Midterm outcomes of bare-metal stenting after primary stenting for ST-segment elevated myocardial infarctions in the drug-eluting stent era: a propensity score-matched comparison with sirolimus-eluting stent

We performed a propensity score-matching comparison of the midterm clinical and angiographic outcomes after primary stenting between using bare-metal stents (BMSs) and sirolimus-eluting stent (SES; Cypher Bx Velocity) for ST-segment elevated myocardial infarction (STEMI), because, in the drug-eluting stent era, the indication of the BMSs when a large balloon diameter is required remained to be controversial. This was a single-center, nonrandomized, retrospective study investigated in October 2013 by enrolling STEMI patients treated with primary stenting using either SES (n = 468) or BMS (n = 171) between September 2004 and December 2011. In 204 patients, the baseline-adjusted values produced similar mean maximum balloon sizes (BMS 3.67 ± 0.47 mm; SES 3.70 ± 0.56 mm; p = 0.477), and the incidence rates of binary in-stent restenosis (% diameter stenosis >50 % on secondary angiography) after SES placement (7.8 %) was significantly lower than that after BMS placement (23.5 %; p = 0.002). In baseline-adjusted 300 patients, the incidence of the clinical endpoints comprising cardiac death, nonfatal recurrent MI, and definite stent thrombosis after SES placement (11.3 %; 1241 ± 786 days; p = 0.557) was not significantly different from after BMS placement (8.7 %; mean follow-up period, 549 ± 486 days; p = 0.557). SES was not significantly related to the clinical endpoint [hazard ratio 2.31; 95 % confidence interval (CI) 0.88-6.08; p = 0.089). BMS did not offset the SES's angiographic efficacy for primary stenting for STEMI patients, despite placed using a large-sized balloon.

Repeated occurrence of slow flow phenomenon during and late after sirolimus-eluting stent implantation

A 78-year-old man with unstable angina showed 90% stenosis in the proximal left anterior descending artery. Pre-procedural intravascular ultrasound revealed ruptured plaque and attenuated plaque in the lesion. Under these conditions, two overlapping sirolimus-eluting stent (SES) implantation in this lesion resulted in slow flow which was recovered by intracoronary nitrates, nicorandil, and nitroprusside without further complications. When the patient showed up again 5 years later with recurrence of angina pectoris, angiography revealed a hazy ulcerated in-stent restenosis (ISR) at the site of the SES. Pre-procedural optical coherence tomography (OCT) imaging revealed multiple intimal ruptures, cavity formation behind the stent struts, a thin-cap fibroatheroma containing neointima surrounded by signal-poor, lipid-rich area in the proximal SES, suggesting the progression of neoatherosclerosis within SES. Importantly, there occurred slow flow again after balloon angioplasty for this lesion. We would suggest careful OCT examination is warranted to confirm development of neoatherosclerosis within the stent, and distal protection device should be considered to prevent slow flow phenomenon even in a patient with very late ISR.

Pathological perspective of drug-eluting stent thrombosis

Although very late stent thrombosis (VLST) after drug-eluting stent (DES) implantation remains a major concern, the precise mechanisms have not been clarified. An association between late acquired incomplete stent apposition (ISA) and VLST of DES has been suggested by several intravascular ultrasound studies demonstrating very high prevalence of ISA in the setting of VLST. To clarify the pathological mechanisms of VLST, we investigated vascular responses of coronary arteries of VLST cases after DES implantation.

Comparison of everolimus- and paclitaxel-eluting stents in patients with acute and stable coronary syndromes: pooled results from the SPIRIT (A Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System) and COMPARE (A Trial of Everolimus-Eluting Stents and Paclitaxel-Eluting Stents for Coronary Revascularization in Daily Practice) Trials

OBJECTIVES

This study sought to compare the clinical outcomes of everolimus-eluting stents (EES) versus paclitaxel-eluting stents (PES) in patients with acute coronary syndromes (ACS) and stable coronary artery disease (CAD).

BACKGROUND

Although randomized trials have shown superiority of EES to PES, the safety and efficacy of EES in ACS is unknown.

