Treatment of atrial fibrillation with second-generation cryoballoon followed by contact-sensing radiofrequency catheter ablation for arrhythmia recurrences-results of a 5-year follow-up.

INTRODUCTION: The aim of this study was to report the long-term follow-up results of cryoballoon (CB) ablation in patients with atrial fibrillation. METHODS: All consecutive patients who underwent second-generation CB ablation from February 2015 to December 2017 were included in our study. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. Repeated procedures were performed with a 3D mapping system and radiofrequency catheters. RESULTS: A total of 126 patients (69.8% male, mean age 57 ± 11 years), of which 77.0% had paroxysmal atrial fibrillation (PAF), were included in the study. After a 5-year period, 52.4% of patients were in sinus rhythm without AF recurrence, off antiarrhythmic drugs. A total of 61.9% of patients were free of AF recurrence when redo PVI procedures were performed. When accounting for redo pulmonary vein isolation and antiarrhythmic drugs, a total of 73.8% of the patients were without AF recurrence in long-term follow-up. The patients who underwent redo pulmonary vein isolation procedures had statistically significant lower rates of AF recurrence (p = 0.006). In patients with PAF, long-term success rates improved from 62.9 to 79.4% for patients who underwent the redo procedure (p = 0.020). In patients with persistent atrial fibrillation (PersAF), success rates went up from 41.4 to 55.1% for patients with single or repeated PVI procedure (p = 0.071). In the whole cohort, a total of 3 (2.4%) procedure-related major complications occurred which included persistent PNP, arterial pseudoaneurysm, and arteriovenous fistula. CONCLUSION: Our data suggest a favorable long-term safety and efficacy profile of second-generation CB ablation. In the mixed paroxysmal and persistent population, up to 73.8% of patients remained free of AF recurrence in the 5-year follow-up, when accounting for redo procedures and AADs. Only 2.4% of patients experienced major complications of the ablation procedure, none with permanent sequelae.

Radiation dose reduction in the setting of cryoballoon ablation for atrial fibrillation: the value of optimized fluoroscopy settings and intracardiac echocardiography.

Cryoballoon (CB) has proven to be very effective in the percutaneous treatment of atrial fibrillation (AF). CB ablation is still hampered by X-ray exposure and the doses applied are consistently higher if compared to radiofrequency ablation. All patients who underwent CB ablation between 2015 and 2020 were analysed. Intracardiac echography was consistently used for transeptal puncture. To demonstrate the differences in radiation exposure 3 groups of 50 consecutive patients were selected. In the first group (G1) 3D rotational angiography (3DRA) was used as an intraprocedural imaging method. In the second group (G2), traditional X-ray imaging was used and frame rates both for fluoro and cine modes of diascopy were lowered. In the third group (G3) only 2-3 frames per second were used, cine mode was abandoned and the grid was removed from the X-ray detector. A total of 150 patients were included (76% males, mean age 57.3 ± 11.5 years). A dramatic reduction of radiation dose was obtained from 9585 ± 5610 µGy/m2 in G1 to 2469 ± 2002 µGy/m2 in G2 and finally 227.1 ± 360 µGy/m2 in G3 (p < 0.0001). There was also a significant decrease of procedural and fluoroscopy times. No difference in major complications and midterm outcomes was found between the groups. By following a few relatively simple steps (omitting the pre-procedural imaging, removing grid from the X-ray detector and using very low frame rates) CB ablation could be performed with ultralow radiation exposure without compromising the safety of efficacy of the procedure.

Initial rhythm control with cryoballoon ablation vs drug therapy: Impact on quality of life and symptoms.

