Long-term risk of atrial fibrillation or flutter after transcatheter patent foramen ovale closure: a nationwide Danish study

The pathophysiology of patent foramen ovale and its related complications

The foramen ovale plays a vital role in sustaining life in-utero; however, a patent foramen ovale (PFO) after birth has been associated with pathologic sequelae in the systemic circulation including stroke/transient ischemic attack (TIA), migraine, high altitude pulmonary edema, decompression illness, platypnea-orthodeoxia syndrome (POS) and worsened severity of obstructive sleep apnea. Importantly, each of these conditions is most commonly observed among specific age groups: migraine in the 20 to 40s, stroke/TIA in the 30-50s and POS in patients >50 years of age. The common and central pathophysiologic mechanism in each of these conditions is PFO-mediated shunting of blood and its contents from the right to the left atrium. PFO-associated pathologies can therefore be divided into (1) paradoxical systemic embolization and (2) right to left shunting (RLS) of blood through the PFO. Missing in the extensive literature on these clinical syndromes are mechanistic explanations for the occurrence of RLS, including timing and the volume of blood shunted, the impact of age on RLS, and the specific anatomical pathway that blood takes from the venous system to the left atrium. Visualization of the flow pattern graphically illustrates the underlying RLS and provides a greater understanding of the critical flow dynamics that determine the frequency, volume, and pathway of flow. In the present review, we describe the important role of foramen ovale in in-utero physiology, flow visualization in patients with PFO, as well as contributing factors that work in concert with PFO to result in the diverse pathophysiological sequelae.

Transcatheter Structural Heart Disease Interventions and Concomitant Left Atrial Appendage Occlusion: A State-of-the-Art Review

Atrial fibrillation (AF) is the most common arrhythmia in patients with valvular heart disease, and it can be associated with adverse patient outcomes. However, the need of anticoagulation to counterbalance AF-associated stroke risk may further lead to suboptimal outcomes via increasing bleeding events, especially in high-risk individuals. Currently, the option to perform a concomitant to the index procedure for limiting stroke risk is emerging, in accordance to usual practice in cardiac surgery. In specific, as the vast majority of thrombi occur in the left atrial appendage, left atrial appendage occlusion (LAAO) is an established procedure for preventing ischemic stroke in patients with AF, while limiting anticoagulation-related bleeding events. Thus, the concept of combining an index procedure for a structural heart disease (SHD) with LAAO seems promising for preventing future stroke events. A combined procedure has been described in aortic stenosis (TAVI+LAAO), mitral regurgitation (TEER+LAAO) and atrial septal defects (PFO/ASD+LAAO). Evidence shows that a combined procedure can be safely performed in a "one-stop shop" fashion, without increased rates of procedural adverse events, with the potential to limit bleeding risk and provide prophylaxis against stroke events. Thus, this review is going to analyze indications and clinical evidence regarding the safety and efficacy of combined SHD+LAAO procedure, while also providing insights in gaps in knowledge and future directions for the evolvement of this field.

Determinants of adverse outcomes following patent foramen ovale closure in elderly patients

BACKGROUND

Limited data are available on transcatheter patent foramen ovale (PFO) closure outcomes in the elderly.

AIMS

Through this study, we aimed to determine the incidence and predictors of adverse events (recurrent cerebrovascular events [CVE] and atrial fibrillation [AF]) post-PFO closure in older patients with cryptogenic events.

METHODS

This multicentre international study included patients over 60 years undergoing PFO closure for cryptogenic thromboembolic events. A dedicated database compiled baseline, procedural, and follow-up data. Competing risk and adjusted outcome predictor analyses were conducted.

RESULTS

A total of 689 patients were included (median age 65 years, 41.2% female, mean Risk of Paradoxical Embolism [RoPE] score 4.5). The procedural success rate was 99.4%. After a median follow-up of 2 (interquartile range 1-5) years, 66 patients (9.6%) had died. CVE and stroke rates were 1.21 and 0.55 per 100 patient-years, respectively. Diabetes (hazard ratio [HR] 3.89, 95% confidence interval [CI]: 1.67-9.07; p=0.002) and atrial septal aneurysm (ASA; HR 5.25, 95% CI: 1.56-17.62; p=0.007) increased the CVE risk. New-onset AF occurred at a rate of 3.30 per 100 patient-years, with 51.3% within one month post-procedure. Older age (HR 1.05 per year, 95% CI: 1.00-1.09; p=0.023) and the absence of hypertension (HR 2.04, 95% CI: 1.19-3.57; p=0.010) were associated with an increased risk of AF.

CONCLUSIONS

Older patients undergoing PFO closure had a relatively low rate of CVE and new-onset AF after a median follow-up of 2 years. The presence of diabetes, ASA, and a more advanced age determined an increased risk of adverse clinical events. These factors may be considered in the clinical decision-making process regarding PFO closure in this challenging population.

Percutaneous suture-based patent foramen ovale closure: A state-of-the-art review

Percutaneous closure of a patent foramen ovale (PFO), a common variation of interatrial septum anatomy, is a commonly performed procedure in the catheterization laboratory to reduce the risk of recurrent stroke in selected patients and to treat other PFO-related syndromes. In the last twenty years, disc-based devices have represented the armamentarium of the interventional cardiologist; recently, suture-based devices have become an attractive alternative, despite limited data regarding their long-term performance. The present review gives an overview of the current evidence regarding suture-based PFO closure, the device's characteristics, the echocardiographic evaluation of the PFO anatomy, and recommendations for patient selection. A detailed procedural guide is then provided, and potential complications and future developments in the field are discussed.

