Giacomo Mugnai

Second-generation cryoballoon ablation for paroxysmal atrial fibrillation: 1-year follow-up.

BACKGROUND The novel cryoballoon Advance (CB-A) has proven to achieve significantly lower temperatures and faster pulmonary vein isolation (PVI) times in comparison with the first-generation device. Although acutely very effective, to the best of our knowledge, data on mid-term clinical follow-up is lacking. AIMS The aim of the study was to analyse the freedom from recurrence of atrial fibrillation (AF) on a 1-year follow-up period, in a series of consecutive patients having undergone PVI with the CB-A for paroxysmal AF (PAF). METHODS AND RESULTS Forty-two patients [30 male (71%); mean age: 57.9 ± 21.1 years] were included. All patients underwent a procedure with the large 28 mm CB-A. A total 168 PVs were depicted on the pre-procedural computed tomography scan. All PVs (100%) could be isolated with the CB only. The freedom from AF off-antiarrhythmic drug treatment after a single procedure was 78% of patients at a mean 11.6 ± 2.0 months follow-up. If considering a blanking period (BP) of 3 months, success rate was 83%. Phrenic nerve palsy (PNP) was the most frequent complication occurring in 19% of individuals. CONCLUSION The CB-A is very effective in producing PVI and affords freedom from AF at 12 months follow-up in 83% of patients affected by drug-resistant PAF following a 3-month BP. The most frequent complication observed was PNP which occurred in 19% of patients. All PNP reverted during follow-up.

Pulmonary vein isolation as index procedure for persistent atrial fibrillation: One-year clinical outcome after ablation using the second-generation cryoballoon

BACKGROUND No data are available about the clinical outcome of pulmonary vein isolation (PVI) as an index procedure for persistent atrial fibrillation (PersAF) ablation using the second-generation cryoballoon (CB-Adv). OBJECTIVE The purpose of this study was to assess the 1-year efficacy of PVI as an index procedure for PersAF ablation using the novel CB-Adv. METHODS Sixty-three consecutive patients (45 male [71.4%], mean age 62.7 ± 9.7 years) with drug-refractory PersAF undergoing PVI using the novel CB-Adv were enrolled. Follow-up was based on outpatient clinic visits including Holter ECGs. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 seconds. RESULTS A total of 247 PVs were identified and successfully isolated with a mean of 1.7 ± 0.4 freezes. Mean procedural and fluoroscopy times were 87.1 ± 38.2 minutes and 14.9 ± 6.1 minutes, respectively. Among 26 of 63 patients (41.3%) presenting with AF at the beginning of the procedure, 7 of 26 (26.9%) converted to sinus rhythm during ablation. Phrenic nerve palsy occurred in 4 of 63 patients (6.3%). At 1-year follow-up, after a 3-month blanking period (BP), 38 of 63 patients (60.3%) were in sinus rhythm. Because of ATa recurrences, 9 patients underwent a second procedure with radiofrequency ablation showing a pulmonary vein reconnection in 4 right-sided PVs (44.4%) and 3 left-sided PVs (33.3%). Multivariate analysis demonstrated that PersAF duration (P = .01) and relapses during BP (P = .04) were independent predictors of AT recurrences. CONCLUSION At 1-year follow-up, freedom from ATas following PersAF ablation with the novel CB-Adv is 60%. Phrenic nerve palsy is the most common complication. PersAF duration and relapses during the BP appear to be significant predictors of arrhythmic recurrences.

Circumferential pulmonary vein isolation as index procedure for persistent atrial fibrillation: a comparison between radiofrequency catheter ablation and second-generation cryoballoon ablation

AIMS To assess the 1 year efficacy of pulmonary vein isolation (PVI) as index procedure for persistent atrial fibrillation (PersAF) comparing conventional radiofrequency irrigated-tip catheter ablation (RFCA) using contact-force technology and ablation using the second-generation cryoballoon (CB-AdvA). METHODS AND RESULTS One hundred consecutive patients (74 male, 74%; mean age 62.4 ± 9.6 years) with drug-refractory PersAF undergoing PVI using RFCA and CB-AdvA were enrolled. Follow-up was based on outpatient clinic visits including Holter-electrocardiograms. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 s. Among 100 patients, 50 underwent RFCA whereas 50 CB-AdvA. Mean procedure and fluoroscopy times were 90.5 ± 41.7 vs. 140.2 ± 46.9 min and 14.5 ± 6.6 vs. 19.8 ± 6.8 min in the CB-Adv and in the RFCA group, respectively (P < 0.01). At 1 year follow-up, after a 3 months blanking period (BP), freedom from ATas off-drugs after a single procedure was 60% (28/50 patients) in the CB-Adv and 56% (27/50 patients) in the RFCA group (P = 0.71). Multivariate analysis demonstrated that PersAF duration (P = 0.01) and relapses during BP (P = 0.02) were independent predictors of ATa recurrences following the index procedure. CONCLUSION Freedom from ATas following PersAF ablation with RFCA and CB-Adv is comparable at 1 year follow-up after a single procedure. Ablation with the CB-Adv is associated with shorter procedure time and radiation exposure as compared with RFCA. Atrial tachyarrhythmias occurrence during BP and longer time of PersAF seem to be significant predictors of arrhythmia recurrences after the index procedure.