BACKGROUND: Cryoballoon ablation (CBA) as a first-line rhythm control strategy is superior to antiarrhythmic drugs (AADs) for preventing atrial fibrillation (AF) recurrence; the impact of first-line CBA on quality of life (QoL) and symptoms has not been well characterized. METHODS: Patients aged 18 to 75 with symptomatic paroxysmal AF naïve to rhythm control therapy were randomized (1:1) to CBA (Arctic Front Advance, Medtronic) or AAD (Class I or III). Symptoms and QoL were assessed at baseline, 1, 3, 6, 9, and 12 months using the EHRA classification and Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) and SF-36v2 questionnaires. Symptomatic palpitations were evaluated via patient diary. RESULTS: Overall, 107 patients were randomized to CBA and 111 to AAD; crossovers occurred in 9%. Larger improvements in the AFEQT summary, subscale and treatment satisfaction scores were observed at 12 months with CBA vs AAD (all P <0.05). At 12 months, the mean adjusted difference in the AFEQT summary score was 9.9 points higher in the CBA group (95% CI: 5.5 -14.2, P <0.001). Clinically important improvements in the SF-36 physical and mental component scores were observed at 12 months in both groups, with no significant between group differences at this timepoint. In the CBA vs AAD group, larger improvements in EHRA class were observed at 6, 9 and 12 months (P <0.05) and the incidence rate of symptomatic palpitations was lower (4.6 vs 15.2 days/year post-blanking; IRR: 0.30, P <0.001). CONCLUSIONS: In patients with symptomatic AF, first-line CBA was superior to AAD for improving AF-specific QoL and symptoms. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01803438.

Cryoballoon ablation vs. antiarrhythmic drugs: first-line therapy for patients with paroxysmal atrial fibrillation.

AIMS: Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). METHODS AND RESULTS: A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P < 0.001). CONCLUSIONS: Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.

Intra-procedural three-dimensional rotational angiography in cryoballoon ablation for atrial fibrillation.

Cryoballoon (CB) is an established technology for atrial fibrillation (AF) ablation and is usually performed using solely fluoroscopy. We aimed to study the feasibility of three-dimensional rotational angiography (3DRA) as intra-procedural imaging in CB ablation. Analyzed data were retrospectively collected from patients that underwent second generation CB ablation from February 2015 to August 2017. We studied 68 consecutive patients that received 3DRA (3DRA group). Sixty-six patients who received conventional X-ray imaging served as a control group. 3DRA was performed via an introducer placed in the left atrium. Angiographic images were segmented and fused with live fluoroscopy to guide the ablation. We have analyzed 134 CB patients (73.8% male, 56.9 ± 11.4 years). Paroxysmal AF was present in 77.6% of patients. 3DRA was successfully performed in all 3DRA group patients. The mean procedure time was significantly shorter in the control group (82.4 ± 26.3 min) than in the 3DRA group (121.1 ± 21.4 min) (p < 0.0001). Total radiation dose (419.3 ± 317.9 vs 998.3 ± 673 mGy, p < 0.0001) and contrast administration (83.2 ± 22.3 mL vs 191.6 ± 33.4 mL, p < 0.0001) were significantly lower in control group. There was no significant difference in 2-year success rate, 35.2% of patients had AF recurrence in the 3DRA group and 30.3% in the control group (p = 0.584). Major complications occurred in 2.9% and 1.5% of patients in 3DRA group and control group, respectively (p = 1.000). 3DRA is a feasible method of intra-procedural imaging to guide CB ablation. However, it prolongs procedure time, increases radiation dose and contrast administration with no significant effect on procedure outcomes and complication rates.

Improved real-time recordings using the fourth-generation cryoballoon technology-detection of dual fascicle electrograms.

BACKGROUND: We aimed to analyze the rate of visualization of real-time (RT) recordings and dual fascicle electrograms in our first series of patients treated with the fourth-generation cryoballoon (CB) device. METHODS: All consecutive patients who underwent CB ablation using the fourth-generation technology were included in the analysis. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. RESULTS: A total of 129 patients (72.9% male, mean age 60.1 ± 10.9 years) were enrolled in the study. RT recordings were detected in 445 (86.2%) pulmonary veins (PVs). Specifically, RT recordings were visualized in 115 left superior PVs (89.2%), 107 left inferior PVs (82.9%), 118 right superior PVs (91.4%), and 105 right inferior PVs (81.3%). Dual fascicle electrograms could be observed only in patients in sinus rhythm, in 23 of 396 PVs (5.8%). They were most commonly observed in the left superior PV (8.1%), somewhat less in both inferior veins (6.1%), while this phenomenon was least frequent in the right superior PV (3.0%). CONCLUSIONS: By using the fourth-generation CB, we report a specific pattern of isolation represented by a sequential isolation of two apparently distinct PV fascicles during a single CB freeze delivery. This phenomenon occurred in 5.8% of PV ablations. Of note, the rate of visualization of RT isolation with this novel CB was very high and could be documented in 86.2% of PVs.

