Intravascular ultrasound guidance in drug-eluting stent deployment

The role of routine intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) in the bare metal stent era remains controversial. The potential to reduce revascularization was reported without impacting non-fatal myocardial infarction and death. Drug-eluting stents (DES) have realized improved clinical results in patients undergoing PCI but are not free of restenosis and are limited by thrombosis, particularly in more complex lesion types. Stent under-expansion, malposition, and incomplete lesion coverage have been identified as the key mechanisms of DES failure. The identification of these features on IVUS and their subsequent treatment may lead to improved clinical outcomes. Though a clinical benefit is intuitive, results from randomized trials are still needed to justify routine IVUS guided DES implantation. The Authors provide a review of the currently available evidence pertaining to the potential clinical benefit of IVUS guidance in DES implantation.11 page(s

Percutaneous treatment of a giant coronary aneurysm using a Symbiot stent

Percutaneous treatment of coronary aneurysms has been proven to be a safe and effective alternative to surgery. We report the successful treatment of a giant proximal left circumflex artery aneurysm with distal occlusion in a 76-year-old man using the new generation of covered stent, Symbiot, a polytetrafluoroethylene-covered self-expandable stent (Boston Scientific, Natick, MA).2 page(s

The clinical outcome of restricting drug-eluting stents to patients at highest risk of restenosis

AIMS: To assess the clinical outcomes of patients where drug eluting stents (DES) were restricted to those at highest risks of restenosis, we compared three different strategies for stent implantation: bare metal stents (BMS) only, DES only and a group where DES use was restricted (RES). METHOD AND RESULTS: Initial comparison was made between BMS only (279 patients, 316 lesions) and DES only (272 patients, 302 lesions). The endpoints of death, non-fatal myocardial infarction and target lesion revascularisation (TLR) [MACE] were assessed at 12 months. The incidence of MACE in the BMS only and DES only groups were 14% and 7% (p=0.002) and TLR was 8% and 1% (p<0.0001). Comparison was then made between these results and a third group where DES was restricted to patients at highest risk of restenosis. The restricted group (RES) comprised 249 patients (271 lesions) of which 53% received DES. RES remained significantly better than BMS, MACE (14% vs. 8%, p=0.02) and TLR (8% vs. 3%, p=0.02). When RES was compared with DES only, there was no significant difference in MACE (8% vs. 7% p=0.42), but there was a significantly lower TLR rate in the DES only group (1% vs. 3% p=0.04). CONCLUSIONS: The overall incidence of events in patients where DES use was restricted to 53% of patients remains low and this may be an acceptable treatment strategy to reduce costs.6 page(s

Angiographic and procedural correlates of stent thrombosis after intracoronary implantation of drug-eluting stents

BACKGROUND: Stent thrombosis (ST) following the implantation of drug-eluting stents (DES) remains the major limitation of this new technology. The identification of modifiable correlates of ST may help reduce this catastrophic event. METHODS: This was a retrospective, single-center, lesion-based study. A cohort of 45 consecutive lesions (35 patients) initially treated with successful DES implantation from May 2003 to February 2005 that re-presented with ST within 12 months was identified. This cohort was compared to a control group of 1,620 unselected lesions (1,187 patients) that were successfully treated with DES implantation and which remained free of ST. Comparison of angiographic and procedural features was made between the ST and no-ST groups, and logistic regression analysis was then performed to identify independent correlates of ST. For the purposes of the study only definite ST events (angiographically or autopsy proven) were considered. RESULTS: Independent angiographic predictors of cumulative ST at 12 months were left anterior descending (LAD) artery (OR: 1.91, CI: 1.01-3.59, P = 0.045), bifurcation (OR: 2.43, CI: 1.06-5.56, P = 0.035), and in-stent restenotic (OR: 2.64, CI: 1.12-6.25, P = 0.027) lesions. Procedural predictors were number of stents per lesion (OR: 2.30, CI: 1.29-4.11, P = 0.005) and intravascular ultrasound (IVUS) guidance (OR: 0.45, CI: 0.24-0.84, P = 0.013). Correlates of subacute events were LAD artery, proximal segment, and lack of IVUS guidance. Correlates of late ST were bifurcation and in-stent restenotic lesions. CONCLUSIONS: Angiographic and procedural correlates of subacute and late ST after DES implantation differ. Lack of IVUS guidance was the only modifiable predictor identified. Treatment of bifurcation and restenotic lesions was predictive of late events.7 page(s

Can direct stenting in selected saphenous vein graft lesions be considered an alternative to percutaneous intervention with a distal protection device?

