Drug-eluting Stent Insertion Research Articles

Clinical Effects of Additional Cilostazol Administration After Drug-Eluting Stent Insertion

Background and Objectives: Cilostazol, a selective inhibitor of phosphodiesterase III (PDE III), prevents inactivation of the intracellular second messenger cyclic adenosine monophosphate (cAMP) and irreversibly inhibits platelet aggregation and vasodilation. Hence, we performed this prospective randomized study to evaluate the clinical effects of additional cilostazol administration in patients receiving dual antiplatelet therapy after drugeluting stent (DES) insertion. Subjects and Methods: Between December 2003 and June 2006, we enrolled a total 603 consecutive patients who underwent successful percutaneous coronary intervention (PCI) with DES insertion at Dong-A University Hospital. Study patients received dual antiplatelet therapy (aspirin and clopidogrel, n=301) for at least six months or dual antiplatelet therapy (six months) combined with cilostazol medication for one month (triple therapy, n=302) after PCI. We investigated the incidence of major adverse cardiac events (MACE) at one month and six months after the initiation of medical therapy. MACE was defined as a composite of death, myocardial infarction (MI), stent thrombosis, and target lesion revascularization (TLR). Platelet function was evaluated in 66 patients (dual therapy group, n=40; triple therapy group, n=26) using a Chrono-Log platelet aggregometer and the VerifyNow P2Y12 assay system. Results: The MACE rate was 0.66% in the triple therapy group (death only, 0.67%) and 1.67% in the dual therapy group (death, 0.67%; MI, 0.67%; stent thrombosis, 0.99%; TLR, 0.99%) at one month after PCI (p=0.087). At six months, there were no differences in the MACE rate between the two groups (triple group vs. dual group=2.65% vs. 3.99%, p=0.864). In laboratory tests, platelet aggregation induced by agonists of ADP (27.92±13.04% vs. 40.9±15.78%, p=0.0008), collagen (13.73±6.95% vs. 27.43±14.87%, p=0.03), and epinephrine (10.38±7.82% vs. 15.5±10.45%, p=0.0000) were lower in the triple therapy group versus the dual therapy group. However, platelet aggregation induced by agonists of arachidonic acid (3.23±1.07% vs. 3.78±2.12%, p=0.23) and ristocetin (29.19±35.55% vs. 44.78±32.65%, p= 0.07) and aspirin reaction unit (412.96±96.25 vs. 427.93±76.24, p=0.48) measured by VerifyNow were not different in the triple group versus the dual group. Conclusion: Additional administration of cilostazol did not decrease the MACE rate when compared to dual therapy six months after PCI in patients with DES. (Korean Circ J 2009;39:21-25)

Drug-eluting Stent Insertion in the Treatment of In-stent Renal Artery Restenosis in Three Renal Transplant Recipients

Percutaneous transluminal angioplasty (PTA) with or without stent insertion is the treatment of choice in transplant renal artery stenosis. However, in-stent restenosis occurs in as many as 13% of patients after PTA and stent insertion. This article describes three patients with recurrent transplant renal artery in-stent stenosis who were treated with paclitaxel-eluting stents. In two patients, the transplant renal artery remained patent after insertion of the drug-eluting stent (DES), and one patient required balloon angioplasty 7 months after the DES was inserted.

Perioperative Complications in Patients with Drug-Eluting Stents: A Three-Year Audit at Geelong Hospital

Drug-eluting stents are a recommended treatment for lesions in the coronary arteries. Stent insertion requires the patient remain on anti-platelet medication for a minimum of six months after insertion. A serious consequence of ceasing anti-platelet medication is late stent thrombosis leading to myocardial infarction in the territory of the drug-eluting stent. Continuing anti-platelet medication can lead to excessive bleeding at the time of surgery. Understanding the risk of complications attributable to bleeding or myocardial ischaemia will help in defining the optimal management of these patients at the time of non-cardiac surgery. This study is a retrospective database analysis and case note review of all patients with drug-eluting stents presenting for non-cardiac surgical procedures over a three-year period in one centre. Twenty-four patients with drug-eluting stents inserted presented for 43 non-cardiac surgical procedures. Severe bleeding problems were encountered in one case. Three of 15 patients (20%) who ceased clopidogrel prior to surgery without alternative anti-thrombotic prophylaxis suffered myocardial infarction due to stent thrombosis. Four patients who received alternative anti-thrombotic prophylaxis did not suffer complications. All 19 patients who ceased clopidogrel remained on aspirin prior to surgery. Patients treated with drug-eluting stents for coronary artery stenosis represent a challenging group of patients for subsequent perioperative management. The risk of myocardial infarction when clopidogrel is stopped prior to surgery is 20%, if alternative anti-thrombotic prophylaxis is not used. This risk persists beyond one year after insertion of drug-eluting stents. Some treatments appear to be effective in reducing the risk of myocardial infarction.

