Long-term effectiveness and safety of transcatheter closure of patent foramen ovale compared with antithrombotic therapy alone: a meta-analysis of six randomised clinical trials and 3,560 patients with reconstructed time-to-event data

Aims: Although three recent trials have shown a significant stroke risk reduction after tPFOc, the individual statistical power is limited and the impact on pooled evidence needs to be explored. We aimed to pool data from available randomised clinical trials (RCT) to assess whether tPFOc is more effective and safe than antithrombotic therapy alone (ATA). Methods and results: Major electronic databases and tangential sources were searched. Six trials (3,560 patients) were identified. At a median follow-up of 3.6 (2.0-5.2) years (13,930 person-years), the risk of stroke was significantly lower after tPFOc compared with ATA (HR 0.28, 95% CI: 0.12-0.64, p=0.003). Significant heterogeneity was detected (I-2=66.1%), although single trials did not significantly influence the results. Reconstructed time-to-event data revealed that tPFOc benefits accrue after approximately one year and persist over time without significant variations (96.4% versus 88.0%; HR 0.25, 95% CI: 0.09-0.66, p=0.005; NNT=11). Although results showed a greater benefit in patients <45 years old, male, and with substantial shunt, interaction between subgroups was not significant. Trial sequential analysis showed that accumulated evidence appeared to be sufficient. However, tPFOc did not confer protection against transient ischaemic attack (TIA; HR 0.69, 95% CI: 0.31-1.54, p=0.365) and a significant excess in the risk of atrial fibrillation was observed (OR 4.99, 95% CI: 1.99-10.10, p<0.001), though generally early and transient. Major bleeding and migraine were comparable between treatments. Conclusions: Compared with ATA, tPFOc significantly reduces the risk of stroke at long-term follow-up but no benefit is observed in terms of TIA. Atrial fibrillation is higher after tPFOc, though generally early and transient. The risks of major bleeding and migraine are comparable between the groups.