Pathophysiology and Management of Arrhythmias Associated with Atrial Septal Defect and Patent Foramen Ovale

Refractory atrial tachycardia after transcatheter closure of an atrial septal defect, successfully treated by catheter ablation with transseptal approach via the side of the device

Atrial tachyarrhythmias occurring after transcatheter atrial septal defect closure are not uncommon; however, those related to device stimulation are rare. Herein, a case involving a 24-year-old female, who developed drug-refractory atrial tachycardia during the early postoperative period, is reported. The results of electroanatomical mapping could eventually be obtained from both atria. They revealed a focal pattern, and the earliest site was located on the left atrial side of the superior atrial septum, between the left and right atrial discs of the device. An ablation catheter was inserted through the side of the device into the left atrial septum, and cauterization successfully achieved recovery of the sinus rhythm without device dislodgement.

Learning objective

Atrial tachyarrhythmia related to mechanical stimulation with an atrial septal defect closure device in the early perioperative period is a rare complication. Catheter ablation with transseptal approach through the side of the device might be an option, although careful attention should be paid to the risk for device dislodgement.

Flecainide to prevent atrial arrhythmia after patent foramen ovale closure, Rationale and design of the randomized AFLOAT study

INTRODUCTION

Atrial arrhythmia is the most common complication of patent foramen ovale (PFO) closure. The real incidence of post-PFO closure atrial arrhytmia and whether this complication can be prevented is unknown.

METHODS/DESIGN

The Assessment of Flecainide to Lower the PFO closure risk of Atrial fibrillation or Tachycardia (AFLOAT) trial is a prospective, national, multicentre, randomized, open-label, superiority trial with a blind evaluation of all the endpoints (PROBE design). A total of 186 patients are randomized in a 1:1:1 ratio immediately after PFO closure to receive Flecainide (150 mg per day in a single sustained-release (SR) dose) for 6 months (Group 1), Flecainide (150 mg per day in a single SR dose) for 3 months (Group 2), or no additional treatment (standard of care) for 6 months (Group 3). The primary endpoint is the percentage of patients with at least one episode of symptomatic or asymptomatic atrial arrhythmia episode (≥30 s) recorded within 3 months after PFO closure on long-term monitoring with an insertable cardiac monitor. Whether 3 months of treatment is sufficient compared to 6 months will be analysed as a secondary objective of the study.

CONCLUSION

AFLOAT is the first trial to test the hypothesis that a short treatment with oral Flecainide can prevent the new-onset of atrial arrhythmia after PFO closure.

CLINICAL TRIAL REGISTRATION

NCT05213104 (clinicaltrials.gov).

Experimental study of the bilateral asymmetric single-rivet occluder device for transcatheter patent foramen ovale closure with reserved interatrial septal puncture area

Purpose

To evaluate a noval bilateral asymmetric single-rivet occluder with reserved interatrial septal puncture area for treating patent foramen ovale (PFO).

Materials and methods

The study established a pig model of patent foramen ovale (PFO) by puncturing the oval fossa and then performing high-pressure balloon dilation. A specially designed bilateral asymmetric occluder for the reserved interatrial septal puncture area was then. used to close the PFO through catheter-based intervention. The pigs were kept for 3 months before undergoing a second catheter-based intervention, involving interatrial septal puncture using a newly developed occluder in the reserved interatrial septal puncture area. During 6 months, the experimental pigs underwent assessment using digital subtraction angiography (DSA), echocardiography, and histological evaluation.

Results

A patent foramen ovale (PFO) model was successfully established in 6 pigs using the puncture atrial septum high-pressure balloon dilation method. The diameter of the unclosed PFO was measured (3.56 ± 0.25 mm). Using the newly developed occluder device, all 6 pigs with unclosed PFO underwent successful catheter-based closure surgeries, with intraoperative and postoperative transesophageal echocardiography showing excellent device positioning and complete closure without residual shunting. After 3 months of implantation, the catheter-based interatrial septal puncture was performed through the reserved interatrial septal puncture area, and all procedures were successful. Immediately following euthanasia, a histological examination revealed intact and undamaged occluder devices with visible puncture holes in the reserved interatrial septal puncture area. No fracture of the nitinol wire was observed, and the surface of the occluder device showed coverage of endothelial and connective tissues. Utilizing a bilateral asymmetric single-rivet occluder device implanted through the reserved interatrial septal puncture area has proven effective in closing PFO. After implantation, the occluder device allows subsequent interatrial septal puncture procedures through the reserved area.

Conclusion

The novel occluder device demonstrated excellent closure performance, biocompatibility, and puncturability in the experiment. This indicates the feasibility of conducting further catheter-based interventions on the interatrial septum.

