Randomized comparison of coronary stenting with optimal balloon angioplasty for treatment of lesions in small coronary arteries

Comparison of Clinical Outcomes Among Various Percutaneous Coronary Intervention Strategies for Small Coronary Artery Disease

It remains unclear which percutaneous coronary intervention (PCI) strategy is the most preferable in patients with small-vessel coronary artery disease (CAD). We sought to evaluate the clinical efficacy of various PCI strategies for patients with small-vessel CAD through a network meta-analysis of randomized controlled trials (RCTs). We searched multiple databases for RCTs investigating the efficacy of the following PCI strategies for small-vessel CAD (<3 mm in diameter): drug-coated balloons (DCB), early-generation paclitaxel-eluting stents and sirolimus-eluting stents (SES), newer-generation drug-eluting stents (DES), bare-metal stents (BMS), cutting balloon angioplasty, and balloon angioplasty (BA). The primary outcome was the trial-defined major adverse cardiovascular events (MACE), mostly defined as a composite of death, myocardial infarction, and revascularization. The secondary outcomes included each component of MACE and angiographic binary restenosis. We performed a sensitivity analysis for RCTs without BMS or first-generation DES. Our search identified 29 eligible RCTs, including 8,074 patients among the 8 PCI strategies. SES significantly reduced MACE compared with BA (hazard ratio 0.23, 95% confidence interval 0.10 to 0.54) with significant heterogeneity (I2 = 55.9%), and the rankogram analysis showed that SES was the best. There were no significant differences between DCB and newer-generation DES in any clinical outcomes, which was consistent in the sensitivity analysis. BMS and BA were ranked as the worst 2 for most clinical outcomes. In conclusion, SES was ranked as the best for reducing MACE. There were no significant differences in clinical outcomes between DCB and newer-generation DES. BMS and BA were regarded as the worst strategies for small-vessel CAD.

Drug-coated balloon: an effective alternative to stent strategy in small-vessel coronary artery disease-a meta-analysis

Background

Small-vessel coronary artery disease (CAD) is frequently observed in coronary angiography and linked to a higher risk of lesion failure and restenosis. Currently, treatment of small vessels is not standardized while having drug-eluting stents (DES) or drug-coated balloons (DCBs) as possible strategies. We aimed to conduct a meta-analytic approach to assess the effectiveness of treatment strategies and outcomes for small-vessel CAD.

Methods

Comprehensive literature search was conducted using PubMed, Embase, MEDLINE, and Cochrane Library databases to identify studies reporting treatment strategies of small-vessel CAD with a reference diameter of ≤3.0 mm. Target lesion revascularization (TLR), target lesion thrombosis, all-cause death, myocardial infarction (MI), and major adverse cardiac events (MACE) were defined as clinical outcomes. Outcomes from single-arm and randomized studies based on measures by means of their corresponding 95% confidence intervals (CI) were compared using a meta-analytic approach. Statistical significance was assumed if CIs did not overlap.

Results

Thirty-seven eligible studies with a total of 31,835 patients with small-vessel CAD were included in the present analysis. Among those, 28,147 patients were treated with DES (24 studies) and 3,299 patients with DCB (18 studies). Common baseline characteristics were equally distributed in the different studies. TLR rate was 4% in both treatment strategies [0.04; 95% CI 0.03-0.05 (DES) vs. 0.03-0.07 (DCB)]. MI occurred in 3% of patients receiving DES and in 2% treated with DCB [0.03 (0.02-0.04) vs. 0.02 (0.01-0.03)]. All-cause mortality was 3% in the DES group [0.03 (0.02-0.05)] compared with 1% in the DCB group [0.01 (0.00-0.03)]. Approximately 9% of patients with DES developed MACE vs. 4% of patients with DCB [0.09 (0.07-0.10) vs. 0.04 (0.02-0.08)]. Meta-regression analysis did not show a significant impact of reference vessel diameter on outcomes.

Conclusion

This large meta-analytic approach demonstrates similar clinical and angiographic results between treatment strategies with DES and DCB in small-vessel CAD. Therefore, DES may be waived in small coronary arteries when PCI is performed with DCB.

Clinical outcomes of percutaneous coronary intervention for de novo lesions in small coronary arteries: A systematic review and network meta-analysis

Background

Percutaneous coronary intervention (PCI) has a well-established role in revascularization for coronary artery disease. We performed network meta-analysis to provide evidence on optimal intervention strategies for de novo lesions in small coronary arteries.

Materials and methods

Enrolled studies were randomized clinical trials that compared different intervention strategies [balloon angioplasty (BA), biolimus-coated balloon (BCB), bare-metal stent (BMS), new-generation drug-eluting stent (New-DES), older generation sirolimus-eluting stent (Old-SES), paclitaxel-coated balloon (PCB), and paclitaxel-eluting stent (PES)] for de novo lesions in small coronary arteries. The primary outcome was major adverse cardiac events (MACE).

Results

A total of 23 randomized clinical trials comparing seven intervention devices were analyzed. In terms of the primary outcome, New-DES was the intervention device with the best efficacy [surface under the cumulative ranking curve (SUCRA), 89.1%; mean rank, 1.7], and the Old-SES [risk ratio (RR), 1.09; 95% confidence interval (CI), 0.45–2.64] and PCB (RR, 1.40; 95% CI, 0.72–2.74) secondary to New-DES, but there was no statistically significant difference between these three intervention devices. All DES and PCB were superior to BMS and BA for MACE in both primary and sensitivity analysis. For secondary outcomes, there was no association between all-cause mortality and myocardial infarction (MI) with any intervention strategy, and additionally, the findings of target lesion revascularization (TLR) were similar to the primary outcomes.

Conclusion

Paclitaxel-coated balloon yielded similar outcomes to New-DES for de novo lesions in small coronary arteries. Therefore, this network meta-analysis may provide potential support for PCB as a feasible, effective, and safe alternative intervention strategy for the revascularization of small coronary arteries.

Systematic review registration

[https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42022338433].

Drug-Coated balloons vs drug-eluting stents for the treatment of small coronary artery disease: A meta-analysis of randomized trials

OBJECTIVES AND BACKGROUND

There is conflicting evidence about the effects of drug-coated balloons (DCB) compared with drug-eluting stents (DES) in patients with native small vessel coronary artery disease (CAD).

METHODS

The PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases and main international conference proceedings were searched for randomized controlled trials (RCT) comparing DCB versus DES in patients with native small vessel CAD. Data were pooled by meta-analysis using a random-effects model. The primary endpoint was target vessel revascularization (TVR). Secondary clinical endpoints were: myocardial infarction (MI), target lesion revascularization (TLR), all-cause death, cardiac death, and stent thrombosis or target vessel thrombosis. Secondary angiographic outcomes were: in-segment restenosis, in-segment percentage-diameter stenosis, in-segment late lumen loss, in-segment net luminal gain, and in-segment minimal lumen diameter.

RESULTS

Five trials enrolling 1,459 patients were included. Mean clinical follow-up was 10.2 months. The use of DCB, compared with DES, was associated with similar risk of TVR (odds ratio [OR]: 0.97; 95% confidence interval [CI] 0.56 to 1.68; p = .92), TLR (OR: 1.74; 95% CI: 0.57 to 5.28; p = .33), all-cause death (OR: 1.03; 95% CI: 0.14 to 7.48; p = .98), with a trend toward a lower risk of MI (OR: 0.49; 95% CI: 0.23 to 1.03; p = .06), and with significant lower risk of vessel thrombosis (OR: 0.12; 95% CI: 0.01 to 0.94; p = .04). DCB use was associated with similar risk of angiographic restenosis (OR: 1.12; 95% CI 0.69 to 1.84; p = .64), comparable late luminal loss (standardized mean difference (SMD): -0.18; 95% CI: -0.39 to 0.03; p = .09), while leading to significant higher percentage diameter stenosis (SMD: 0.27; 95% CI 0.12 to 0.41; p < .01) and smaller minimal luminal diameter (SMD: -0.52; 95% CI: -0.86 to -0.18; p = .003).

