Radiofrequency versus cryoballoon ablation for atrial fibrillation in the setting of left common pulmonary veins.

BACKGROUND: A left common pulmonary vein (LCPV) accounts as the most frequent pulmonary vein (PV) variation. Our aim was to compare the performance of radiofrequency (RF) versus second-generation cryoballoon (CB-A) ablation in patients with atrial fibrillation (AF) and LCPVs. METHODS: In a total cohort of 716 patients undergoing PV isolation with preprocedural CT-scanning, LCPV+ patients were selected with measurement of PV ostial area and trunk distance. All LCPV+ patients were matched between RF and CB-A group in a 1:1 ratio based on propensity scores, and compared for outcome. RESULTS: Left common pulmonary veins were found in 31% (88/283) RF versus 34% (146/433) CB-A patients, respectively, (P = .44). In the matched population of 83 LCPV+ patients in each group, electrical isolation could be achieved in all left-sided PVs. No significant difference was noted for the rate of AF/left atrial tachyarrhythmia (LAT) recurrence between RF and CB-A group (30% vs 28%, P = .86), with similar AF/LAT-free survival (log rank, P = .71). There were 48 patients with AF/LAT recurrence (29%) during the follow-up. Recurrence rate between paroxysmal versus persistent AF was 27/120 (22.5%) versus 21/46 (46%), P = .004. Cox proportional regression analysis withheld LA volume and persistent AF as independent variables to predict AF/LAT recurrence. No increased hazard for AF/LAT recurrence was observed for patients with a long (>15 mm) vs short (5-15 mm) LCPV trunk (OR 1.14, 95% CI 0.6-2.2, P = .7). CONCLUSIONS: In our study, equal efficacy and outcome was noted in LCPV+ patients between RF and CB-A technology.

Anatomic predictors of late right inferior pulmonary vein reconnection in the setting of second-generation cryoballoon ablation.

INTRODUCTION: The right inferior pulmonary vein (RIPV) accounts as the most frequently reconnected vein after pulmonary vein isolation using second-generation cryoballoon ablation (CB-A). Our objective was to assess anatomic predictors of late RIPV reconnection based on preprocedural computed tomography scan. METHODS: Patients with a repeat procedure for atrial tachyarrhythmia recurrence after index CB-A procedure were included. A total of 129 RIPVs were evaluated for ostial diameters, ostial area, and branching pattern. Interior angle between RIPV and horizontal line in the frontal/transversal plane was used to measure the RIPV orientation: RIPV frontal/transversal angle, respectively. In addition, interior angle between RIPV and the line perpendicular on the septal intersection line at the level of the fossa ovalis, estimated as trans-septal (TS) puncture site, was measured in the frontal/transversal view: RIPV-TS frontal/transversal angle, respectively. RESULTS: Late vein reconnection was present in 36/129 RIPVs (28%). Warmer balloon nadir temperature (P = .01), more inferior (P < .001) and posterior (P < .01) RIPV orientation (ie, more positive RIPV frontal and RIPV transversal angle, respectively), and sharper RIPV-TS frontal angle (P < .001) were associated with late RIPV reconnection on univariate analysis. Independent variables after multivariate analysis were nadir temperature (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.03-1.23; P = .013) and RIPV frontal angle (OR, 1.13, CI, 1.07-1.19; P < .001). CONCLUSION: Frontal RIPV orientation could significantly predict late RIPV electrical reconnection after CB-A. Therefore, preprocedural anatomic assessment of the RIPV might be useful to plan the correct ablation strategy.

Over-the-needle trans-septal access using the cryoballoon delivery sheath and dilator in atrial fibrillation ablation.