Atrial Fibrillation After Patent Foramen Ovale Closure: Incidence, Pathophysiology, and Management

This comprehensive review explores the incidence, pathophysiology, and management of atrial fibrillation (AF) following percutaneous closure of patent foramen ovale (PFO). Although AF is considered a common adverse event post PFO closure, its incidence, estimated at <5%, varies based on monitoring methods. The review delves into the challenging task of precisely estimating AF incidence, given subclinical AF and diverse diagnostic approaches. Notably, a temporal pattern emerges, with peak incidence around the 14th day after closure and a subsequent decline after the 45th day, mimicking general population AF trends. The pathophysiological mechanisms behind post PFO closure AF remain elusive, with proposed factors including local irritation, device-related interference, tissue stretch, and nickel hypersensitivity. Management considerations encompass rhythm control, with flecainide showing promise, and anticoagulation tailored to individual risk profiles. The authors advocate for a personalized approach, weighing factors like age, comorbidities, and device characteristics. Notably, postclosure AF is generally considered benign, often resolving spontaneously within 45 days, minimizing thromboembolic risks. Further studies are required to refine understanding and provide evidence-based guidelines.

Artificial intelligence-enabled electrocardiogram (AI-ECG) does not predict atrial fibrillation following patent foramen ovale closure

Background

Atrial fibrillation (AF) is a known complication following patent foramen ovale (PFO) closure. AI-enabled ECG (AI-ECG) acquired during normal sinus rhythm has been shown to identify individuals with AF by noting high-risk ECG features invisible to the human eye. We sought to characterize the value of AI-ECG in predicting AF development following PFO closure and investigate key clinical and procedural characteristics possibly associated with post-procedural AF.

Methods

We performed a retrospective analysis of patients who underwent PFO closure at our hospital from January 2011 to December 2022. We recorded the probability (%) of AF using the Mayo Clinic AI-ECG dashboard from pre- and post-procedure ECGs. The cut-off point of ≥ 11 %, which was found to optimally balance sensitivity and specificity in the original derivation paper (the Youden index) was used to label an AI-ECG "positive" for AF. Pre-procedural transesophageal echocardiography (TEE) and pre- and post-procedure transcranial doppler (TCD) data was also recorded.

Results

Out of 93 patients, 49 (53 %) were male, mean age was 55 ± 15 years with mean post-procedure follow up of 29 ± 3 months. Indication for PFO closure in 69 (74 %) patients was for secondary prevention of transient ischemic attack (TIA) and/or stroke. Twenty patients (22 %) developed paroxysmal AF post-procedure, with the majority within the first month post-procedure (15 patients, 75 %). Patients who developed AF were not significantly more likely to have a positive post-procedure AI-ECG than those who did not develop AF (30 % AF vs 27 % no AF, p = 0.8).Based on the PFO-Associated Stroke Causal Likelihood (PASCAL) classification, patients who had PFO closure for secondary prevention of TIA and/or stroke in the "possible" group were significantly more likely to develop AF than patients in "probable" and "unlikely" groups (p = 0.034). AF-developing patients were more likely to have post-procedure implantable loop recorder (ILR) (55 % vs 9.6 %, p < 0.001), and longer duration of ILR monitoring (121 vs 92.5 weeks, p = 0.035). There were no significant differences in TCD and TEE characteristics, device type, or device size between those who developed AF vs those who did not.

Conclusions

In this small, retrospective study, AI-ECG did not accurately distinguish patients who developed AF post-PFO closure from those who did not. Although AI-ECG has emerged as a valuable tool for risk prediction of AF, extrapolation of its performance to procedural settings such as PFO closure requires further investigation.

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.

Incidence of atrial fibrillation in cryptogenic stroke with patent foramen ovale closure: protocol for the prospective, observational PFO-AF study

INTRODUCTION

After closure of patent foramen ovale (PFO) due to stroke, atrial fibrillation (AF) occurs in up to one in five patients. However, data are sparse regarding the possible pre-existence of AF in these patients prior to PFO closure, and about recurrence of AF in the long term after the procedure. No prospective study to date has investigated these topics in patients with implanted cardiac monitor (ICM). The PFO-AF study (registered with ClinicalTrials.gov under the number NCT04926142) will investigate the incidence of AF occurring within 2 months after percutaneous closure of PFO in patients with prior stroke. AF will be identified using systematic ICM. Secondary objectives are to assess incidence and burden of AF in the 2 months prior to, and up to 2 years after PFO closure.

METHODS AND ANALYSIS

Prospective, multicentre, observational study including 250 patients with an indication for PFO closure after stroke, as decided by interdisciplinary meetings with cardiologists and neurologists. Patients will undergo implantation of a Reveal Linq device (Medtronic). Percutaneous PFO closure will be performed 2 months after device implantation. Follow-up will include consultation, ECG and reading of ICM data at 2, 12 and 24 months after PFO closure. The primary endpoint is occurrence of AF at 2 months, defined as an episode of AF or atrial tachycardia/flutter lasting at least 30 s, and recorded by the ICM and/or any AF or atrial tachycardia/flutter documented on ECG during the first 2 months of follow-up.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee 'Comité de Protection des Personnes (CPP) Sud-Méditerranéen III' on 2 June 2021 and registered with ClinicalTrials.gov (NCT04926142). Findings will be presented in national and international congresses and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04926142.