CONCLUSION

Compared with DES, the use of DCB for the treatment of native small vessel CAD is associated with similar TVR and restenosis and reduces the risk of vessel thrombosis, although DES implantation yields slightly better angiographic surrogate endpoints.

A multicenter randomized comparison of paclitaxel-coated balloon with plain balloon angioplasty in patients with small vessel disease

AIM

We investigated the efficacy and safety of using paclitaxel-coated balloon (PCB) to treat small vessel disease.

METHODS AND RESULTS

In this multicenter, prospective, randomized controlled trial, one-hundred and thirty-five patients with native coronary lesions in small vessels were randomized into a PCB group and plain balloon angioplasty (POBA) group at a ratio of 2:1. There were no differences in target vessel failure (TVF) that was defined as cardiac death or target vessel-related myocardial infarction or target lesion revascularization (TLR), between the two groups (3.4 vs. 10.3%; P = 0.20), and TLR was slightly lower in the PCB group (2.3%) than that in the POBA group (10.3%) during 24 weeks follow-up. The late lumen loss (LLL) was significantly lower in the PCB group (0.01 ± 0.31 vs. 0.32 ± 0.34 mm; P < 0.01) and late lumen enlargement (LLE) was more frequently observed in the PCB group (48 vs. 15%; P < 0.01) by angiographic follow-up after 24 weeks. There were no cases of death, myocardial infarction, thrombosis and reocclusion in either group.

CONCLUSIONS

This study was not able to demonstrate superiority of PCB compared with POBA.

The outcomes of patients with very small coronary artery disease treated with thin strut cobalt chromium bare metal stents: an observational study

BACKGROUND

Percutaneous coronary interventions (PCI) in coronary artery disease (CAD) with very small vessel diameters remains controversial and challenging. These lesions are usually more diffuse, calcified and tortuous. The usage of thin strut bare metal stents (BMS) with excellent crossing profiles in a very small caliber coronary lesions has increased the likelihood of procedural success.

OBJECTIVES

This observational study assessed the 9-month clinical outcomes in an 'all-comers' population with very small caliber CAD after implantation of thin strut cobalt chromium BMS.

METHODS

Thin strut cobalt chromium BMS implantation in a priori pre-defined subgroups was investigated in a non-randomized, international, multi-center 'all-comers' observational study. Primary end-point was the 9-month clinically driven target lesion revascularization (TLR) rate. Secondary end-points included the 9-month major adverse cardiac event (MACE) and procedural success rates. Data collection was done using an established electronic data acquisition form with built-in plausibility checks.

RESULTS

A total of 783 patients with a mean age of 70.4 ± 12.8 years were enrolled, 205 (26.2 %) of them had vessel diameters of 2.5 mm and smaller which was defined as CAD with very small reference vessel calibers. Older age and diabetics were associated with higher incidences of very small caliber vessels. The mean reference vessel diameter in the very small vessel group was 2.05 ± 0.27 mm and mean diameter for vessels >2.5 mm was 3.41 ± 0.55 mm. Pre-dilatation was performed more often in the very small vessel patients (52.2 vs. 42.2 %; p value 0.007). There was no difference in the overall technical success rates in very small vessel disease group (97.9 vs. 97.7 %). The 9-month TLR rate was 6.3 % for the very small vessels and 3.7 % for vessels >2.5 mm (p = 0.129). The 9-month and in-hospital MACE rates in the very small vessel group and patient with vessel diameters >2.5 mm were not significantly different (13.1 vs. 9.2 %; p = 0.1265 and 5.2 vs. 3.7 %; p = 0.349) respectively.

CONCLUSION

This study has demonstrated that the use of thin strut cobalt chromium BMS in very small vessel CAD was reasonably safe and efficacious in the context of 'real-world' practice.

Drug-eluting versus bare-metal stents in large coronary arteries of patients with ST-segment elevation myocardial infarction: findings from the ICAS registry

BACKGROUND AND PURPOSE

There are a few retrospective subgroup analyses or registries of large-vessel (≥ 3.5mm) stenting. We investigated clinical outcomes of patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES) and bare-metal stents (BMS) in large coronary vessels.

METHODS AND SUBJECTS

Of 1100 STEMI patients registered in the Ibaraki Cardiovascular Assessment Study (ICAS) multicenter registry from April 2007 to June 2012 who underwent PCI, we enrolled 454 patients (65.8 ± 12.7 years old, 81% male) with ≥ 3.5-mm stents. We excluded 53 patients with cardiogenic shock or left main trunk lesions. The remaining 401 patients were divided into Group-D, PCI with DES (n = 184), and Group-B, PCI with BMS (n = 217). Propensity score analysis matched 1:1 according to treatment with DES (n = 101) or with BMS (n = 101). We evaluated major adverse cardiac and cerebrovascular events (MACCE) and incidence of stent thrombosis (ST). MACCE was defined as all-cause death, myocardial infarction (MI), target-vessel revascularization (TVR), or cerebrovascular accident (CVA).

ESSENTIAL RESULTS

During a mean follow-up period of 526 days, all-cause death, MI, CVA, MACCE, and ST were not significantly different in Group-D versus Group-B (all-cause death: 4.35% vs. 4.61%, p = 0.90; MI: 0% vs. 0%; CVA: 2.72% vs. 3.23%, p = 0.76; MACCE: 15.2% vs. 20.3%, p = 0.19; and ST: 0.0% vs. 1.38%, p = 0.11). After adjusting for age, insulin use, multivessel disease, intra-aortic balloon pump use, culprit lesions, and estimated glomerular filtration rate <60 ml/min/1.73 m(2), MACCE was not significantly different between the groups (odds ratio: 0.69; 95% CI: 0.40-1.23; p = 0.21). However, TVR was significantly lower in Group-D than Group-B in Kaplan-Meier analysis (p = 0.048) after propensity score matching.

PRINCIPAL CONCLUSION

There was no advantage to using a DES in large vessels for preventing a hard endpoint, whereas DES use resulted in a significant reduction in TVR in the patients with STEMI in this registry.

New technologies aimed at percutaneous intervention in the small coronary artery

Percutaneous coronary intervention (PCI) of small vessels can be complicated by technically difficult access to the target lesion, an increased risk of major adverse cardiac events and in-stent restenosis requiring repeat revascularization. Conventional management of such lesions is with drug-eluting stent implantation; however, these have only partly attenuated the problem. In response, several medical device companies are competing to produce new technologies aimed at PCI in small coronary arteries. Such innovations include thin-strutted stents, stent-on-a-wire systems, drug-coated balloons, endothelial progenitor cell-catching stents and biodegradable stent systems. To date, none of these techniques have been sufficiently validated for use in small coronary arteries to justify a change in practice; however, small-vessel coronary artery disease is an increasingly common problem, and PCI of target lesions with reference vessel diameter <3.0 mm is likely to increase, especially in view of the increasing prevalence of diabetes, warranting further well-designed studies. The prospect of mounting a self-expandable biodegradable drug-eluting stent directly onto a guidewire could potentially be an exciting future development.

Drug-eluting versus bare-metal stents in large coronary arteries

BACKGROUND

Recent data have suggested that patients with coronary disease in large arteries are at increased risk for late cardiac events after percutaneous intervention with first-generation drug-eluting stents, as compared with bare-metal stents. We sought to confirm this observation and to assess whether this increase in risk was also seen with second-generation drug-eluting stents.

METHODS

We randomly assigned 2314 patients needing stents that were 3.0 mm or more in diameter to receive sirolimus-eluting, everolimus-eluting, or bare-metal stents. The primary end point was the composite of death from cardiac causes or nonfatal myocardial infarction at 2 years. Late events (occurring during months 7 to 24) and target-vessel revascularization were the main secondary end points.