BACKGROUND: In the setting of second-generation cryoballoon (CB2) ablation, left atrial (LA) access is generally achieved using a standard sheath (SS) that is exchanged for the 15Fr cryoballoon delivery sheath (CBS) and dilator over a long wire (CBS over-the-wire technique, CBS-W). Our objective was to evaluate the direct use of the CBS to gain LA access, by advancing the latter over the trans-septal needle (CBS over-the-needle technique, CBS-N), under transesophageal echocardiographic (TEE) guidance. METHODS: Consecutive patients who underwent CB2 ablation with the CBS-N technique were evaluated for feasibility of gaining LA access using TEE guidance and fluoroscopy views. Complications related to the LA access were compared with a matched CBS-W control group. Subanalysis (30 CBS-W vs 30 CBS-N patients) evaluated time-to-LA of the CBS: time from superior vena cava (with SS vs CBS) to LA insertion of the CBS, after exchange or directly, respectively. RESULTS: LA access could be achieved in all 505 patients of the CBS-N group, without technique modification or additional equipment. Challenging interatrial septa were noted in 13% of these patients: previous atrial septal defect repair (1%), hypermobile (10%), aneurysmal (1%), and abnormally thickened/fibrotic (1%). Incidence of complications was similar to the CBS-W group. Subanalysis showed a shorter time-to-LA in the CBS-N versus CBS-W group, 72 ± 46 seconds versus 293 ± 180 seconds, P < .001. CONCLUSIONS: Our study showed that the CBS-N technique is feasible and safe under echocardiographic guidance. Without sheath exchange, it simplifies the CB2 procedure, is less costly, time sparing, and might reduce the risk of air embolism.

Impact of an additional right pulmonary vein on second-generation cryoballoon ablation for atrial fibrillation: a propensity matched score study.

PURPOSE: Cryoballoon (CB) technology in the context of anatomical pulmonary vein (PV) variants might hypothetically hamper successful PV isolation (PVI). Our aim was to assess the impact of a right middle PV (RMPV) in the setting of second-generation cryoballoon (CB advance-CB-A), on procedural parameters and on mid-term follow-up. METHODS: Consecutive patients with AF presenting RMPV (RMPV+) at the pre-procedural computed tomography who underwent PVI by CB-A were enrolled. Comparison with propensity score-matched patients without RMPV (RMPV-) was performed. Acute procedural parameters and clinical follow-up were assessed. RESULTS: A total of 240 patients (80 RMPV+) were included in the analysis. Twelve of 80 (15%) RMPV+ patients underwent a direct cryo-application in this variant and accomplished the isolation without phrenic nerve palsy, whereas in 25 of 80 (31%) RMPV+ patients, the RMPVs were not targeted directly nor indirectly (by co-occlusion during application at a major PV). At a median follow-up of 17.3 [interquartile range 11.3-26.5] months, there was no significant difference in AF-free survival between RMPV+ and RMPV- patients (78.8 vs 78.1%, P = 1.00), and the recurrence of atrial arrhythmias among patients with versus without an intentional or indirect cryo-application to the RMPV was not different (22 vs 20%, P = 1.00). CONCLUSIONS: Mid-term outcome after CB-A ablation did not differ between RMPV+ and RMPV- patients. Within RMPV+ patients, outcome was similar between those with versus without a cryo-application (either direct or indirect) to the additional vein.

Continuous monitoring after second-generation cryoballoon ablation for paroxysmal atrial fibrillation in patients with cardiac implantable electronic devices.

BACKGROUND: The second-generation cryoballoon (CB) is effective in achieving pulmonary vein isolation. Continuous monitoring would eliminate any over- or underestimated freedom from atrial fibrillation (AF) postablation. OBJECTIVE: The purpose of this study was to differentiate between arrhythmias occurring after cryoballoon ablation (CBA), detecting true AF in symptomatic patients and detecting silent subclinical AF. METHODS: Between June 2012 and January 2015, 54 patients with a preexisting cardiac implantable electronic device (CIED) who had undergone CBA for paroxysmal atrial fibrillation (PAF) were included in our retrospective study. Regular CIED controls, physical examination, and ECG recordings were performed by an experienced cardiologist blinded to the ablation procedure. Data on any hospitalization during follow-up were gathered. Patients were encouraged to note all clinical symptoms during follow-up. RESULTS: Continuous monitoring showed a success rate of 83.3% after 1 year and 75.93% after 3 years of follow-up. During the first year, 68% of episodes of palpitations after ablation were due to sinus tachycardia, nonsustained ventricular tachycardia, or supraventricular tachycardia. AF recurrence was detected in 15.6% of asymptomatic patients during follow-up. Total AF burden post-CBA had decreased to 0.64% ± 4.34% (P <.001) during long-term follow-up of 3.3 years. CONCLUSION: Although this is a selected group of patients with a preexisting CIED, continuous monitoring showed freedom from AF in 83.3% of patients post-CBA after 1 year and 75.93% after 3 years of follow-up.

