Impact of residual platelet reactivity under clopidogrel treatment for lesions and the clinical outcome after drug-eluting stent implantation in patients with hemodialysis.

BACKGROUND

Hemodialysis (HD) patients are at high risk for adverse clinical outcomes after drug-eluting stent (DES) implantation. However, the impact of residual platelet reactivity under dual anti-platelet therapy in this subset of patients remains unclear.

METHODS

We enrolled 142 stable angina patients (194 lesions) treated with DES, who were taking aspirin and 75mg clopidogrel and had undergone 8-month angiography with optical coherence tomography (OCT). OCT findings and major adverse cardiac events (MACEs) at 1 year (cardiac death, acute coronary syndrome, target lesion and vessel revascularization, and stent thrombosis) were compared between 28 HD patients and 114 non-HD patients. Responsiveness to clopidogrel was assessed by measuring P2Y12 reaction unit (PRU) at 8 months.

RESULTS

PRU was significantly higher in HD patients than in non-HD patients (p=0.006), even though proportion of cytochrome P450 2C19 genotype was equivalent. HD patients had a significantly higher rate of thrombi formation (assessed using OCT) and MACEs than non-HD patients (thrombi: p=0.001; MACEs: p=0.0001). The PRU value was independently associated with MACEs in both groups. The optimal cutoff values of PRU for predicting MACEs were 235 for HD patients and 259 for non-HD patients.

CONCLUSIONS

HD was associated with a high residual platelet reactivity, which may contribute to the higher incidence of MACEs after DES implantation in HD patients. HD may be a patient profile that merits a more potent anti-platelet regimen.