-lumen area ratio during pre-dilatation (%) by plain old balloon angioplasty (POBA) was significantly and negatively associated with TLR and the optimal cut-off point was 170%. Cox proportional hazard and multivariate regression analyses showed that post/pre-lumen area ratio was the only independent predictor of TLR (hazard ratio 0.9318; 95% confidence interval 0.9001, 0.9645).ConclusionGreater pre-dilatation using POBA, assessed as the post/pre-lumen area ratio, may be independently associated with a lower 12-month TLR rate in patients undergoing DCB angioplasty for de novo small coronary lesions.

One-year clinical outcomes in patients with very small coronary artery disease treated with drug-eluting stents: An observational study in the Indian population

Percutaneous coronary intervention (PCI) in very small vessel coronary arteries is challenging due to adverse short-term as well as long-term outcomes. This single-arm, open-label, observational study assessed 1-year clinical outcomes of drug-eluting stents (DES) in Indian patients undergoing PCI for symptomatic very small-calibre coronary artery disease. It enrolled 66 Indian patients with 74 very small coronary artery lesions (reference vessel diameter: ≥2.0 and ≤ 2.25 mm); eligible for implantation with 2.25 mm DES. The primary endpoint of major adverse cardiovascular events (MACE) was 3.0% indicating favourable 1-year clinical outcomes of DES in very small coronary artery lesions in Indian patients.

Drug-coated balloon treatment for nonsmall de-novo coronary artery disease: angiographic and clinical outcomes.

Although drug-coated balloons (DCBs) are established for de-novo lesions in small coronary arteries, the impact of DCB treatment according to the reference vessel diameter (RVD) remains poorly defined. This study aimed to evaluate the angiographic and long-term clinical outcomes of DCB treatment for de-novo coronary lesions according to RVD. A total of 227 patients were retrospectively enrolled and stratified according to an RVD >2.5 mm [nonsmall vessel disease (NSVD) group, n = 100] and ≤2.5 mm [small vessel disease (SVD) group, n = 127]. The primary endpoint was late lumen loss (LLL) at a 6-month follow-up, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization and target vessel thrombosis). The LLL among the 206 patients (90.8%) returning for scheduled angiography at 6 month was similar (NSVD, 0.03 ± 0.22 mm vs. SVD, 0.06 ± 0.25 mm; P = 0.384). TVF was also comparable in both groups at a median follow-up of 3.4 years (NSVD, 7.0 vs. SVD, 7.9 %; P = 0.596). At baseline, there were numerically more dissections in the SVD group compared to the NSVD group (47.2 vs. 35.0 %; P = 0.064); however, most of these had disappeared in both groups at a 6-month follow-up. In a multivariable analysis, the presence of dissection was not associated with LLL or TVF in either group. The safety and efficacy of DCB treatment for de-novo coronary lesions, in terms of LLL and TVF, was unrelated to RVD.

Efficacy of everolimus-eluting stent implantation in patients with small coronary arteries (≤2.5 mm): outcomes of 3-year clinical follow-up

Previous studies have demonstrated that patients with small coronary artery lesions are at increased risk for late cardiac events after percutaneous coronary intervention. It remains uncertain whether second-generation drug-eluting stents have an advantage over first-generation drug-eluting stents in patients with small vessel lesions. Our aim was to compare in the 3-year clinical impact between second-generation everolimus-eluting stents (EES) and first-generation sirolimus-eluting stents (SES) in small vessel lesions. Four-hundred forty-four patients with small vessel lesions defined as reference diameter <2.5mm were treated with EES (237 patients, 265 lesions) or SES (207 patients, 220 lesions) and completed 3-year follow-up. We compared the major adverse clinical events (MACE) between the two groups. EES had no significant impact on the MACE rate compared with SES (4.6 vs. 7.2%, p=0.14). No significant differences were observed in the individual components of cardiac death (1.7 vs. 1.9%, p=0.78), myocardial infarction (1.3 vs. 3.4%, p=0.12), and ischemia-driven target lesion revascularization (2.3 vs. 4.6%, p=0.13) in EES and SES, respectively. Stent thrombosis, however, was significantly less in the EES group than in the SES group (0.7 vs. 3.4%, HR: 0.53, 95% CI 0.38-0.88, p<0.05). EES implantation did not significantly impact 3-year MACE rates compared to SES implantation in small vessel lesions. A significant reduction in the overall rate of stent thrombosis was observed in recipients of EES. While the SES group showed increasing rates of late and very late thrombosis, the EES group did not. EES offers a safe and effective treatment for small vessel lesions.

