Risk of Perioperative Stroke in Patients With Patent Foramen Ovale: A Systematic Review and Meta-analysis

BACKGROUND: Patent foramen ovale (PFO) is a common congenital cardiac abnormality. Risk of stroke increases perioperatively, but the association of PFO with perioperative stroke risk remains unclear. We conducted a systematic review to inform the risk of perioperative stroke in patients with PFO undergoing surgery. METHODS: Embase, MEDLINE, and Cochrane databases were searched from inception to January 2020. We described methods used for establishing PFO and perioperative stroke diagnosis. We conducted meta-analyses to obtain pooled estimates for risk of stroke in patients with and without PFO in different surgical populations. RESULTS: Ten articles with a total of 20,858,011 patients met the eligibility criteria. Prevalence of PFO ranged from 0.06% to 1.4% based on International Classification of Diseases (ICD)-code diagnosis and from 10.4% to 40.4% based on echocardiography diagnosis. Perioperative stroke was observed in 0% to 25% of patients with PFO, and 0% to 16.7% without PFO. Studies that used echocardiography to diagnose PFO found no association between PFO and perioperative stroke. Studies that used ICD codes found strong association but were highly heterogeneous. PFO was not associated with a risk of perioperative stroke in cardiac and transplantation surgeries. While the adjusted odds ratios for stroke were substantial for orthopaedic, general, genitourinary, neurologic, and thoracic surgeries (with PFO status established based on ICD codes), data heterogeneity and quality of data create significant uncertainty. CONCLUSIONS: In conclusion, PFO is likely a risk factor for perioperative stroke in selected types of surgeries. However, this is based on very low-quality evidence. Rigorous prospective studies are needed to further investigate this relationship.