Aims: to investigate the relationship between Eustachian valve (EV) length and degree of atrial septal movement in patients with patent foramen ovale (PFO) and presumed paradoxical cerebral embolism. PFO is a well-established risk factor for cryptogenic stroke. However, due to the high prevalence of PFO, many of these are bystanders rather than true pathological entities. Other studies have sought to define which patients with PFO are particularly at risk of cryptogenic stroke by measuring various parameters of right atrial anatomy. We investigated the relationship between EV length and atrial septal movement.
Methods and results: measurements of EV length and atrial septal movement were made prospectively from 72 consecutive patients referred to our centre for PFO closure following presumed cryptogenic stroke, by intracardiac phased array echocardiography. The most significant finding from this study was that patients with fewer than 10 mm atrial septal movement had significantly longer EVs than those in whom there was >10 mm septal movement (P = 0.003). The mean EV length with >10 mm septal movement is 6.35 mm, and 13.33 mm with fewer than 10 mm movement. The prevalence of septal movement beyond 10 mm was significantly less in our series than in previously published papers.
Conclusion: we propose that while a large degree of atrial septal movement significantly increases propensity to cerebral embolism in patients with PFO, its absence does not negate this risk. We have shown that long EV may function independently from atrial septal movement to potentiate paradoxical embolism.