Use of figure of eight suture for groin closure with no heparin reversal in patients undergoing cryoballoon ablation for atrial fibrillation.

PURPOSE: We aimed to demonstrate the feasibility of figure of eight (FoE) suture for groin access closure in cryoballoon (CB) ablation and its impact on the lab workflow. METHODS: We retrospectively analyzed all patients who underwent CB ablation in our institution from June 2018. From June 2019, we have been consistently using FoE suture for hemostasis (FoE+ group), and before that conventional manual compression was utilized (FoE- group). Ablations were performed under uninterrupted oral anticoagulant strategy. Both femoral veins were punctured, and a single introducer was placed in each vein. In the FoE- group, after ablation, protamine was administered, and manual compression was applied. In the FoE+ group, the suture was placed in both groins without protamine administration and manual compression. All patients were in decubitus position until the next morning. RESULTS: A total of 190 consecutive patients (73.2% male, 59.7 ± 11.0 years old) were evaluated, 90 being in the FoE+ group. There was no difference in the mean procedure duration between two groups (72.7 ± 23.1 min vs 73.7 ± 27.1 min, p = 0.784). However, the total lab time was significantly longer in FoE- group (132.9 ± 35.3 min vs 109.9 ± 32.6 min, p < 0.0001). There was no difference in complication rates. No major vascular complications were found in our cohort. CONCLUSIONS: Utilization of FoE sutures for hemostasis seems to be a safe and effective after cryoballoon ablation. It abolishes the need for protamine administration which can cause serious adverse events. As manual compression is unrequired, EP lab workflow improves due to significantly shortened total lab time per patient.

Cryoballoon catheter ablation versus antiarrhythmic drugs as a first-line therapy for patients with paroxysmal atrial fibrillation: Rationale and design of the international Cryo-FIRST study.

BACKGROUND: Radiofrequency current (RFC) catheter ablation for patients with paroxysmal atrial fibrillation (AF) has been shown to be safe and effective in first-line therapy. Recent data demonstrates that RFC ablation provides better clinical outcomes compared to antiarrhythmic drug (AAD) in the treatment of early AF disease. Furthermore, studies comparing RFC and cryoballoon have established comparable efficacy and safety of pulmonary vein isolation (PVI) for patients with symptomatic paroxysmal AF. OBJECTIVES: The Cryo-FIRST trial was designed to compare AAD treatment against cryoballoon PVI as a first-line therapy in treatment naïve patients with AF. Efficacy and safety will be compared between the two cohorts and amongst subgroups. METHODS: The primary hypothesis is that cryoablation is superior to AAD therapy. To test this hypothesis, patients will be randomized in a 1:1 design. Using a 90-day blanking period, primary efficacy endpoint failure is defined as (at least) one episode of atrial arrhythmia with a duration >30 sec (documented by 7-day Holter or 12-lead ECG). Secondary endpoints (Quality-of-Life, rehospitalization, arrhythmia recurrence rate, healthcare utilization, and left atrial function) and adverse events will also be evaluated. Study enrollment will include 218 patients in up to 16 centers. CONCLUSIONS: This study will be a multi-national randomized controlled trial comparing cryoablation against AAD as a first-line treatment in patients with paroxysmal AF. The results may help guide the selection of patients for early AF disease therapy via cryoballoon ablation.

Electrocardiographic and clinical predictors of permanent pacemaker insertion following Perceval sutureless aortic valve implantation.

BACKGROUND: Sutureless aortic valve replacement surgery (AVR) is a reasonable alternative surgical approach in those patients with aortic stenosis who would benefit from reduced cross clamp time, such as elderly and high-risk patients. We sought to evaluate the incidence of pacemaker (PM) implantation following sutureless AVR and to analyse possible pre-operative electrocardiographic and clinical predictors of PM implantation. METHODS AND RESULTS: Between November 2013 and March 2015, 58 patients (male 43%, age 77.9 ±â€¯4.9 years) having undergone sutureless AVR with a Perceval prosthesis (Sorin Biomedica Cardio Srl, Saluggia, Italy) were taken into consideration for our analysis. During a mean follow up of 13.8 ±â€¯5.0 months (median 13 months), 14 patients (24.1%) underwent pacemaker (PM) implantation following sutureless AVR procedure. Among these patients, 12 (86%) presented III degree atrioventricular (AV) block, 1 (7%) presented II degree AV block, and remaining one (7%) severe symptomatic bradycardia. The comparison of pre-operative characteristics between PM group and no PM group highlighted that QRS duration, EuroSCORE II index and chronic renal dysfunction were significantly associated with the development of AV conduction abnormalities/symptomatic bradycardia requiring PM implantation (respectively, p = 0.01, p = 0.02 and p = 0.03). CONCLUSIONS: The incidence of PM implantation after sutureless AVR was 24.1% in the present study. The EuroSCORE II, QRS duration and renal dysfunction were significantly associated with higher risk of AV conduction abnormalities/symptomatic bradycardia requiring PM placement.