RESULTS

The rates of the primary end point were 2.6% among patients receiving sirolimus-eluting stents, 3.2% among those receiving everolimus-eluting stents, and 4.8% among those receiving bare-metal stents, with no significant differences between patients receiving either drug-eluting stent and those receiving bare-metal stents. There were also no significant between-group differences in the rate of late events or in the rate of death, myocardial infarction, or stent thrombosis. Rates of target-vessel revascularization for reasons unrelated to myocardial infarction were 3.7% among patients receiving sirolimus-eluting stents, 3.1% among those receiving everolimus-eluting stents, and 8.9% among those receiving bare-metal stents. The rate of target-vessel revascularization was significantly reduced among patients receiving either drug-eluting stent, as compared with a bare-metal stent, with no significant difference between the two types of drug-eluting stents.

CONCLUSIONS

In patients requiring stenting of large coronary arteries, no significant differences were found among sirolimus-eluting, everolimus-eluting, and bare-metal stents with respect to the rate of death or myocardial infarction. With the two drug-eluting stents, similar reductions in rates of target-vessel revascularization were seen. (Funded by the Basel Cardiovascular Research Foundation and the Swiss National Foundation for Research; Current Controlled Trials number, ISRCTN72444640.).

Small coronary vessel angioplasty: outcomes and technical considerations

Small vessel (<3 mm) coronary artery disease is common and has been identified as independent predictor of restenosis after percutaneous coronary intervention. It remains controversial whether bare-metal stent (BMS) implantation in small vessels has an advantage over balloon angioplasty in terms of angiographic and clinical outcomes. Introduction of drug-eluting stent (DES) has resulted in significant reduction in restenosis and the need for repeat revascularization. Several DESs have been introduced resulting in varying reduction in outcomes as compared with BMS. However, their impact on outcomes in small vessels is not clearly known. It is expected that DES could substantially reduce restenosis in smaller vessels. Large, randomized studies are warranted to assess the impact of different DESs on outcomes in patients with small coronary arteries.

Thin strut chrome-cobalt stent implantation for treatment of de-novo lesions in small coronary vessels: results of the RISICO Italian Registry (Registro Italiano Mini VISION nei piccolo Vasi) utilizing the Mini VISION coronary stent platform

OBJECTIVES

The Registro Italiano Mini VISION nei piccoli Vasi registry is a prospective, multicenter, observational study, aimed at assessing immediate and long-term angiographic and clinical outcomes of a small-vessel cobalt-chrome super alloy-dedicated stent (Multi-Link RX VISION) in de-novo and long lesions.

BACKGROUND

Small artery size is an important determinant of poor outcomes in percutaneous coronary interventions.

METHODS

Patients with ischemic heart disease were included. The primary end point was procedural success. Secondary end points included clinical restenosis (need for target lesion revascularization ), incidence of major adverse cardiac events at 6 months, and cost-effectiveness analysis.

RESULTS

Between September 2004 and October 2005, 143 patients (mean age 67 +/- 11 years; 22% diabetes) were enrolled; 6-month follow-up was completed in May 2006. Average lesion length, mean stent length and diameter were 16.8 +/- 7.1, 17.01 +/- 3.9 and 2.41 +/- 0.14 mm, respectively. Procedural success was 96%. At 6-month follow-up, the hierarchical major adverse cardiac event rate was 11.6%, 2.9% deaths, 2.9% myocardial infarction and 5.8% target lesion revascularization. Cost-effectiveness analysis will be reported in a further publication.

CONCLUSION

Small-vessel disease treatment with Mini VISION stents permits an elevated procedural success rate with low incidence of clinical restenosis and major adverse cardiac events at mid-term follow-up. Such results require confirmation by means of a randomized controlled study against drug-eluting stents.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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).

Clinical and angiographic comparison of everolimus-eluting and paclitaxel-eluting stents in small coronary arteries: a post hoc analysis of the SPIRIT III randomized trial

BACKGROUND

Drug-eluting stents with low late loss may be particularly beneficial in small coronary arteries. We therefore examined whether the everolimus-eluting stent is superior to the paclitaxel-eluting stent in patients treated with 2.5-mm stents in the SPIRIT III trial.

METHODS

The SPIRIT III trial was a prospective, multicenter, randomized (2:1; XIENCE V: TAXUS Express) trial in which 1002 patients were enrolled. One or more 2.5-mm stents were implanted in 160 patients in the XIENCE V arm, and 59 patients, in the TAXUS arm. Mean vessel diameter was 2.36 +/- 0.30 and 2.34 +/- 0.33 mm in the XIENCE V and TAXUS groups, respectively (P = .69).

RESULTS

At 9 months, XIENCE V compared to TAXUS reduced the rates of major adverse cardiac events (cardiac death, myocardial infarction, or ischemic target lesion revascularization) from 12.5% to 3.2% (P = .02) and target vessel failure (cardiac death, reinfarction, or ischemic target vessel revascularization) from 16.1% to 5.2% (P = .02), the differences being driven primarily by reductions in target lesion revascularization (12.5% vs 1.3%; P = .002). In-stent late loss was significantly reduced by XIENCE V when compared to TAXUS (0.54 +/- 0.74 vs 0.11 +/- 0.43 mm, P = .01), as was In-segment binary angiographic restenosis (20.8% vs 4.1%, P = .02).

CONCLUSIONS

In this post hoc analysis from the SPIRIT III trial, the XIENCE V 2.5-mm stent significantly reduced clinical and angiographic restenosis compared to the TAXUS 2.5-mm stent, further supporting the hypothesis that lower late loss is beneficial in small vessel disease.

Stent‐based percutaneous coronary interventions in small coronary arteries

A third to half of all percutaneous coronary interventions involve small diameter vessels of less than 3 mm. Small vessel size is a predictor of restenosis after balloon angioplasty, as well as after stent placement. Stents deployed in small arteries, have a higher metal-to-artery ratio; this may increase the risk of sub-acute thrombosis or restenosis. Various studies have shown that stent design, stent coating, and stent strut thickness may determine event-free survival. Dedicated stents for small vessels with less amount of metal, appropriate expansion to the vessel size with correct radial force and cells morphology, and less prothrombotic properties, may further improve the results of stenting in this setting (thinner struts, fewer cells, or loops per circumference). This review provides an update on the current status, review the major trials and define the clinical utility of small vessel stenting, particularly in the era of drug-eluting stents.

Negative regulation of quinone reductase 2 by resveratrol in cultured vascular smooth muscle cells

1. Resveratrol, a polyphenol in red wine, has a cardioprotective effect. Resveratrol-targeting protein (RTP) has been purified using a resveratrol affinity column (RAC) and has been identified as quinone reductase type 2 (NQO2). We hypothesize that NQO2 is the target protein of resveratrol in vascular smooth muscle cells (VSMC) and that resveratrol inhibits proliferation of VSMC through its action on NQO2. In the present study, we investigated the correlation between NQO2 regulation and cell proliferation in VSMC in response to resveratrol treatment. 2. The RTP was purified using RAC and was detected with a NQO2 polyclonal antibody. The VSMC were incubated with resveratrol (1, 10 and 50 micromol/L) for 24, 48 and 72 h. Cell proliferation was detected by cell counting and bromodeoxyuridine (BrdU) assay. A lentiviral vector incorporating NQO2 short interference (si) RNA of short hairpin design was constructed and transduced into VSMC. Real-time quantitative polymerase chain reaction was used to measure NQO2 mRNA levels; NQO2 expression was determined by western blot analysis. 3. Using RAC, we extracted a 26 kDa protein from aortic smooth muscle, which was referred to as RTP-26. Proliferation of VSMC was inhibited by resveratrol in a concentration- and time-dependent manner. The mRNA and protein expression of NQO2 was also repressed by resveratrol in a concentration- and time-dependent manner. A similar pattern of inhibition was observed for cells treated with resveratrol (25 micromol/L) as for cells transduced with a lentiviral vector containing siRNA sequences against NQO2. 4. Collectively, these data indicate that the suppression of VSMC proliferation mediated by resveratrol correlates with NQO2 downregulation.