BACKGROUND: Distal embolization during percutaneous coronary intervention (PCI) of saphenous vein graft (SVG) lesions is associated with a high rate of myonecrosis. Although direct stenting (DS) is feasible with less catheter manipulations, its ability to prevent distal embolization in SVG lesions compared with distal protection devices (DPD) is unknown. METHODS: The study included 188 SVG lesions subjected to PCI, 101 patients with 101 lesions treated with DPD, and 87 patients with 87 lesions by DS without DPD. Major adverse cardiovascular events (MACE) in-hospital and at 30 days were compared. RESULTS: Baseline characteristics were comparable, except for higher frequencies of unstable angina (53% vs. 67%, P = 0.045) and prior myocardial infarction (38% vs. 53%, P = 0.07) in the DS group. There was no difference in lesion type aside from more restenotic lesions in the DS group (7% vs. 16%, P = 0.047). Drug-eluting stent deployment was similar. Stent length in the DPD group (22.8 +/- 7.2 mm) was significantly longer than that in the DS group (17.6 +/- 8.0 mm, P 2 times the upper limit of normal did not differ (11% vs. 6%, P = 0.2). There were no differences in MACE rates in-hospital and at 30 days. By multivariate analysis, neither DPD nor DS was a significant predictor for maximum CK-MB value. CONCLUSION: DS should be considered an alternative treatment to PCI with DPD for selected SVG lesions.5 page(s

Outcomes after sirolimus- and paclitaxel-eluting stent implantation in patients with insulin-treated diabetes mellitus

Insulin-treated diabetic patients undergoing drug-eluting stent implantation are prone to high rates of adverse cardiac events. The efficacy of the sirolimus- (SES) and paclitaxel-eluting stent (PES) in this population was analyzed. Registry data for 434 consecutive patients with insulin-treated diabetes who underwent SES or PES implantation were analyzed. The end point, major adverse cardiac events (MACEs) at 1 year, was high for patients with SESs and PESs (20.6% vs 20.2%; p=0.91). Cox regression and propensity analysis were used to compare outcomes. The adjusted hazard ratio (HR) for MACEs according to stent type (Cox model) was 1.0 (95% confidence interval [CI] 0.64 to 1.76, p=0.82). The propensity score-adjusted (C statistic=0.66) HR was 0.95 (95% CI 0.56 to 1.61, p=0.84). Stent thrombosis rates were relatively high at 2.0% for SESs and 1.5% for PESs (p=0.49). The propensity score-adjusted HR for stent thrombosis was 2.7 (95% CI 0.31 to 23.6, p=0.37). In conclusion, SESs and PESs are similarly efficacious in insulin-treated diabetic patients. The high MACE and stent thrombosis rates are of concern. Additional studies in this group of patients are required to determine the optimal mode of revascularization and minimize the overall stent thrombosis rate.6 page(s

Correlates of clinical restenosis following intracoronary implantation of drug-eluting stents

Despite significant decreases in restenosis and repeated intervention achieved using drug-eluting stents (DESs), the benefit has not been homogenous across all patient and lesion subsets. Identification of correlates of DES restenosis may allow a differing management approach and lead to improved patient outcomes. The study population consisted of 3,535 consecutive patients (5,046 lesions) who underwent successful sirolimus- or paclitaxel-eluting stent implantation for >or=1 native coronary artery or bypass graft lesion from April 2003 to September 2006. From this cohort, 197 patients (237 lesions) were identified to have in-stent restenosis (ISR) requiring revascularization within 12 months of stent implantation. This group was compared with the remainder of the patient population. Logistic regression analysis was performed to identify independent predictors of DES ISR. Independent correlates of DES ISR using multivariate analysis included both clinical and procedural factors. Clinical predictors were age, hypertension, and unstable angina. Procedural predictors were left anterior descending artery intervention, number of stents implanted, stented length/lesion, and lack of intravascular ultrasound guidance. Implantation of >or=3 stents was associated with a significantly higher restenosis risk (9.7% vs 5.1%; p=0.0003). A 10-mm increase in stented length was associated with an adjusted odds ratio of 1.18 (95% confidence interval 1.03 to 1.35). Diabetes, stent diameter, and stent type were found not to be predictive of DES ISR. In conclusion, correlates of DES ISR included both clinical and procedural factors. Limiting the number of stents and stented length, in addition to intravascular ultrasound guidance, may minimize DES ISR.5 page(s