Real-time visualization of the esophagus and left atrial posterior wall by intra-left atrial echocardiography

Posterior wall thickness of the confluent inferior pulmonary veins measured by left atrial intracardiac echocardiography: implications for catheter ablation

BACKGROUND

Confluent inferior pulmonary veins (CIPV) is a rare anatomical variant. There is few evidence in the literature regarding anatomic landmarks consideration to guide radiofrequency application in avoiding complications in the esophagus in CIPV cases.

METHODS

Of 986 consecutive patients undergoing atrial fibrillation (AF) ablation from July 2020 to June 2022, seven (0.7%) had CIPV with a common trunk connecting to the LA diagnosed by 3-dimensional contrast-enhanced computed tomography. Using intracardiac echocardiography (ICE) performed from the left atrium (LA), we measured the posterior wall thickness (PWT) of the CIPV adjacent to the esophagus and compared the measurement with the LA posterior wall thickness (LAPWT) at the left inferior PV level of 25 controls without CIPV. For ablation in CIPV patients, each superior PV was individually isolated, and box isolation of CIPV without ablating the CIPV posterior wall was added (tri-circle ablation technique).

RESULTS

The CIPV PWT was 0.7 ± 0.1 mm, while non-CIPV LAPWT was 2.0 ± 0.4 mm (P < 0.001). In the CIPV group, upper and lower portions of the CIPV were both apart from the esophagus (mean distances, 6.7 ± 3.4 mm and 7.9 ± 2.7 mm, respectively). Individual superior PV isolation and box CIPV isolation resulted in complete isolation of all PVs, with no complications. All CIPV patients except one remained AF recurrence-free for 376 ± 52 days.

CONCLUSIONS

Although CIPV frequency is low, CIPV PWT is very thin and special care is needed during ablation. A "tri-circle" ablation strategy avoids ablating in the thinnest portion of the posterior wall. Further studies are warranted to assess the safety.

Predictors of pulmonary vein non-reconnection in the second procedure after ablation index-guided pulmonary vein isolation for atrial fibrillation and its impact on the outcome

INTRODUCTION

Although first-pass isolation (FPI) of the pulmonary vein (PV) has been suggested as a marker for PV isolation (PVI) durability, it has not been confirmed. Non-PV atrial fibrillation (AF) triggers were the main target in patients without PV reconnection in the second ablation procedure, but the outcome was unclear. We aimed to validate FPI as a marker of PVI durability and evaluate the outcome after the second procedure in patients without PV reconnection by comparing it to those with reconnection.

METHODS

Among the 2087 patients undergoing the first ablation index-guided radiofrequency AF ablation, 309 with atrial tachyarrhythmias (ATs) recurrence and undergoing the second procedure were studied. Clinical characteristics and outcomes were compared between the patients without PV reconnection (PV non-reconnection group, n = 142) and with reconnection (PV reconnection group, n = 167).

RESULTS

FPI in both PV sides in the first ablation procedure was significantly more frequent in the PV non-reconnection group (77.5%) than in the PV reconnection group (45.5%) (p < .001). Multivariate logistic regression analysis revealed that FPI (odds ratio, 3.71 [95% confidence interval, 2.23-6.19], p < .001) was the only predictor of PV non-reconnection. Radiofrequency applications for non-PV AF triggers were more frequently performed in the PV non-reconnection group (40.8% vs. 24.6%, respectively, p < .001). Kaplan-Meier analysis revealed that AT recurrence-free rate was significantly lower in the PV non-reconnection group (1-year recurrence-free rate, 62.7% vs. 75.4%, respectively; p = .01 by log-rank test).

CONCLUSION

FPI was the only independent predictor of PV non-reconnection. Despite aggressive ablation for non-PV triggers, AT recurrence was more frequent in patients with PV non-reconnection.

Relationship between the posterior atrial wall and the esophagus: esophageal position and temperature measurement during atrial fibrillation ablation (AWESOME-AF). A randomized controlled trial

BACKGROUND

Pulmonary vein isolation (PVI) implies unavoidable ablation lesions to the left atrial posterior wall, which is closely related to the esophagus, leading to several potential complications. This study evaluates the usefulness of the esophageal fingerprint in avoiding temperature rises during paroxysmal atrial fibrillation (PAF) ablation.

METHODS

Isodistance maps of the atrio-esophageal relationship (esophageal fingerprint) were derived from the preprocedural computerized tomography. Patients were randomized (1:1) into two groups: (1) PRINT group, the PVI line was modified according to the esophageal fingerprint; (2) CONTROL group, standard PVI with operator blinded to the fingerprint. The primary endpoint was temperature rise detected by intraluminal esophageal temperature probe monitoring. Ablation settings were as specified on the Ablate BY-LAW study protocol.

RESULTS

Sixty consecutive patients referred for paroxysmal AF ablation were randomized (42 (70%) men, mean age 60 ± 11 years). Temperature rise (> 39.1 °C) occurred in 5 (16%) patients in the PRINT group vs. 17 (56%) in the CONTROL group (p < 0.01). Three AF recurrences were documented at a mean follow-up of 12 ± 3 months (one (3%) in the PRINT group and 2 (6.6%) in the CONTROL group, p = 0.4).

CONCLUSION

The esophageal fingerprint allows for a reliable identification of the esophageal position and its use for PVI line deployment results in less frequent esophageal temperature rises when compared to the standard approach. Further studies are needed to evaluate the impact of PVI line modification to avoid esophageal heating on long-term outcomes. The development of new imaging-derived tools could ultimately improve patient safety (NCT04394923).