Sustained risk of recurrent thromboembolic events in patients with patent foramen ovale and paradoxical embolism: long-term follow-up over more than 15 years.

BACKGROUND: Patients with patent foramen ovale (PFO) and cryptogenic stroke are at risk of recurrence. Therapeutic regimens range from no treatment to anticoagulation treatment to surgical or interventional closure. However, long-term follow-up is only available for up to 4 years.
METHODS: Among ~5,000 transesophageal echocardiographies in stroke/TIA-patients between 1988 and 1997, a PFO was found and considered a possible mediator for the neurological event in 97 patients. In these patients, the PFO was judged to be responsible for the neurological event. Patients with cardiac or other reasons for embolism were excluded. The therapy for stroke was chosen by the attending physician. Follow-up information was obtained through telephone interviews.
RESULTS: Follow-up was available for 86 patients (89%) with a mean period of 15.4 years (range, 11.2-25.9 years). Thirteen patients (15%) suffered from recurrent ischemic events (7 TIAs, 5 strokes, 1 peripheral embolism) after a mean period of 4.9 years. Four patients died, not associated with recurrent thromboembolism. The risk of recurrence was increased over the entire length of the mean follow-up period. The occurrence of recurrent events was not associated with differences in baseline data, the presence of ASA, PFO size or the chosen treatment.
CONCLUSION: In patients with paradoxical embolism, recurrent ischemic events are frequent despite medical therapy. These events are not limited to the early years after the index event; this long-term follow-up revealed a risk of occurrence over the entire follow-up. These patients have a sustained risk of recurrence, requiring lifetime protection, which should be considered in tailoring individual therapeutic strategies.