Impact of Vessel Size on Outcome After Implantation of Sirolimus-Eluting and Paclitaxel-Eluting Stents

OBJECTIVES

We assessed the impact of vessel size on angiographic and long-term clinical outcome after percutaneous coronary intervention (PCI) with sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) within a randomized trial (SIRTAX [Sirolimus-Eluting Stent Compared With Paclitaxel-Eluting Stent for Coronary Revascularization]).

BACKGROUND

Percutaneous coronary intervention in small-vessel disease is associated with an increased risk of major adverse cardiac events (MACE).

METHODS

A total of 1,012 patients were randomly assigned to treatment with SES (n = 503) or PES (n = 509). A stratified analysis of angiographic and clinical outcome was performed up to 2 years after PCI according to size of the treated vessel (reference vessel diameter < or =2.75 vs. >2.75 mm).

RESULTS

Of 1,012 patients, 370 patients (37%) with 495 lesions underwent stent implantation in small vessels only, 504 patients (50%) with 613 lesions in large vessels only, and 138 patients (14%) with 301 lesions in both small and large vessels (mixed). In patients with small-vessel stents, SES reduced MACE by 55% (10.4% vs. 21.4%; p = 0.004), mainly driven by a 69% reduction of target lesion revascularization (TLR) (6.0% vs. 17.7%; p = 0.001) compared with PES at 2 years. In patients with large- and mixed-vessel stents, rates of MACE (large: 10.4% vs. 13.1%; p = 0.33; mixed: 16.7% vs. 18.0%; p = 0.83) and TLR (large: 6.9% vs. 8.6%; p = 0.47; mixed: 16.7% vs. 15.4%; p = 0.86) were similar for SES and PES. There were no significant differences with respect to death and myocardial infarction between the 3 groups.

CONCLUSIONS

Compared with PES, SES more effectively reduced MACE and TLR in small-vessel disease. Differences between SES and PES appear less pronounced in patients with large- and mixed-vessel disease. (The SIRTAX trial; http://clinicaltrials.gov/ct/show/NCT00297661?order=1; NCT00297661).

Small vessel stenting with cobalt–chromium stents (Arthos Pico) in a real world setting

BACKGROUND

In current clinical practice, 35-67% of significant coronary artery lesions are located in small (<3.0 mm) vessels, a setting with poor short- and long-term results after percutaneous coronary interventions.

OBJECTIVES

The aim of the present Arthos Pico Austria Multicenter Registry is to demonstrate the safety and efficacy of the Arthos Pico (cobalt-chromium alloy) stent implantation in small coronary arteries in a real world setting.

METHODS

Two hundred and three patients (mean age, 67+/-12 years; 63% male) were included in the Registry; 199 patients (98%) were controlled clinically (including noninvasive stress tests) 6 and 12 months after stent implantation. Clinically driven angiographic controls were performed in 37 patients (18.2%) at mean 6 months after stenting. The primary endpoint of the study was the 6-month rate of major adverse cardiac events (as target vessel revascularization, all cause death, and acute myocardial infarction), the secondary endpoints were the intervention complications, and the occurrence of acute and subacute stent thrombosis.

RESULTS

The procedural success was 99%. The rates of acute and subacute stent thrombosis were 0.5 and 1.5%, respectively. During the 6-month clinical follow-up, primary endpoint events (major adverse cardiac events) were recorded in 13% of the clinically controlled patients: four patients (2%) with acute myocardial infarction; 12 patients (6%) with target vessel revascularization; and 10 patients died (5%), resulting in an event-free survival rate of 87%. Between the 6- and 12-month follow-up, additional target vessel revascularization was performed in three patients, acute myocardial infarction and death occurred in one patient each, respectively. Thus, the 12-month major adverse cardiac event-free survival rate was 85%. Patients who died had older age (76+/-7 years) and a high proportion of type C lesions (50%) at the initial angiography. Multivariate analysis revealed older age (P=0.026) and type C lesions (P=0.016) as significant predictors for all causes of death.

CONCLUSION

In conclusion, stenting of small arteries with Arthos Pico is safe and effective in the prevention of major adverse cardiac events during 6- and 12-month follow-up.

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

BACKGROUND

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).

RESULTS

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.

CONCLUSION

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

OBJECTIVES

Predictors of cardiac events and restenosis after sirolimus-eluting stent (SES) implantation in small coronary arteries were evaluated.

BACKGROUND

Although SES implantation has markedly reduced the risk of restenosis, small vessel disease remains a major cause of SES failure.

METHODS

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%).

RESULTS

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.

CONCLUSIONS

SES implantation in small coronary arteries is safe and effective, with lesion length having a major impact on restenosis and MACE.

Safety and efficacy of the 2.25-mm sirolimus-eluting Bx Velocity stent in the treatment of patients with de novo native coronary artery lesions: the SIRIUS 2.25 trial

Smaller reference vessel diameter is a recognized determinant of in-stent restenosis. The SIRIUS 2.25 trial was a prospective, nonrandomized study including 100 patients (mean age 63.4 years; 64% men, 40% with diabetes mellitus) assessing the safety and efficacy of the 2.25-mm sirolimus-eluting Bx Velocity stent in patients with de novo native coronary lesions. Using propensity score matching for gender, diabetes mellitus, left anterior descending artery target vessel, lesion length, and reference vessel diameter, the outcomes were compared with historical control groups (angioplasty and Palmaz-Schatz stent arms from the STRESS/BENESTENT I/II trials and the Bx Velocity bare metal stent arm from the RAVEL and SIRIUS trials having a reference vessel diameter <3 mm). Use of the 2.25-mm sirolimus-eluting Bx Velocity stent was associated with a high rate of procedural success (97%) and a low rate of in-hospital major adverse cardiac events (2%). The primary end point, 6-month in-lesion binary angiographic restenosis, occurred less frequently in patients treated with the 2.25-mm sirolimus-eluting Bx Velocity stent than in each of 3 historical controls (16.9% vs 30.6%, p = 0.12; 36.5%, p <0.001; 45.9%, p <0.001, respectively). This translated into lower rates of 6-month target lesion revascularization in the 2.25-mm sirolimus-eluting Bx Velocity stent group (4.0% vs 15.0% in each of 3 control groups, p = 0.01 to <0.001). By multivariate analysis, in-lesion binary restenosis was predicted by multiple implanted stents (odds ratio 10.4, p = 0.002). Four of 13 patients who developed restenosis (30.8%) had a diffuse pattern of restenosis. In the long lesion tertile (mean lesion length 19.5 mm), the in-lesion binary restenosis rate was 27.6%. In conclusion, use of the 2.25-mm sirolimus-eluting Bx Velocity stent was safe and provided favorable 6-month clinical outcomes. Use of multiple stents (in longer lesions) was an independent predictor of in-lesion restenosis.

Comparison between stenting and balloon angioplasty in patients undergoing primary angioplasty of small coronary vessels

BACKGROUND

Primary angioplasty has been shown to improve outcomes in selected patients with ST-segment elevation myocardial infarction. However, no information has been reported so far in small vessels. In the Zwolle-6 randomized trial, consecutive patients with ST-segment elevation myocardial infarction were randomized to stenting or to balloon angioplasty without any exclusion criterion. In this study, we present data on patients with small vessels (< 3.0 mm).

METHODS

From April 1997 to October 2001, 798 patients randomized to balloon angioplasty or to stenting before their initial angiogram underwent primary angioplasty of small vessels, defined according to a postprocedural reference diameter < or = 3 mm. One-year follow-up data were available from all patients.