Arrhythmic Risk and Treatment after Transcatheter Atrial Septal Defect Closure

Atrial septal defect (ASD) represents the most common congenital heart defect identified in adulthood. Atrial and ventricular geometric remodeling due to intracardiac shunt increase the risk of arrhythmias, especially atrial fibrillation (AF). Clinical, echocardiography, electrocardiogram, and device-related predictors may be used to assess the risk of atrial arrhythmias after ASD closure. The underlying mechanisms in these patients are complex and at least in part independent of the structural remodeling secondary to hemodynamic overload. Device closure of the ASD itself and its timing impact future arrhythmia risk, as well as posing a challenge for when transseptal puncture is required. Sudden cardiac death (SCD) risk is higher than in the general population and an implantable cardioverter-defibrillator (ICD) may be indicated in selected cases.

Fenestration: Integrating Wings Into the Atrial Septal Occluder for Navigating a Challenging Terrain

Background Atrial septal defect (ASD) closure with significant left-to-right shunt and concurrent comorbidities poses challenges for intervention. A fenestrated atrial septal defect (FASD) device is a viable option for patients who cannot undergo complete occlusion due to hemodynamic and medical reasons. This study explores the use of FASD occluders in patients with secundum ASD and associated comorbidities where complete occlusion is difficult. Methodology This retrospective study collected the details of patients recommended for FASD closure diagnosed with significant secundum ASD and who had additional comorbidities between July 2015 and July 2023 in a tertiary cardiac center in eastern India. Among this cohort, patients who underwent FASD device placement were subjected to a comprehensive analysis. Results In total, 16 patients diagnosed with secundum ASD, characterized by significant left-to-right shunt and concurrent comorbidities, were considered for FASD closure during the study period. Ultimately, 13 patients (first group) underwent fenestrated atrial septal occluder implantation. The average age was 45.07 years, with the majority being females (n = 9). Comorbidities among this cohort included substantial left ventricular diastolic dysfunction (n = 7), left ventricular diastolic dysfunction coupled with moderate pulmonary hypertension (n = 1), severe pulmonary hypertension (n = 1), severe pulmonary valvular stenosis with right ventricular diastolic dysfunction (n = 2), and systemic lupus erythematosus (SLE) (n = 2). From this cohort, three patients did not undergo the intervention. The second group consisted of an elderly patient with severe left ventricular diastolic dysfunction, a young adult with a history of left atrial arrhythmia, and a child with Duchenne muscular dystrophy (DMD). The average ASD size among patients who underwent the intervention was 26.38 mm, with a thick-to-thick dimension measuring 31.15 mm. The procedure was successful in all 13 patients, with the most frequently used device being a 34 mm occluder (range = 28-40 mm). All devices, excluding the initial one, were custom-made atrial septal occluders (Lifetech Scientific). Among the patients, 12 exhibited left-to-right fenestration flow, while one patient experienced fenestration constriction, likely due to occluder overcrowding. The first patient had a handmade 5 mm fenestration in a 40 mm Amplatzer septal occluder, which got closed off at the one-year follow-up. The procedure was well-tolerated hemodynamically in all patients, with no major complications during the peri-procedural period. Short-term follow-up indicated favorable patient progress. Conclusions FASD closure emerges as a pivotal alternative for intricate scenarios involving secundum ASD coupled with concurrent comorbidities, offering individualized tailored solutions. Alongside the conventional associated comorbidities, such as left ventricular diastolic dysfunction and pulmonary hypertension, FASD devices hold the potential to extend their benefits to patients grappling with other complexities, including severe pulmonary valvular stenosis, SLE, predisposition to left atrial arrhythmia, and conditions like DMD. Ensuring meticulous evaluation of patient suitability and providing ongoing vigilant care becomes paramount for achieving optimal outcomes. The validation of these findings and the broadening of the comprehension of this approach necessitate further comprehensive investigations.

In vivo study of a reserved atrial septal puncture area patent foramen ovale occluder

PURPOSE

After patent foramen ovale interventional closure, puncture of the interatrial septum through the occluder is difficult but sometimes needed for further interventional treatment. This paper presents findings from an in vivo experimental study of a reserved atrial septal puncture area patent foramen ovale occluder.

MATERIALS AND METHODS

A patent foramen ovale model was established in canines using trans-septal puncture of the fossa ovale and high-pressure balloon dilation. Then, patent foramen ovale closure was performed with a reserved atrial septal puncture area and all canines were raised for 3 months. Then, the occluder was crossed and left atrial angiography was performed on the septal area with the occluder. Finally, DSA angiography, echocardiography, and histology were used to evaluate the performance and feasibility of the reserved atrial septal puncture area.