Clinical value of induction protocol after second generation cryoballoon ablation for paroxysmal atrial fibrillation.

Aims: The predictive value of induction studies after catheter ablation for atrial fibrillation (AF) is still debatable. To date, these studies have not been implemented in patients after cryoballoon (CB) ablation. Our aim was to analyse the clinical value of AF induction in patients treated by second generation CB for paroxysmal AF. Methods and results: Seventy patients underwent at first an isoproterenol challenge after pulmonary vein (PV) isolation to assess AF induction and early PV reconnections (EPVR). Patients without EPVR were evaluated for premature atrial contraction (PAC) induction; atrial ectopy was considered frequent (PAC+) if >1/10 cycles or >6/min. After restitution of baseline heart rate, rapid atrial pacing (RAP) was performed on all patients. AF induction by isoproterenol occurred only in 3/70 (4%) patients of whom 2/3 (66%) patients with an EPVR of a triggering vein. In the 62 patients without EPVR, PAC+ occurred in 17 patients (27%). RAP could induce AF in 23/70 (33%) patients. At a mean follow-up of 13.5 months, there were 11/70 (16%) AF recurrences. There was no significant difference in the AF recurrence rate between RAP inducible vs. non-inducible patients (log-rank P = 0.33). A 41% recurrence rate (7/17 patients) was seen in the PAC+ group with significantly different AF-free survival for PAC+ vs. PAC- patients (log rank P < 0.0001). PAC+ was the only independent determinant to predict AF recurrence after multivariate analysis. Conclusion: PAC occurrence in response to isoproterenol could predict AF recurrence after PV isolation by CB, while RAP showed no prognostic implication.

Role of Electrocardiographic Tpeak-Tend for the Prediction of Ventricular Arrhythmic Events in the Brugada Syndrome.

Some previous studies have proposed the electrocardiographic Tpeak-Tend (TpTe) as a possible predictor of ventricular arrhythmic events in patients with Brugada syndrome (BrS). We sought to analyze the association between the parameters of repolarization dispersion (TpTe, TpTe/QT, TpTe dispersion, QTc, and QTd) and ventricular fibrillation/sudden cardiac death in a large cohort of patients with type 1 BrS. A total of 448 consecutive patients with BrS (men 61%, age 45 ± 16 years) with spontaneous (n = 96, 21%) or drug-induced (n = 352, 79%) type 1 electrocardiogram were retrospectively included. At the time of the diagnosis or during a mean follow-up of 93 ± 47 months (median 88 months), 43 patients (9%) documented ventricular arrhythmias. No significant difference was observed in TpTe, TpTe/QT, maximum TpTe, and TpTe dispersion between asymptomatic patients and those with syncope and malignant arrhythmias. TpTe/QT ratio did not also significantly differ between patients with ventricular fibrillation/sudden cardiac death and those asymptomatic ones. In conclusion, TpTe was not significantly prolonged in those patients with type 1 BrS presenting with unexplained syncope or malignant arrhythmic events during follow-up.

Second-generation cryoballoon ablation in the setting of left common pulmonary veins: Procedural findings and clinical outcome.