Treatment of small coronary arteries with a paclitaxel-coated balloon catheter in the PEPCAD I study: are lesions clinically stable from 12 to 36 months?

The one-year outcome of lesions in small coronary arteries by using a paclitaxel-iopromide-coated (3 µg/mm²) balloon catheter (DCB) has yielded good six-month angiographic and one-year clinical data. We now report the three-year clinical follow-up. One hundred and twenty patients with >70% stenoses <22 mm in length in small coronary vessels (vessel diameter: 2.25-2.8 mm) were treated with the DCB. The primary endpoint was angiographic in-segment late lumen loss. The secondary endpoints encompassed all other angiographic and clinical data up to three years post intervention. In total 82/120 (68.3%) patients with a vessel diameter of 2.35±0.19 mm were treated with the DCB only, and 32/120 (26.7%) patients required additional bare metal stent (BMS) deployment. Both the 12- and 36-month major adverse cardiac event rates were 5/82 (6.1%) for DCB only and 12/32 (37.5%) for DCB+BMS, primarily due to the need for target lesion revascularisation in 4/82 (4.9%) patients and 9/32 (28.1%) (p<0.001) patients, respectively. Total MACE rate after 36 months was 18/120 (15%; intention-to-treat). Treatment of small vessel coronary artery disease with a paclitaxel-iopromide-coated balloon exhibited good six-month angiographic and one-year clinical data that persisted during the three-year follow-up period. Randomised trials will clarify its role as an alternative to drug-eluting stents in the treatment of small vessel coronary artery disease. (ClinicalTrials.gov Identifier: NCT00404144).

GW24-e0345 Drug-eluting Balloons for de novo coronary artery disease: Pooled Angiographic and Clinical Data

ObjectivesCurrent evidence regarding the successof drug-eluting balloons (DEBs) for de novo coronary artery disease is insufficient for formulating formal recommendations. This study aimed to evaluate the effectiveness of DEBs by...

Outcomes of Overlapping Heterogeneous Drug‐Eluting Stents Versus Homogeneous Drug‐Eluting Stents for Diffuse Lesions in Small Coronary Arteries

To investigate the outcomes of overlapping drug-eluting stenting (DES) in small and diffuse lesions. Clinical outcomes of overlapping heterogeneous versus homogeneous DES of diffuse lesions (requiring ≥ 30 mm of length) in small coronary arteries (requiring ≤ 2.75 mm of diameter) are unknown. From January 2005 to December 2009, there were 99 patients with diffuse lesions in small coronary arteries receiving overlapping heterogeneous DES, and 558 patients receiving overlapping homogeneous DES at our institution. The clinical end-point of the study included in-hospital and 12-month major adverse cardiac events (death, nonfatal myocardial infarction, and target vessel revascularization (TVR). There were no statistically significant differences between overlapping heterogeneous and homogeneous DES groups in-hospital (2.0% vs. 1.4%, respectively; P = 0.66) and 12-month (9.1% vs. 9.3%, respectively; P = 0.94) major adverse cardiac events. After adjustment, no significant differences for major adverse cardiac events were noted, but the rate of nonfatal myocardial infarction was lower in overlapping homogeneous DES group (odds ratio: 4.20, P = 0.03). In this analysis, there were no significant differences in major adverse cardiac events between the 2 types of overlapping DES for diffuse lesions in small coronary arteries, except for higher nonfatal myocardial infarction in overlapping heterogeneous DES.

New Set of Intravascular Ultrasound-Derived Anatomic Criteria for Defining Functionally Significant Stenoses in Small Coronary Arteries (Results from Intravascular Ultrasound Diagnostic Evaluation of Atherosclerosis in Singapore [IDEAS] Study)