RESULTS

A patent foramen ovale model was successfully established in 10 canines using the atrial septal puncture method. The average diameter of the patent foramen ovale was 3.77 ±0.19 mm, and the patent foramen ovale was successfully closed in all canines using a reserved atrial septal puncture area. As assessed using transoesophageal echocardiography, the new occluder exhibited an ideal position and was occluded entirely without a residual shunt intraoperatively and postoperatively. A 100% success rate of atrial septum puncture was achieved across the new occluder. The occluders were completely endothelialised 3 months post-implantation.

CONCLUSIONS

The reserved atrial septal puncture area was effective in patent foramen ovale closure and exhibited positive sealing performance and biological compatibility. Trans-septal puncture was feasible and effective after reserved atrial septal puncture area patent foramen ovale closure.

Early and Late Postoperative Tachyarrhythmias in Children and Young Adults Undergoing Congenital Heart Disease Surgery

The population of patients with congenital heart disease is constantly growing with an increasing number of individuals reaching adulthood. A significant proportion of these children and young adults will suffer from tachyarrhythmias due to the abnormal anatomy, the hemodynamic burden, or as a sequela of surgical treatment. Depending on the underlying mechanism, arrhythmias may arise in the early postoperative period (hours to days after surgery) or in the late postoperative period (usually years after surgery). A good understanding of the electrophysiological characteristics and pathophysiological mechanisms is therefore crucial to guide the therapeutic approach. Here, we synthesize the current state of knowledge on epidemiological features, risk factors, pathophysiological insights, electrophysiological features, and therapy regarding tachyarrhythmias in children and young adults undergoing reparative surgery for congenital heart disease. The evolution and latest data on treatment options, including pharmacological therapy, ablation procedures, device therapy decision, and thromboprophylaxis, are summarized. Finally, throughout this comprehensive review, knowledge gaps and areas for future research are also identified.

Amplatzer Patent Foramen Ovale Occluder Device-Related Complications

Patent foramen ovale (PFO) is a standard variant that is present in 25% of the whole adult population. In a certain population, PFO can lead to cerebrovascular accidents. Mechanism of cerebrovascular accidents can be by paradoxical embolization from the right circulation or in situ thrombosis. Diagnosis of a PFO-responsible cerebrovascular accident is based on a thorough work-up to exclude other possible etiologies and detect PFO on trans-thoracic or trans-esophageal echocardiography with bubble study and/or Doppler. Over the last few years, multiple studies have supported that percutaneous PFO closure is superior to medical therapy in the secondary prevention of cerebrovascular accidents. However, numerous adverse events have been linked to PFO closure devices in general compared to medical therapy as new-onset atrial fibrillation, residual shunt, device-related thrombus, bleeding, deep vein thrombosis, pulmonary embolism, and inter-atrial septal erosions. Amplatzer device is one of the PFO occluder devices approved by the FDA. Device-related adverse events have been addressed by comparing the Amplatzer device with other PFO occluder devices. Based on the new data, we expect to see more complications related to PFO closure in the coming few years. We reviewed different studies that looked at the PFO closure-related complications and the trials comparing adverse events in the Amplatzer PFO occluder device compared to other devices. Amplatzer PFO occluder device is either superior or non-statistically different from other PFO occluder devices related to new-onset atrial fibrillation and residual shunt. More studies are needed to address the other less common adverse events. Since many of the device-related complications appear many years after device placement, a long-term follow-up is recommended.

Percutaneous Patent Foramen Ovale Closure in Patients with Cryptogenic Stroke or Transient Ischemic Attack: A Retrospective Study

Background

Patent foramen ovale (PFO) is associated with cryptogenic stroke (CS). Transcatheter closure of PFO is superior to pharmacotherapy for patients with CS or transient ischemic attack (TIA). More evidence is needed to evaluate the efficacy and safety of PFO closure in Chinese patients.

Methods

This study enrolled ten CS patients and two TIA patients (mean age of 40.8 ± 9.7 y), including seven males (58%) and five females (42%) who underwent PFO closure in our center from January 2017 to July 2019. Baseline data, imaging data, and RoPE (Risk of Paradoxical Embolism) score were collected retrospectively. The preprocedural assessment and percutaneous transcatheter PFO closure were described in detail. The perioperative complications and follow-ups were recorded from all patients.

Results

Among ten patients with CS, eight patients had a RoPE score of >6 and two patients had a RoPE score of 6. MRI confirmed multiple infarcts in seven cases, and infarct involving the cortex in nine cases. Abnormal ECG was found in three patients and abnormal Echo in four patients. Right-to-left shunt (RLS) was detected in all the patients by cTCD or cTTE. To be specific, RLS was observed in nine of the ten TEE-detected patients. No case had PFO complicated with atrial septal aneurysm (ASA). The success rate of PFO closure was 91.6%. No serious perioperative complications were observed. During a mean time of 26.5 ± 8 months (15-41 months) of follow-up, no recurrent cerebral infarction, TIA, or thromboembolism were detected in postoperative patients.

