Impact of Echocardiographic Parameters on Recurrent Stroke in the Randomized REDUCE PFO Cryptogenic Stroke Trial

Patent Foramen Ovale Closure in Older Patients With Stroke: Patient Selection for Trial Feasibility

BACKGROUND AND OBJECTIVES

Whether patent foramen ovale (PFO) closure benefits older patients with PFO and cryptogenic stroke is unknown because randomized controlled trials (RCTs) have predominantly enrolled patients younger than 60 years of age. Our objective was to estimate anticipated effects of PFO closure in older patients to predict the numbers needed to plan an RCT.

METHODS

Effectiveness estimates are derived from major observational studies (Risk of Paradoxical Embolism [RoPE] Study and Oxford Vascular Study, together referred to as the "RoPE-Ox" database) and all 6 major RCTs (Systematic, Collaborative, PFO Closure Evaluation [SCOPE] Consortium). To estimate stroke recurrence risk, observed outcomes were calculated for patients older than 60 years in the age-inclusive observational databases (n = 549). To estimate the reduction in the rate of recurrent stroke associated with PFO closure vs medical therapy based on the RoPE score and the presence of high-risk PFO features, a Cox proportional hazards regression model was developed on the RCT data in the SCOPE database (n = 3,740). These estimates were used to calculate sample sizes required for a future RCT.

RESULTS

Five-year risk of stroke recurrence using Kaplan-Meier estimates was 13.7 (95% CI 10.5-17.9) overall, 14.9% (95% CI 10.2-21.6) in those with high-risk PFO features. Predicted relative reduction in the event rate with PFO closure was 12.9% overall, 48.8% in those with a high-risk PFO feature. Using these estimates, enrolling all older patients with cryptogenic stroke and PFO would require much larger samples than those used for prior PFO closure trials, but selectively enrolling patients with high-risk PFO features would require totals of 630 patients for 90% power and 471 patients for 80% power, with an average of 5 years of follow-up.

DISCUSSION

Based on our projections, anticipated effect sizes in older patients with high-risk features make a trial in these subjects feasible. With lengthening life expectancy in almost all regions of the world, the utility of PFO closure in older adults is increasingly important to explore.

Comparative evaluation of intracardiac, transesophageal, and transthoracic echocardiography in the assessment of patent foramen ovale: A retrospective single-center study

INTRODUCTION

Certain patent foramen ovale (PFO) characteristics, such as a large right-to-left shunt (RLS) or atrial septal aneurysm, identify patients who may receive the highest clinical benefit from percutaneous PFO closure. This study aimed to compare intracardiac echocardiography (ICE) with standard echocardiographic imaging in the evaluation of high-risk PFO characteristics and RLS severity in patients with PFO-associated stroke.

METHODS

We conducted a retrospective review of all patients aged ≥18 years who underwent percutaneous PFO closure for PFO-associated stroke and received all three ultrasound-based cardiac imaging modalities and had interpretable results (N = 51). We then compared RLS severity, high-risk PFO characteristics, and the proportion of patients with a higher likelihood of PFO-associated stroke by ICE versus transthoracic echocardiogram (TTE) and transesophageal echocardiogram (TEE).

RESULTS

The final cohort had a mean (±SE) age of 48.4 (±1.8) years and was predominantly female (58.8%). ICE was more likely to identify a large RLS versus TTE/TEE combined (66.7% vs. 45.1%; p = 0.03). The use of ICE resulted in significantly more patients being reclassified as having a higher likelihood of PFO-associated stroke (TTE vs. TEE vs. ICE: 10.4% vs. 14.6% vs. 25%; p = 0.03). A high-quality bubble study was found to be the single most important factor associated with identifying a larger RLS across all modalities (ρ [p]; TTE: 0.49 [<0.001], TEE: 0.60 [<0.001], ICE: 0.32 [0.02]). The presence of a hypermobile septum was associated with significantly greater RLS on ICE (ρ [p]: 0.3 [0.03]), especially with poor quality bubble studies (ρ [p]: 0.49 [0.02]).

CONCLUSION

In this observational study of patients with PFO-associated stroke, ICE detected a large RLS more frequently than TTE and TEE; and reclassified some patients as having a higher likelihood of PFO-associated stroke.

