Incidence and correlates of drug-eluting stent thrombosis in routine clinical practice. 4-year results from a large 2-institutional cohort study

OBJECTIVES: We sought to determine the risk of late stent thrombosis (ST) during long-term follow-up beyond 3 years, searched for predictors, and assessed the impact of ST on overall mortality. BACKGROUND: Late ST was reported to occur at an annual rate of 0.6% up to 3 years after drug-eluting stent (DES) implantation. METHODS: A total of 8,146 patients underwent percutaneous coronary intervention with a sirolimus-eluting stent (SES) (n=3,823) or paclitaxel-eluting stent (PES) (n=4,323) and were followed up to 4 years after stent implantation. Dual antiplatelet treatment was prescribed for 6 to 12 months. RESULTS: Definite ST occurred in 192 of 8,146 patients with an incidence density of 1.0/100 patient-years and a cumulative incidence of 3.3% at 4 years. The hazard of ST continued at a steady rate of 0.53% (95% confidence interval [CI]: 0.44 to 0.64) between 30 days and 4 years. Diabetes was an independent predictor of early ST (hazard ratio [HR]: 1.96; 95% CI: 1.18 to 3.28), and acute coronary syndrome (HR: 2.21; 95% CI: 1.39 to 3.51), younger age (HR: 0.97; 95% CI: 0.95 to 0.99), and use of PES (HR: 1.67; 95% CI: 1.08 to 2.56) were independent predictors of late ST. Rates of death and myocardial infarction at 4 years were 10.6% and 4.6%, respectively. CONCLUSIONS: Late ST occurs steadily at an annual rate of 0.4% to 0.6% for up to 4 years. Diabetes is an independent predictor of early ST, whereas acute coronary syndrome, younger age, and PES implantation are associated with late ST.

Staphylococcus aureus: new evidence for intracellular persistence

Many reports have documented that Staphylococcus aureus can invade host cells and persist intracellularly for various periods of time in cell culture models. However, it is not clear whether intracellular persistence of S. aureus also occurs in the course of infections in whole organisms. This is a subject of intense debate and is difficult to assess experimentally. Intracellular persistence would provide S. aureus with an ideal strategy to escape from professional phagocytes and extracellular antibiotics and would promote recrudescent infection. Here, we present a brief overview of the mounting evidence that S. aureus has the potential to internalize and survive within host cells.