We sought to determine the intravascular ultrasound-derived anatomic criteria for functionally significant lesions in small coronary arteries with a reference segment diameter <3 mm. A fractional flow reserve (FFR) of <0.75, as determined by pressure wire using high-dose (100 to 150 microg) intracoronary adenosine, was used as the reference standard for functional significance. For the 94 patients/lesions involved in the present study, the average reference vessel diameter was 2.72 mm. The FFR was <0.75 in 38 patients (40.4%) and > or =0.75 in 56 patients (59.6%). Logistic regression analysis identified the minimal lumen area, plaque burden, and lesion length as the 3 most important determinants of the FFR. Using classification and regression tree analysis, the best cutoff values for these determinants to discriminate a FFR of <0.75 versus > or =0.75 were a minimal lumen area of < or =2.0 mm(2) (sensitivity 82.35%, specificity 80.77%), plaque burden of > or =80% (sensitivity 87.9%, specificity 78.9%), and lesion length of > or =20 mm (sensitivity 63.6%, specificity 78.9%). A significant increase was found in the area under the receiver operating characteristic curve of the combined parameters (minimal lumen area plus plaque burden plus lesion length) compared to the plaque burden (p = 0.014) and other individual parameters (p <0.001). In conclusion, we found that intravascular ultrasound-derived anatomic criteria are able to predict the functional significance of intermediate lesions in small coronary arteries. A minimal lumen area of < or =2.0 mm(2), plaque burden of > or =80%, and lesion length of > or =20 mm predicted a FFR of <0.75 with good sensitivity and specificity.

Percutaneous coronary intervention of patients with complex small coronary artery lesion unsuitable for coronary artery bypass graft

To investigate the safety and efficacy of percutaneous coronary intervention (PCI) in patients with low left ventricular ejection fraction (LVEF) and complex small coronary artery lesions. Complete or partial post-PCI revascularization of coronary artery was employed in 16 patients with a low LVEF and complex small coronary artery lesions who were unsuitable for CABG (coronary artery bypass grafting). All cases were observed with regards to immediate success rate of operation, complication, hospitalization duration, improvement of cardiac function and LVEF and major adverse cardiac events (including cardiac death, myocardial infarction and target lesion revascularization) at 12 months post-operation. All cases were successfully treated without death and severe complications while the hospitalization duration was (11 +/- 5) days. The follow-up survey at 12 months post-operation showed that no major adverse cardiac event occurred, the post-operative improvement of cardiac function was from III - IV grade to I - II grade, the improvement of LVEF was from 25% - 45% [(29 +/- 8)%] to 32% - 48% [(37 +/- 7)%], left ventricular end diastolic diameter (LVDd) was shortened from 52 - 79 (66 +/- 11) mm to 49 - 68 (58 +/- 8) mm. The reexamination of 14 cases by coronary angiography at 12 months post-operation showed that there was no intra-stent thrombosis while 20% - 40% intra-stent restenosis occurred in 2 cases. For patients with a low LVEF and complex small coronary artery lesions, PCI is a safe and effective method to lower the mortality rate of CHD patients with heart failure and improve the long-term patient prognosis.

Treatment of small coronary arteries with a paclitaxel-coated balloon catheter

Treatment of lesions in small coronary arteries by percutaneous transluminal coronary intervention is limited by a high recurrence rate. We assessed the use of a paclitaxel-coated balloon in this indication. One-hundred eighteen patients with stenoses in small coronary vessels were treated by a paclitaxel-coated balloon (3 microg/mm(2)). The main inclusion criteria encompassed diameter stenosis of > or =70% and < or =22 mm in length with a vessel diameter of 2.25-2.8 mm. Follow-up angiography was performed at scheduled 6-month post-intervention or whenever driven by clinical or electrocardiographic signs of ischemia. The primary endpoint was angiographic in-segment late lumen loss. Eighty-two of 118 patients (70%) with a vessel diameter of 2.35 +/- 0.19 mm were treated with the drug-coated balloon only, while 32 patients required additional stent deployment. The mean in-segment late lumen loss was 0.28 +/- 0.53 mm. In patients treated with the drug-coated balloon only, the in-segment late lumen loss was 0.16 +/- 0.38 mm. At 12 months, the rate of major adverse cardiac events was 15% which was primarily due to the need for target lesion revascularization in 14 patients (12%). In those with additional bare metal stent implantation geographical mismatch between coated-balloon dilatation and stent implantation was significantly associated with the occurrence of restenosis. Treatment of coronary stenosis in small coronary vessels with the paclitaxel-coated balloon was well tolerated. It may offer an alternative to the implantation of a drug-eluting stent (ClinicalTrials.gov Identifier: NCT00404144).