BACKGROUND: A left common pulmonary vein (LCPV) accounts for the most frequent PV variation. Use of the cryoballoon (CB) for isolating these veins is still debatable. To date, no data are available regarding the feasibility, acute PV isolation, and clinical outcome of the second-generation CB (CB-A) in this setting. OBJECTIVE: The purpose of this study was to investigate the performance of the CB-A in patients with LCPVs. METHODS: In a total cohort of 433 patients having undergone CB-A ablation for drug-refractory atrial fibrillation together with preprocedural computed tomographic scanning, 146 patients presented an LCPV. Measurement of ostial area and trunk distance was performed, together with analysis of procedural and fluoroscopic data in order to determine the ablation strategy. The latter 146 LCPV+ patients were compared for outcome with a cohort of 146 propensity-score matched LCPV- patients. RESULTS: Electrical isolation could be achieved in all left-sided veins. A long left common trunk (>15 mm) was found in 25% (37/146) of the LCPV+ patients. LCPVs treated with a single-shot freeze strategy presented a longer trunk (22 ± 5 mm vs 9 ± 4 mm, P <.001) and smaller ostial area (305 ± 109 mm2 vs 400 ± 108 mm2, P <.001) compared to LCPV patients in whom a segmental (superior and inferior) freeze was delivered. Survival free from atrial fibrillation was similar between LCPV+ and LCPV- patients during mean follow-up of 19 ± 10 months (log rank P = .33). CONCLUSION: CB-A ablation in LCPV+ patients is effective and showed no difference in clinical outcome compared to LCPV- patients.

Midterm clinical outcomes of concomitant thoracoscopic epicardial and transcatheter endocardial ablation for persistent and long-standing persistent atrial fibrillation: a single-centre experience.

AIMS: The purpose of this study was to analyse the efficacy and complication rates of the simultaneous hybrid procedure in a series of patients with persistent and long-standing persistent atrial fibrillation (AF) in a midterm follow-up. METHODS AND RESULTS: Sixty-four consecutive patients (56 males, 59.7 ± 8.7 years) having undergone isolation of pulmonary veins (PVs) and posterior wall of left atrium (LA) by means of hybrid thoracoscopic ablation for symptomatic persistent (n = 21, 33%) and long-standing persistent AF (n = 43, 67%) were analysed. At a mean follow-up of 23.1 ± 14.1 months (median 21; range 6-57), the success rate without antiarrhythmic therapy was achieved in 67.2% of patients. Procedure-related complications were observed in 13 patients (20.3%) including 2 LA perforations (3.1%) requiring, respectively, conversion to sternotomy and small left-sided thoracotomy. The success rate did not significantly differ between persistent and long-standing persistent AF (respectively, 71.4 and 65.1%; P = 0.4). Patients with AF relapse during the blanking period were 4.60 times more likely to have AF recurrence after 3 months from the ablation procedure. CONCLUSION: The hybrid procedure yields promising results in the setting of both persistent and long-standing persistent AF after midterm follow-up, at the expense of a non-negligible rate of adverse events. Our findings need to be confirmed by further larger and prospective studies.

Learning curve using the second-generation cryoballoon ablation.

AIMS: To study the learning curve with the second-generation cryoballoon technology focusing on safety, efficacy and procedural characteristics. METHODS: We included 300 patients (men 64.6%, mean age 58.3 ±â€Š12.4 years), 240 of whom were treated by four operators without prior experience in atrial fibrillation ablation and compared them with 60 consecutive patients treated by senior operator. To study the learning curves, we divided the study period into two trimesters and analyzed procedure duration, fluoroscopy times, complications, characteristics of the freeze-thaw cycles and midterm outcomes. RESULTS: Hands-on help from senior operators to achieve pulmonary vein isolation was needed only in the first study trimester (24.1%), most commonly to achieve right inferior pulmonary vein isolation (55.2%). The mean procedure duration shortened from 76.7 ±â€Š17.4 to 65.1 ±â€Š11.4 min (P < 0.0001), and fluoroscopy time decreased from 18.5 ±â€Š7.3 to 12.1 ±â€Š4.3 min (P < 0.0001) for first and second trimester, respectively, and approached senior operator's results (58.2 ±â€Š12.8 and 8.7 ±â€Š4.5 min). Most of the major complications (one stroke, four pseudoaneurysms and one retroperitoneal hematoma) occurred during the first study trimester. Most characteristics of the freeze cycles remained unchanged in both study periods. Compared with junior operators, the senior operator achieved lower nadir temperatures in both inferior veins. However, there was no significant difference in midterm outcomes between junior and senior operators (79.5 vs 83.3%, P = 0.589). CONCLUSION: The learning curve with the second-generation cryoballoon is steep. Inexperienced operators, trained in high-volume centers, can achieve pulmonary vein isolation safely and efficiently with short procedure and fluoroscopy times after having performed 20-30 cases.

