Recurrent cerebral ischemia in medically treated patent foramen ovale: a meta-analysis.
BACKGROUND
Among patients with a patent foramen ovale (PFO) and a prior cryptogenic ischemic stroke or TIA, the absolute and relative risk of recurrent events is unclear.


METHODS
We conducted a systematic review and meta-analysis of clinical studies in any language published up to February 2008. We included studies reporting original data on recurrent cerebrovascular events in patients with prior cryptogenic stroke or TIA and PFO. Two authors independently extracted data and evaluated study quality.


RESULTS
We identified 15 eligible studies, four with a non-PFO comparison group. In these four studies, the pooled relative risk (RR) for recurrent ischemic stroke or TIA in patients with vs without a PFO was 1.1 (95% confidence interval [CI] 0.8 to 1.5). For ischemic stroke, the pooled RR was 0.8 (95% CI 0.5 to 1.3). We tabulated the absolute rate of recurrent events in all 15 studies. The pooled absolute rate of recurrent ischemic stroke or TIA in patients with PFO was 4.0 events per 100 person-years (95% CI 3.0 to 5.1) while the rate of recurrent ischemic stroke was 1.6 events per 100 person-years (95% CI 1.1 to 2.1).


CONCLUSIONS
In medically treated patients with prior cryptogenic stroke, while the absolute rate of recurrent events is variable, available evidence does not support an increased relative risk of recurrent ischemic events in those with vs without a patent foramen ovale. Patent foramen ovale closure in these patients cannot be recommended until the results of ongoing clinical trials are reported.
Room 1242A, Foothills Medical Centre, 1403 29th Street NW, Calgary, AB, T2N 2T9 Canada.
M A
MA
Almekhlafi
S B
SB
Wilton
D M
DM
Rabi
W A
WA
Ghali
D L
DL
Lorenzetti
M D
MD
Hill
D000367:Age Factors; D002545:Brain Ischemia / Q000453:epidemiology* / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D054092:Foramen Ovale, Patent / Q000150:complications* / Q000453:epidemiology / Q000401:mortality / Q000628:therapy; D006801:Humans; D002546:Ischemic Attack, Transient / Q000453:epidemiology / Q000209:etiology / Q000401:mortality / Q000628:therapy; D012008:Recurrence; D012306:Risk; D020521:Stroke / Q000453:epidemiology* / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D016896:Treatment Outcome