The Challenging Face of Focal Atrial Tachycardia in the Post AF Ablation Era

Which patients recur as atrial tachycardia rather than atrial fibrillation after catheter ablation of atrial fibrillation?

INTRODUCTION

The ablation gaps have been known as the main mechanism of recurrence as atrial tachycardia (AT) rather than atrial fibrillation (AF) after AF catheter ablation. However, AF organization due to reduction of critical mass or focal trigger may also be the mechanism of AT recurrence. We sought to find out the main clinical factors of recurrence as AT rather than AF after AF ablation in the absence of antiarrhythmic drug effect.

METHODS

We analyzed 521 patients (70.8% men, 64.1% paroxysmal AF) who experienced AT or AF recurrence without antiarrhythmic drug effect during 44.7 ± 25.4 months follow-up.

RESULTS

Among 521 patients with recurrence, 42.0% (219 of 521) recurred with AT. The proportion of AT recurrence was not different between the pulmonary vein isolation only group and additional linear ablation group (45.1% vs. 38.1%, p = 0.128). The absence of hypertension (odds ratio [OR] 0.49, 95% confidence interval [CI] 0.29-0.83, p = 0.007), small left atrial (LA) volume index (OR 0.89 per 10 mL/m2, 95% CI 0.79-1.00, p = 0.049), and high mean LA bipolar voltage (OR 2.03 per 1 mV, 95% CI 1.30-3.16, p = 0.002) were independently associated with AT recurrence, whereas additional linear ablation was not. Among 90 patients who underwent repeat ablation procedure, rates of PV reconnection (p = 0.358) and gap in prior linear ablations (p = 0.269) were not significantly different between AT recurrence group and AF recurrence group.

CONCLUSION

The degree of LA remodeling is significantly associated with recurrence as AT after AF ablation, irrespective of potential ablation gap in linear lesion.

Atriobronchial Fistula Complicated by Septic Cerebral Air Emboli After Pulmonary Vein Ablation

OBJECTIVE

To describe a case of an infected atriobronchial fistula as a late complication after pulmonary vein ablation, leading to septic air emboli and requiring urgent cardiac surgery.

DATA SOURCES

Clinical observation.

STUDY SELECTION

Case report.

DATA EXTRACTION

Relevant clinical information. PubMed was searched for relevant literature.

DATA SYNTHESIS

Given its high success and low complication rate, pulmonary vein isolation is expected to be increasingly performed worldwide. Despite its success, some of its rare complications are potentially devastating and are difficult to diagnose early. In this report, we present the case of a 32-year-old woman, who was readmitted to hospital 2 months after pulmonary vein ablation. The clinical picture resembled meningococcemia with spreading petechiae on legs and arms raising concern for Waterhouse-Friderichsen syndrome. Further echocardiographic investigation led to the discovery of massive amounts of intracardiac air which demanded urgent lung isolation and sternotomy. Intraoperatively a small infected left atrial perforation was oversewn and a fistula to the right main bronchus was closed by means of an autologous pericardial patch. One month later, still revalidating, she could be discharged home with only minor neurologic sequelae.

CONCLUSIONS

Clinicians should be aware of the dramatic complications of invasive antiarrhythmic procedures and their atypical and late presentations. Better preprocedural appreciation of cardiac wall thickness, early echocardiographic diagnosis, and swift referral for cardiac surgery might impact outcome dramatically.

Rapid Mapping of Right Atrial Tachycardia Using a New Multielectrode Basket Catheter

INTRODUCTION

The mapping of atrial tachycardia (AT) can often be challenging and time-consuming, especially in patients with ATs that develop following cardiac surgery or are concomitant with atrial fibrillation. Recently, a new multielectrode basket catheter (MBC) has become available; we hypothesized that the MBC could be utilized to diagnose AT circuits.

METHODS AND RESULTS

This study included 51 consecutive patients undergoing catheter ablation of clinically documented right-sided ATs (including 17 cases following cardiac surgery). Using a NavX system, 2 activation maps of the ATs were created, one using the new MBC (32 mm, 31 poles) and the other using a circular catheter. The time needed to complete the activation maps and the points acquired with both mapping catheters were compared. In all 64 ATs, including 34 non-cavotricuspid isthmus-dependent ATs, the AT activation maps created by both catheters were essentially identical. The number of points acquired to complete the activation maps did not differ significantly between the MBC and the circular catheter (387 [285-511] vs. 374 [269-533], P = 0.19), but the mapping time was significantly shorter using the MBC (4.0 [3.0-6.0] minutes vs. 8.0 [6.5-10.0] minutes, P < 0.0001). Inadvertent mechanical AT termination (n = 6) was observed only during mapping with the circular catheter.

CONCLUSION

In patients with right-sided ATs, the use of an MBC could save mapping time.

How To Follow Atrial Fibrillation Ablation Patients?

Catheter ablation is an established treatment option for symptomatic atrial fibrillation (AF), with circumferential pulmonary vein isolation being considered the cornerstone of the procedure. However, this is a complex intervention with potential major complications and with common arrhythmia recurrences. There is consensus among experts that all patients should be seen in follow-up regularly after AF ablation. To date there are limited data regarding the best methodology for routine clinical follow-up of this population. This review summarizes a contemporary insight into management of late complications following AF ablation, post-procedural anticoagulation and arrhythmia monitoring strategies, in order to prevent thromboembolic events, detect and treat arrhythmia recurrences, and discuss the use of upstream therapies after AF ablation.

Left septal atrial tachycardias: electrocardiographic and electrophysiologic characterization of a paraseptal focus

OBJECTIVE

The objective was to characterize the electrocardiographic and electrophysiological features of focal atrial tachycardia (FAT) originating from the left septum (LS).

BACKGROUND

FAT is recognized to occur at predefined anatomic locations rather than randomly throughout the atria. We describe the ECG and EP features of ATs originating from the LS as an important site for apparent perinodal tachycardias.

METHODS

Nine patients presenting with LS FAT from a consecutive series of 384 underwent EP/RFA for symptomatic FAT.

RESULTS

The mean age was 56 ± 12 years; 7 female with symptoms for 36 ± 28 months. P wave morphology (PWM) was negative/positive in lead V1 and across the precordial leads and negative or negative/positive in inferior leads in all patients. Tachycardia was incessant in 6 out of 9 patients with a mean tachycardia cycle length 421 ± 56 milliseconds. His A was ahead of P wave in all patients (mean -15 ± 5 milliseconds) and earlier than CS proximal (mean 4 ± 9 milliseconds). Successful acute focal ablation achieved at a mean of 31 ± 12 milliseconds ahead of P wave with no recurrences at a mean follow-up of 30 ± 28 months.

CONCLUSION

Although the left septum is an uncommon site for focal AT an awareness of this location for harboring foci is particularly important when mapping apparently right-sided septal tachycardias.