Conclusions

PFO closure is safe and effective in the treatment of Chinese patients with CS or TIA.

Crochetage sign may predict late atrial arrhythmias in patients with secundum atrial septal defect undergoing transcatheter closure

BACKGROUND

Atrial arrhythmias are well-known complications of atrial septal defect (ASD), and associated with substantial morbidity. After ASD closure, right atrial and ventricular enlargement regresses, however, the risk of atrial arrhythmia development continues. In this study, we aimed to investigate the relationship between the Crochetage sign, which is a possible reflection of heterogeneous ventricular depolarization due to long-term hemodynamic overload, and the development of late atrial arrhythmia after ASD closure.

METHODS

This retrospective study included a total of 314 patients (mean age: 39.5 (30-50) years; male: 115) who underwent percutaneous device closure for secundum ASD. The study population was divided into two groups according to the presence or absence of the Crochetage sign. The Crochetage sign was defined as an M-shaped or bifid pattern notch on the R wave in one or more inferior limb leads. Cox-regression analysis was performed to determine independent predictors of late atrial arrhythmia development.

RESULT

Fifty-seven patients (18.1%) presented with late atrial arrhythmia. Of these 57 patients, 30 developed new-onset atrial fibrillation/atrial flutter (AF/AFL), and 27 patients with pre-procedure paroxysmal AF/AFL had a recurrence of AF/AFL during follow-up. History of paroxysmal AF/AFL before the procedure (HR: 4.78; 95% CI 2,52-9.05; p < 0.001), the presence of Crochetage sign (HR: 3.90; 95% CI 2.05-7.76; p < 0.001), and older age at the time of ASD closure (HR: 1.03; 95% CI 1.01-1.06; p = 0.002) were found as independent predictors for late atrial arrhythmia.

CONCLUSION

The presence of Crochetage sign may be used to predict the risk of late atrial arrhythmia development after transcatheter ASD closure.

Predictors of New-Onset Atrial Tachyarrhythmias After Transcatheter Atrial Septal Defect Closure in Adults

BACKGROUND

New-onset atrial tachyarrhythmia (ATA) often develops after atrial septal defect (ASD) closure. Its development raises some potential concerns such as stroke and bleeding complications caused by anticoagulant therapy and limited access to the left atrium for catheter ablation. Although it is essential to identify the risk factors of new-onset ATA, few studies have examined these factors. This study investigated unknown risk factors for the development of new-onset ATA after transcatheter ASD closure in patients without a history of ATA.

METHODS

A total of 238 patients without a history of ATA, aged ≥18 years and who underwent transcatheter ASD closure at the current hospital were reviewed. Patient characteristics were compared between the groups with and without new-onset ATA. The factors associated with new-onset ATA were examined using univariate and multivariable analyses.

RESULTS

Thirteen (13) (5.5%) patients experienced ATA during follow-up (mean, 21±14 months). Compared with patients without new-onset ATA, patients with new-onset ATA were older (48±18 vs 66±11 years; p<0.001) and had high brain natriuretic peptide (BNP) levels (36±36 vs 177±306 pg/mL; p<0.001). On multivariable analysis, BNP ≥40 pg/mL before ASD closure was associated with new-onset ATA after adjusting for age (OR, 4.91; 95% CI, 1.22-19.8; p=0.025).

CONCLUSION

Patients with BNP levels >40 pg/mL before transcatheter ASD closure may have a higher risk of developing new-onset ATA.

Presence of Atrial Fibrillation in Stroke Patients With Patent Foramen Ovale: Systematic Review and Meta-Analysis

Purpose: Patent foramen ovale (PFO) is associated with ischemic stroke, especially in patients with embolic stroke of undetermined source. This study aims to evaluate the presence of atrial fibrillation (AF) in ischemic stroke patients with PFO. Methods: We systematically searched EMBASE and MEDLINE databases on May 21, 2020 for studies that analyzed the presence of AF in patients with PFO. The primary outcome was the presence of AF in patients with PFO compared with those without. Outcomes were pooled using a random-effects model using the method of DerSimonian and Laird. We recorded demographic characteristics and the methods used for AF detection in the studies included (unspecified, history/medical records review, ECG, Holter monitor, or loop recorder). Results: A total of 14 studies and 13,245 patients fulfilled the entry criteria. The average age was 61.2 years and 41.3% of the participants were female. There was a lower risk of AF in patients with PFO compared with those without (RR 0.52, 95% confidence interval, 0.41-0.63, p < 0.001). There was no evidence of heterogeneity. The lower risk of AF was found in cross-sectional and longitudinal studies and in studies stratified by average age (<60 or ≥60) and in cryptogenic stroke. Meta-regression by PFO detection technique suggested that studies using transoesophageal echocardiogram for PFO detection reported higher risk of AF (1.39, 95% confidence interval 1.14-1.70, p = 0.004). Conclusion: The presence of a PFO in patients with ischemic stroke/TIA may be associated with a lower risk of AF. Few studies have estimated the risk of future AF in patients with PFO.