On the Quest for the Best Freeze: Predictors of Late Pulmonary Vein Reconnections After Second-Generation Cryoballoon Ablation.

Background—The second-generation cryoballoon is effective in achieving acute pulmonary vein isolation (PVI) and favorable clinical outcome. To date, no data are available on factors affecting late PV reconnection after second-generation cryoballoon ablation. Methods and Results—A total of 29 consecutive patients (25 male, 86.2%; mean age 57.8±13.8 years) underwent a repeat procedure, after a mean 11.6±4.5 months (range, 3.5–19.7 months), after index ablation using the 28-mm second-generation cryoballoon. All repeat ablations were performed using a 3-dimensional electroanatomical mapping system. Among all 115 PVs, including 1 left common ostiums (LCOs), 25 (21.7%) showed a PV reconnection in 20 patients (1.25 per patient). Persistent PVI could be documented in 90 of 115 PVs (78.2%). In 9 of 29 patients (31%), all PVs were electrically isolated. In the multivariable analysis, time to PVI (P=0.03) and failure to achieve −40°C within 60 s (P=0.05) independently predicted late PV reconnection. At receiver-operator curve analysis, time to PVI <60 s identified the absence of PV reconduction (sensitivity, 86.7%; specificity, 86.2%; positive predictive value, 59.1%; and negative predictive value, 96.4%; area under the curve, 0.85; confidence interval, 0.73–0.97; P<0.001). Conclusions—The rate of late PV reconnection after second-generation cryoballoon ablation is low (1.25 PVs/patient). Faster time to isolation and achievement of −40°C within 60 s independently predict durable PVI. In addition, 60-s cut-off for time to PVI indicates persistent isolation with 96.4% negative predictive value. These parameters might guide the operator whether to perform further applications to ensure a long-lasting PVI.

Incidence and characteristics of complications in the setting of second-generation cryoballoon ablation: A large single-center study of 500 consecutive patients

BACKGROUND The second-generation cryoballoon Advance (CB-A) recently launched on the market has technical modifications designed to significantly improve procedural outcome with respect to the first-generation device. OBJECTIVE The purpose of this study was to evaluate the overall incidence of complications in a large sample of patients having undergone pulmonary vein (PV) isolation with CB-A technology. METHODS All consecutive patients who underwent PV isolation procedures using CB-A technology between June 2012 and February 2015 were considered. Exclusion criteria were presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, left atrial diameter ≥55 mm, and contraindications to general anesthesia. RESULTS During the study period, 500 consecutive patients (67% male, age 57.6 ± 12.9 years) were enrolled. Major complications occurred in 10 patients (2.0%): vascular complications at the puncture site in 6 (1.2%), and thromboembolic events, cardiac tamponade, persisting phrenic nerve palsy, and retroperitoneal hematoma all occurred in a single patient respectively (0.2%). Phrenic nerve palsy occurred in 36 patients (7.2%) and did not revert in only 1 patient at final follow-up of 20 months. No deaths related to the procedure occurred. No predictors of major complication were found. CONCLUSION The present findings highlight that PV isolation using CB-A technology can be safely performed with a low incidence of adverse events. The incidence of major complications after atrial fibrillation ablation procedures using CB-A technology was 2% in our study. The most frequent complication consisted of vascular complications at the puncture site. No deaths related to the procedure occurred.