Gender-Specific Outcomes After Sirolimus-Eluting Stent Implantation

We examined the impact of gender on outcomes of patients undergoing percutaneous coronary intervention using sirolimus-eluting stents (SES). Although gender-specific differences in outcome after implantation of bare-metal stents (BMS) have been described, there are no data assessing outcomes of women treated with SES. We performed a patient-level pooled analysis from 4 randomized SES versus BMS trials (RAVEL [Randomized Comparison of a Sirolimus-Eluting Stent with a Standard Stent for Coronary Revascularization], SIRIUS [SIRolImUS-coated Bx Velocity balloon expandable stent in the treatment of patients with de novo coronary artery lesions], E-SIRIUS [Sirolimus-eluting stents for treatment of patients with long atherosclerotic lesions in small coronary arteries], and C-SIRIUS [Canadian study of the sirolimus-eluting stent in the treatment of patients with long de novo lesions in small native coronary arteries]) and analyzed outcomes as a function of gender. Of 1,748 patients, 1,251 were men and 497 were women. A total of 878 patients were randomized to SES (629 men and 249 women), and 870 patients were randomized to BMS (622 men and 248 women). Compared with men, women were older and more frequently had diabetes mellitus, hypertension, and congestive heart failure. Although overall clinical outcomes were similar in both genders, treatment with SES was associated with significant (p < 0.0001) reductions in rates of in-segment binary restenosis both in women (6.3% vs. 43.8%) and in men (6.4% vs. 35.6%), resulting in a significant reduction in 1-year major adverse cardiac events, driven by a lower incidence of target lesion revascularization/target vessel revascularization in both genders. By multivariable analysis, female gender was not an independent predictor of in-segment binary restenosis or clinical outcomes regardless of stent type. In this analysis, despite less favorable baseline clinical and angiographic features in women compared with men, the angiographic and clinical benefits of SES were independent of gender.

Abstract 2150: A European and Canadian Multicenter Randomized, Double-Blind Trial of the Sirolimus-Eluting Stent (SES) in Patients with De Novo Native Coronary Artery Lesions (NEW-SIRIUS): 5-Year Clinical Outcomes

Background : NEW-SIRIUS is the pooled analysis of the E-SIRIUS (n=352) and C-SIRIUS (n=100) studies, respectively, performed in Europe and Canada. Identical in design, these are multicenter randomized, double-blind trials examining the safety and efficacy of the sirolimus-eluting stent (SES) vs. an identical bare-metal stent (BMS) in 452 patients to treat de novo native long lesions in small coronary arteries, with adjunctive clopidogrel for only 2 months. Methods : The primary endpoint was in-stent minimum lumen diameter (MLD) at 8-month follow-up. Among the secondary endpoints were major adverse cardiac events(MACE) at 1, 6, 9 and 12 months, and annually up to 5 years post-procedure, as well as target lesion revascularization (TLR), target vessel revascularization (TVR) and protocol-defined stent thrombosis. Results : At 8 months, the MLD was 2.27±0.47mm in the SES vs. 1.36±0.66 mm in the BMS (p &lt; 0.001). The binary in-lesion restenosis rate was 5.1% in the SES vs. 44.2% in the BMS (p &lt; 0.001). At 4 years, there was a significantly lower incidence of MACE (SES: 15.1% vs BMS: 33.9%, p &lt; 0.001), primarily driven by a significant difference in clinically-driven TLR rates (SES: 7.1% vs. BMS: 26.0%, p &lt; 0.001). A subgroup analysis in diabetic patients (45 SES, 60 BMS) demonstrated that the in-stent MLD was larger in SES than in BMS (2.20±0.47 vs 1.14±0.64 mm, p &lt; 0.001) and the binary in-lesion restenosis rate was reduced from 56.1% (BMS) to 10.0% (RRR: 82.2%, p &lt; 0.001) at 8 months. At 4 years, the freedom from MACE in diabetic patients was 80.0% in the SES vs. 61.7% in the BMS (p = 0.031), again mainly driven by an improved freedom from clinically driven-TLR (SES: 90.8% vs. BMS: 66.9%, p=0.005), with no evidence of a late catch-up effect. Conclusion : Up to 4 years, SES were superior to BMS in the total cohort as well as in the diabetic subgroup without evidence of a late catch-up. Five-year follow-up data, including antiplatelet therapies utilization and a diabetic subgroup analyses will be available by July 2007 and presented.

Prospective randomized study of the restenotic process in small coronary arteries using a Carbofilm™ coated stent in comparison with plain old balloon angioplasty:

The optimal interventional approach to treat lesions in small coronary arteries is still undetermined and controversial. This randomized, multicenter trial was designed to compare the 6-months restenosis and clinical event rates in two treatment groups: balloon angioplasty as a primary strategy and provisional stenting versus primary implantation of a carbon coated stent (Carbosten). At 6 months the angiographic restenosis rate was significantly lower for the stented patients (11.6%) as compared to the balloon angioplasty patients (32.2%). However this advantage in restenosis rate did not translate into a clinical benefit in respect to target vessel revascularization rates. This trial demonstrated a remarkably low 6-months restenosis rate for lesions in small (<2.8 mm) coronary arteries treated with Carbosten implantation that is comparable to the rates found after drug eluting stent implantation and was significantly better in comparison to balloon angioplasty alone.