Value of ultrasound for access guidance and detection of subclinical vascular complications in the setting of atrial fibrillation cryoballoon ablation.

AIMS: Vascular complications are the most common complications of atrial fibrillation (AF) ablation. Cryoballoon (CB) ablation for AF needs the insertion of a large 15 Fr sheath in the femoral vein. Our aim was to investigate the impact of vascular ultrasound (US) in guiding access and evaluating post-procedural subclinical complications in a large, multi-centre patient cohort that underwent CB ablation. METHODS AND RESULTS: A total cohort of 1435 consecutive patients were subdivided in 870 US -/-, 265 US -/+, and 300 US +/+ patients depending on US performance for: venipuncture guidance/post-procedural evaluation. Major clinical complications (requiring intervention and/or prolonged stay) were assessed. Irrespective of the clinical status, major US events were systematically determined in the subgroups with US evaluation 1 day post-procedure, if evidence of inadvertent artery puncture/cannulation (communication between artery and collection or artery-vein, regardless of the thrombosis state). Major clinical events were encountered in 1.7% (15/870), 1.1% (3/265), and 0% of patients in US -/-, US -/+, and US +/+ group, respectively (P = 0.02 between US -/- and US +/+ group). In the US -/- group, 5/10 (50%) of pseudo-aneurysms were diagnosed during readmission after a mean of 24 ± 11 days post-procedure. No delayed presentation was seen in the US -/+ group. Major US events during the US protocol post-procedure were seen in 3.8% (10/265) vs. 0.3% (1/300) of patients in US -/+ vs. US +/+ group, respectively, P = 0.004. CONCLUSION: US-guided venipuncture was associated with a near-to-zero risk of vascular complications in our patients undergoing CB ablation.

Second-Generation Cryoballoon Ablation for Atrial Fibrillation　- A Detailed Analysis of the Impact of Left Atrial Volume Index on Clinical Outcome.

BACKGROUND: Pulmonary vein isolation (PVI) by means of cryoballoon is increasingly being used for the treatment of atrial fibrillation (AF). This study assessed whether the left atrial volume index (LAVI) predicts AF recurrence following PVI by means of 2nd-generation cryoballoon (Cryoballoon Advance; CB-A) when comparing persistent AF (PeAF) and paroxysmal AF (PAF). Methods and Results: Patients with drug-resistant AF and undergoing preprocedural computed tomography (CT) and PVI with CB-A were included. LAV was estimated from 3D CT images. A total of 417 patients with AF were included (95 PeAF, 322 PAF patients). After a mean of 22.1±9.4 months follow-up, 45/95 (47%) PeAF patients and 254/322 (79%) PAF patients had no recurrence. LAVI was an independent predictor for AF recurrence in PeAF patients (hazard ratio 1.042 per 1 mL/m2; 95% confidence interval 1.006-1.080, P=0.02), but not in PAF patients. In PeAF patients with LAVI ≤61 mL/m2, the freedom from recurrence was 78.5% vs. 22.2% in those with LAVI >61 mL/m2 (hazard ratio 5.771, 95% confidence interval 2.434-13.682, P<0.001), and the mid-term success rate was comparable with PAF patients. CONCLUSIONS: LAVI predicted AF recurrence after PVI using CB-A in PeAF patients but not in PAF patients. If LAVI was ≤61 mL/m2, the mid-term efficacy among PeAF patients was equivalent to that for PAF patients.

Real-Time Recordings in Cryoballoon Pulmonary Veins Isolation: Comparison Between the 25mm and the 20mm Achieve Catheters.

