Atrial Tachycardias After Atrial Fibrillation Ablation: How to Manage?

Catheter Ablation of Atrial Tachycardia after Pulmonary Vein Isolation in a Patient with Common Ostium of Inferior Pulmonary Veins: Case Report

Background and Objectives: Atrial fibrillation (AF), a prevalent cardiac arrhythmia, significantly impacts the quality of life of those affected. The preferred treatment for symptomatic AF, particularly when pharmacological methods fall short, is catheter ablation with pulmonary vein isolation (PVI). While common pulmonary vein (PV) anatomical variants, such as the right accessory pulmonary vein and the common ostium of left pulmonary veins (LCPV), have been studied extensively, their impact on the long-term outcome of PVI is known to be minimal. However, data on less common anomalies, like the common ostium of the left and right inferior pulmonary vein (CIPV), remain scarce in the medical literature. This report aims to shed light on the challenges and outcomes of catheter ablation in a patient with a rare CIPV anomaly. By presenting this case, we contribute to the limited knowledge about the management of such unique anatomical variations in AF treatment and discuss the importance of individualized treatment approaches. Case Presentation: We present a case involving a 56-year-old male diagnosed with AF in 2018. Initial PVI treatment was successful, but the patient experienced symptom recurrence after three years. A preprocedural CT scan before the second ablation revealed a CIPV anomaly. During the repeat procedure, a right superior pulmonary vein (RSPV) reisolation was performed due to identified gaps in the previous ablation line. Post-procedure, the patient maintained a sinus rhythm and reported no further symptoms. Conclusions: This case highlights the importance of recognizing rare PV anatomies like CIPV in the effective management of AF. Tailored ablation strategies, accounting for unique anatomical conditions, can lead to successful long-term outcomes, reinforcing the need for personalized approaches in AF treatment, especially in cases involving complex anatomical variations.

Pre-Procedural Right Atrial Diameter May Predict the Development of Typical Atrial Flutter in Patients Undergoing Catheter Ablation for Atrial Fibrillation

BACKGROUND

Some patients undergoing catheter ablation for atrial fibrillation may develop typical atrial flutter on follow-up, and a second procedure for typical atrial flutter is often required in such patients. In this study, we aimed to define the variables associated with the development of typical atrial flutter after ablation.

METHODS

One hundred fifty-nine patients who underwent catheter ablation for the first time due to atrial fibrillation and who did not have a previously documented atrial flutter were included in the study. Before ablation, baseline clinical features and echocardiographic parameters were recorded. At the 1st, 3rd, 6th, and 12th months after the procedure, and then annually, the patients were followed up for typical atrial flutter development.

RESULTS

At a mean follow-up of 34.0 (14.0-50.0) months, typical atrial flutter developed in 21 (13.2%) patients. During the follow-up, right atrial diameter was greater in those who developed typical atrial flutter than those who did not [39.0 (38.0-43.0) vs. 36.0 (34.0-39.0) mm, P <.001]. A multiple Cox regression analysis showed that the right atrial diameter was the only independent predictor of typical atrial flutter development (hazard ratio = 1.12, 95% CI: 1.02-1.23, P =.021). A receiver operating characteristic analysis showed that the best cutoff for the right atrial diameter was 38.5 mm to predict typical atrial flutter development (area under the curve = 0.77, 95% CI: 0.67-0.86, sensitivity = 62%, specificity = 75%, P <.001).

CONCLUSION

In patients undergoing catheter ablation for atrial fibrillation, a pre-procedural right atrial diameter measurement may predict typical atrial flutter development at follow-up. In particular, patients with a pre-procedural right atrial diameter ≥39 mm may be at a higher risk for developing typical atrial flutter in the future.

Treatment of pathophysiologic propagation outside of the pulmonary veins in retreatment of atrial fibrillation patients: RECOVER AF study

AIMS

RECOVER AF evaluated the performance of whole-chamber non-contact charge-density mapping to guide the ablation of non-pulmonary vein (PV) targets in persistent atrial fibrillation (AF) patients following either a first or second failed procedure.