Therapy of supraventricular and ventricular arrhythmias in adults with congenital heart disease-narrative review

Arrhythmias are among the most common late complications in adults with congenital heart disease (ACHD) and a frequent reason for hospital admission. Both, supraventricular and ventricular arrhythmias, not only cause debilitating symptoms, but may be life-threatening by increasing risk of stroke, causing or worsening heart failure and being associated with sudden death. Substrate and risk for arrhythmia differs widely between congenital defects with specific arrhythmias being much more common in some patients than others. Atrial macroreentrant arrhythmias are particularly frequent in patients with atrial septal defects and repair that involves atrial incisions including patients with transposition of the great arteries (TGA) and atrial switch. Accessory pathways and related arrhythmias are often associated with Ebstein's anomaly and congenitally corrected TGA. Monomorphic ventricular arrhythmias occur in patients with ventricular incisions, namely patients with Tetralogy of Fallot. Changes in surgical repair techniques influence arrhythmia prevalence and substrate as well as anatomical access for catheter ablation procedures. In addition, epidemiologic changes associated with improved long-term survival will further increase the prevalence of atrial fibrillation in ACHD. This article summarizes current understanding of prevalence of specific arrhythmias, underlying mechanisms, medical and interventional treatment options and their outcome in ACHD.

Atrial Fibrillation Following Patent Foramen Ovale Closure: Systematic Review and Meta-Analysis of Observational Studies and Clinical Trials

[Figure: see text].

Percutaneous secundum atrial septal defect closure for the treatment of atrial arrhythmia in the adult: A meta-analysis

BACKGROUND

Atrial arrhythmias are common in patients with atrial septal defects (ASD) but the effects of percutaneous closure on atrial arrhythmia prevalence is unclear. We investigated the effects of ASD device closure and the impact of age at time of closure on prevalent atrial arrythmia.

METHODS

Meta-analysis of studies reporting atrial arrhythmia prevalence in adult patients before and after percutaneous closure was performed. Primary outcomes were prevalence of 'all atrial arrhythmia' and atrial fibrillation alone post closure. Sub-group analysis examined the effects of closure according to age in patients; <40 years, ≥40 and ≥ 60 years. 25 studies were included.

RESULTS

Meta-analysis of all studies demonstrated no reduction in all atrial arrhythmia or atrial fibrillation prevalence post-closure (OR 0.855, 95% CI 0.672 to 1.087, P = .201 and OR 0.818, 95% CI 0.645 to 1.038, P = .099, respectively). A weak reduction in all atrial arrhythmia and atrial fibrillation was seen in patients ≥40 years (OR 0.77, 95% CI 0.616 to 0.979, P = .032 and OR 0.760, 95% CI 0.6 to 0.964, P = .024, respectively) but not ≥60 years (OR 0.822, 95% CI 0.593 to 1.141, P = .242 and OR 0.83, 95% CI 0.598 to 1.152, P = .266, respectively). No data were available in patients <40 years. This, and other limitations, prevents conclusive assessment of the effect of age on arrhythmia prevalence.

CONCLUSIONS

Overall, percutaneous ASD closure is not associated with a reduction in atrial arrhythmia prevalence in this meta-analysis. A weak benefit is seen in patients ≥40 years of age, not present in patients ≥60 years.

Mechanophysiologically active patch for closure of atrial septal defect

Closure of atrial septal defects (ASDs) can be achieved by various methods right from direct closure to patch closure using various materials viz. pericardium, Dacron and Teflon, to device closure using percutaneous techniques. Although percutaneous techniques are the most commonly practised method in developed countries, a subset of patients will require surgical closure. Various patch materials have been used for long, but all of them have some complications and risks associated with them. We report a case of novel technique of ASD closure done using a pedicled, vascularised and contractile right atrial wall flap.

The Presence of Patent Foramen Ovale in the Superior Type of Sinus Venosus Atrial Septal Defect

Background: The superior type of sinus venosus atrial septal defect (SVASD) is a rare form of the atrial septal defect (ASD) in which the upper part of the atrial septum does not exist. The presence of other cardiac anomalies such as anomalous pulmonary venous connections has been reported in this type of congenital heart disease. This study aimed to assess the presence of the patent foramen ovale (PFO) in patients with the superior type of SVASD.

