Background:
We aimed to compare the efficacy and safety of clopidogrel monotherapy versus aspirin monotherapy beyond 12 months after PCI in high-risk patients during the chronic maintenance period.
Methods:
8,377 consecutive patients at high risk for both bleeding and thrombosis were identified from the prospective Fuwai PCI Registry if they satisfied one clinical and one angiographic criterion (TWILIGHT trial inclusion criteria). We studied on patients who received antiplatelet (aspirin or clopidogrel) monotherapy longer than 12 months and were free from ischemic and bleeding events at 12-month post-PCI without extended duration of DAPT. The primary endpoint was net adverse clinical events (NACE, a composite of all-cause death, myocardial infarction (MI), definite/probable stent thrombosis, stroke, or BARC bleeding type 2, 3 or 5) from 12 to 30 months. The key secondary endpoints were MACCE and major or clinically relevant nonmajor bleeding (BARC type 2, 3 or 5).
Results
Of 7,392 high-risk patients that were event-free after the first year and adherent to DAPT, 5,664 patients who received antiplatelet monotherapy (clopidogrel monotherapy: n=1,974 and aspirin monotherapy: n=3690) were included in the present analysis. Between 12 and 30 months, the net adverse clinical events were lower with clopidogrel monotherapy compared to aspirin monotherapy (2.3% vs. 4.4%; Plog-rank=0.001; adjusted HR: 0.550, 95% CI: 0.384-0.788; P=0.001). Clopidogrel monotherapy was associated with lower risk for MACCE (adjusted HR: 0.447, 95% CI: 0.278-0.718; P=0.001), as well as lower incidence rates of all-cause death (0.6% vs. 1.5%, Plog-rank=0.023), MI (0.4% vs. 0.9%, Plog-rank=0.058), and stroke (0.4% vs. 1.3%, Plog-rank=0.008). The difference in risk between the groups was similar for major or clinically relevant nonmajor bleeding (incidence, 1.3% in clopidogrel monotherapy and 1.7% in aspirin monotherapy; adjusted HR: 0.738; 95% CI, 0.429-1.272).
Conclusions
After 12-month post-PCI in high-risk event-free patients, clopidogrel monotherapy was associated with reduced risk of NACE and MACCE, and a numerical decrease in major or clinically relevant nonmajor bleeding, compared with aspirin monotherapy during the chronic maintenance period.