Long-Term Clinical Outcomes After Angiographically Defined Very Late Stent Thrombosis of Drug-Eluting Stent

Division of Cardiology, Department of Internal Medicine, Inje University Busan Paik Hospital, Busan, South Korea.
Clinical Cardiology (Impact Factor: 2.23). 09/2009; 32(9):526-9. DOI: 10.1002/clc.20648
Source: PubMed

ABSTRACT The advent of drug-eluting stent (DES) use has raised concerns regarding later occurring stent thrombosis, especially very late stent thrombosis (VLST), and little is known about long-term clinical outcomes after VLST occurrence.
Long-term clinical outcomes after detection of VLST may be poor.
We evaluated 3572 consecutive patients who received DES implantation from May 2004 to July 2007 at 3 hospitals. The primary outcomes were a composite of major adverse cardiac events (MACE) including cardiac death, myocardial infarction (MI), target-lesion revascularization (TLR), and target-vessel revascularization (TVR) after VLST occurrence.
We identified 19 patients (0.53%) with angiographically documented stent thrombosis developing over 1 year after DES implantation. The mean time to VLST occurrence was 899 days (899 +/- 353). Discontinuation of antiplatelet drugs was noted in 4 (21%) patients and the average duration of discontinuation was 4 days. Clinical presentations of VLST were mainly MI (17 patients, 89%). Balloon angioplasty was only performed in 12 patients (63%) and stent implantation in 7 patients (37%). Mean follow-up duration from VLST occurrence was 620 days (620+/-256). During clinical follow-up after VLST occurrence, no cardiac deaths or MIs were detected. Target-vessel revascularization was done in 2 (11%) patients and TLR in 1 patient (6%). Major adverse cardiac events occurred in 3 (16%) patients during long-term clinical follow-up.
Clinical presentation of VLST after DES implantation is associated with serious adverse events, such as MI. Long-term follow-up outcomes after VLST occurrence appear unfavorable and more data from larger studies are warranted.

  • [Show abstract] [Hide abstract]
    ABSTRACT: The application of coronary stents, especially drug-eluting stents (DESs), has made percutaneous coronary intervention (PCI) one of important therapeutic methods for CHD. DES has reduced the in-stent restenosis to 5%-9% and significantly improved the long-term prognosis of patients with CHD. The study aimed to investigate the long-term efficacy and safety of domestic drug-eluting stents (DESs) in patients with acute coronary syndrome (ACS).
  • [Show abstract] [Hide abstract]
    ABSTRACT: ACC/AHA/SCAI recommendations include dual anti-platelet therapy (aspirin and clopidogrel) for 12 months after drug-eluting stent percutaneous coronary intervention (DES PCI). Numerous case reports have emerged of "very late stent thrombosis" (VLST) (>1 year post-DES-PCI) even 1-5 years after DES-PCI manifesting with myocardial infarction and death when clopidogrel therapy was interrupted or stopped. We hypothesize that a novel regimen of alternate day clopidogrel would provide a cost-effective strategy to prevent VLST taking into account the known facts about clopidogrel pharmacodynamics, stent endothelialization and stent thrombosis. We hypothesized that the degree of anti-platelet effect required to prevent VLST decreases with time as the stent endothelializes-that is the "therapeutic threshold" required to prevent VLST decreases with time. The anti-platelet effect of clopidogrel lasts for 5-7 days. Typically, stent thrombosis on interruption of clopidogrel (with bare metal stents within first 30 days) occurs after 3-4 days signifying recovery of enough platelet function to produce stent thrombosis--recovery of platelet inhibition beyond the therapeutic threshold. Since the therapeutic threshold required to prevent VLST in DES after 1 year is much lower, this degree of platelet inhibition can be conceivably achieved with just administering clopidogrel on alternate days. EMPIRICAL DATA: We studied efficacy and safety of regimen of daily aspirin 81 mg and alternate-day clopidogrel 75 mg beyond 12 months after PCI with DES for prevention of VLST by following 347 patients for occurrence of death, myocardial infarction (MI), VLST, target vessel revascularization (TVR) and bleeding. There were no occurrence of major bleeding, VLST events or death. Long term dual anti-platelet therapy with aspirin 81 mg daily and clopidogrel 75 mg every other day beyond 12 months after PCI with DES may be a safe and efficacious cost-saving strategy to prevent VLST.
    Medical Hypotheses 11/2011; 78(1):166-70. DOI:10.1016/j.mehy.2011.10.018 · 1.15 Impact Factor