Methods: This retrospective case-control study on 387 patients, consisting of 187 patients with a definite SVASD and 200 patients with problems other than the ASD, was conducted in Rajaie Cardiovascular Medical and Research Center between February 2005 and July 2014. Seven patients with inadequate data were excluded from the analysis. The presence/absence of the PFO was also evaluated in the case and control groups.

Results: The analyses were performed on 182 male and 198 female patients at a mean age of 39.07±14.41 and 51.01±15.80 years in the case and control groups, respectively. The PFO was significantly more frequent in the patients with the superior type of SVASD than in those without the condition (P<0.001). The persistence of the left superior vena cava was seen in 34 out of 180 patients with SVASD and in 1 out of 200 patients without the condition (18.9% vs 0.5%; P<0.001).

Conclusion: This study was the first to highlight the coexistence of the PFO and the superior type of SVASD. Physiological, genetic, or fetal factors may play an important role in the association between the PFO and the SVASD.

The use of an autologous right atrial free wall as a patch for closure of atrial septal defects

BACKGROUND

Various patch materials to close large atrial septal defects (ASDs) are autologous pericardium or a large of prosthetic patches which may be associated with infrequent but definite problems. We describe our experience with the use of the right atrial free wall patch over the last two decades.

METHODS AND RESULTS

Between July 1998 and December 2017, 157 patients (mean age 14.7 ± 13.9 years), underwent ASD closure using the right atrial free wall patch. Associated lesions were severe mitral regurgitation (n = 24), partial anomalous pulmonary venous drainage (n = 15), ASD closure occurring after myxoma excision (n = 12) total anomalous pulmonary venous drainage (n = 2) and tricuspid regurgitation (n = 2). Surgery was uneventful in all patients. All patients underwent serial electrocardiography and echocardiography. Follow-up in 140 of 155 survivors was 103.6 ± 0.6 months. One hundred forty of one hundred fifty-five survivors are in sinus rhythm and three have persistent atrial fibrillation. Twenty-four hours of Holter monitoring (n = 19) revealed normal sinus rhythm in all but three patients, with occasional atrial ectopics in one patient; four were lost to follow-op. Electrophysiological studies in seven consenting patients, 9 to 16 months following ASD closure showed normal atrial potentials from the site of the patch.

CONCLUSIONS

The autologous right atrial free wall is a safe patch material for ASD closure. Its advantages are that it is autologous, endothelialized, probably viable, and carries a low risk of thromboembolism. Studies with a larger number of patients with longer follow are needed to further confirm these findings.

Endovascular closure of patent foramen ovale: a critical appraisal of published trials

OBJECTIVE

The treatment of cryptogenic stroke patients with a patent foramen ovale (PFO) is controversial. A critical review of these studies is presented.

METHODS

A description of all trials comparing medical and endovascular treatment with closing devices is given. Additional pertinent studies are discussed to help construct a rational basis for treatment decisions.

RESULTS

Initial negative trials evaluating PFO closure were followed by positive studies published in 2017 and 2018. All trials evaluated young patients (up to 60 years). Methodological problems are present in all trials including their open label construction. Most positive trials developed strategies to increase the percentage of patients with interatrial septal aneurysms or hypermobility and large right-to-left shunts. Even in these positive trials, large numbers of patients need to be treated to avoid one stroke. Atrial fibrillation occurred in 2-6% and other adverse effects related to the procedure and to the devices occurred in a substantial number of patients. Incomplete occlusion of the PFO is also frequent. Anticoagulant treatment has not been adequately studied as a therapeutic option.

CONCLUSION

Young patients with cryptogenic strokes seem to benefit from endovascular closure of a PFO in the presence of a large right-to-left shunt or an associated atrial septum aneurysm. For most other patients, a highly-individualized decision must be made, taking into account the low risk of recurrence in patients with a cryptogenic stroke attributable to a PFO, the high numbers needed to treat and the risks related to the procedure.

Sinus Venosus Atrial Septal Defect: A Challenging Diagnosis

Sinus venosus atrial septal defect (SVASD) is a rare adult congenital heart disease which permits shunting of blood from the systemic to the pulmonary circulation and is commonly associated with anomalous pulmonary venous return.

We report a case of a 27-year-old man with a history of premature birth and unilateral cryptorchidism who was admitted for syncope. Electrocardiogram (ECG) demonstrated atrial fibrillation (AF)and S1Q3T3 pattern along with an incomplete right bundle branch block. Transthoracic echocardiography (TTE) suggested the presence of right ventricular pressure and volume overload and severe right ventricular and right atrial enlargement. The agitated saline study was negative suggesting no inter-atrial communication. Transesophageal echocardiography (TEE) demonstrated a superior SVASD and raised the possibility of an anomalous pulmonary venous connection. Chest computed tomography identified the right superior pulmonary vein connection to the superior vena cava.