AIMS: Real Time Recordings (RTR) of pulmonary vein (PV) activity provide important information in the setting of the 2nd generation Cryoballoon (CB-A), as a funcion of time to isolation. Visualization of RTR with the standard inner lumen mapping catheter (ILMC) 20mm Achieve (AC) is possible in roughly 50% of PVs. A novel 25mm-Achieve Advance (AC-A) has been developed with the aim of increasing the detection of RTR. The purpose of this study is to compare the AC-A with the AC, to feasibility and improvement of RTR. METHODS: We assigned 50 patients with paroxysmal or persistent atrial fibrillation to CB-A PVI, using the AC-A as ILMC. We compared this group with 50 patients, matched for age and left atrial volume, who previously underwent the CB-A PVI using the AC. RESULTS: RTR were more frequently observed with the AC-A than with the AC (74% vs 49%; p= 0.02). RTR in the left superior PVs was similar in both groups (74% vs 72%, p= 0.8). RTR with the AC-A were equally appreciated in left or right sided, superior or inferior PVs. No significant differences were found in terms of feasibility, procedure fluoroscopy and freezing times, nadir temperatures, and acute PVI. CONCLUSIONS: CB-A PVI with the AC-A is feasible and safe in all PVs. The AC-A has proven significantly superior in visualising RTR if compared to the AC, affording RTR in 74% of PVs.

Anatomical and procedural predictors of pulmonary vein stenosis in the setting of second-generation cryoballoon ablation.

AIMS: Pulmonary vein stenosis (PVS) is a well recognized complication as a consequence of pulmonary vein isolation. In the current study, we sought to analyze potential anatomical and intraprocedural predictors of PVS during second-generation cryoballoon ablation, particularly focusing on the impact of freeze duration and number of cryoapplications. METHODS: Fifty-four patients who underwent cryoballoon ablation for atrial fibrillation were included retrospectively in this study. All patients underwent cardiac-enhanced multidetector computed tomography both before and after the ablation. The exclusion criteria were any contraindications for the procedure, including the presence of an intracavitary thrombus, uncontrolled heart failure and contraindications to general anesthesia. RESULTS: Mild (25-50%) PVS was only detected in one vein (0.4%) and neither moderate (50-75%) nor severe (>75%) PVS were found. Twenty-five pulmonary veins (12%) exhibited slight narrowing of the diameter (less than 25%). In the univariate analysis, a longer duration of cryoapplication and a larger pulmonary vein ostium preprocedure diameter and area were independently associated with pulmonary vein narrowing [odds ratio (OR): 1.004; confidence interval (CI): 1.001-1.008, P = 0.016; OR: 1.250, CI: 1.090-1.434, P = 0.001 and OR: 1.006; CI: 1.002-1.011, P = 0.006] respectively. CONCLUSION: Longer duration of cryoablation, an increased number of applications per vein and larger pulmonary vein ostia are associated with a higher risk of pulmonary vein diameter and area reduction. These findings might suggest to lower the dosing to a single and shorter application if isolation is attained, to reduce the possibility of future pulmonary vein narrowing.

Acute pericarditis following second-generation cryoballoon ablation for atrial fibrillation.

PURPOSE: Acute pericarditis is a minor complication following atrial fibrillation (AF) ablation procedures. The aim of the study was to evaluate the incidence and clinical aspects of pericarditis following cryoballoon (CB) ablation of AF investigating a possible association with procedural characteristics and a possible relationship with post-ablation recurrences. METHODS: Four hundred fifty consecutive patients (male 73%, age 59.9 ± 11.2 years) with drug-resistant paroxysmal AF who underwent CB ablation as index procedure were enrolled. Exclusion criteria were any contraindication for the procedure including the presence of intracavitary thrombus and uncontrolled heart failure and contraindications to general anesthesia. RESULTS: Acute pericarditis following CB ablation occurred in 18 patients (4%) of our study population. Pericardial effusion occurred in 14 patients (78%) and was mild/moderate. The total number of cryoapplications and the total freeze duration were significantly higher in patients with pericarditis compared with those without (respectively, p = 0.0006 and p = 0.01). Specifically, the number of applications and freeze duration in right inferior pulmonary vein were found significantly higher in patients with pericarditis (p = 0.007). The recurrence rate did not significantly differ between the two study groups (respectively, 16.7 vs 18.1%; p = 0.9). CONCLUSIONS: The incidence of acute pericarditis following CB ablation in our study population accounted for 4% and was associated with both total freezing time and number of cryoapplications. The clinical course was favorable in all these patients and the occurrence of acute pericarditis did not affect the outcome during the follow-up period.

Long-term outcome of pulmonary vein isolation in patients with paroxysmal atrial fibrillation and Brugada syndrome.