METHODS

We performed a patient-level pooled analysis from the prospective, randomized SPIRIT (Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System) II, III, IV, and COMPARE (A Trial of Everolimus-Eluting Stents and Paclitaxel-Eluting Stents for Coronary Revascularization in Daily Practice) trials in which 2,381 patients with ACS and 4,404 patients with stable CAD were randomized to EES or to PES. Kaplan-Meier estimates of death, myocardial infarction (MI), ischemia-driven target lesion revascularization, and stent thrombosis were assessed at 2 years and stratified by clinical presentation (ACS vs. stable CAD).

RESULTS

At 2 years, patients with ACS compared with stable CAD had higher rates of death (3.2% vs. 2.4%, hazard ratio [HR]: 1.37 [95% confidence interval (CI): 1.02 to 1.85], p = 0.04) and MI (4.9% vs. 3.4%, HR: 1.45 [95% CI: 1.14 to 1.85], p = 0.02). In patients with ACS, EES versus PES reduced the rate of death or MI (6.6% vs. 9.3%, HR: 0.70 [95% CI: 0.52 to 0.94], p = 0.02), stent thrombosis (0.7% vs. 2.9%, HR: 0.25 [95% CI: 0.12 to 0.52], p = 0.0002), and ischemia-driven target lesion revascularization (4.7% vs. 6.2%, HR: 0.69 [95% CI: 0.48 to 0.99], p = 0.04). In patients with stable CAD, EES reduced the rate of death or MI (4.5% vs. 7.1%, HR: 0.62 [95% CI: 0.48 to 0.80], p = 0.0002), stent thrombosis (0.7% vs. 1.8%, HR: 0.34 [95% CI: 0.19 to 0.62], p = 0.0002), and ischemia-driven target lesion revascularization (3.9% vs. 6.9%, HR: 0.55 [95% CI: 0.42 to 0.73], p < 0.0001).

CONCLUSIONS

Treatment with EES versus PES provides enhanced safety and efficacy regardless of the acuity of the clinical syndrome being treated and appears to mitigate the increased risk of stent thrombosis associated with ACS. (A Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System in the Treatment of Patients With de Novo Native Coronary Artery Lesions [SPIRIT II]; NCT00180310; SPIRIT III: A Clinical Evaluation of the Investigational Device XIENCE V Everolimus Eluting Coronary Stent System [EECSS] in the Treatment of Subjects With de Novo Native Coronary Artery Lesions [SPIRIT III]; NCT00180479; SPIRIT IV Clinical Trial: Clinical Evaluation of the XIENCE V Everolimus Eluting Coronary Stent System in the Treatment of Subjects With de Novo Native Coronary Artery Lesions [SPIRIT IV]; NCT00307047; A Trial of Everolimus-Eluting Stents and Paclitaxel-Eluting Stents for Coronary Revascularization in Daily Practice: the COMPARE Trial [COMPARE]; NCT01016041).

Three-year follow-up of sirolimus-eluting stents vs. bare metal stents for acute myocardial infarction

BACKGROUND

The long-term safety and efficacy of drug-eluting stents for patients with acute myocardial infarction (AMI) remain controversial.

METHODS AND RESULTS

A total of 143 consecutive patients who presented between August 2004 and July 2006 with AMI and who underwent primary percutaneous coronary intervention (PCI) using sirolimus-eluting stents (SES), were compared with a historical control cohort of 129 consecutive patients who presented between August 2002 and July 2004 and who underwent primary PCI using bare metal stents (BMS). The rate of major adverse cardiovascular events at 3 years was significantly lower in the SES group than in the BMS group (20.3% vs. 33.1%, respectively; P=0.01). This reduction was mainly driven by a decrease in the rate of target vessel revascularization (12.3% vs. 22.4%, respectively; P=0.02). There was no significant difference in the rate of cardiovascular death (4.5% vs. 5.7%, respectively; P=0.67), non-fatal myocardial infarction (4.5% vs. 9.2%, respectively; P=0.16), coronary artery bypass grafting (2.3% vs. 2.5%, respectively; P=0.93), stroke (2.4% vs. 0.8%, respectively; P=0.35), and stent thrombosis (2.9% vs. 2.3%, respectively; P=0.80) between the 2 groups.

CONCLUSIONS

SES can be used safely and effectively in patients with AMI.