The diagnosis of SVASD poses multiple challenges from the variety of symptoms to the selection of appropriate imaging and the complexity of surgical treatment. 

Sudden Cardiac Deaths in Adults with Congenital Heart Disease with Structural Abnormalities: A Retrospective Review of Cases in the Cook County Medical Examiner's Office

Sudden cardiac death is a significant cause of mortality in adults with congenital heart disease (CHD). The Cook County Medical Examiner's Office database was queried for cases of CHD as a cause of death in the period between July 2008 and April 2019. Twenty-two cases were identified, including 11 decedents with simple defects and 10 decedents with complex defects. All of the subjects were in apparent good health at the time of death. In the absence of other obvious causes of death, simple defects were considered cases of sudden cardiac death. Significant cardiac morphological changes were common in complex defects. While 16 cases had known, diagnosed/treated CHD, 5 cases had no diagnosis prior to autopsy. In these cases, the ability to recognize CHD (sometimes subtle) helped in determining the causes of death. Therefore, forensic pathologists must be able to properly recognize various forms of CHD and request consultations, when needed.

Arrhythmias and conduction disorders associated with atrial septal defects

Atrial septal defects (ASDs) are the most common form of congenital heart disease. There are 4 embryologic types of ASDs, and rhythm considerations vary based on type. ASDs have left-to-right shunt and primarily right-sided volume overload. This leads to electrical remodeling that may predispose patients to atrial tachyarrhythmias and conduction disorders. Risk for arrhythmias is increased with late age of ASD repair, shunt size, other factors such as pulmonary hypertension and comorbid conditions. Arrhythmia incidence is decreased after ASD closure, but remains elevated compared to general population. Medical and procedural therapy for arrhythmias should consider type and timing of ASD repair. Conduction disorders are rare. Sinus node dysfunction may be seen with late age of repair and large shunt size. Sinus venosus ASD exhibits a higher rate of sinus node dysfunction, especially with older surgical techniques. Ostium primum ASD has higher risk of spontaneous or post-operative AV block, though this is rare with current surgical techniques. Risk of AV block with surgical repair or device closure of secundum ASD is rare. Familial ASDs and other forms of congenital heart disease may be seen with mutations in associated myocardial transcription factors NKX2.5, GATA4, TBX6, along with conduction disorders such as AV block.

Closure, Anticoagulation, or Antiplatelet Therapy for Cryptogenic Stroke With Patent Foramen Ovale: Systematic Review of Randomized Trials, Sequential Meta-Analysis, and New Insights From the CLOSE Study

BACKGROUND

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing patent foramen ovale (PFO) closure, anticoagulation, and antiplatelet therapy to prevent stroke recurrence in patients with PFO-associated cryptogenic stroke.

METHODS AND RESULTS

We searched Medline, Cochrane Library, and EMBASE through March 2018. The primary outcome was stroke recurrence. Pooled incidences, hazard ratios, and risk ratios (RRs) were calculated in random-effects meta-analyses. PFO closure was associated with a lower risk of recurrent stroke compared with antithrombotic therapy (antiplatelet therapy or anticoagulation: 3560 patients from 6 RCTs; RR=0.36, 95% CI: 0.17-0.79; I²=59%). The effect of PFO closure on stroke recurrence was larger in patients with atrial septal aneurysm or large shunt (RR=0.27, 95% CI, 0.11-0.70; I²=42%) compared with patients without these anatomical features (RR=0.80, 95% CI, 0.43-1.47; I²=12%). Major complications occurred in 2.40% (95% CI, 1.03-4.25; I²=77%) of procedures. New-onset atrial fibrillation was more frequent in patients randomized to PFO closure versus antithrombotic therapy (RR=4.33, 95% CI, 2.37-7.89; I²=14%). One RCT compared PFO closure versus anticoagulation (353 patients; hazard ratio=0.14, 95% CI, 0.00-1.45) and 2 RCTs compared PFO closure versus antiplatelet therapy (1137 patients; hazard ratio=0.18, 95% CI, 0.05-0.63; I²=12%). Three RCTs compared anticoagulation versus antiplatelet therapy, with none showing a significant difference.

CONCLUSIONS

PFO closure is superior to antithrombotic therapy to prevent stroke recurrence after cryptogenic stroke. The annual absolute risk reduction of stroke was low, but it has to be tempered by a substantial time at risk (at least 5 years) in young and middle-aged patients. PFO closure was associated with an increased risk of atrial fibrillation.

