PFO Prevalence in the General Population
Patent foramen ovale (PFO) is present in approximately 15% to 25% of the adult population, with the most robust data coming from population-based studies using transesophageal echocardiography 1.
Key Prevalence Data
The prevalence estimates vary based on detection method and population studied:
- Autopsy studies: 27% prevalence in patients with normal hearts 2
- Transthoracic echocardiography: 14.9% in stroke-free subjects over age 39 2
- Transesophageal echocardiography: 24.3% in randomly sampled adults ≥45 years old from the Olmsted County SPARC study 2
- Consensus range: 15-25% across multiple population studies 1
Important Clinical Context
The prevalence appears to decline with age 2, meaning younger adults have higher rates than older adults. This age-related decline is an important consideration when interpreting individual patient findings.
Detection Method Matters
Transesophageal echocardiography detects PFO at higher rates (24.3%) compared to transthoracic approaches (14.9%) because of superior sensitivity 2. This technical difference explains some variation in reported prevalence rates across studies.
Contrast with Stroke Populations
While 15-25% of the general population has a PFO, the prevalence is substantially higher in patients with cryptogenic stroke—approximately 34-46% depending on age group 2, 1, 2. This elevated prevalence in stroke patients, particularly those under 55 years old, supports the causal relationship between PFO and paradoxical embolism.
The most recent comprehensive review confirms that PFO is present in approximately 25% of all adults 3, which aligns with the guideline consensus of 15-25% 1.