Single 3-Minute versus Double 4-Minute Freeze Strategy for Second-Generation Cryoballoon Ablation: A Single-Center Experience.

INTRODUCTION: Second-generation cryoballoon (CB-Adv) ablation is highly effective in achieving pulmonary vein isolation (PVI) with promising mid-term clinical outcome. However, the ideal freezing strategy is still under debate. The aim of this study was to assess the efficacy of a single 3-minute approach compared to the conventional 4-minute plus bonus application using CB-Adv. METHODS AND RESULTS: One hundred and sixty patients (67% male; mean age 58.0 ± 13.3 years) underwent PVI using CB-Adv for paroxysmal atrial fibrillation (PAF). Among 160 patients, 80 received a single 3-minute approach (3-mns group), while the remaining 80 conventional 4-minute plus bonus-freeze (4-mns group). Mean procedure and fluoroscopy times were 90.6 ± 15.8 and 18.3 ± 6.9 in the 4-mns group, 75.2 ± 17.1 and 13.5 ± 8.7 in the 3-mns group (P < 0.001, respectively). First-freeze isolation rate was 91.6% in the 4- versus 90.6% in the 3-mns group (P = 0.78). Persistent phrenic nerve palsy (PNP) occurred in 6/80 (3.5%) in the 4-mns group and 4/80 in the 3-mns group (P = 0.75). The overall freedom from ATas 2 years after the procedure was 78.1% (125/160): 77.5% (62/80 patients) in the 3-mns and 78.8% (63/80 patients) in the 4-mns group (P = 0.82). In multivariate analysis, time to PVI and nadir temperature independently predicted ATa recurrences (P < 0.001). CONCLUSIONS: CB-Adv ablation for PAF is highly effective, resulting in 78% 2-year freedom from arrhythmic recurrences. A "single 3-minute strategy" showed equal efficacy as compared to the conventional 4-minute plus bonus freeze approach at 2-year follow-up, providing shorter procedure and fluoroscopy time. Nadir temperature and time to PVI were predictors of arrhythmic recurrences. "Bonus-freeze" strategy might be unnecessary.

Incidence of real-time recordings of pulmonary vein potentials using the third-generation short-tip cryoballoon.

AIMS: The third-generation Cryoballoon Advance Short-tip (CB-ST) has been designed with a 40% shortened tip length compared with the former second-generation CB Advance device. Ideally, a shorter tip should permit an improved visualization of real-time (RT) recordings in the pulmonary vein (PV) due to a more proximal positioning of the inner lumen mapping catheter. In the present study, we sought to analyse the rate of visualization of RT recordings in our first series of patients with the CB-ST device. METHODS AND RESULTS: All consecutive patients having undergone CB ablation using CB-ST technology were analysed. Exclusion criteria were the presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, and contraindications to general anaesthesia. A total of 60 consecutive patients (60.5 ± 11.2 years, 62% males) were evaluated. Real-time recordings were detected in 209 of 240 PVs (87.1%). Specifically, RT recordings could be visualized in 55 left superior PVs (91.7%), 51 left inferior PVs (85.0%), 53 right superior PVs (88.3%), and 50 right inferior PVs (83.3). CONCLUSION: The rate of visualization of RT recordings is significantly high during third-generation CB-ST ablation. Real-time recordings can be visualized in ∼87.1% of veins with this novel cryoballoon.

Second-generation cryoballoon ablation for paroxysmal atrial fibrillation: Predictive role of atrial arrhythmias occurring in the blanking period on the incidence of late recurrences.