RESULTS

Three hundred eighty-seven patients were randomized to stent, whereas 411 were to balloon. The crossover rates from balloon to stent and from stent to balloon were 28% and 13.9%, respectively (P < .001). The groups were comparable in terms of postprocedural TIMI flow, myocardial blush grade, distal embolization, and ST-segment resolution. No difference was observed in 1-year mortality (7.2% vs 5.8%, P = not significant [NS]), target vessel revascularization (17.8% vs 22.1%, P = NS), and major adverse cardiac events (24.8% vs 29.0%, P = NS) between the groups.

CONCLUSIONS

As compared with balloon angioplasty, routine stenting does not seem to improve clinical outcomes in patients undergoing primary angioplasty of small vessels. Future trials are certainly needed to evaluate the safety and benefits of drug-eluting stents in this high-risk subset of patients.

Serum lipoprotein(a) level and clinical coronary stenosis progression in patients with myocardial infarction: re-revascularization rate is high in patients with high-Lp(a)

BACKGROUND

High serum lipoprotein(a) (Lp(a)) levels are associated with coronary artery disease.

METHODS AND RESULTS

The serum Lp(a) levels of 130 patients with acute myocardial infarction (AMI) who underwent direct percutaneous coronary intervention were investigated. On the basis of Lp(a) level at 1 month after the onset of AMI, the patients were classified into 2 groups (high-Lp(a) (> or =30 mg/dl) and low-Lp(a) (< 30 mg/dl)) for evaluation of the clinical coronary stenosis progression (CCSP) rate. CCSP is defined as either target lesion revascularization (TLR) or new lesion revascularization (NLR). The CCSP rate was significantly higher in the high-Lp(a) group than in the low-Lp(a) group (65.8% vs 29.3%, p<0.01). In patients who had coronary stents in the acute phase (n=79), the CCSP and NLR rates were significantly higher in the high-Lp(a) group than in the low-Lp(a) group (45.0% vs 20.3%, p<0.05; 35.0% vs 6.8%, p<0.01), but there was no significant difference in TLR rate between the 2 groups (10.0% vs 13.6%, p=0.858).

CONCLUSIONS

High serum Lp(a) level is a significant risk factor for CCSP, but does not influence restenosis after stenting.

Sirolimus-eluting coronary stents in small vessels

BACKGROUND

This prospective multicenter study compared angiographic in-lesion late lumen loss in de novo native coronary artery lesions (vessel diameter range 2.25-2.75 mm, length range > or = 15 to < or = 30 mm) 8 months after the implantation of a sirolimus-eluting stent with that of similar vessels with the same drug-eluting stent or a bare stent of the SIRIUS study (historical controls).

METHODS AND RESULTS

One hundred one patients (study group) were matched and compared with 323 patients receiving the bare stent (bare control group) and with 350 receiving the Cypher stent (Cypher control group) in the SIRIUS trial. Mean in-lesion late loss in the study group was lower than that in the bare control group (0.20 versus 0.76 mm, P < .0001) and not inferior to that in the Cypher control group (0.27 mm, P = .3). Adverse event rates (death and myocardial infarction) were similar between groups. At 8 months, target lesion revascularization rates were 0% in the study group, 13.2% in the bare control group (P < .001), and 4.6% in the Cypher control group (P = .03).

CONCLUSIONS

The Cypher Bx Velocity stent was confirmed to be superior to the bare Bx Velocity stent in small coronary vessels in terms of in-lesion late loss 8 months after implantation.

Randomized trial of paclitaxel- and sirolimus-eluting stents in small coronary vessels

AIMS

Sirolimus- and paclitaxel-eluting stents effectively reduce restenosis in small coronary vessels. The relative efficacy of these drug-eluting stents in this high-risk subset is not known.

METHODS AND RESULTS

A total of 360 patients undergoing percutaneous coronary intervention for de novo lesions in native coronary vessels with a diameter of <2.80 mm received randomly paclitaxel-eluting stents (n=180) or sirolimus-eluting stents (n=180). The primary endpoint was in-stent late luminal loss. Secondary endpoints were angiographic restenosis and need of target lesion revascularization. The study intended to show that the paclitaxel-eluting stent is not inferior to the sirolimus-eluting stent with respect to the primary endpoint. The non-inferiority margin was set at 0.16 mm. Follow-up angiography was performed in 87% of the patients. In-stent late luminal loss in the paclitaxel-eluting stent group was 0.32 mm (upper 95% boundary, 0.42 mm), which was greater than that in the sirolimus-eluting stent group, failing to show the non-inferiority of the paclitaxel-eluting stent to the sirolimus-eluting stent (P>0.99). Angiographic restenosis was found in 19.0% of the lesions in the paclitaxel-eluting stent group and 11.4% of the lesions in the sirolimus-eluting stent group (P=0.047). Target lesion revascularization was performed in 14.7% of the lesions treated with paclitaxel-eluting stents and 6.6% of the lesions treated with sirolimus-eluting stents (P=0.008).

CONCLUSION

The paclitaxel-eluting stent is associated with a greater late luminal loss and is less effective in reducing restenosis in small coronary vessels than the sirolimus-eluting stent.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Provisional stenting for multivessel PCI

BACKGROUND

Bare stents reduce acute complications and repeat revascularization following percutaneous coronary intervention (PCI), but are costly and may lead to in-stent restenosis. It remains unclear whether stents should be universally implanted or whether provisional stenting mainly to suboptimal balloon dilatation results is an acceptable approach for multivessel PCI.

OBJECTIVE

To compare the long-term clinical restenosis and target lesion revascularization (TLR) of stented and non-stented coronary artery lesions in patients who had multivessel PCI.

METHODS

We performed retrospective analysis of matched data from 129 consecutive patients who underwent multivessel PCI (at least optimal balloon angioplasty to one coronary artery segment and balloon angioplasty plus stenting to another coronary artery in the same patient, all lesions are de novo native coronary artery lesions with vessel diameter >/=2.5 mm). The study endpoint was restenosis and repeat revascularization at one-year follow-up.

RESULTS

Baseline characteristics were similar in both groups. Low in-hospital MACE (3.1%). Acute myocardial infarction, emergency revascularization via either PCI or CABG was detected and angiographic success was achieved in 99.3% of lesions in both groups. The rate of clinically driven angiographic restenosis and TLR at one-year (follow-up 100%) was similar (17.1% versus 18.6%, P=0.871, and 13.9% versus 16.3%, P=0.728, for optimal balloon angioplasty versus provisional stenting.

CONCLUSIONS

The main findings from this study are that long-term angiographic restenosis and TLR was comparable for optimal balloon angioplasty and provisional stenting, suggesting that provisional stenting is an acceptable approach for multivessel PCI.

Latin American randomized trial of balloon angioplasty versus coronary stenting in diabetic patients with small vessel reference size (Latin American Small Vessel [LASMAL II] Trial): immediate and long-term results

Percutaneous coronary interventions (PCIs) in diabetic patients with small reference diameter vessels remain an important challenge in interventional cardiology because it is associated with increased complications and restenosis rates. Plain old balloon angioplasty (POBA) has limited efficacy in patients with lesions in small vessels. Although coronary stenting (stent) has been demonstrated to improve both immediate and long-term results after coronary intervention, small reference diameter is a strong predictor of restenosis after stent implantation. Thus, the question of how to best treat diabetic patients with lesions in small reference diameter remains unanswered. The purpose of this international and multicenter study was to compare the incidence of angiographic restenosis between percutaneous transluminal coronary angioplasty (PTCA) and stent in diabetic patients undergoing PCI of small reference diameter vessels using a specially designed phosphoryl choline (PC)-coated stent for small vessels. The patient population comprised of 220 diabetic patients with lesions in small reference diameter (< 2.9 mm but > 2.0 mm) that were randomized into two different PCI strategies: PTCA with provisional stenting (n = 109) versus stent (n = 111). In the PTCA arm, 26 patients (24%) crossed over to stent during the initial procedure; glycoproteins IIb to IIIa was used in 40.5% of patients in both groups. During initial procedure and at 30 days, both strategies of revascularitation had similar clinical success and acute complications. During long-term follow-up, even though requirements of target vessel revascularization and incidence of major adverse cardiovascular event were similar with both techniques, angiographic binary restenosis (45% with PTCA and 28% with stents, P = .047), net gain (0.74 mm with POBA and 0.94 mm with stents, P = .008), and freedom from target vessel failure (66% with POBA and 81.2% with stents, P = .013) were significantly improved when diabetic patients were initially treated with stent therapy. In summary, in diabetic patients with small coronary arteries, the use of a coronary PC coated stent as a primary device during percutaneous interventions was associated with better angiographic and long-term outcome.

