Patent foramen ovale closure vs. medical therapy for recurrent stroke prevention: Evolution of treatment effect during follow-up.

Abstract

BACKGROUND

Little is known regarding changes in treatment effect over time associated with patent foramen ovale (PFO) closure among patients with embolic stroke of unknown origin.

METHODS

We reconstructed Kaplan-Meier curves for stroke from individual randomized trials comparing PFO closure vs. medical therapy among patients with embolic stroke. Random effects Cox-regression analyses were performed in order to estimate hazard ratios (HRs) with 95% confidence intervals (95%CIs).

RESULTS

A total of 2531 patients enrolled across 4 randomized trials were included. PFO closure was associated with a significant reduction in the risk of stroke at longest available follow-up (HR 0.18, 95%CI 0.06 to 0.59, P=0.005). However, recurrent stroke was already significantly reduced among patients randomized to PFO closure at 1-year (HR 0.40, 95%CI 0.20 to 0.80, P=0.010), with the treatment effect remaining consistent (P-for-interaction=0.356) between 1- and 5-year (HR 0.14, 95%CI 0.05 to 0.55, P=0.005) and beyond 5-year (HR 0.20, 95%CI 0.03 to 1.19, P=0.077).

CONCLUSIONS

Among patients with embolic stroke of unknown origin, PFO closure reduces the risk of stroke compared with medical therapy, with a significant reduction in recurrences starting already within 1-year after percutaneous PFO closure.