Progression of late postoperative atrial fibrillation in patients with tetralogy of Fallot

Severe hypoxemia after radiofrequency ablation for atrial fibrillation in palliatively repaired tetralogy of Fallot: A case report

BACKGROUND

Patients with tetralogy of Fallot (TOF) often have arrhythmias, commonly being atrial fibrillation (AF). Radiofrequency ablation is an effective treatment for AF and does not usually cause severe postoperative hypoxemia, but the risk of complications may increase in patients with conditions such as TOF.

CASE SUMMARY

We report a young male patient with a history of TOF repair who developed severe hypoxemia after radiofrequency ablation for AF and was ultimately confirmed to have a new right-to-left shunt. The patient subsequently underwent atrial septal occlusion and eventually recovered.

CONCLUSION

Radiofrequency ablation may cause iatrogenic atrial septal injury; thus possible complications should be predicted in order to ensure successful treatment and patient safety.

Atrial Fibrillation Ablation in Congenital Heart Disease: Therapeutic Challenges and Future Perspectives

The increasing prevalence of atrial fibrillation (AF) in adults with congenital heart disease raises significant questions regarding its management. The unique underlying anatomic and physiological background further adds to the difficulty in eliminating the AF burden in these patients. Herein, we provide an overview of the current knowledge on the pathophysiology and risk factors for AF in adult congenital heart disease, with a special focus on the existing challenges in AF ablation. Emerging imaging modalities and ablation techniques might have a role to play. Evidence regarding the safety and efficacy of AF ablation in adult congenital heart disease is summarized, especially for patients with an atrial septal defect, Ebstein anomaly of the tricuspid valve, tetralogy of Fallot, and Fontan circulation. Finally, any remaining gaps in knowledge and potential areas of future research are highlighted.

Catheter ablation in adults with congenital heart disease: A 15-year perspective from a tertiary centre

BACKGROUND

With the growing adult congenital heart disease (ACHD) population, the number of catheter ablation procedures is expected to dramatically increase. Data reporting experience and evolution of catheter ablation in patients with ACHD, over a significant period of time, remain scarce.

AIM

We aimed to describe temporal trends in volume and outcomes of catheter ablation in patients with ACHD.

METHODS

This was a retrospective observational study including all consecutive patients with ACHD undergoing attempted catheter ablation in a large tertiary referral centre over a 15-year period. Acute procedural success rate and freedom from recurrence at 12 and 24 months were analysed.

RESULTS

From November 2004 to November 2019, 302 catheter ablations were performed in 221 patients with ACHD (mean age 43.6±15.0 years; 58.9% male sex). The annual number of catheter ablations increased progressively from four to 60 cases per year (P<0.001). Intra-atrial reentrant tachycardia/focal atrial tachycardia was the most common arrhythmia (n=217, 71.9%). Over the study period, acute procedural success rate increased from 45.0% to 93.4% (P<0.001). Use of irrigated catheters (odds ratio [OR] 4.03, 95% confidence interval [CI] 1.86-8.55), a three-dimensional mapping system (OR 3.70, 95% CI 1.72-7.74), contact force catheters (OR 3.60, 95% CI 1.81-7.38) and high-density mapping (OR 3.69, 95% CI 1.82-8.14) were associated with acute procedural success. The rate of freedom from any recurrence at 12 months increased from 29.4% to 66.2% (P=0.001). Seven (2.3%) non-fatal complications occurred.

CONCLUSIONS

The number of catheter ablation procedures in patients with ACHD has increased considerably over the past 15 years. Growing experience and advances in ablative technologies appear to be associated with a significant improvement in acute and mid-term outcomes.

Outcomes of Atrial Arrhythmia Surgery in Patients With Congenital Heart Disease: A Systematic Review

Background The improved life expectancy of patients with congenital heart disease is often accompanied by the development of atrial tachyarrhythmias. Similarly, the number of patients requiring redo operations is expected to continue to rise as these patients are aging. Consequently, the role of arrhythmia surgery in the treatment of atrial arrhythmias is likely to become more important in this population. Although atrial arrhythmia surgery is a well-established part of Fontan conversion procedures, evidence-based recommendations for arrhythmia surgery for macroreentrant atrial tachycardia and atrial fibrillation in other patients with congenital heart disease are still lacking. Methods and Results Twenty-eight studies were included in this systematic review. The median reported arrhythmia recurrence was 13% (interquartile range, 4%-26%) during follow-up ranging from 3 months to 15.2 years. A large variation in surgical techniques was observed. Based on the acquired data, biatrial lesions are more effective in the treatment of atrial fibrillation than exclusive right-sided lesions. Right-sided lesions may be more appropriate in the treatment of macroreentrant atrial tachycardia; evidence for the superiority of additional left-sided lesions is lacking. There are not enough data to support the use of exclusive left-sided lesions. Theoretically, prophylactic atrial arrhythmia surgery may be beneficial in this population, but evidence is currently limited. Conclusions To be able to provide recommendations for arrhythmia surgery in patients with congenital heart disease, future studies should report outcomes according to the type of preoperative arrhythmia, underlying congenital heart disease, lesion set, and energy source. This is essential for determining which surgical techniques should ideally be applied under which circumstances.

Impact of atrial arrhythmia on survival in adults with tetralogy of Fallot

BACKGROUND

Atrial arrhythmia is a late complication after tetralogy of Fallot (TOF) repair, but arrhythmia outcomes data are limited.

OBJECTIVES

The purpose of the study was to describe atrial arrhythmia presentations, outcomes of antiarrhythmic therapy, and impact of arrhythmia on transplant-free survival.

METHODS

We reviewed the MACHD (Mayo Adult Congenital Heart Disease) Registry and identified 113 patients (age 49 ± 13 years) with documented arrhythmia, and 302 patients without history of arrhythmia, 1990-2017. We classified arrhythmias into atrial fibrillation and atrial flutter/tachycardia based on the rhythm on the first abnormal electrocardiogram.

RESULTS

At the time of first documented arrhythmia, 58(51%) had atrial fibrillation while 55(49%) had atrial flutter/tachycardia. Of the 113 patients, 14(12%) received rhythm control with class I/III antiarrhythmic drugs (AAD), 79(70%) had direct current cardioversion, 9(8%) received rate control with class II/IV AAD, and 11(10%) received only anticoagulation. Successful cardioversion occurred in 100(89%) patients, and arrhythmia recurrence rate was 16 per 100 patient-years. The multivariate risk factors for death and/or heart transplant were atrial fibrillation (HR 1.94, CI 1.10-3.15, P = .031) and older age (HR 1.63, CI 1.12-2.43, P = .019) per 5 year increment.

CONCLUSIONS

Atrial fibrillation, but not atrial flutter, was associated with reduced survival in our repaired TOF cohort. Further studies are required to determine if more aggressive antiarrhythmic therapy will improve survival in patients with atrial fibrillation.