Percutaneous closure of patent foramen ovale vs. medical treatment for patients with history of cryptogenic stroke: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Patients with history of cryptogenic stroke are more likely to have a patent foramen ovale (PFO) and should be managed with antithrombotic agents, while the alternative option is percutaneous closure of PFOs. Our aim was to perform a meta-analysis of randomized controlled trials (RCTs) comparing percutaneous closure vs. medical treatment for patients with PFO and prior cryptogenic stroke.

METHODS

Medline, Scopus and Cochrane databases were reviewed. A random-effect model meta-analysis was used and I-square was utilized to assess the heterogeneity. New ischemic stroke was defined as the primary endpoint. A sensitivity analysis was performed for Amplatzer device. Subgroup analyses were performed for different patient and PFO characteristics for the composite endpoints as defined by the included RCTs.

RESULTS

In total of 3440 patients were included in this meta-analysis. Closure devices were superior to medical therapy for prevention of recurrent ischemic strokes (HR = 0.29; CI: 0.02-0.56), but were associated with increased risk of new onset of atrial fibrillation (AF) and atrial flutter (RR = 4.67; CI: 2.22-9.81). However, in the sensitivity analysis for Amplatzer device, there was no difference between the two groups in new onset of atrial arrhythmias. Closure devices were superior across all different subgroups when compared to medical treatment with the exception of patients with a small shunt.

CONCLUSION

This meta-analysis shows that closure devices for patients with PFO and history of cryptogenic stroke can significantly decrease the risk of a new ischemic stroke. The use of Amplatzer device was not associated with increased risk of newly diagnosed atrial arrhythmias.

Arrhythmias in Patients with Atrial Defects

Atrial arrhythmias are common in patients with atrial septal defects. A myriad of factors are responsible for these that include remodeling related to the defect and scar created by the repair or closure. An understanding of potential arrhythmias, along with entrainment and high-density activation mapping can result in accurate diagnosis and successful ablation. Atrial fibrillation is being seen increasingly after patent foramen ovale closure and may be the primary etiology of recurrent stroke in these patients.

Electrocardiographic RR and QT Interval Variability in Patients with Atrial Septal Defect and Healthy Children

Atrial septal defect is a common congenital heart disease. In patients with atrial septal defect, left-to-right shunting increases the right atrial and right ventricular preload. This pathological change affects sinus node automaticity and myocardial depolarization and repolarization, and has the potential to evoke arrhythmogenic substrates. We examined the effect of atrial septal defect on sinus node automaticity and myocardial repolarization by investigating the variability in the repolarization interval, namely the QT variability index (QTVI) and variability ratio (VR). This retrospective study included 38 patients (mean age, 2.2 ± 1.9 years; mean left-to-right shunt ratio, 2.1 ± 0.70) and 40 age-matched healthy control subjects evaluated from 2008 to 2015. QTVI was calculated using the ratio of the repolarization parameter variance to heart rate variance, and VR was calculated as the ratio of the standard deviation (SD) of QT intervals to the SD of RR intervals on electrocardiography. There was a significant difference in the SD of all normal RR intervals, heart rate variance, VR, and QTVI of control subjects or patients with low shunt ratio compared with patients with high shunt ratio (all P < 0.05). Linear regression analysis revealed strong positive correlations between the left-to-right shunt ratio and VR (r = 0.662, P < 0.0001) or QTVI (r = 0.808, P < 0.0001). These repolarization indices provide information on alteration of sinus node autonomic control and the pathophysiology of myocardial repolarization, and could be used as a noninvasive indicator of the shunt ratio in children with atrial septal defect.

Management of supraventricular arrhythmias in adults with congenital heart disease

Supraventricular arrhythmias are a frequent complication in adults with congenital heart disease (ACHD). The prevalence increases with time since surgery, complexity of the underlying defect, type of repair and older age at surgery. Arrhythmias are the most frequent reason for hospital admission and along with heart failure the leading cause of death. The arrhythmia-associated increase in morbidity and mortality makes their management a key task in patients with ACHD. Intra-atrial re-entry is the most frequent arrhythmia mechanism. Less common arrhythmia mechanisms are supraventricular tachycardias in the presence of an accessory pathway, atrioventricular nodal re-entrant tachycardia or focal tachycardias. Patient management includes stroke prevention, acute termination and prevention of arrhythmia recurrence. Acute treatment depends on patients' symptoms. In cases of haemodynamic instability, immediate cardioversion is warranted. For stable patients, acute treatment includes rate control and termination by antiarrhythmic drugs or electrical cardioversion. Following a symptomatic arrhythmia, catheter ablation or treatment with antiarrhythmic drugs is recommended to prevent recurrences. Advances in mapping and ablation technology are now associated with high success rates of catheter ablation. In patients with a complex substrate recurrence rates of 50% remain high. However, in the presence of side effects and complications associated with long-term antiarrhythmic drug therapy, redo procedures are encouraged by current guidelines.