Patent Foramen Ovale and Stroke: A Review

Area of Science:

• Cardiology
• Neurology
• Medical Devices

Background:

• Patent foramen ovale (PFO) is an atrial opening present in ~25% of adults, often implicated in paradoxical embolism and strokes, particularly in younger individuals.
• Cryptogenic strokes, especially in patients under 60, have a high prevalence of PFO (~50%), necessitating methods to determine PFO's causal role.

Purpose of the Study:

• To evaluate the efficacy of PFO closure in reducing recurrent stroke in patients with cryptogenic stroke.
• To assess the utility of the Risk of Paradoxical Embolism (RoPE) score and PFO-Associated Stroke Causal Likelihood (PASCAL) classification in guiding PFO closure decisions.

Main Methods:

• Analysis of pooled data from 6 trials involving 3740 patients comparing PFO closure with medical therapy.
• Utilized the RoPE score for initial risk stratification and the PASCAL system (combining RoPE score and echocardiographic findings) for detailed causal assessment.

Main Results:

• PFO closure reduced annualized stroke incidence (0.47% vs 1.09% with medical therapy) over a median of 57 months.
• Patients classified as PASCAL 'probable' (younger, no risk factors, high-risk PFO anatomy) showed a significant 90% relative risk reduction in recurrent stroke with PFO closure.
• PASCAL 'unlikely' patients did not benefit from closure and experienced higher adverse event rates.

Conclusions:

• Percutaneous PFO closure is effective in substantially reducing stroke recurrence in carefully selected patients (<60 years) with cryptogenic stroke.
• The PASCAL classification system aids in identifying patients most likely to benefit from PFO closure, distinguishing them from those at higher risk of complications without benefit.