Updating the evidence on patent foramen ovale closure versus medical therapy in patients with cryptogenic stroke: a systematic review and comprehensive meta-analysis of 2,303 patients from three randomised trials and 2,231 patients from 11 observational studies

Aims: We aimed at updating the evidence coming from randomised and observational studies of patent foramen ovale (PFO) closure compared to medical therapy in patients with cryptogenic stroke (CS). Methods and results: Comparative studies of PFO closure versus medical therapy published or presented through March 2013 were identified. Data from 2,303 patients in three randomised clinical trials (RCTs) and from 2,231 patients in 11 observational studies were included. In RCTs, the stroke hazard ratio (HR) for PFO closure versus medical therapy was 0.62 (95% confidence interval [CI]: 0.34-1.11; p=0.10 in the random effects model) with no significant heterogeneity or systematic bias. There was no significant difference in transient ischaemic attacks (TIA) (HR 0.77, 95% CI: 0.46-1.32; p=0.34) and no study-related deaths occurred. Pooling trials of the AMPLATZER PFO occluder device resulted in a significant reduction of stroke (HR 0.44, 95% CI: 0.20-0.95; p=0.04). Procedural success, new onset atrial fibrillation and cardiac thrombus were observed more frequently with the STARFlex compared with the AMPLATZER device. In observational studies, with high potential for baseline confounders, PFO closure was found to reduce the risk of recurrent stroke significantly (HR 0.23, 95% CI: 0.11-0.49; p<0.01 in the random effects model), with no significant effect on TIAs. Conclusions: In RCTs, unlike observational studies, PFO closure compared with medical therapy failed to achieve a statistically significant reduction in recurrent stroke. However, pooling RCTs of the AMPLATZER PFO occluder device yielded a statistically significant reduction in stroke over medical treatment that may warrant further investigation.