BACKGROUND: Although consensus documents on catheter and surgical ablation of atrial fibrillation (AF) suggest a uniform "blanking period" of 3 months, recent evidence suggested that early recurrences of atrial tachyarrhythmias (ERATs) are strongly associated with late recurrences (LRs), especially if ERATs occurred in the last part of the "blanking period". OBJECTIVE: The present study sought to assess the role of ERATs in predicting LRs in a large cohort of patients with paroxysmal AF who have undergone second-generation cryoballoon ablation. METHODS: Consecutive patients with drug-resistant paroxysmal AF who underwent pulmonary vein isolation using CB-A technology as the index procedure were retrospectively included in our analysis. The exclusion criteria were any contraindications for the procedure, including the presence of an intracavitary thrombus, uncontrolled heart failure, contraindications to general anesthesia, and persistent AF. RESULTS: A total of 331 consecutive patients (104 women [31%]; mean age 56.7 ± 13.3 years) were enrolled. Atrial tachyarrhythmias/AF recurrences were detected in 57 patients (17.2%). The highest prevalence of ERATs was observed in the first 2 weeks (55%) after pulmonary vein isolation. Of note, all the ERATs occurring 1.5 months after AF ablation relapsed after 3 months and were confirmed as definitive recurrences. Late recurrence of AF and atrial tachycardia occurred in 20 of 29 patients with ERATs (69.0%) and 28 of 302 patients without ERATs (9.3%) (P < .0001). A multivariate Cox regression analysis showed that the early recurrence within the blanking period was significantly and independently associated with an increased risk of developing a late recurrence (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001). CONCLUSION: Our findings reveal that ERATs are strongly associated with an LR after paroxysmal AF ablation using CB-A technology (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001). Of note, when ERATs occurred later than 1.5 months, patients systematically experienced an LR.

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.

Phrenic nerve injury during ablation with the second-generation cryoballoon: analysis of the temperature drop behaviour in a large cohort of patients.

AIMS: The present study sought to analyse the relationship between the temperature drop during the cryoenergy application and the occurrence of phrenic nerve injury (PNI) in a large cohort of patients having undergone second-generation cryoballoon ablation (CB-A). METHODS AND RESULTS: The first 550 consecutive patients having undergone CB-A for atrial fibrillation were enrolled. Attained temperatures at 20, 30, 40, and 60 s during cryoablation in the right-sided pulmonary veins (PVs) were collected. Diagnosis of PNI was made if reduced motility or paralysis of the hemidiaphragm was detected. The incidence of PNI in the study population was 7.3% (40/550); among them, only four (0.7%) did not resolve until discharge and one (0.2%) still persisted at 23 months. Patients with PNI exhibited significantly lower temperatures at 20, 30, and 40 s after the beginning of the cryoapplication in the right superior PV (RSPV) (P = 0.006, P = 0.003, and P = 0.003, respectively). The temperature drop expressed as Δ temperature/Δ time was also significantly higher in patients with PNI. Low temperature during the early phases of the freezing cycle (less than -38°C at 40 s) predicted PNI with a sensitivity of 80.5%, a specificity of 77%, and a negative predictive value of 97.9%. Among patients with a fast temperature drop during RSPV ablation, an RSPV diameter >23.55 × 17.95 mm significantly predicted PNI occurrence. CONCLUSION: The analysis of the temperature course within the first 40 s after the initiation of the freezing cycle showed that the temperature dropped significantly faster in patients with PNI during ablation in the RSPV.

Repeat Procedures After Hybrid Thoracoscopic Ablation in the Setting of Longstanding Persistent Atrial Fibrillation: Electrophysiological Findings and 2-Year Clinical Outcome.

INTRODUCTION: In order to increase success rates of invasive treatment of persistent atrial fibrillation, the hybrid approach was developed, combining video-assisted thoracoscopic epicardial procedure with conventional endocardial catheter ablation. Currently, there are no reports of electrophysiological findings and clinical outcomes of repeat procedures after the hybrid approach. METHODS AND RESULTS: Out of 64 patients who were treated by hybrid ablation for persistent atrial fibrillation (AF), 14 underwent the repeat catheter ablation and were selected for this study. All 14 patients initially presented with longstanding persistent atrial fibrillation and markedly dilated atria. The hybrid procedure was performed in a single act and the mean time to redo procedure was 346 ± 227 days. In 57% of patients indication for redo procedure was regular atrial tachycardia, and the rest presented with recurrent atrial fibrillation. In 36% of patients, recovered conduction was found along the previous ablation lesions. Only 9% of pulmonary veins were reconnected (0.36 veins per patient) and 7% of box lesions were not complete. The overall success rate at 2 years follow-up after the repeat procedure, including second repeat procedure and patients taking antiarrhythmic drugs, was 64% (57% without drugs and further ablation). One case of moderate pulmonary vein stenosis was detected as a consequence of hybrid procedure. CONCLUSION: Hybrid atrial fibrillation ablation results in durable lesions and high rates of chronic pulmonary vein isolation even after long-term follow-up. Most of the repeat procedures after the hybrid approach are related to left atrial flutters that could be successfully treated by catheter ablation.