Factors predictive of cardiac events and restenosis after sirolimus‐eluting stent implantation in small coronary arteries

Predictors of cardiac events and restenosis after sirolimus-eluting stent (SES) implantation in small coronary arteries were evaluated. Although SES implantation has markedly reduced the risk of restenosis, small vessel disease remains a major cause of SES failure. We prospectively investigated the factors predictive of cardiac events and restenosis in 1,092 consecutive patients who received SES implantation for 1,269 lesions in small coronary arteries (< or = 2.8 mm). Follow-up angiography at 6 months was performed in 751 patients with 889 lesions (follow-up rate 70.3%). Restenosis (diameter stenosis > or = 50%) was angiographically documented in 65 patients with 77 lesions (8.7%): 55 focal (71.4%), 8 diffuse (10.4%), 2 diffuse proliferative (2.6%), and 12 total (15.6%). Lesion length, stent length, reference artery size, and in-stent restenotic lesions were univariate predictors of restenosis. By multivariate analysis, lesion length (OR 1.04; 95% CI 1.02-1.05; P < 0.001) and in-stent restenotic lesions (OR 3.38; 95% CI 1.80-6.35; P < 0.001) were significant independent predictors of restenosis. During follow-up (23.2 +/- 7.9 months), there were 17 deaths (5 cardiac and 12 noncardiac), 5 nonfatal Q-wave myocardial infarctions, and 42 target lesion revascularizations. The cumulative probability of survival without major adverse cardiac events (MACE) was (96.6 +/- 0.6)% at 1 year and (95.1 +/- 0.7)% at 2 years. In multivariate analysis, lesion length (HR 1.04; 95% CI 1.01-1.07; P = 0.004) and in-stent restenotic lesions (HR 3.29; 95% CI 1.58-6.86; P = 0.001) were independently related to MACE. SES implantation in small coronary arteries is safe and effective, with lesion length having a major impact on restenosis and MACE.

Comparison of Effectiveness of Bare Metal Stents Versus Drug-Eluting Stents in Large (≥3.5 mm) Coronary Arteries

Drug-eluting stents (DESs) are superior to bare metal stents (BMSs) in decreasing restenosis rates across a wide range of patient and lesion subsets. However, widespread utilization of DESs raises concerns with regard to risks of prolonged dual antiplatelet therapy, the potential for late adverse events such as late thrombosis, and cost. Vessel diameter and lesion length have been previously identified as predictors for restenosis for DESs and BMSs. This study compared the clinical outcomes of DESs versus BMSs in large coronary arteries (> or =3.5 mm). A cohort of 233 patients who underwent single-vessel angioplasty with DES implantation in large vessels was compared with 233 propensity-matched patients who received BMSs in vessels with similar reference vessel diameters. Clinical outcomes at 30 days, 6 months, and 1 year were compared between groups. Baseline clinical and procedural characteristics were similar. Target lesion revascularization and target vessel revascularization rates and the incidence of major adverse cardiac events were low and comparable between the 2 groups at all follow-up intervals. At 1 year, the primary outcome occurred in 8.5% of patients with DESs and 7.7% of patients with BMSs (p = 0.80). There were no episodes of subacute stent thrombosis or late thrombosis in either group. In conclusion, implantation of DESs in large coronary arteries confers no additional benefit compared with BMSs, and the 2 approaches are associated with equally favorable clinical outcomes at 1 year.

Is Stent Underexpansion the Main Cause of In-Stent Restenosis after Sirolimus-Eluting Stent Implantation?: An Intravascular Ultrasound Study

