Second versus fourth generation of cryoballoon catheters: The 1STOP real-world multicenter experience.

BACKGROUND: It has been observed that the fourth-generation cryoballoon (CB4) ablation catheter increased the rate of acute real-time recordings of pulmonary vein isolation (PVI) during the ablation for the treatment of atrial fibrillation (AF). The aim of this analysis was to compare the long-term outcome results between patients treated with the CB4 and second-generation cryoballoon (CB2). METHODS: In total, 492 patients suffering from AF, underwent PVI ablation with either the CB2 or CB4 catheter within this examination of the 1STOP real-world Italian project and were included in the analysis. Specifically, 246 consecutive patients treated by CB4 were compared to 246 propensity-matched control patients who underwent PVI using CB2. RESULTS: When comparing the patient cohorts treated with CB2 versus CB4, acute success rate (99.6 ± 4.7% vs. 99.7 ± 3.6%, p = .949) and peri-procedural complications (3.7% vs.1.2%, p = .080) were similar in both groups, respectively. However, procedure time (100 vs.75 min, p < .001) and fluoroscopy duration (21 vs.17 min, p < .001) were all significantly lower in the CB4 treated patient cohort. At the 12-month follow-up, the freedom from AF recurrence after a 90-day blanking period was significant higher in the CB4 as compared with the CB2 group (93.3% vs.81.3%, p < .001). CONCLUSIONS: In summary, usage of the CB4 ablation catheter increased the rate of acute PVI recording capability and resulted in a higher rate of long-term PVI success, as demonstrated by the reduced rate of AF recurrence in comparison to the CB2 cohort at the 12-month follow-up period.

A comparison of acute procedural outcomes within four generations of cryoballoon catheters utilized in the real-world multicenter experience of 1STOP.

INTRODUCTION: Four generations of the cryoballoon (CB) catheter were retrospectively evaluated in a real-world examination of patients with atrial fibrillation (AF). METHODS AND RESULTS: Four hundred eighty patients (27% female and 60 ± 10 years) suffering from AF, underwent pulmonary vein (PV) ablation with one-of-four generations of the CB catheter. The total cohort was divided into four groups of patients: 120 with first-generation (CB-1); 120 with second-generation (CB-2); 120 with third-generation (CB-3); and 120 with fourth-generation (CB-4). Equal group sizes were achieved by examining the last 120 patients treated in each cohort, attempting to minimize the effect of a learning curve between the generations of CB catheter. Baseline clinical and patient characteristics were similar between the four cohorts, excepting age and the number of tested antiarrhythmic drugs. Procedure, fluoroscopy, and left atrial dwell times were significantly lower in the CB-4 cohort compared to previous generations of the CB catheters, while the acute procedural success rate was comparable across all catheter groups (>99%). Total acute procedural complications were low (2.5%), and acute complications were comparable within the CB-2, CB-3, and CB-4 groups (0.8% reported in each cohort). The rate of time-to-isolation (TTI) visualization increased with later generations of the CB catheters. CONCLUSIONS: The novel CB-4 achieved significantly faster procedural ablation times in comparison to the previous generations, while still maintaining a low rate of acute complications. Also, the rate of TTI visualization was observed to be higher with the CB-4 catheter. Further long-term evaluation is necessary, including an assessment of AF recurrence and PV reconnection(s).

Cryoballoon or radiofrequency ablation? Alternating technique for repeat procedures in patients with atrial fibrillation.

BACKGROUND: Which technique is better for repeat ablation in patients with atrial fibrillation (AF) remains unclear. The aim of the study was to compare long-term efficacy of repeat ablation using the alternative technique for the first redo ablation procedure: (a) cryoballoon (CB) re-ablation after a failed index pulmonary vein isolation (PVI) with radiofrequency (RF) ablation, RF-then-CB group or (b) RF repeat ablation following a failed CB ablation, CB-then-RF group. METHODS: Within the 1STOP Italian Project, consecutive patients undergoing repeat ablation with a different technique from the index procedure were included. RESULTS: We studied 474 patients, 349 in RF-then-CB and 125 in CB-then-RF group. Less women (21% vs 30%; P = .041), more persistent AF (33% vs 22%; P = .015), longer duration of AF (60 vs 31 months; P < .001), and more hypertension (50% vs 36%; P = .007) were observed in the RF-then-CB cohort as compared with the CB-then-RF group. The number of reconnected PVs was 3.7 ± 0.7 and 1.4 + 1.3 in RF-then-CB and CB-then-RF group, respectively (P < .001). During the follow-up, significantly less AF recurrence occurred in the CB-then-RF group (22% vs 8%, HR = 0.46; 95% CI: 0.24-0.92; P = .025). Cohort designation was the only independent predictor of AF recurrence. CONCLUSION: Alternation of energy source for repeat ablation was safe and effective, regardless the energy used first. However, patients initially treated with CB PVI undergoing repeat ablation with RF current had less AF recurrence at long-term follow-up as compared with those originally treated by RF ablation receiving a CB repeat ablation.

Timing of cryoballoon pulmonary vein isolation to prevent atrial fibrillation recurrence.