Procedural and biophysical indicators of durable pulmonary vein isolation during cryoballoon ablation of atrial fibrillation

BACKGROUND Limited data exist on procedural and biophysical indicators of pulmonary vein (PV) isolation durability after the cryoballoon ablation of atrial fibrillation (AF). OBJECTIVE The aim of this study was to investigate the procedural and biophysical characteristics associated with late PV reconnection (PVR) and durable PV isolation (PVI) after cryoablation using the currently available second-generation cryoballoon. METHODS Data from 435 PVs targeted in 112 consecutive patients who underwent a repeat procedure 14 ± 3 months after an index cryoablation of AF were examined. RESULTS Altogether, 111 PVs (25.5%) in 71 patients (63.4%) demonstrated PVR, whereas 324 PVs (74.5%) exhibited PVI. The number and duration of cryoballoon applications did not differ between PVR and PVI. However, the time to PV isolation (time to effect) was considerably shorter (39.1 ± 11.7 seconds vs 67.6 ± 19.7 seconds; P < .001), the balloon temperature at time to effect was significantly warmer (-32.1°C ± 7.8°C vs -39.4°C ± 5.8°C; P < .001), the balloon nadir temperature was slightly cooler (-48.7°C ± 4.6°C vs -47.8°C ± 2.9°C; P = .034), and the total thaw time (56.5 ± 25.4 seconds vs 34.8 ± 9.1 seconds; P < .001) and interval thaw times at 0°C (iTT0; 14.8 ± 10.9 seconds vs 7.1 ± 2.0 seconds; P < .001) and 15°C (54.2 ± 25.4 seconds vs 33.3 ± 9.1 seconds; P < .001) were notably longer with PVI than with PVR. However, only a time to effect of ≤60 seconds and an iTT0 of ≥10 seconds emerged as significant predictors of PV isolation durability. Consequently, in a multivariate model, presence of both criteria predicted <1% and their mere absence ~75% likelihood of PVR. CONCLUSION A time to effect of ≤60 seconds and an iTT0 of ≥10 seconds significantly predict PV isolation durability after the cryoballoon ablation of AF. If both criteria are met, the likelihood of PV reconnection may be exceedingly low.

Electrophysiological findings following pulmonary vein isolation using radiofrequency catheter guided by contact-force and second-generation cryoballoon: lessons from repeat ablation procedures.

AIMS To assess the incidence of late pulmonary vein (PV) reconnection following index PV isolation (PVI) procedure initially achieved with radiofrequency contact-force catheter ablation (CFCA) and second-generation cryoballoon ablation (CB-AdvA). METHODS AND RESULTS A total of 56 consecutive patients (41 male, 73.2%; mean age 60.8 ± 11.8 years) underwent a repeat ablation because of recurrent atrial tachyarrhythmias (ATas) after index PVI achieved with CFCA (30 patients) or CB-AdvA (26 patients). All repeat procedures were performed by the means of CFCA. In the CFCA group, among 119 PVs, 43 (36.1%) showed conduction gaps in 24 patients (1.8 per patient), whereas in the CB-AdvA group among 103 veins, 21 (20.4%) showed a PV reconnection in 18 patients (1.2 per patient) (P = 0.01). The left superior pulmonary vein was less frequently reconnected following CB-AdvA when compared with CFCA (2/25, 8% vs. 11/29, 37.9%; P = 0.01). In the CFCA group, the mean CF per-vein was lower in reconnecting veins when compared with those persistently isolated (10.9 ± 2.7 vs. 18.6 ± 3.1 g; P < 0.001). In the CB-AdvA group, late PV reconnection was associated with warmer nadir temperature (-48.9 ± 5.1 vs. -51.2 ± 4.7°C; P = 0.05) and longer time-to-isolation (71.1 ± 20.2 vs. 50.2 ± 32.9 s; P = 0.03). CONCLUSION The rate of late PV reconnection is significantly lower following CB-AdvA when compared with CFCA as index procedure. Lower CF values and warmer nadir temperature with longer time to effect were more frequently associated with PV reconnections in the setting of CFCA and CB-AdvA.

Complications in the setting of percutaneous atrial fibrillation ablation using radiofrequency and cryoballoon techniques: A single-center study in a large cohort of patients

