Patent Foramen Ovale Closure in the Setting of Cryptogenic Stroke: A Meta-Analysis of Five Randomized Trials

A matching-adjusted indirect comparison of results from REDUCE and RESPECT-two randomized trials on patent foramen ovale closure devices to prevent recurrent cryptogenic stroke

AIMS

Two randomized clinical trials, REDUCE and RESPECT, demonstrated that patent foramen ovale (PFO) closure in combination with antithrombotic therapy was more effective for the prevention of recurrent ischemic stroke compared with antithrombotic therapy alone. The aim of this study was to determine the relative efficacy and safety of the PFO closure devices used in REDUCE (HELEX and CARDIOFORM Septal Occluders) compared with the device used in RESPECT (Amplatzer PFO Occluder).

METHODS

An unanchored matching-adjusted indirect comparison (MAIC) of the PFO closure arms of the REDUCE and RESPECT trials was performed using patient-level data from REDUCE weighted to match baseline characteristics from RESPECT. Comparisons of the following outcomes were made between the devices assessed in the trials: risk of recurrent ischemic stroke; recurrent ischemic stroke one year after randomization; any serious adverse event (SAE) related to the procedure or device; and atrial fibrillation or atrial flutter as an SAE related to the procedure or device.

RESULTS

After conducting the MAIC, baseline characteristics were well-matched between the two trials. Compared to RESPECT, PFO closure using the devices from REDUCE resulted in a hazard ratio of 0.46 (95% confidence interval [CI] 0.15-1.43; p = 0.17) for the risk of recurrent stroke. For the recurrence of stroke after one year, SAE related to the procedure or device, and atrial fibrillation or atrial flutter as SAE related to the procedure or device, the MAIC resulted in a rate difference of -0.68 (95%CI -2.06 to 0.70; p = .34), -1.29 (95%CI -3.82 to 1.25; p = .32), and -0.19 (95%CI -1.16 to 0.78; p = .71), respectively. These findings were consistent across scenario analyses.

CONCLUSIONS

This MAIC analysis found no statistically significant differences in efficacy and safety outcomes between PFO closure with the HELEX and CARDIOFORM Septal Occluders versus the Amplatzer PFO Occluder, as used in the REDUCE and RESPECT trials.

Cardiac and Echocardiographic Markers in Cryptogenic Stroke with Incidental Patent Foramen Ovale

OBJECTIVE

Some cardiac abnormalities could be a substrate for potential embolic source in cryptogenic stroke (CS). We evaluated whether cardiac and echocardiographic markers were associated with CS in patients with incidental patent foramen ovale (PFO) as defined using the Risk of Paradoxical Embolism (RoPE) score.

MATERIALS AND METHODS

Among 677 patients enrolled in a multicenter observational CS registry, 300 patients (44%) had PFOs detected by transesophageal echocardiography. They were classified into probable PFO-related stroke (RoPE score>6, n = 32) and stroke with incidental PFO (RoPE score≤6, n = 268) groups, and clinical characteristics, laboratory findings, cardiac and echocardiographic markers (i.e. brain natriuretic peptide, left atrial [LA] diameter, ejection fraction, early transmitral flow velocity/early diastolic tissue Doppler imaging velocity [E/e'], LA appendage flow velocity, spontaneous echo contrast, atrial septal aneurysm, substantial PFO, and aortic arch plaques), stroke recurrence, and excellent outcome (modified Rankin scale score <2) at discharge were compared. Risk factors for low RoPE scores were determined using multiple logistic regression analysis.

RESULTS

Higher brain natriuretic peptide levels (p = 0.032), LA enlargement (p < 0.001), higher E/e' (p = 0.001), lower LA appendage flow velocity (p < 0.001), non-substantial PFO (p = 0.021), and aortic arch plaques (p = 0.002) were associated with the low RoPE score group. Patients with high RoPE scores had excellent outcomes (58% versus 78%, p = 0.035). LA enlargement (age- and sex-adjusted odds ratio, 1.15; 95 % confidence interval, 1.00-1.32; p = 0.039) was an independent predictor of low RoPE scores.

CONCLUSIONS

Abnormal cardiac substrate could be associated with CS occurrence in a subset of patients with PFO. Patients with CS who had incidental PFO may be at risk of cardioembolism.

Are we there yet with patent foramen ovale closure for secondary prevention in cryptogenic stroke? A systematic review and meta-analysis of randomized trials

Background:

We performed a meta-analysis to evaluate the benefit of patent foramen ovale closure in stroke prevention.

Methods:

We searched Medline/PubMed, EMBASE, Web of Science and Cochrane central database for randomized control trials assessing the incidence of recurrent stroke after patent foramen ovale closure when compared to medical therapy. Pooled odds ratio and 95% confidence intervals were calculated using a random effects model. The heterogeneity among studies was tested using the χ² test and inconsistency was quantified using the I² statistic.

Results:

Our search strategy yielded 71 articles. We included five studies with a total of 3440 patients. Median age in the device group was 45 (43, 5.5) years and in the medical group was 45 (44.5, 46) years; 52% were male, 27.7% of patients had an atrial septal aneurysm, 25% had hypertension, and 20.5% had diabetes mellitus. The median follow-up time was 44 (34.5–50) months. The pooled odds ratio of recurrent stroke, transient ischemic attack and composite end point of stroke + transient ischemic attack + peripheral embolism in the patent foramen ovale closure versus medical therapy group were 0.4 (95% confidence interval 0.25–0.63, I² = 57.5%), 0.93 (95% confidence interval 0.61–1.42, I² = 0%), and 0.6 (95% confidence interval 0.44–0.82, I² = 0%), respectively. The incidence of atrial fibrillation was found to be significantly higher in the patent foramen ovale closure group with odds ratio of 6 (95% confidence interval 3.13–11.4, I² = 33.5%). On subgroup analysis, patent foramen ovale closure appeared to benefit males and patients with a large shunt. Number needed to treat to prevent one recurrent stroke with patent foramen ovale closure is 42. Number needed to harm to cause one atrial fibrillation with patent foramen ovale closure is 39.

Conclusion:

This meta-analysis of randomized trials concludes that percutaneous patent foramen ovale closure is effective in recurrent stroke prevention especially in males and in those with a large shunt.