BACKGROUND: The aims of this analysis were: to evaluate the impact of timing of ablation on the rate of atrial arrhythmias recurrence, verify if the timing of ablation impact differently in patients with paroxysmal and persistent AF. METHODS: Three thousand two hundred and five patients (60.5 ± 10 years, female 28.4%%, 78.8%% paroxysmal AF) were included in the analysis. All patients underwent only cryoballoon (CB) pulmonary vein (PV) isolation during the index procedure. RESULTS: The mean procedure time was 102.8 ± 50 min, with a mean fluoroscopy time of 26.3 ± 49 min. Acute PV isolation was achieved in 11760/11793 (99.7%) PVs. A total of 91 (2.8%) patients experienced a procedure-related complication. During the observation period 913/3205 (28.5%) patients had at least one atrial arrhythmias episode: 28% of patients with paroxysmal AF vs 33% of patients with persistent AF. In multivariate analysis, persistent AF together with time from symptomatic AF diagnosis to ablation, female sex, and ablation time showed to be significant predictors for AF recurrence. In particular, months from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence (HR = 1.23, 95% CI = 1.03-1.46, p = 0.020). In patients with paroxysmal AF, the multivariate analysis confirmed that months from first symptomatic AF episode > 18 month was an independent predictor of AF recurrence together with age > 62 years and female sex. In patients with persistent AF, the time from persistent AF showed to be significant predictor for AF recurrence. CONCLUSIONS: In this multicenter analysis, time from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence after CB PV isolation.

Role of CHA2DS2-VASc score in predicting atrial fibrillation recurrence in patients undergoing pulmonary vein isolation with cryoballoon ablation.

BACKGROUND: Pulmonary vein isolation by cryoablation (PVI-C) is a standard therapy for the treatment of atrial fibrillation (AF). The CHA2DS2-VASc score is a well-established predictor of AF-related stroke. Whether the CHA2DS2-VASc score can also be useful in predicting the long-term clinical outcomes following PVI-C is still unsettled. The aim of this analysis was to evaluate the role of the CHA2DS2-VASc score in predicting AF recurrence after PVI-C. METHODS: Patients with symptomatic AF underwent an index PVI-C. Data were collected prospectively in the framework of the 1STOP ClinicalService project. Patients were categorized into two groups: low risk (LR) and high risk (HR) based on CHA2DS2-VASc score (0-1 and ≥ 2, respectively). RESULTS: Out of 3313 patients, 1910 (57.6%) had a CHA2DS2-VASc score between 0 and 1, while 1403 (42.3%) had CHA2DS2-VASc > = 2. Patient characteristics were significantly different between the two cohorts, including age, sex, BMI, paroxysmal AF, history of stroke, diabetes, and ischemic cardiomyopathy. On the contrary, procedural times and acute complications were comparable. The 36-month freedom from AF after a single procedure was 72.5% (95% CI: 69.8-75.0) in the LR group and 65.9% (95% CI: 62.3-69.2) in the HR score group (HR: 1.26, 95% CI: 1.08-1.47, p = 0.001). After multivariate analysis, higher CHA2DS2-VASc score was still a significant predictor of the risk of AF recurrence (HR: 1.33; 1.10-1.60, p = 0.003). CONCLUSIONS: PVI-C is highly effective in the treatment of AF over the long term. A CHA2DS2-VASc score ≥ 2 is an independent predictor of AF recurrence during the follow-up and should be considered during the clinical management after the index procedure.

Factors affecting signal quality in implantable cardiac monitors with long sensing vector.

PURPOSE: Electrical artefacts are frequent in implantable cardiac monitors (ICMs). We analyzed the subcutaneous electrogram (sECG) provided by an ICM with a long sensing vector and factors potentially affecting its quality. METHODS: Consecutive ICM recipients underwent a follow-up where demographics, body mass index (BMI), implant location, and surface ECG were collected. The sECG was then analyzed in terms of R-wave amplitude and P-wave visibility. RESULTS: A total of 84 patients (43% female, median age 68 [58-76] years) were enrolled at 3 sites. ICMs were positioned with intermediate inclination (n = 44, 52%), parallel (n = 35, 43%), or perpendicular (n = 5, 6%) to the sternum. The median R-wave amplitude was 1.10 (0.72-1.48) mV with P waves readily visible in 69.2% (95% confidence interval, CI: 57.8%-79.2%), partially visible in 23.1% [95% CI: 14.3%-34.0%], and never visible in 7.7% [95% CI: 2.9%-16.0%] of patients. Men had higher R-wave amplitudes compared to women (1.40 [0.96-1.80] mV vs 1.00 [0.60-1.20] mV, P = .001), while obese people tended to have lower values (0.80 [0.62-1.28] mV vs 1.10 [0.90-1.50] mV, P = .074). The P-wave visibility reached 86.2% [95% CI: 68.3%-96.1%] in patients with high-voltage P waves (≥0.2 mV) at surface ECG. The sECG quality was not affected by implant site. CONCLUSION: In ordinary clinical practice, ICMs with long sensing vector provided median R-wave amplitude above 1 mV and reliable P-wave visibility of nearly 70%, regardless of the position of the device. Women and obese patients showed lower but still very good signal quality.