Aims: The therapeutical management of atrial fibrillation (AF) in the setting of Brugada syndrome (BS) might be challenging as many antiarrhythmic drugs (AADs) with sodium channel blocking properties might lead to to the development of ventricular arrhythmias. This study sought to evaluate the clinical outcome in a consecutive series of patients with BS having undergone pulmonary vein (PV) isolation by means of radiofrequency (RF) or cryoballoon (CB) ablation and the efficacy of catheter ablation for preventing inappropriate interventions delivered by implantable cardioverter defibrillators (ICD) on a 3-year follow up. Methods and results: Twenty-three consecutive patients with BS (13 males; mean age was 47 ± 18 years) having undergone PV isolation for drug-resistant paroxysmal AF were enrolled. Eleven patients (48%) had an ICD implanted of whom four had inappropriate shocks secondary to rapid AF. Over a mean follow-up period of 35.0 ± 25.4 months (median 36 months) the freedom from AF recurrence after the index PV isolation procedure was 74% without AADs. Patients with inappropriate ICD interventions for AF did not present futher ICD shocks after AF ablation. No major complications occurred. Conclusion: Catheter ablation is a valid therapeutic choice for patients with BS and paroxysmal AF considering the high success rates, the limitations of the AADs and the safety of the procedure, and it should be taken into consideration especially in those patients presenting inappropriate ICD shocks due to rapid AF.

Second generation cryoballoon ablation for atrial fibrillation in young adults: midterm outcome in patients under 40 years of age.

Aims: Pulmonary vein isolation (PVI) has been demonstrated more effective in young patients, in which the substrate for atrial fibrillation (AF) is probably more confined to pulmonary vein potentials. The present study sought to focus on the midterm outcomes in patients under 40 years having undergone PVI with the Cryoballoon Advance because of drug resistant AF. Methods and results: Between June 2012 and December 2015, 57 patients having undergone Cryoballoon ablation (CB-A) below 40 years of age for AF in our centre were retrospectively analysed and considered for our analysis. All patients underwent this procedure with the 28 mm Cryoballon Advance. All 227 veins were successfully isolated without the need for additional focal tip ablation. Median follow-up was 18 ±10 months. The freedom from AF after a blanking period of 3 months was 88% in our cohort of patients younger than 40 years old. The most frequent periprocedural complication was related to the groin puncture and occurred in 2 patients. After a single procedure, the only univariate predictor of clinical recurrence was the diagnosis of hypertrophic cardiomyopathy. Conclusion: Young patients affected by AF can be effectively and safely treated with CB-A that grants freedom from AF in 88% of the patients at 18 months follow-up following a 3-month blanking period. All veins could be isolated with the large 28 mm Cryoballoon Advance only.

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.

Single freeze per vein strategy with the second-generation cryoballoon for atrial fibrillation: a propensity score-matched study between 180- and 240-s application time in a large cohort of patients.

Aims: The single-freeze strategy using the second-generation cryoballoon (CB-A, Arctic Front Advance, Medtronic, Minneapolis, MN, USA) has been reported to be as effective as the recommended double-freeze approach in several single-centre studies. In this retrospective, international, multicentre study, we compare the 3-min single-freeze strategy with the 4-min single-freeze strategy. Methods and results: Four hundred and thirty-two patients having undergone pulmonary vein isolation (PVI) by means of CB-A using a single-freeze strategy were considered for this analysis. A cohort of patients who were treated with a 3-min strategy (Group 1) was compared with a propensity score-matched cohort of patients who underwent a 4-min strategy (Group 2). Pulmonary vein isolation was successfully achieved in all the veins using the 28-mm CB-A. The procedural and fluoroscopy times were lower in Group 1 (67.8 ± 17 vs. 73.8 ± 26.3, P < 0.05; 14.9 ± 7.8 vs. 24.2 ± 10.6 min, P < 0.05). The most frequent complication was PNP, with no difference between the two groups (P = 0.67). After a mean follow-up of 13 ± 8 months, taking into consideration a blanking period of 3 months, 85.6% of patients in Group 1 and 87% of patients in Group 2 were free from arrhythmia recurrence at final follow-up (P = 0.67). Conclusion: There is no difference in acute success, rate of complications, and freedom from atrial fibrillation recurrences during the follow-up between 3-min and 4-min per vein freeze strategies. The procedural and fluoroscopy times were significantly shorter in 3-min per vein strategy.

