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Closure of a Patent Foramen Ovale PFO: An Intervention Sequence
Published on: December 23, 2022
Patent Foramen Ovale Closure in the Setting of Cryptogenic Stroke: A Meta-Analysis of Five Randomized Trials
Lohit Garg1, Affan Haleem1, Shweta Varade2
1Department of Cardiology, Lehigh Valley Health Network, Allentown, Pennsylvania.
Insights
Closing a patent foramen ovale (PFO) significantly reduces recurrent stroke risk in cryptogenic stroke patients. PFO closure offers a 58% lower chance of another stroke, providing a vital stroke prevention strategy.
Area of Science:
- Cardiology
- Neurology
- Interventional Cardiology
Background:
- The clinical benefit of patent foramen ovale (PFO) closure for cryptogenic stroke prevention remains debated.
- Recent randomized trials suggest PFO closure reduces recurrent stroke risk compared to medical therapy alone.
- This meta-analysis aims to clarify PFO closure's efficacy in preventing future strokes.
Purpose of the Study:
- To evaluate the effectiveness of patent foramen ovale (PFO) closure in preventing recurrent strokes.
- To synthesize data from multiple randomized clinical trials on PFO closure outcomes.
- To determine the impact of PFO closure on stroke recurrence rates in cryptogenic stroke patients.
Main Methods:
- Systematic literature search and meta-analysis of 5 large randomized clinical trials (CLOSE, RESPECT, Gore REDUCE, CLOSURE I, PC).
- Pooled data analysis of 3412 patients with cryptogenic stroke, comparing endovascular PFO closure with standard medical care.
- Primary outcome: reduction in stroke recurrence rate; secondary outcomes: TIA, composite outcomes, and atrial fibrillation events.
Main Results:
- Transcatheter PFO closure significantly reduced recurrent stroke rates compared to medication alone.
- Patients undergoing PFO closure had a 58% lower likelihood of experiencing another stroke.
- The number needed to treat (NNT) with PFO closure to prevent one recurrent stroke was 40.
Conclusions:
- Endovascular PFO closure is associated with a reduced risk of recurrent stroke in patients with prior cryptogenic cerebral infarct.
- Despite a small absolute stroke reduction, the findings are clinically significant due to the young age and lifetime risk of the patient population.
- PFO closure represents a clinically significant intervention for stroke prevention in select patients.
Background:
The clinical benefit of patent foramen ovale (PFO) closure after cryptogenic stroke has been a topic of debate for decades. Recently, 3 randomized controlled trials of PFO closure in patients with cryptogenic stroke demonstrated a significantly reduced risk of recurrent stroke compared with standard medical therapy alone. This meta-analysis was performed to clarify the efficacy of PFO closure for future stroke prevention in this population.
Methods:
A systematic literature search was undertaken. Published pooled data from 5 large randomized clinical trials (CLOSE, RESPECT, Gore REDUCE, CLOSURE I, and PC) were combined and then subsequently analyzed. Enrolled patients with cryptogenic stroke were assigned to receive standard medical care or to undergo endovascular PFO closure, with a primary outcome of reduction in stroke recurrence rate. Secondary outcomes included rates of transient ischemic attack (TIA), composite outcome of stroke, TIA, and death from all causes, and rates of atrial fibrillation events.
Results:
We analyzed data for 3412 patients. Transcatheter PFO closure resulted in a statistically significant reduced rate of recurrent stroke, compared with medication alone. Patients undergoing closure were 58% less likely to have another stroke. The number needed to treat with PFO closure to reduce recurrent stroke for 1 patient was 40.
Conclusions:
Endovascular PFO closure was associated with a reduced risk of recurrent stroke in patients with a prior cryptogenic cerebral infarct. Although the absolute stroke reduction was small, these findings are clinically significant, given the young age of this patient population and the patients' lifetime risk of recurrent stroke.
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