Latin American randomized trial of balloon angioplasty vs coronary stenting for small vessels (LASMAL): immediate and long-term results

PURPOSE

To assess the potential role of coronary stent to improved acute success and reduce late restenosis in lesions with reference diameter <2.9 mm using a bare metal stent specifically designed for small coronary vessels. There is controversy on the results among previous studies comparing bare metal stent implantation with conventional balloon percutaneous transluminal coronary angioplasty (PTCA). Differences in baseline characteristics, inclusion and exclusion criteria, and stent design may account for these discrepancies.

METHODS

The population of this multicenter, multinational randomized study (LASMAL) consisted of 246 patients undergoing percutaneous coronary intervention of small vessel reference diameter. They were randomized into 2 strategies of percutaneous revascularization: elective primary stent (n = 124) or conventional balloon PTCA with provisional stenting (n = 122) in the presence of acute, threatened closure or flow-limiting dissections.

RESULTS

The clinical success rate was significantly better for the stent group (98.3% vs 91.8%; P = 0.038). At 30 days follow-up, requirements of target vessel revascularization (TVR) (6.6% vs 0.8%; P = 0.018) and incidence of major adverse cardiac and cerebrovascular events (MACCE) (9.8% vs 2.4%; P = 0.01) was significantly lower in the stent strategy. Postpercutaneous coronary intervention minimal luminal diameter (MLD) was significantly larger in the stent group (2.3 +/- 0.2 mm vs 2.2 +/- 0.2 mm; P = 0.003). At follow-up, MLD in the stent group was larger than with PTCA (1.7 +/- 0.7 mm vs 1.5 +/- 0.7 mm, respectively; P = 0.035). Net gain was also significantly better with stent strategy (1.1 +/- 0.7 mm vs 0.8 +/- 0.7 mm, respectively; P = 0.002). Stenting resulted in a significant lower angiographic binary restenosis (20% vs 31%; P = 0.02) than PTCA. Furthermore, patients treated with stent were more frequently free from MACCE at 9-month follow-up (death, acute myocardial infarction [AMI], stroke, repeat revascularization procedures) than those treated initially with PTCA (82.2% vs 72% of PTCA, P = 0.046).

CONCLUSIONS

The use of a specifically designed bare metal coronary phosphoril choline-coated stent as primary device during percutaneous interventions in small coronary arteries was associated with high procedural success and low in-hospital and 30-day follow-up complications. At long-term follow-up, patients initially treated with stents had lower angiographic restenosis rate and were more frequently free from major adverse cardiac events.

Late Loss in Lumen Diameter and Binary Restenosis for Drug-Eluting Stent Comparison

Background— Published rates of coronary restenosis have fallen below 10% in drug-eluting stent trials. Early evaluations of new stents have used continuous end points that are presumed surrogates for restenosis, but the generalizability and power of such end points have not been examined systematically.

Methods and Results— We examined the relationship between incremental changes in observed late loss in lumen diameter and the probability of restenosis using reported late loss from 22 published trials of various types of stents (bare-metal, drug-eluting, and small-vessel stents). Next, the power of late loss differences was compared with that of corresponding binary restenosis rates. The relationship between mean late loss and its SD was linear and did not vary with stent type (drug-eluting or bare-metal) or vessel diameter. At all levels of late loss examined (0 to 1 mm), incremental changes were associated with increasing restenosis risk (with an increasing magnitude of effect at higher levels of late loss). The power to detect a treatment effect was greater for late loss than for binary angiographic restenosis (≥32% relative increase in power, ≥24% absolute increase for late loss between 0.2 and 0.6 mm).

Conclusions— Late loss is monotonically related to restenosis risk in published stent trials. It is a generalizable and powerful angiographic end point in early or small trials of new drug-eluting stents.

Primary stenting versus primary balloon angioplasty for treating acute myocardial infarction

BACKGROUND

Balloon angioplasty following myocardial infarction (MI) reduces death, non-fatal MI and stroke compared to thrombolytic reperfusion. However up to 50% of patients experience restenosis and 3% to 5% recurrent myocardial infarction. Therefore, primary stenting may offer additional benefits compared to balloon angioplasty in patients with acute myocardial infarction.

OBJECTIVES

To examine whether primary stenting compared to primary balloon angioplasty reduces clinical outcomes in patients with acute myocardial infarction.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, Pascal, Index medicus and The Cochrane Controlled Trials Register (The Cochrane Library) from 1979 to March 2002.

SELECTION CRITERIA

Randomised controlled trials of primary stenting or balloon angioplasty prior to the invasive procedure; intervention in native coronary arteries within 24 hours after onset of symptoms of myocardial infarction; report of death or reinfarction; and follow-up of at least 1 month. Trials were excluded when randomisation occurred after an invasive procedure and if they exclusively included patients with cardiogenic shock.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected and extracted data from identified trials. Outcomes included mortality, reinfarction, coronary artery bypass grafting, target vessel revascularization, need for vascular repair or blood transfusion. Peto odds ratios were calculated. To explore the stability of the overall treatment effect various sensitivity analyses were performed.

MAIN RESULTS

We included nine trials of 4433 participants. Odds ratios for mortality after stenting compared to balloon angioplasty at 30 days, 6 and 12 months were 1.16 (95% CI 0.78 to 1.73), 1.27 (95% CI 0.89 to 1.83), and 1.06 (95% CI 0.77 to 1.45). At 30 days, 6 and 12 months odds ratios for reinfarction after stenting compared to balloon angioplasty were 0.52 (95% CI 0.31 to 0.87), 0.67 (95% CI 0.45 to 1.00), and 0.67 (95% CI 0.45-0.98) and odds ratio for target vessel revascularization after stenting compared to balloon angioplasty were 0.45 (95%CI 0.34 to 0.60), 0.42 (95% CI 0.35 to 0.51), and 0.47 (95% CI 0.38 to 0.57). The odds ratio for post-interventional bleeding complications after stenting compared to balloon angioplasty was 1.34 (95% CI 0.95 to 1.88; test of heterogeneity p > 0.1).

AUTHORS' CONCLUSIONS

There is no evidence to suggest that primary stenting reduces mortality when compared to balloon angioplasty. Stenting seems to be associated with a reduced risk of reinfarction and target vessel revascularization, but potential confounding due to unbalanced post-interventional antithrombotic/anticoagulant therapies can not be ruled out on basis of this review.

Is bare-metal stenting superior to balloon angioplasty for small vessel coronary artery disease? Evidence from a meta-analysis of randomized trials

AIMS

To compare, by meta-analytical techniques, the clinical impact of bare-metal stenting vs. balloon angioplasty for the treatment of lesions in small coronary arteries.

METHODS AND RESULTS

We included trials with random allocation and prospective comparison of angioplasty vs. stenting, reference vessel diameter<3 mm, and follow-up>or=6 months. Random effect odds ratios (OR) for death, myocardial infarction (MI), repeat revascularization (RR), and major adverse cardiac events (MACEs) were computed. In a pre-specified subgroup analysis, we compared stenting with optimal (post-procedural stenosis<20%) and suboptimal (>20%) angioplasty. Thirteen studies (4383 patients) were selected. No differences were found in terms of death and MI, while MACEs, mainly driven by RR, were significantly less common after stenting (17.6%) than after angioplasty (22.7%), OR 0.71 (0.57-0.90). Heterogeneity among trials was present. When considering only optimal angioplasty, MACE rates were homogeneously similar, 17.9 vs. 21.1%, OR 0.86 (0.66-1.11). If angioplasty were suboptimal, MACEs were significantly more common after angioplasty (24%) than after stenting (17.3%), OR 0.62 (0.44-0.88).

