Comparing clinical outcomes of NOACs with warfarin on atrial fibrillation with Valvular heart diseases: a meta-analysis.

Background: Warfarin is the standard of care and NOAC (Novel oral anticoagulants) are a group of newer drugs for such purposes. NOAC has a generally better profile (Clear interaction, less side effect, require less monitoring). However, its efficacy on valvular atrial fibrillation remains unclear.

Method: We researched literature articles from Embase, Cochrane and PubMed. Then we meta-analysed these six articles to assess pooled estimate of relative risk (RR) and 95% confidence intervals (Cl) using random-effects model for stroke, systemic embolic event, major bleeding and all-cause mortality. Heterogeneity across study was tested with Cochran's Q Test and I Test. The bias of studies was first tested by examining the symmetry of Funnel Plot. Cochrane's Collaboration Tool was also used to report any presented bias.

Results: We collected 496 articles in total and finally we included six articles in our meta-analysis. For SSEE (Stroke, Systemic Embolic Event), the pooled relative risk showed a significantly better clinical outcome of NOAC (RR: 0.66; 95% CI: 0.46 to 0.95). However, there is no significant difference in major bleeding (RR: 0.714, 95% CI:0.46 to 1.11) and all-cause mortality (RR: 0.84, 95% CI: 0.58 to 1.21).

Conclusion: Compared to Warfarin, NOAC is significantly more protective against the embolic event, but no significant difference in lowering risk of major bleeding, all-cause mortality or all aspects of post-TAVI (Trans-catheter aortic valve implantation).