Having a residual shunt after percutaneous patent foramen ovale (PFO) closure was associated with an elevated risk of stroke or transient ischemic attack (TIA) recurrence years after the procedure, researchers found in a prospective cohort study.
The incidence of these events reached 2.32 per 100 patient-years with a shunt on transthoracic echocardiography (TTE) compared with 0.75 per 100 patient-years with a complete seal. The elevated risk persisted after adjustment for other factors (adjusted HR 3.01, 95% CI 1.59-5.69).
Whereas small residual shunts were not significantly linked to increased risk (HR 2.02, 95% CI 0.87-4.69), moderate or large residual shunts were (HR 4.50, 95% CI 2.20-9.20), reported MingMing Ning, MD, MMSc, of Massachusetts General Hospital and Harvard Medical School, and colleagues. Their findings were published online in the Annals of Internal Medicine.
Noting that stroke and TIA recurrence most often occurred within the first few years after PFO closure, Ning's team suggested that patients with moderate or large residual shunts undergo long-term follow-up of at least 5 years with a multidisciplinary team, with TTE with bubbles performed every 3 to 6 months during the first year and every 6 to 12 months thereafter to evaluate shunt size.
And because shunts can be expected to diminish over time as the closure device gets further epithelialized, stepping up antithrombotic treatment is reasonable until the shunt stabilizes, they added.