Atrial septal aneurysm contribution to the risk of cryptogenic stroke in patients with patent foramen ovale: A brief updated systematic review and meta-analysis

Atrial septal aneurysms (ASA) play an important role in cryptogenic stroke (CS) in patients with patent foramen ovale (PFO) but its contribution remains still not fully clarified in current literature. We sought to evaluate the contribution of ASA to the risk of CS in PFO patients based on studies published so far by means of a systematic review and metanalysis. A literature search, based on PubMed, Google Scholar and EMBASE databases, was performed to locate articles, published English language between 2000 and 2021, analysing the relationship between ASA and CS. The final research was conducted in September 2021. A total of 577 articles were retrieved after excluding duplicates. The initial screening excluded 215 articles because they did not meet inclusion criteria, leaving 362 articles to assess for eligibility. Subsequently, after evaluation of the full-text articles, 354 were excluded and 8 investigations met the inclusion criteria. Overall, 822 patients (mean age 48.3 years) were enrolled in the reviewed manuscripts with a prevalence of males of 48.7% and a normal distribution of the classical cardiovascular risk factors. ASA was present in 25.3% (208 subjects) of the patients enrolled, while the association of PFO+ASA was observed in 24.3% (200 subjects) of patients enrolled. PFO Patients with ASA were at higher risk of CS compared to those without (odd ratio: 3.38, 95% CI: 2.72-5.51, p<0.001, I2=4.3%,). The relative funnel plot did not show any evident asymmetry, confirming absence of publication bias. Our updated metanalysis enhances the importance of ASA contribution to stroke in patients with patent foramen ovale, being present in a third of patients with symptomatic PFO to whom it confers an additional odd ratio of 3.38.