Uninterrupted Oral Anticoagulant Therapy in Patients Undergoing Unplanned Percutaneous Coronary Intervention

Uninterrupted direct-acting oral anticoagulation in patients undergoing transradial percutaneous coronary procedures: The DOAC-NOSTOP study rationale and design

BACKGROUND

patients with atrial fibrillation (AF) under treatment with chronic oral anticoagulation (OAC) often require coronary angiography with or without percutaneous coronary intervention (PCI). Deciding the management of OAC during this periprocedural period requires balancing the risks of hemorrhage and thrombotic complications. Guidelines recommend an uninterrupted strategy in patients receiving Vitamin-K Antagonists (VKA). However, for patients undergoing coronary angiography or PCI while on direct oral anticoagulants (DOACs), withdrawal 12-24 h prior to the procedure is still recommended. This is based on expert opinions given the lack of evidence. Therefore, whether DOAC discontinuation prior to trans-radial coronary procedures should be the strategy of choice is a matter of debate and solid evidence is needed to guide clinical decision making.

METHODS

The DOAC-NOSTOP study is a prospective, single-arm, open-label study evaluating the safety of DOACs continuation in 200 patients undergoing transradial percutaneous coronary procedures. DOAC treatment will not be interrupted throughout the periprocedural period. Primary outcome will be Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 events, assessed at a 30-day follow-up.

CONCLUSIONS

The DOAC-NOSTOP is the first study prospectively assessing the risk of bleeding with uninterrupted DOAC in patients undergoing trans-radial percutaneous coronary procedures.

Continued non-vitamin K antagonist oral anticoagulants versus vitamin K antagonists during transcatheter aortic valve implantation

BACKGROUND

One-third of patients undergoing transcatheter aortic valve implantation (TAVI) have an indication for long-term oral anticoagulation (OAC).

AIMS

We aimed to investigate whether continued non-vitamin K antagonist oral anticoagulant (NOAC) therapy compared with continued vitamin K antagonist (VKA) therapy during TAVI is equally safe and effective.  Methods: Consecutive patients on OAC with either NOAC or VKA undergoing transfemoral TAVI at five European centres were enrolled. The primary outcome measure was a composite of major/life-threatening bleeding, stroke, and all-cause mortality at 30 days.

RESULTS

In total, 584 patients underwent TAVI under continued OAC with 294 (50.3%) patients receiving VKA and 290 (49.7%) patients receiving NOAC. At 30 days, the composite primary outcome had occurred in 51 (17.3%) versus 36 (12.4%) patients with continued VKA and with continued NOAC, respectively (odds ratio [OR] 0.68, 95% confidence interval [CI]: 0.43-1.07; p=0.092). Rates of major/life-threatening bleeding (OR 0.87, 95% CI: 0.52-1.47; p=0.606) and stroke (OR 1.02, 95% CI: 0.29-3.59; p=0.974) were not different between groups. In a multivariate Cox regression analysis, continued NOAC, compared with continued VKA, was associated with a lower risk for all-cause 1-year mortality (hazard ratio [HR] 0.61, 95% CI: 0.37-0.98; p=0.043). The analysis of the propensity score-matched cohort revealed similar results.

CONCLUSIONS

Continued NOAC compared with continued VKA during TAVI led to comparable outcomes with regard to the composite outcome measure indicating that continued OAC with both drugs is feasible. These hypothesis-generating results need to be confirmed by a dedicated randomised controlled trial.

Peri-interventional Triple Therapy With Dabigatran Improves Vasomotion and Promotes Endothelialization in Porcine Coronary Stenting Model

Objective: We evaluated the short and long-term effect of peri-interventional dabigatran therapy on vasomotion, endothelialization, and neointimal formation in a porcine coronary artery stenting model.

Background: Stenting of coronary arteries induces local inflammation, impairs vasomotion and delays endothelialization.

Methods: Twenty-eight animals underwent percutaneous coronary intervention (PCI) with drug eluting stents. Sixteen pigs started dabigatran therapy 4 days prior to PCI and continued for 4 days post-stenting, while 12 animals served as controls. Post-stenting dual antiplatelet therapy (75 mg clopidogrel and 100 mg aspirin) was continued in both groups until termination. Immediately post-stenting and at day 3 optical coherence tomography (OCT) was performed in all animals, followed by euthanasia of 8 dabigatran and 4 control animals. The remaining pigs (8 of each group) were followed up for 1 month, with control angiography and OCT. Tissue burden (degree of peri-strut structure—thrombus and/or fibrin) was evaluated. After euthanasia coronary arteries were harvested for in-vitro myometry and histology.

Results: Thrombin generation was lower (p < 0.001) and tissue burden (0.83 ± 0.98 vs. 3.0 ± 2.45; p = 0.031) was significantly decreased in dabigatran treated animals. After 3 days post-PCI endothelium-dependent vasodilation was significantly improved (77 ± 40% vs. 41 ± 31%, p = 0.02) in dabigatran animals. Neither quantitative angiography nor histomorphometry showed differences between the groups. Endothelialization was faster in the dabigatran group as compared with controls (p = 0.045).

Conclusion: Short-term peri-interventional triple therapy with dabigatran, aspirin, and clopidogrel led to an enhanced endothelium dependent vasodilation and faster endothelialization. However, neointimal formation 1-month after stent implantation was comparable between groups.