ASA Status May Predict Recurrent Stroke Risk in Patients With PFO

The risk for recurrent stroke was found to be better predicted by atrial septal aneurysm (ASA) status than by interatrial shunt size in patients with patent foramen ovale (PFO)-related ischemic stroke, according to study results published in the Journal of the American College of Cardiology.

The identification of patients at higher risk for recurrent stroke is critical, as they may benefit to a greater extent from PFO closure compared with patients at low risk.

In this pooled analysis, data for 898 patients (mean age, 45.3±11.8 years; 59.5% men) with PFO-associated stroke from 2 randomized controlled trials and 2 prospective observational studies, were examined. ASA status and shunt size were assessed in these patients with transesophageal and transthoracic echocardiography (TEE and TTE, respectively). The study’s primary outcome was time until recurrent stroke. Median follow-up duration was 3.8 years (interquartile range, 2.6-5.5 years).

A total of 178 patients (19.8%) in this cohort had ASA with large PFO, 71 patients (7.9%) had ASA with nonlarge PFO, 397 (44.2%) had no ASA with large PFO, and 252 (28.1%) had no ASA with nonlarge PFO. During the follow-up, 47 patients (5.2%) had a recurrent stroke (incidence rate, 1.3 per 100 person-years; 95% CI, 1.0-1.7) and 2 patients (0.2%) died.

There was significant heterogeneity in the association between shunt size and stroke recurrence across the 4 studies (P_interaction =.01). Multivariable analysis adjusted for age, PFO anatomy, antithrombotic therapy, and hypertension indicated a significant independent association between ASA status and recurrent stroke risk (adjusted hazard ratio [HR], 3.27; 95% CI, 1.82-5.86; P <.0001), but not between large PFO shunt size and stroke recurrence (average interstudy HR, 1.43; 95% CI, 0.50-4.03; P =.50).

Study strengths include the use of pooled patient data, the use of TEE and TTE in all patients, and the lack of apparent heterogeneity in the association between ASA status and recurrent stroke risk.

Study limitations include a low number of total events, a possible underpowering of the detection of milder associations, and an observational design.

“These results could help to better identify those patients with a high risk [for] stroke recurrence under medical therapy, who may derive the most benefit from PFO closure owing to a higher absolute risk reduction,” noted the authors.

Reference

Turc G, Lee J-Y, Brochet E, Kim JS, Song J-K, Mas J-L. Atrial septal aneurysm, shunt size, and recurrent stroke risk in patients with patent foramen ovale. J Am Coll Cardiol. 2020;75(18):2312-2320. doi:10.1016/j.jacc.2020.02.068