Results Summary

What was the research about?

A patent foramen ovale, or PFO, is a small hole between the top two chambers of the heart that didn’t close correctly after birth. PFOs can raise the risk for stroke. For adults ages 18–60, about 10 percent of strokes caused by a blocked artery are related to a PFO. Among these patients, questions remain about what treatment works best to prevent future strokes.

In this study, the research team analyzed data from six clinical trials to compare two treatments for preventing future strokes among patients who had experienced a PFO-related stroke:

  • Medicines alone. Patients take medicines to prevent blood clots.
  • Surgical procedure to close the PFO, plus medicines. A doctor inserts a medical device through a vein to the PFO. The device closes the PFO and remains in the heart permanently. Patients also take medicines to prevent blood clots.

The research team looked at the risk of future strokes and at safety risks like serious adverse events. A serious adverse event occurs when medical care causes harm, such as having bleeding when taking blood thinners. The team also looked at treatment effects based on how likely it was that the PFO caused patients’ strokes. To determine likelihood, the team used existing scoring systems.

What were the results?

Compared with patients who took medicines alone, patients who also had surgery had a lower risk of future strokes.

Patients whose PFO was likely the cause of their stroke had a lower risk of future strokes with surgery plus medicines than with medicine alone, compared with patients whose PFO was not likely the cause of their stroke, based on the scoring systems.

Patients who had surgery had a higher risk of irregular heartbeat events within 45 days of surgery. But most patients’ heartbeats went back to normal over time. Other safety outcomes like bleeding or blood clots didn’t differ between the two treatments.

Who was in the study?

The study included data from 3,740 patients across six trials. The trials took place around the world from 2000 to 2017. Patients in the trials were ages 18 and older and had experienced a PFO-related stroke. The average age was 46, and 55 percent were men.

What did the research team do?

The research team combined and analyzed data from the six trials. The trials included patients with a PFO who had a stroke. Combining data from multiple trials provides more reliable results than data from single trials.

Researchers from the six trials provided input during this study.

What were the limits of the study?

The study couldn’t look at whether another stroke caused more disability, because some kinds of data were missing, such as how much help people needed at home.

Future research could compare how different medicines and types of medical devices reduce patients’ risk of having a stroke.

How can people use the results?

Patients who had a PFO-related stroke and their doctors can use these results when considering treatments for preventing future strokes.

Final Research Report

This project's final research report is expected to be available by November 2023.

Peer-Review Summary

The Peer-Review Summary for this project will be posted here soon.

Project Information

David M. Kent, MD, MS
Tufts Medical Center Inc.
The Systematic , Collaborative, PFO Closure Evaluation (SCOPE)

Key Dates

March 2023


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Last updated: January 25, 2023