BACKGROUND The aim of this study was to assess the overall incidence of complications in a large sample of consecutive patients having undergone pulmonary vein (PV) isolation, evaluating also the rate of complications in radiofrequency (RF) and cryoballoon (CB) ablation technologies. METHODS AND RESULTS From January 2008 to December 2014, 1352 consecutive PV isolation procedures were performed in our center; a total amount of 1233 AF ablation procedures fulfilling inclusion criteria was finally taken into consideration for our analysis. A total of 642 procedures were performed using RF ablation technology and 591 using CB system. Serious adverse events occurred in 36 procedures (2.9%): specifically, vascular complications in 14 (1.1%); cardiac tamponade in 13 (1.0%); a thromboembolic event in 4 (0.3%); and atrial-esophageal fistula, PV intramural hematoma, retroperitoneal hematoma, pleural hematoma and persisting phrenic nerve palsy all occurred in 1 patient individually (0.1%). No deaths related to the procedure occurred. The complication rate did not significantly differ in the RF and CB groups (respectively, 3.6% vs 2.2%; p=0.1). Complication rates considerably decreased over the study period from 4.67% in 2008 to 1.55% in 2014. Interestingly, each 1-point increase in the CHA2DS2-VASc score was found to increase by 51% the likelihood of a serious adverse event. CONCLUSIONS The incidence of serious adverse events following AF ablation procedures was 2.9%. Vascular complications were the most frequent complication followed by tamponade and thromboembolic events. The rate of complications considerably decreased over time. CHA2DS2-VASc score was found to be associated with higher risk of complications.

A score model to predict risk of events in patients with Brugada Syndrome

Aims Risk stratification in Brugada Syndrome (BS) remains challenging. Arrhythmic events can occur life-long and studies with long follow-ups are sparse. The aim of our study was to investigate long-term prognosis and risk stratification of BS patients. Methods and results A single centre consecutive cohort of 400 BS patients was included and analysed. Mean age was 41.1 years, 78 patients (19.5%) had a spontaneous type I electrocardiogram (ECG). Clinical presentation was aborted sudden cardiac death (SCD) in 20 patients (5.0%), syncope in 111 (27.8%) and asymptomatic in 269 (67.3%). Familial antecedents of SCD were found in 184 individuals (46.0%), in 31 (7.8%) occurred in first-degree relatives younger than 35 years. An implantable cardioverter defibrillator (ICD) was placed in 176 (44.0%). During a mean follow-up of 80.7 months, 34 arrhythmic events occurred (event rate: 1.4% year). Variables significantly associated to events were: presentation as aborted SCD (Hazard risk [HR] 20.0), syncope (HR 3.7), spontaneous type I (HR 2.7), male gender (HR 2.7), early SCD in first-degree relatives (HR 2.9), SND (HR 5.0), inducible VA (HR 4.7) and proband status (HR 2.1). A score including ECG pattern, early familial SCD antecedents, inducible electrophysiological study, presentation as syncope or as aborted SCD and SND had a predictive performance of 0.82. A score greater than 2 conferred a 5-year event probability of 9.2%. Conclusions BS patients remain at risk many years after diagnosis. Early SCD in first-degree relatives and SND are risk factors for arrhythmic events. A simple risk score might help in the stratification and management of BS patients.

One-year follow-up after second-generation cryoballoon ablation for atrial fibrillation in a large cohort of patients: a single-centre experience

AIM The second-generation cryoballoon (CB-Adv) is effective in achieving pulmonary vein isolation (PVI) with encouraging results. In this study, we assessed the single-procedure outcome on a 1-year follow-up period in a large sample of patients having undergone PVI for drug-resistant atrial fibrillation (AF) using the CB-Adv. METHODS AND RESULTS A total of 393 patients (122 female, 31%; mean age 57.7 ± 12.9 years) with drug-refractory AF undergoing PVI using the novel CB-Adv were enrolled. Follow-up was based on outpatient clinic visits including Holter electrocardiograms. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 s. A total of 1572 pulmonary veins (PVs) were identified and successfully isolated with 1.2 ± 0.3 mean freezes. Mean procedure and fluoroscopy times were 87.1 ± 38.2 and 14.9 ± 6.1 min, respectively. At a mean follow-up of 12 months, freedom from ATas after a single procedure was achieved in 85.8% of patients with paroxysmal atrial fibrillation and in 61.3% of patients with persistent AF (persAF). Similar success rates were observed between bonus freeze and single freeze strategies, 82.5 and 81.8%, respectively (P = 0.9). Multivariate analysis demonstrated that persAF (P = 0.04) and relapses during blanking period (BP) (P < 0.0001) were independent predictors of ATas recurrences. CONCLUSION Freedom from any ATa can be achieved in 81.9% of patients after a single CB-Adv procedure in a large cohort of patients. A bonus freeze does not influence the clinical outcome, and reducing the duration of the cryoapplication to 3 min offers excellent results. Persistent AF and arrhythmia recurrence during the BP are strong predictors of AF recurrence.