Long-term outcome of patients with antiphospholipid syndrome who undergo percutaneous coronary intervention.

OBJECTIVES: Patients with antiphospholipid antibody syndrome (APS) have an increased risk of atherothrombotic complications. There are limited data regarding the outcome of patients with APS who undergo percutaneous coronary intervention (PCI). Accordingly, we aimed to assess the long-term outcomes of these patients. METHODS: Nineteen APS patients who underwent PCI between the years 2003 and 2008 were compared to 380 patients who had undergone PCI during the same period (PCI group) and were matched by age (±5 years), gender, diabetes and hypertension. In addition, APS patients were compared to 1,458 patients with ST segment elevation myocardial infarction (MI) who were treated with PCI during the same period. Six-month to 4-year clinical outcomes were evaluated. RESULTS: The indication for PCI in the APS group was acute coronary syndrome in 52.6% of patients. After 1 year of follow-up, patients with APS had higher rates of target vessel revascularization than the other two groups, which translated to higher rates of major adverse cardiac events. There were no differences in MI or mortality rates between the groups. CONCLUSIONS: Patients with APS who undergo PCI have worse long-term clinical outcomes, driven by higher rates of revascularization, than other patients undergoing PCI. Further study is warranted to examine the mechanisms underlying these findings.

Clopidogrel tapering as a strategy to attenuate platelet rebound phenomenon in patients with bare-metal stents.

Early clustering of adverse cardiovascular events after abrupt cessation of clopidogrel has been reported in patients with acute coronary syndromes. A platelet rebound phenomenon may contribute to this increased thrombotic risk and a gradual drug tapering may attenuate this proposed platelet effect. Accordingly, we aimed to assess the effect of clopidogrel tapering on platelet reactivity. Twenty patients who underwent elective percutaneous coronary interventions with bare metal stents receiving 3 months of clopidogrel therapy (75 mg daily) were randomized to either of two discontinuation strategies: (1) Off group-abrupt drug cessation or (2) Tapering group-receiving clopidogrel 75 mg every other day for 4 weeks duration. Light transmission aggregometry, induced by ADP (5 and 10 µM) and collagen, was measured at four time-points (at baseline and 2, 4 and 6 weeks after randomization). In the off group, there was an early rise in platelet reactivity at 2 weeks after abrupt drug cessation compared to baseline, as measured by ADP 5 µmol/l (39.6 ± 2.8 vs. 67.9 ± 6.0, P < 0.001). The tapering regimen suppressed this rebound platelet aggregation by ADP 5 µmol/l at 2 weeks (P = 0.001) and 4 weeks (P = 0.001). Similar results were found with ADP 10 µmol/l and collagen agonists. Abrupt cessation of clopidogrel results in an early rise in platelet aggregability in patients with BMS that is attenuated by a tapering regimen. Clopidogrel administration every other day may achieve similar levels of platelet inhibition as full dose therapy. Further investigations evaluating clopidogrel tapering strategies and their potential clinical impact are warranted.