CONCLUSION

Stenting is superior to balloon angioplasty for the treatment of small vessels, in particular after suboptimal angioplasty. However, MACE and RR rates remain high after stenting, and the advantage of stent over angioplasty is moderate. An optimal balloon angioplasty strategy (with provisional stenting) may achieve results not inferior to routine stenting.

Angioplasty and stents in coronary artery disease: a systematic review and meta-analysis

OBJECTIVES

To undertake a systematic review of the clinical effectiveness of routine percutaneous transluminal coronary angioplasty (PTCA) plus stenting vs PTCA alone.

DATA SOURCES

MEDLINE; EMBASE; Science Citation Index; The Cochrane Library; cardiovascular journals and conference proceedings; Internet resources (including industry supported web pages); and reference lists of included studies and relevant reviews.

REVIEW METHODS

Study selection included published and unpublished randomized controlled trials (RCTs) comparing the use of coronary stents to PTCA. Outcome measures assessed included death, acute myocardial infarction (AMI), event rate (such as major cardiac adverse events (MACE) or other composite measures), and binary restenosis (BR). Data extraction and quality assessment were conducted according to internationally recognized methods. Data synthesis included meta-analysis of assessed outcomes, reported as odds ratios (ORs).

RESULTS

Fifty RCTs involving 16,500 patients met the inclusion criteria (39 full articles, 11 abstracts). Of these, 23 studies compared stenting with PTCA in patients with non-specific coronary artery disease (CAD), 11 compared stents with PTCA following AMI, 8 included patients with small coronary arteries and 8 included patients whose vessels had chronic total occlusion. There were no differences in rates of death or AMI. There were reductions in the rates of MACE (death, AMI or revascularization) with stents compared to PTCA (at 6 months, for non-specific group OR: 1.64, 95% CI 1.44-1.87; for AMI group OR: 2.36, 95% CI 1.92-2.89; for small vessel group OR: 1.38, 95% CI 1.10-1.74; at 12 months, for non-specific group OR: 1.31, 95% CI 1.11-1.55; for AMI OR: 2.26, 95% CI 1.47-3.46). Reporting of combined major adverse cardiac events was inconsistent across studies. Most events were revascularizations that may have been partly driven by protocol-required angiograms. Stents reduced BR rates at angiogram at 6 months compared to PTCA in all groups.

CONCLUSION

We found no differences in mortality or AMI, but the studies were not powered to identify changes in these endpoints. Coronary stenting is associated with reduced restenosis and combined adverse cardiac events, primarily revascularizations. However, the frequency of revascularization may have been distorted by protocol-dictated angiography.

Stent implantation in very small coronary arteries: the Tsunami SV International Registry

The aim of this multicenter registry was to examine the in-hospital and long-term clinical outcomes of patients who underwent Tsunami SV stent implantation for the treatment of lesions involving coronary arteries with a reference diameter of <2.5 mm. The angiographic success rate was 97.5%. No in-hospital or 30-day major adverse cardiac events occurred. During the 6-month follow-up, there was 1 cardiac death (1%), and 5 subjects (4.8%) underwent repeat target lesion revascularization.

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.

A randomized trial comparing phosphorylcholine-coated stenting with balloon angioplasty as well as abciximab with placebo for restenosis reduction in small coronary arteries

OBJECTIVE

The objective of this randomized trial was to assess the antirestenotic effects of phosphorylcholine (PC)-coated stents as well as of abciximab in small coronary arteries when compared with percutaneous transluminal coronary angioplasty (PTCA) and placebo respectively.

BACKGROUND

Stent coating with PC has been shown to reduce protein absorption and platelet activation which may reduce the risk of restenosis. Furthermore, on the basis of nondedicated studies abciximab is believed to reduce the risk of restenosis after coronary interventions.

METHODS

A total of 502 patients with lesions situated in small coronary arteries (vessel diameter </=2.5 mm) were randomly assigned to be treated with either PC-coated stents (n = 253) or PTCA (n = 249) and with either abciximab (n = 251) or placebo (n = 251) with the use of a 2 x 2 factorial design. All patients were pretreated with 600 mg clopidogrel. The primary end-point was the incidence of angiographic restenosis (>/=50% diameter stenosis) at follow-up; death or myocardial infarction, and target vessel revascularization (TVR), were assessed as secondary end-points.

RESULTS

Angiographic restenosis did not differ between patients treated with PC-coated stents or with PTCA (39.0% vs. 34.2%; P = 0.30) and between patients receiving abciximab or placebo (39.3% vs. 34.3%; P = 0.29). Similarly, the need for TVR at 1-year follow-up did not differ between patients receiving PC-coated stents or PTCA (20.2% vs. 20.5%; P = 0.98) as well as between patients treated with abciximab or placebo (18.7% vs. 21.9%; P = 0.44).

CONCLUSIONS

PC-coated stents and abciximab failed to reduce the incidence of angiographic restenosis after percutaneous coronary intervention of small coronary arteries. These data strengthen the belief that future studies on prevention of restenosis in small coronary arteries should focus on drug-eluting stents.

Coronary stenting versus balloon angioplasty in small vessels

OBJECTIVES

A meta-analysis of 11 randomized trials was done to compare stenting versus balloon angioplasty (BA) in small coronary vessels.

BACKGROUND

Randomized studies on coronary stenting (CS) in small vessels have yielded controversial results.

METHODS

Eleven randomized trials on CS versus BA in small vessels, including angiographic re-evaluation at six months, were analyzed.

RESULTS

The BeStent (Medtronic Instent, Minneapolis, Minnesota) was used in four studies, the Multi-Link (Guidant, Advanced Cardiovascular Systems Inc., Santa Clara, California) in three trials, and the NIR (Boston Scientific Corp., Boston, Massachusetts), JoStent (Jomed International AB, Helsingborg, Sweden), Tenax (Biotronik, Berlin, Germany), and BioDivysio (Abbott Vascular Devices, Redwood City, California) in the remaining four trials. Overall, 3,541 patients were included (1,672 allocated to BA and 1,869 to stent). The rate of cross-over from balloon to stent in the pooled population was 19%, and unsuccessful stent deployment occurred in 2% of the patients allocated to stent. The pooled rates of restenosis were 25.8% and 34.2% in patients allocated to stent and balloon, respectively (p = 0.003) (risk ratio [RR] 0.77; 95% confidence interval [CI] 0.65 to 0.92). A smaller reference vessel diameter at baseline was associated with a higher risk reduction in the restenosis rate (y = -3.551 + 1.826 [x]; p = 0.012). Patients allocated to stent had lower rates of major adverse cardiac events (15.0% vs. 21.8%, p = 0.002; RR 0.70; 95% CI 0.57 to 0.87) and new target vessel revascularizations (12.5% vs. 17.0%, p = 0.004; RR 0.75, 95% CI 0.61 to 0.91).

CONCLUSIONS

Elective stenting is superior to provisional stenting in small coronary arteries. This benefit is more evident in smaller coronary arteries.

