Non-vitamin K antagonist oral anticoagulants (NOACs) post-percutaneous coronary intervention: a network meta-analysis.

BACKGROUND: Clinicians must balance the risks of bleeding and thrombosis after percutaneous coronary intervention (PCI) in people with an indication for anticoagulation. The potential of non-vitamin K antagonists (NOACs) to prevent bleeding complications is promising, but evidence remains limited. OBJECTIVES: To review the evidence from randomised controlled trials assessing the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) compared to vitamin K antagonists post-percutaneous coronary intervention (PCI) in people with an indication for anticoagulation. SEARCH METHODS: We identified studies by searching CENTRAL, MEDLINE, Embase, the Conference Proceedings Citation Index - Science and two clinical trials registers in February 2019. We checked bibliographies of identified studies and applied no language restrictions. SELECTION CRITERIA: We searched for randomised controlled trials (RCT) that compared NOACs and vitamin K antagonists for people with an indication for anticoagulation who underwent PCI. DATA COLLECTION AND ANALYSIS: Two review authors independently checked the results of searches to identify relevant studies, assessed each included study, and extracted study data. We conducted random-effects, pairwise analyses using Review Manager 5 and network meta-analyses (NMA) using the R package 'netmeta'. We ranked competing treatments by P scores, which are derived from the P values of all pairwise comparisons, and allow ranking of treatments on a continuous 0 to 1 scale. MAIN RESULTS: We identified nine RCTs that met the inclusion criteria, but four were ongoing trials, and were not included in this analysis. We included five RCTs, with 8373 participants, in the NMA (two RCTs compared apixaban to a vitamin K antagonist, two RCTs compared rivaroxaban to a vitamin K antagonist, and one RCT compared dabigatran to a vitamin K antagonist). Very low- to moderate-certainty evidence suggests little or no difference between NOACs and vitamin K antagonists in death from cardiovascular causes (not reported in the dabigatran trial), myocardial infarction, stroke, death from any cause, and stent thrombosis. Apixaban (RR 0.85, 95% CI 0.77 to 0.95), high dose rivaroxaban (RR 0.86, 95% CI 0.74 to 1.00), and low dose rivaroxaban (RR 0.80, 95% CI 0.68 to 0.92) probably reduce the risk of recurrent hospitalisation compared with vitamin K antagonists. No studies looked at health-related quality of life. Very low- to moderate-certainty evidence suggests that NOACs may be safer than vitamin K antagonists in terms of bleeding. Both high dose dabigatran (RR 0.53, 95% CI 0.29 to 0.97), and low dose dabigatran (RR 0.38, 95% CI 0.21 to 0.70) may reduce major bleeding more than vitamin K antagonists. High dose dabigatran (RR 0.83, 95% CI 0.72 to 0.96), low dose dabigatran (RR 0.66, 95% CI 0.58 to 0.75), apixaban (RR 0,67 , 95% Cl 0.51 to 0.88), high dose rivaroxaban (RR 0.66, 95% CI 0.52 to 0.83), and low dose rivaroxaban (RR 0.71, 95% CI 0.57 to 0.88) probably reduce non-major bleeding more than vitamin K antagonists. The results from the NMA were inconclusive between the different NOACs for all primary and secondary outcomes. AUTHORS' CONCLUSIONS: Very low- to moderate-certainty evidence suggests no meaningful difference in efficacy outcomes between non-vitamin K antagonist oral anticoagulants (NOAC) and vitamin K antagonists following percutaneous coronary interventions (PCI) in people with non-valvular atrial fibrillation. NOACs probably reduce the risk of recurrent hospitalisation for adverse events compared with vitamin K antagonists. Low- to moderate-certainty evidence suggests that dabigatran may reduce the rates of major and non-major bleeding, and apixaban and rivaroxaban probably reduce the rates of non-major bleeding compared with vitamin K antagonists. Our network meta-analysis did not show superiority of one NOAC over another for any of the outcomes. Head to head trials, directly comparing NOACs against each other, are required to provide more certain evidence.

Anticoagulation in Atherosclerotic Disease.

The prevention of atherothrombotic events is an essential therapeutic goal in the treatment of patients with arteriosclerotic diseases. After plaque rupture, a rapidly growing thrombus can lead to acute vascular occlusion and thus heart attack, stroke or limb ischaemia. The acute therapy combines anticoagulation and platelet inhibition. However, the only available therapy so far in the primary and secondary prevention of stable patients is the platelet inhibitors aspirin and clopidogrel. Despite the use of antiplatelet therapies, including aspirin and P2Y12-receptor antagonists, some patients with artery disease continue to experience recurrent cardiovascular ischaemic events due to excessive thrombin generation beyond the acute period. As a result, studies have tested non-vitamin K antagonist oral anticoagulants (NOACs), specifically the factor Xa inhibitors, either alone or in combination with antiplatelet therapy, in the management of arterial disease. For the first time, the COMPASS study investigated low-dose anticoagulation in stable coronary heart disease or peripheral arterial disease. The addition of 2 × 2.5 mg rivaroxaban to long-term aspirin therapy not only prevented cardiovascular death, myocardial infarction and stroke, but even reduced all-cause mortality by a relative 18% after a mean follow-up of 23 months. This benefit came at the expense of more gastrointestinal bleeding, which might be reduced by the addition of a proton pump inhibitor (investigations are ongoing). Interestingly, however, there was no increase in fatal or intracranial haemorrhages. Therefore, a new standard therapy for high-risk patients with atherosclerotic disease may become available in the near future.