Drug-eluting stents and late stent thrombosis

3 years after the first description of four cases of coronary stent thrombosis occurring late after insertion of drug-eluting stents,1 in today's Lancet Christoph Stettler and colleagues2 report a comprehensive meta-analysis of randomised trials that compared sirolimus and paclitaxel drug-eluting stents with each other or with bare-metal stents. They used a collaborative network analysis that combines studies that directly compare the two drug-eluting stents with studies in which each drug-eluting stent is compared with a bare-metal stent.

Endoprothèses coronaires et anesthésie

The coronary stents are widely used to prevent coronary restenosis after percutaneous coronary intervention. Dual antiplatelet therapy (acetyl salicylic acid and a thienopyridine-clopidogrel or ticlopidine) are prescribed at least during six weeks after conventional stent and six months after drug eluting stent insertion to prevent stent thrombosis. When an invasive procedure is required, a risk of stent thrombosis arises after stopping antiplatelet therapy and a risk of bleeding when continuing this treatment. Therefore, cardiologists should choose carefully the type of coronary stent before insertion and concerned physicians (anaesthesiologists, surgeons, cardiologists) should decide a perioperative strategy in these high-risk patients.

Cardiac Surgery in Patients with Drug Eluting Stents: The Risk of Stopping Clopidogrel

Recommendations for the duration of clopidogrel (Plavix®, Bristol Meyers Squibb, New York, NY) therapy following drug eluting stent (DES) insertion have been subject to recent criticism. Suggested recommendations for the continuation of clopidogrel have been extended to one year following DES insertion. However, patients with a previously inserted DES who now require cardiac surgery are requested to stop clopidogrel perioperatively. The safety of this practice is unclear. We report two cases of elective cardiac surgical intervention after the insertion of DES complicated by perioperative or intraoperative acute coronary ischemia attributed to DES closure.

Coronary artery stenting in a patient with angina pectoris caused by coronary artery dissection after blunt chest trauma

Coronary artery injury is an uncommon complication following blunt chest trauma. Although several types of coronary injuries after chest trauma have been reported previously, coronary artery dissection treated by stent insertion remains extremely rare. We report a case of a male who experienced recurrent angina due to blunt chest trauma induced coronary artery dissection, confirmed by intravascular ultrasound. The patient was successfully treated by percutaneous coronary intervention with drug-eluting stent insertion.

Safety of Magnetic Resonance Imaging One to Three Days After Bare Metal and Drug-Eluting Stent Implantation

Despite emerging evidence that magnetic resonance imaging (MRI) is safe within 8 weeks after bare metal coronary stenting, there are limited data on the safety of MRI imaging very early (1 to 3 days) after stent implantation and no published studies to date on the safety of MRI after insertion of drug-eluting stents (DESs). Forty-nine patients underwent cardiovascular MRI (1.5 T) at a median of 1 day after complex percutaneous coronary intervention. The average number of stents per patient was 2.2 +/- 1.1, and the average stent length per patient was 37.8 +/- 19.7 mm. In 15 of these patients > or =1 DES was used: paclitaxel DESs in 14 and sirolimus DESs in 1. In the DES group, the average number of stents was 1.75 +/- 1.0 per patient (3 patients received 3 DESs), and average DES length was 36.5 +/- 14.8 mm per patient. No acute thrombosis was recorded, and at 9-month clinical follow-up only 2 patients (4%) developed adverse events (1 target vessel restenosis and 1 nontarget vessel revascularization); these patients were in the non-DES group.