METHODS AND RESULTS

RECOVER AF was a prospective, non-randomized trial that enrolled patients scheduled for a first or second ablation retreatment for recurrent AF. The PVs were assessed and re-isolated if necessary. The AF maps were used to guide the ablation of non-PV targets through elimination of pathologic conduction patterns (PCPs). Primary endpoint was freedom from AF on or off antiarrhythmic drugs (AADs) at 12 months. Patients undergoing retreatment with the AcQMap System (n = 103) were 76% AF-free at 12 months [67% after single procedure (SP)] on or off AADs (80% free from AF on AADs). Patients who had only received a pulmonary vein isolation (PVI) prior to study treatment of non-PV targets with the AcQMap System were 91% AF-free at 12 months (83% SP). No major adverse events were reported.

CONCLUSION

Non-contact mapping can be used to target and guide the ablation of PCPs beyond the PVs in persistent AF patients returning for a first or second retreatment with 76% freedom from AF at 12 months. The AF freedom was particularly high, 91% (43/47), for patients enrolled having only a prior de novo PVI, and freedom from all atrial arrhythmias for this cohort was 74% (35/47). These early results are encouraging and suggest that guiding individualized targeted ablation of PCPs may therefore be advantageous to target at the earliest opportunity in patients with persistent AF.

Network meta-analysis and systematic review comparing efficacy and safety between very high power short duration, high power short duration, and conventional radiofrequency ablation of atrial fibrillation

BACKGROUND

High-power short-duration (HPSD) atrial fibrillation (AF) ablation with a power of 40-50 W was proved to be safe and effective. Very high-power short-duration (vHPSD) AF ablation is a novel method using >50 W to obtain more durable AF ablation. This study aimed to evaluate the efficacy and safety of vHPSD ablation compared with HPSD ablation and conventional power ablation.

METHODS

A literature search for studies that reported AF ablation outcomes, including short-term freedom from atrial arrhythmia, first-pass isolation (FPI) rate, procedure time, and major complications, was conducted utilizing MEDLINE, EMBASE, and Cochrane databases. All relevant studies were included in this analysis. A random-effects model of network meta-analysis and surface under cumulative ranking curve (SUCRA) were used to rank the treatment for all outcomes.

RESULTS

A total of 29 studies with 9721 patients were included in the analysis. According to the SUCRA analysis, HPSD ablation had the highest probability of maintaining sinus rhythm. Point estimation showed an odds ratio of 1.5 (95% confidence interval [CI]: 1.2-1.9) between HPSD ablation and conventional power ablation and an odds ratio of 1.3 (95% CI: 0.78-2.2) between vHPSD ablation and conventional power ablation. While the odds ratio of FPI between HPSD ablation and conventional power ablation was 3.6 (95% CI: 1.5-8.9), the odds ratio between vHPSD ablation and conventional power ablation was 2.2 (95% CI: 0.61-8.6). The procedure times of vHPSD and HPSD ablations were comparable and, therefore, shorter than that of conventional power ablation. Major complications were low in all techniques.

CONCLUSION

vHPSD ablation did not yield higher efficacy than HPSD ablation and conventional power ablation. With the safety concern, vHPSD ablation outcomes were comparable with those of other techniques.

Atrial tachycardia occurring after a prior atrial fibrillation ablation procedure: Does non-inducibility matter?

Recurrent atrial tachycardia (AT) is a common phenomenon after catheter ablation for AF, particularly in the setting of additional substrate ablation, with many studies demonstrating gap-related macro re-entrant AT (predominantly mitral and roof dependent) to be the dominant mechanism. Although multiple inducible ATs after ablation of the clinical AT are commonly described at repeat procedures, the optimal ablation strategy, and procedural endpoints are unclear in this setting. A recent randomized study addressing the question of non-inducibility as a procedural endpoint demonstrated no additional benefits to the ablation of all induced, non-clinical ATs, but it was limited by small numbers and high rates of non-inducibility. Nevertheless, once ablation of the clinical AT has been successfully performed, ensuring durable linear block and PV isolation may be sufficient for the prevention of further AT. Durable linear block, particularly at the mitral isthmus, is difficult to achieve but may be facilitated by the real-time evaluation of lesion quality and contiguity and the novel technique of vein of Marshall ethanol infusion. Large-scale, randomized trials are needed, nonetheless, to fully assess the optimal ablation strategy in the setting of recurrent AT post-AF ablation.

