Adequate time in therapeutic INR range using triple antithrombotic therapy is not associated with long-term cardiovascular events and major bleeding complications after drug-eluting stent implantation.

BACKGROUND

Triple antithrombotic therapy increases the risk of bleeding events in patients undergoing percutaneous coronary intervention (PCI) compared with dual anti-platelet therapy (DAPT). However, whether warfarin control is associated with reduced cardiovascular events and major bleeding events in patients undergoing PCI with triple antithrombotic therapy is uncertain.

METHODS

We investigated 1207 consecutive patients who underwent PCI between 2004 and 2011. Major bleeding complications and major adverse cardiac and cerebrovascular events (MACCE) defined as all-cause death, acute coronary syndrome, target vessel revascularization, and stroke were compared between groups of patients who received either triple antithrombotic therapy or DAPT.

RESULTS

Triple antithrombotic therapy was administered to 95 (7.9%) patients. The mean international normalized ratio of prothrombin time (PT-INR) was 1.8. The target PT-INR level was set between 1.6 and 2.6 and the ratio (%) of time in the therapeutic range (TTR) was calculated. The median TTR was 78.4% (interquartile range, 67.4-87.6%). Kaplan-Meier survival curves showed that warfarin therapy was not associated with MACCE (p=0.89) and major bleeding (p=0.80). Multivariable Cox regression analysis revealed that triple antithrombotic therapy was not an independent predictor of MACCE and major bleeding.

CONCLUSIONS

Triple antithrombotic therapy does not increase the occurrence of MACCE and major bleeding complications, if the warfarin dose is tightly controlled with a lower INR.