Outcome of cryoballoon ablation for atrial fibrillation: Medium-term follow-up from a single center

Left atrial appendage closure after cryoballoon ablation in patients with atrial fibrillation

BACKGROUND

Cryoballoon ablation (CBA) is effective for patients with drug-refractory symptomatic atrial fibrillation (AF). For patients with a high risk of stroke (CHA₂DS₂-VASc score ≥2), life-long oral anticoagulation therapy should be continued even after successful catheter ablation. We investigated the safety and efficacy of concomitant use of a second-generation CBA catheter for pulmonary vein isolation (PVI) and a left atrial appendage closure (LAAC) device in patients with AF.

METHODS

We enrolled 27 patients (64.7 ± 6.3 years, 74% male, 63% paroxysmal AF, 37% persistent AF, 4.8 ± 1.4 CHA₂DS₂-VASc score, and 3.6 ± 1.3 HAS-BLED score). In total, 85% of the patients had a prior stroke or TIA, and 30% of patients had a clinical history of bleeding. Patients received a CBA for PVI and underwent occlusion of the LAA with an LAAC device. The efficacy of CBA was defined as lack of arrhythmia recurrence (AF, atrial flutter, and/or atrial tachycardia lasting ≥30 s) after a 90-day blanking period. The success of LAAC was determined by the rate of stroke, TIA, and/or bleeding events.

RESULTS

The mean procedural time for CBA and LAAC was 80 ± 16 min and 44 ± 12 min, respectively. Acute PVI by CBA was achieved in 100% of the procedures, and 96% of patients obtained acute LAAC device placement during the procedure. Upon complete release of the LAAC device, only 62% patients (16/26) had no detectable leakage during intraprocedural transesophageal echocardiography. Three patients experienced an acute complication: a pericardial effusion and two phrenic nerve palsy events. Mean follow-up was 18 months (range 9-23 months), and freedom from AF recurrence was 74% (20/27).

CONCLUSION

The intraprocedural combination of CBA and LAAC is feasible in patients with non-valvular AF with a high risk of stroke, TIA, and/or bleeding. Larger long-term randomized studies are needed to judge the overall safety and efficacy of the combined procedure.

Left atrial structure and function predictors of recurrent fibrillation after catheter ablation: a systematic review and meta-analysis

BACKGROUND

Catheter ablation (CA) has become a conventional treatment for atrial fibrillation (AF), but remains with high recurrence rate. The aim of this meta-analysis was to determine left atrial (LA) structure and function indices that predict recurrence of AF.

METHODS

We systematically searched PubMed-Medline, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry, up to September 2017 in order to select clinical trials and observational studies which reported echocardiographic predictors of AF recurrence after CA. Eighty-five articles with a total of 16 126 patients were finally included.

RESULTS

The pooled analysis showed that after a follow-up period of 21 ± 12 months, patients with AF recurrence had larger LA diameter with weighted mean difference (WMD: 2·99 ([95% CI 2·50-3·47], P<0·001), larger LA volume index (LAVI) maximal and LAVI minimal (P<0·0001 for both), larger LA area (P<0·0001), lower LA strain (P<0·0001) and lower LA total emptying fraction (LA EF) (P<0·0001) compared with those without AF recurrence. The most powerful LA predictors (in accuracy order) of AF recurrence were as follows: LA strain <19% (OR: 3·1[95% CI, -1.3-10·4], P<0·0001), followed by LA diameter ≥50 mm (OR: 2·75, [95% CI 1·66-4·56,] P<0·0001), and LAVmax >150 ml (OR: 2·25, [95% CI, 1.1-5·6], P = 0·0002).

CONCLUSIONS

Based on this meta-analysis results, a dilated left atrium with diameter more than 50 mm and volume above 150 ml or myocardial strain below 19% reflect an unstable LA that is unlikely to hold sinus rhythm after catheter ablation for atrial fibrillation.

Early recurrence of atrial tachyarrhythmia during the 90-day blanking period after cryoballoon ablation in patients with atrial fibrillation: The characteristics and predictive value of early recurrence on long-term outcomes

OBJECTIVE

To investigate the characteristics of early recurrence (ER) of atrial tachyarrhythmia (ATA) defined as atrial fibrillation (AF), atrial tachycardia (AT), or atrial flutter (AFL) during a 90-day blanking period after pulmonary vein isolation by cryoablation (PVI-C) in patients with symptomatic drug refractory AF. Specifically, to determine if ER of ATA during the blanking period can predict late recurrence (LR) during a 12-month follow-up period.

METHOD

A total of 51 patients with symptomatic AF (who received PVI-C) were monitored by trans-telephonic wireless electrocardiogram (TWECG) event recording during the landmark 90-day blanking period following an index ablation. Recurrent ATA was defined as any AF, AT, or AFL lasting longer than 30 s (as recorded by 12‑lead ECG, 24-hour Holter monitor, or TWECG). For data analysis, patients were grouped into ER and non-ER cohorts during the 90-day blanking period and then cohorted into LR or non-LR groups during the 12-month follow-up.

RESULTS

During the 90-day blanking period, 23 patients had an ER event of ATA while 28 patients had a non-ER experience. Also, during the 12-month follow-up period, 15 patients had a LR event while 36 patients were free from ATA (and placed in the non-LR cohort). Overall, the average success rate of cryoablation for AF was 70.6% at the 12-month follow-up period. Compared to the non-LR group, patients with LR showed a higher average percentage of diabetes mellitic (33.3% vs. 5.56%; P = 0.008) and had a larger mean left atrium diameter (41.2 ± 4.3 mm vs. 36.5 ± 4.2 mm; P = 0.0006). During evaluation of the 90-day blanking period, the LR group had more frequent attacks of ATA than compared to the non-LR group (27.7% vs. 2.4%; P < 0.001). Only two patients (7.1%) without ER in the blanking period (non-ER cohort) had relapsed into a LR of ATA during the one-year period. After multi-logistic regression analysis, ER could individually predict the risk of LR (RR = 58.8; P = 0.001).

CONCLUSION

In our study, ER of ATA was a common phenomenon during the 90-day blanking period after PVI-C for AF, and it mostly occurred in the first month following the index ablation across all patients. ER is not equal to the LR of ATA; however, patients with an ER event had a higher risk of a LR during the 12-month follow-up period.

Clinical scores for outcomes of rhythm control or arrhythmia progression in patients with atrial fibrillation: a systematic review

Patients with atrial fibrillation (AF) are commonly managed with rhythm control strategy, but the natural history of this common arrhythmia leads itself to progression from paroxysmal to persistent or permanent AF, and recurrences are evident despite rhythm control treatments using cardioversion or catheter ablation. Numerous clinical factors have been associated with outcomes of rhythm control or arrhythmia progression in patients with AF. The more common factors have been used to formulate risk stratification scores, to help predict the outcomes of rhythm control treatments or AF progression. This review article provides an overview on the published clinical risk scores related to outcomes of rhythm control strategy or AF progression.