Clinical Performance of the Gore Septal Occluder in Patent Foramen Ovale Closure in Different Septal Anatomies: 1-Year Results from a Single-Center Experience

BACKGROUND

PFO (Patent foramen ovale) is a common defect that affects about 25% of the population. Although its presence is asymptomatic in the majority of the cases, the remaining part becomes overt with different symptoms, including cryptogenic stroke. PFO closure is currently a widely available procedure in complex anatomy, with Amplatzer PFO Occluder (APO) being the most commonly used tool. However, the performance of another device, the GORE Septal Occluder (GSO), has not been completely explored with regard to different septal anatomies.

METHODS

From March 2012 to June 2020, 118 consecutive patients with an indication of PFO closure were treated using the GSO system, included in a prospective analysis, and followed. After 12 months, every patient underwent transcranial Doppler ultrasound to evaluate the effectiveness of treatment.

RESULTS

Of 111 patients evaluated, 107 showed effective PFO closure (96.4%), and 4 showed a residual shunt (3.6%). To better evaluate the device performance, the overall population was sorted into two clusters based on the echocardiographic characteristics. The main difference between groups was for PFO width (4.85 ± 1.8 vs. 2.9 ± 1 mm, p < 0.001) and PFO tunnel length (12.6 ± 3.8 vs. 7.2 ± 2, p < 0.001), allowing complex and simple anatomies to be identified, respectively. Regardless of the aforementioned cluster, the GSO performance required to reach an effective closure was independent of anatomy type and the chosen device size.

CONCLUSION

The GSO device showed a high closure rate at 1-year follow-up in patients, with at least one anatomical factor of complexity of PFO irrespective of the level of complexity itself.

Association of Atrial Septal Aneurysm and Shunt Size With Stroke Recurrence and Benefit From Patent Foramen Ovale Closure

Importance

The Patent Foramen Ovale (PFO)-Associated Stroke Causal Likelihood classification system combines information regarding noncardiac patient features (vascular risk factors, infarct topography) and PFO features (shunt size and presence of atrial septal aneurysm [ASA]) to classify patients into 3 validated categories of responsiveness to treatment with PFO closure. However, the distinctive associations of shunt size and ASA, alone and in combination, have not been completely delineated.

Objective

To evaluate the association of PFO closure with stroke recurrence according to shunt size and/or the presence of an ASA.

Design, Setting, and Participants

Pooled individual patient data from 6 randomized clinical trials conducted from February 2000 to October 2017 that compared PFO closure with medical therapy. Patients in North America, Europe, Australia, Brazil, and South Korea with PFO-associated stroke were included. Analysis was completed in January 2022.

Exposures

Transcatheter PFO closure plus antithrombotic therapy vs antithrombotic therapy alone, stratified into 4 groups based on the combination of 2 features: small vs large PFO shunt size and the presence or absence of an ASA.

Main Outcomes and Measures

Recurrent ischemic stroke.

Results

A total of 121 recurrent ischemic strokes occurred in the pooled 3740 patients (mean [SD] age, 45 [10] years; 1682 [45%] female) during a median (IQR) follow-up of 57 (23.7-63.8) months. Treatment with PFO closure was associated with reduced risk for recurrent ischemic stroke (adjusted hazard ratio [aHR], 0.41 [95% CI, 0.28-0.60]; P < .001). The reduction in hazard for recurrent stroke was greater for patients with both a large shunt and an ASA (aHR, 0.15 [95% CI, 0.06-0.35]) than for large shunt without ASA (aHR, 0.27 [95% CI, 0.14-0.56]), small shunt with ASA (aHR, 0.36 [95% CI, 0.17-0.78]), and small shunt without ASA (aHR, 0.68 [95% CI, 0.41-1.13]) (interaction P = .02). At 2 years, the absolute risk reduction of recurrent stroke was greater (5.5% [95% CI, 2.7-8.3]) in patients with large shunt and ASA than for patients in the other 3 categories (1.0% for all).

Conclusions and Relevance

Patients with both a large shunt and an ASA showed a substantially greater beneficial association with PFO closure than patients with large shunt alone, patients with small shunt and ASA, and patients with neither large shunt nor ASA. These findings, combined with other patient features, may inform shared patient-clinician decision-making.