Background and Objectives:Intravascular ultrasound (IVUS) can be useful for assessing the causes of in-stent restenosis (ISR) after sirolimus-eluting stent (SES) implantation. We used IVUS to evaluate the causes of ISR after SES implantation. Subjects and Methods:SES implantation was performed in 502 patients with 670 coronary lesions. Of these patients, 27 patients had angiographic ISR in 28 lesions. We evaluated the patterns of ISR and we wanted to elucidate the possible mechanism of ISR after SES implantation with using IVUS analysis. Results:The ISR pattern was focal in 26 lesions, and diffuse in 2 lesions, including 1 total occlusion. When analyzing the 21 IVUS-applicable lesions, stent underexpansion [the minimal stent cross-sectional area (CSA) was <5 mm and it was <4.5 mm in the cases of small coronary arteries (reference vessel diameter <2.8 mm)] was observed in 10 lesions (48%). Stent fracture (defined as non-visualization of the struts on IVUS at the restenotic segments) and edge restenosis was identified in the 3 (14%) and 3 lesions (14%), respectively. Except for edge stenosis, stent underexpansion was observed in 55% of the intra-stent restenotic lesions and it was more prominent in the small coronary arteries (7/8 small coronary artery lesions). Stent underexpansion, stent fracture or edge restenosis were not related to the 7 ISR lesions (33%) in which profound intimal hyperplasia within the stent occurred. Conclusion:Our observation of ISR after SES implantation with using IVUS showed that most ISR lesions have mechanical problems, especially stent underexpansion. However, one third of the ISR lesions were associated with profound intimal hyperplasia within the stent. (Korean Circulation J 2007;37:58-63)

Drug-Eluting Stents

“Does it make economic sense to completely abandon a therapy that works well for 85% to 90% of the population for a new therapy costing four times as much to treat a transient health condition with no impact on either death or myocardial infarction?” J.M. Brophy and L.J. Erickson1 Since Andreas Gruntzig performed the first percutaneous coronary intervention (PCI) in 1977,2 the cost-effectiveness of this procedure has engendered major controversy. Debates have erupted over the clinical value and cost-effectiveness of each new device or therapy that has become available. Controversies have arisen regarding the cost of atherectomy, bare metal stents (BMS), brachytherapy, distal protection devices, glycoprotein IIb/IIIa inhibitors, and intravascular ultrasound.3–6 Drug-eluting stents (DES) are the most recent devices to have their cost scrutinized.7–12 Response by Ryan and Cohen p 1754 Balloon angioplasty is associated with restenosis rates of 30% to 40%, whereas PCI with BMS is associated with rates of 20% to 30%,13,14 and PCI with DES is associated with rates in the single digits.15,16 My colleagues and I pooled the results of 11 DES trials involving >5000 patients using a hierarchical Bayesian random-effects model.17 We found that, compared with BMS, DES reduce angiographic restenosis from 29.3% to 8.9% (Table 1 and Figure 1). There was no difference between DES and BMS in terms of mortality (0.9% versus 0.9%, respectively) or myocardial infarction (2.7% versus 2.9%, respectively). There was a suggestion that restenosis was less with sirolimus-eluting stents (SES) compared with polymeric paclitaxel-eluting stents (PES) (6.2% for SES versus 36.9% for BMS; 7.1% for PES versus 23.5% for BMS), a finding that was subsequently identified in another meta-analysis.18 View this table: TABLE 1. Clinical Events and Restenosis Rates in Randomized Clinical Trials Investigating DESs Figure 1. Forest plot comparing rates of angiographic restenosis for …

Comparison of the effectiveness of sirolimus‐ and paclitaxel‐eluting stents for small coronary artery lesions

The sirolimus-eluting stent (SES) and the paclitaxel-eluting stent (PES) reduce restenosis in small coronary artery lesions. However, it is not clear which of these stents is superior in terms of clinical outcomes. The authors retrospectively examined 197 patients with 245 de novo small coronary artery lesions (<or=<or=2.75 mm) that were treated with either the SES (156 lesions) or the PES (89 lesions). Six-month angiographic restenosis rates and the 9-month target lesion revascularization (TLR) rates were compared between the two groups. In terms of baseline clinical and angiographic parameters, the two groups well matched together. Six-month angiographic follow-up was performed on 170 patients (86.3%), comprising 135 SES lesions (86.5%) and 76 PES lesions (85.4%). At 6-month angiographic follow-up, the late lumen loss was less in the SES group than in the PES group (0.29 +/- 0.42 vs. 0.69 +/- 0.63 mm, P < 0.01). Therefore, the SES group showed a lower rate of angiographic restenosis than the PES group (6.7% vs. 27.7%, P < 0.01). At 9 months there were no deaths or myocardial infarctions in either group. The 9-month TLR rate was lower in the SES group than in the PES group (3.3% vs. 14.4%, P < 0.01). The Kaplan-Meier estimate of freedom from TLR at 9 months was 96.7% for the SES patients and 86.5% for the PES patients (P < 0.01). The SES treatment may be superior to the PES treatment in terms of long-term clinical and angiographic outcomes in patients with small coronary artery lesions.