Randomized comparison of balloon angioplasty versus silicon carbon-coated stent implantation for de novo lesions in small coronary arteries

The objectives of this study were to compare the short- and long-term clinical and angiographic outcomes of conventional balloon angioplasty versus elective silicon carbide-coated stent implantation in de novo lesions in small coronary arteries (<3.0 mm). Angioplasty of small coronary arteries is associated with high restenosis rates. The beneficial effects of stent implantation on restenosis rates and clinical outcomes have been suggested by observational studies. However, randomized trials comparing balloon angioplasty with stenting show conflicting results. A total of 496 patients with a de novo stenosis in a coronary artery, with a diameter between 2.0 and 3.0 mm, were randomly assigned to balloon angioplasty (n = 246) or stent implantation (n = 250). One-year clinical and 6-month angiographic follow-up were performed. Baseline characteristics were similar for the 2 groups, with 16% having diabetes and 77% complex lesions (type B or C). Crossover to stents occurred in 29% of patients randomized to balloon angioplasty. At 6 months, angiographic restenosis rates were 25% versus 21% for the angioplasty and stent groups, respectively (p = NS). One-year clinical follow-up showed no difference in occurrence of major adverse cardiac events. Elective silicon carbon-coated stent implantation in small coronary arteries is safe and effective, with no beneficial effect on angiographic or clinical outcome compared with balloon angioplasty with provisional stenting.

Impact of coronary artery stents on mortality and nonfatal myocardial infarction: meta-analysis of randomized trials comparing a strategy of routine stenting with that of balloon angioplasty

BACKGROUND

A strategy of routine stenting has been shown to reduce the need for target-vessel revascularization compared with a strategy of balloon angioplasty alone; however, the impact on mortality and frequency of nonfatal myocardial infarction is unclear. The aim of this study was to provide a quantitative comparison of the impact of coronary stenting on the rates of mortality and myocardial infarction with that of balloon angioplasty with provisional stenting.

METHODS

We performed a meta-analysis of randomized trials comparing routine coronary stenting to percutaneous transluminal coronary angioplasty (PTCA), including only those trials that used combination antiplatelet therapy (aspirin and a thienopyridine) as an adjuvant to stenting. Such trials included: the Belegian Netherlands Stent Study (BENESTENT) II, Optimal Coronary Balloon Angioplasty With Provisional Stenting Versus Primary Stent (OCBAS), Balloon Optimization vs Stent Study (BOSS), Evaluation of Platelet IIb/IIIa Inhibitor for Stenting (EPISTENT), Optimum Percutaneous Transluminal Coronary Angioplasty Compared With Routine Stent Strategy (OPUS-1), French Optimal Stenting Trial (FROST), Angioplasty or Stent (AS), and Doppler Endpoint Stenting International Investigation (DESTINI) trials for de novo coronary artery lesions; the Stent vs Percutaneous Angioplasty in Chronic Total Occlusion (SPACTO), Total Occlusion Study of Canada (TOSCA), Stent or Angioplasty after Recanalization of Chronic Coronary Occlusions (SARECCO), and Mayo-Japan Investigation for Chronic Total Occlusion (MAJIC) trials for coronary occlusions; the Primary Angioplasty Versus Stent Implantation in Acute Myocardial Infarction (PASTA), Gianturco-Roubin in Acute Myocardial Infarction (GRAMI), Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO), Immediate Coronary Angioplasty with Elective Wiktor Stent Implantation Compared with Conventional Balloon Angioplasty in Acute Myocardial Infarction (STENTUIM-2), Stent Primary Angioplasty in MI (Stent-PAMI), Zwolle, and Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trials for acute ST-segment elevation myocardial infarction; and the Intracoronary Stenting or Angioplasty for Restenosis Reduction in Small Arteries (ISAR-SMART), Park, Stenting in Small Arteries (SISA), and Bestent in Small Arteries (BESMART) trials for small vessels.

RESULTS

The 23 trials enrolled 10,347 patients, with 5130 patients randomized to receive stent and 5217 patients randomized to receive balloon angioplasty. A total of 902 (17 %) of patients crossed over from a strategy of balloon angioplasty to stent placement because of the inability to achieve a satisfactory result with a balloon. No significant difference was observed between the stent group and PTCA group in the rates of death or myocardial infarction, despite a significant reduction in the frequency of major adverse cardiac events (odds ratio, 0.59; 95% CI, 0.50-0.70; P <.001), which was driven entirely by a reduction in target vessel revascularization.

CONCLUSIONS

An initial strategy of stent placement versus balloon angioplasty with provisional stenting is associated with a similar mortality rate and frequency of nonfatal myocardial infarction after a mean follow-up period of 12.8 months. Patients who underwent stent placement had a significantly lower risk of major adverse cardiac events only when target revascularization is included as an end point.

Treatment of very small vessels with 2.25-mm diameter sirolimus-eluting stents (from the RESEARCH registry)

A total of 91 patients with 112 lesions received 2.25-mm sirolimus-eluting stents (SESs), and these lesions were compared with those treated with SESs of > or =2.5-mm diameter in the same procedure (n = 109). The reference diameters were 1.88 +/- 0.34 and 2.52 +/- 0.57 mm, respectively (p <0.01). At follow-up, the late lumen loss was 0.07 +/- 0.48 mm for the 2.25-mm SES versus 0.03 +/- 0.38 mm for the larger SES (p = 0.5), and the binary restenosis rate was 10.7% versus 3.9%, respectively (p = 0.1). The 12-month target lesion revascularization rate was 5.5%. In conclusion, 2.25-mm SESs were associated with low rates of clinical and angiographic late complications.

Effect of stents in reducing restenosis in small coronary arteries: A meta-analysis

The ability of stents to reduce restenosis was established in larger coronary arteries. Clinical trials of stenting in smaller vessels have yielded conflicting results due in part to their sample sizes. The aim of this meta-analysis was to increase the statistical power by pooling data from these clinical trials. Trials were identified from Medline search, review of recent cardiology meetings' abstracts, and manual review of bibliographies. Studies were included if they were prospective randomized controlled trials. Endpoints examined included a dichotomized definition of angiographic restenosis, target lesion revascularization (TLR), target vessel revascularization (TVR), or any repeat revascularization. Pooling of data was performed by calculating a Mantel-Haenszel odds ratio (OR). The analysis included 2,598 patients enrolled in eight clinical trials. Stenting significantly reduced restenosis (OR = 0.62; 95% CI = 0.61-0.63). Concordantly, stenting reduced TLR (OR = 0.49), TVR (OR = 0.90), and any revascularization (OR = 0.48). This meta-analysis supports the hypothesis that stenting reduces restenosis in small coronary arteries as well as in larger coronary arteries. The apparent discordant result of individual clinical trials was due in part to underpowering related to small sample sizes.

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.

Balloon angioplasty plus cilostazol administration versus primary stenting of small coronary artery disease: Final results of COMPASS

Efficacy of primary stenting in small coronary artery disease is still controversial. Cilostazol has been reported to control restenosis after balloon angioplasty (BA). The aim was to compare primary stenting with BA plus cilostazol administration in small coronary artery disease. Of 106 lesions located in small coronary artery (reference < 3.0 mm), 50 lesions were randomly assigned to the stenting and 56 lesions to the BA-cilostazol group. Multilink stent was implanted in the stenting group. In the BA-cilostazol group, cilostazol (200 mg/day) without aspirin was administered for 6 months after BA. Ticlopidine was given for 1 month when bailout stent was implanted. Serial quantitative angiography was performed at the procedure and 6 months. The primary endpoint was 6-month angiographic restenosis. Clinical event rates at 1 year were also assessed. Baseline characteristics were similar. All procedures were successful. Bailout stenting was performed in three lesions in the BA-cilostazol group. No side effects of cilostazol were observed. Postprocedural lumen diameter was significantly larger (2.69 vs. 2.03 mm; P < 0.0001) in the stenting group. However, the follow-up lumen diameter was not different (1.76 vs. 1.85 mm, stenting vs. BA-cilostazol). Although the difference was not statistically significant, restenosis rate was lower in the BA-cilostazol group (13.2% vs. 24.5%; P = 0.11). Subacute thrombosis occurred in one patient and target revascularization rate was higher in the stenting group (22.0% vs. 10.7%; P = 0.10). BA plus cilostazol administration seems to be a favorable strategy for small coronary artery disease.