Antithrombotic therapy and cardiovascular outcomes after transcatheter aortic valve implantation in patients without indications for chronic oral anticoagulation: a systematic review and network meta-analysis of randomized controlled trials.

AIMS: As the antithrombotic regimen that may best prevent ischaemic complications along with the lowest bleeding risk offset following transcatheter aortic valve implantation (TAVI) remains unclear, we aimed to compare the safety and efficacy of antithrombotic regimens in patients without having an indication for chronic oral anticoagulation. METHODS AND RESULTS: We conducted a PROSPERO-registered (CRD42021247924) systematic review and network meta-analysis of randomized controlled trials evaluating post-TAVI antithrombotic regimens up to April 2022. We estimated the relative risk (RR) and 95% confidence intervals (95% CIs) using a random-effects model in a frequentist pairwise and network metanalytic approach. We included seven studies comprising 4006 patients with a mean weighted follow-up of 12.9 months. Risk of all-cause death was significantly reduced with dual antiplatelet therapy (DAPT) compared with low-dose rivaroxaban + 3-month single antiplatelet therapy (SAPT) (RR 0.60, 95% CI 0.41-0.88), while no significant reduction was observed with SAPT vs. DAPT (RR 1.02, 95% CI 0.67-1.58) and SAPT and DAPT compared with apixaban or edoxaban (RR 0.60, 95% CI 0.32-1.14 and RR 0.59, 95% CI 0.34-1.02, respectively). SAPT was associated with a significant reduction of life-threatening, disabling, or major bleeding compared with DAPT (RR 0.45, 95% CI 0.29-0.70), apixaban or edoxaban alone (RR 0.45, 95% CI 0.25-0.79), and low-dose rivaroxaban + 3-month SAPT (RR 0.30, 95% CI 0.16-0.57). There were no differences between the various regimens with respect to myocardial infarction, stroke, or systemic embolism. CONCLUSION: Following TAVI in patients without an indication for chronic oral anticoagulant, SAPT more than halved the risk of bleeding compared with DAPT and direct oral anticoagulant-based regimens without significant ischaemic offset.

Extended Anticoagulant Treatment with Full- or Reduced-Dose Apixaban in Patients with Cancer-Associated Venous Thromboembolism: Rationale and Design of the API-CAT Study.

Cancer-associated thrombosis (CT) is associated with a high risk of recurrent venous thromboembolic (VTE) events that require extended anticoagulation in patients with active cancer, putting them at risk of bleeding. The aim of the API-CAT study (NCT03692065) is to assess whether a reduced-dose regimen of apixaban (2.5 mg twice daily [bid]) is noninferior to a full-dose regimen of apixaban (5 mg bid) for the prevention of recurrent VTE in patients with active cancer who have completed ≥6 months of anticoagulant therapy for a documented index event of proximal deep-vein thrombosis and/or pulmonary embolism. API-CAT is an international, randomized, parallel-group, double-blind, noninferiority trial with blinded adjudication of outcome events. Consecutive patients are randomized to receive apixaban 2.5 or 5 mg bid for 12 months. The primary efficacy outcome is a composite of recurrent symptomatic or incidental VTE during the treatment period. The principal safety endpoint is clinically relevant bleeding, defined as a composite of major bleeding or nonmajor clinically relevant bleeding. Assuming a 12-month incidence of the primary outcome of 4% with apixaban and an upper limit of the two-sided 95% confidence interval of the hazard ratio <2.0, 1,722 patients will be randomized, assuming an up to 10% loss in total patient-years (ß = 80%; α one-sided = 0.025). This trial has the potential to demonstrate that a regimen of extended treatment for patients with CT beyond an initial 6 months, with a reduced apixaban dose, has an acceptable risk of recurrent VTE recurrence and decreases the risk of bleeding.