Clinical utility of non-contact charge density 'SuperMap' algorithm for the mapping and ablation of organized atrial arrhythmias

AIMS

SuperMap is a novel non-contact algorithm for the mapping of organized atrial arrhythmias. We prospectively evaluated SuperMap during mapping and ablation of atrial tachycardias (ATs) and paced rhythms and compared to conventional high-density contact mapping.

METHODS AND RESULTS

Consecutive patients undergoing SuperMap guided ablation of pre-existing ATs or AT developed during atrial fibrillation ablation procedures were included together with maps obtained during pacing to assess block in linear lesions. The time taken to obtain diagnostic maps was measured together with the number of electrogram (EGM) points and accuracy compared to the arrhythmia diagnosis confirmed using a combination of map findings, entrainment, and response to ablation. In a subgroup of patients, concurrent contact mapping was performed with contact and SuperMap analysed by separate operators blinded to the other technique. The time taken to generate a diagnostic map, EGM number, and map accuracy was compared. Thirty-one patients (62 maps) were included with contact mapping performed in 19 [39 maps (33 for AT)]. SuperMap acquisition time was 314 s [interquartile range (IQR) 239-436]. The median number of EGM points used per map was 5399 (IQR 3279-8677). SuperMap was faster than contact mapping [394 ± 219 s vs. 611 ± 331 s; difference 217 s, 95% confidence interval (CI) 116-318, P < 0.0005]. The number of EGM points used per map was higher for SuperMap (7351 ± 5054 vs. 3620 ± 3211; difference 3731, 95% CI 2073-5388, P < 0.0005). SuperMap and contact mapping were accurate in 92% and 85% of maps, respectively, P = 0.4805.

CONCLUSION

SuperMap non-contact charge density mapping is a rapid and reliable approach to guide the ablation of complex atrial arrhythmias.

The superiority of high-power short-duration radiofrequency catheter ablation strategy for atrial fibrillation treatment: A systematic review and meta-analysis study

BACKGROUND

Radiofrequency catheter ablation (RFCA) using the high-power short duration (HPSD) results in better ablation lesion formation in the swine model. This systematic review and meta-analysis purposed to investigate the safety and efficacy profile between HPSD and low-power long-duration (LPLD) ablation strategies to treat atrial fibrillation (AF) patients.

METHODS

We completed the literature review after identifying the relevant articles comparing HPSD and LPLD ablation methods for AF recorded in ClinicalTrials.com, CENTRAL, PubMed, and ScienceDirect until February 2021. The overall effects were calculated using pooled risk ratio (RR) and mean difference (MD) for categorical and continuous data, respectively. We also estimated the 95% confidence interval (CI).

RESULTS

The HPSD strategy took shorter procedure time (MD = -33.75 min; 95% CI = -44.54 to -22.97; P < .01), fluoroscopy time (MD = -5.73 min; 95% CI = -8.77 to -2.70; P < .001), and ablation time (MD = -17.71; 95% CI = -21.02 to -14.41) than LPLD strategy. The HPSD RFCA was correlated with lower risk of esophageal thermal injury (RR = 0.75; 95% CI = 0.59 to 0.94; P = .02). The HPSD method resulted in higher first-pass pulmonary vein isolation (PVI) (RR = 1.36; 95% CI = 1.13 to 1.64; P < .01), lower PV reconnection (RR = 0.47; 95% CI = 0.34 to 0.64; P < .01), and lower recurrent AF (RR = 0.72; 95% CI = 0.54 to 0.96; P = .02) than LPLD strategy.

CONCLUSION

HPSD RFCA was superior to the conventional LPLD RFCA in terms of safety and efficacy in treating AF patients.