Phrenic nerve injury during right inferior pulmonary vein ablation with the second-generation cryoballoon: clinical, procedural, and anatomical characteristics.

Aims: There is still sparse information regarding phrenic nerve injury (PNI) during ablation of the right inferior pulmonary vein (RIPV) by means of the second-generation cryoballoon advance (CB-A). The aim of this study was to describe the procedural, anatomical, and clinical characteristics of patients who experienced PNI during the RIPV ablation. Methods and results: Consecutive patients who had undergone pulmonary vein isolation (PVI) using CB-A and suffered PNI during RIPV ablation were retrospectively included in our study. A cohort of patients who did not suffer any PNI was randomly included in a 1:3 ratio as a control group. The incidence of PNI during RIPV cryoapplication was 3.5%, (34 of 979 patients). There were no significant differences in clinical characteristics between patients with and without PNI. The prevalence of right common ostium (RCO) was significantly higher in patients with a PNI [4 patients (11.8%) vs. 1 patient (1.0%); P < 0.01]. A temperature drop velocity from the basal temperature to - 20 °C of 2.38 °C/s rendered a sensitivity of 82.4% and a specificity of 51.0% with a negative predictive value of 89.7%. Temperature drop velocity from basal to - 20 °C and the presence of an RCO were predictors of PNI in the multivariate analysis [odds ratio (OR) 7.27, 95% confidence interval (CI) 2.54-20.80; P < 0.01 and OR 18.41, 95%CI 1.87-181.23; P = 0.01, respectively). Conclusion: PNI during RIPV freeze might occur in around 3.5% of cases. The presence of an RCO and a fast temperature drop must prompt a careful monitoring of the phrenic nerve function during cryoapplications on the RIPV.

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.

Role of the burden of premature atrial contractions during the blanking period following second-generation cryoballoon ablation in predicting late recurrences of atrial arrhythmias.

PURPOSE: Recent data suggests that high burden of premature atrial complexes after pulmonary vein isolation predicts recurrences of atrial arrhythmias. The present study sought to assess the role of premature atrial complexes burden in predicting atrial arrhythmias recurrences in patients with atrial fibrillation (AF) who have undergone second-generation cryoballoon ablation (CB-Adv). METHODS: Consecutive patients with drug-resistant paroxysmal atrial fibrillation who underwent pulmonary vein isolation using CB-Adv technology as the index procedure were retrospectively included. Twenty-four-hour Holter recordings were performed for every patient. Based on previously published data, a burden of more than 76 premature atrial complexes per day was considered as being high. RESULTS: One hundred and seven patients were included in the analysis. The recurrence rate among the group of patients with more than 76 premature atrial complexes per day was significantly higher compared with the group with a lower burden of premature atrial complexes (47.5 vs 11.9%, respectively; p < 0.001). In the multivariate analysis, the documentation of more than 76 premature atrial complexes per day registered at 1 month and at the end of the blanking period, predicted late recurrence of atrial arrhythmias. CONCLUSIONS: Frequent premature atrial complexes in the early stages after CB-Adv ablation strongly predict late recurrences of atrial arrhythmias.

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.

Single freeze strategy with the second- generation cryballoon for atrial fibrillation: a multicenter international retrospective analysis in a large cohort of patients.

PURPOSE: The second-generation cryoballoon (CB-A, Arctic Front Advance, Medtronic, Minneapolis, MN, USA) has proven to be highly effective in achieving freedom from atrial fibrillation; nonetheless, the ideal number and duration of freezing cycles is still a matter of debate. We investigated the acute success, procedural complications, and clinical outcome of a single freeze strategy using the CB-A in a large, retrospective, international multicenter study. METHODS: Between January 2013 and September 2015, 818 consecutive patients (58 ± 12 years, 68% males) with drug-resistant atrial fibrillation (AF) who underwent a CB-A using a single freeze strategy were taken into consideration for our analysis. RESULTS: Paroxysmal AF was documented in 74.1% of the patients, while 25.9% presented with persistent AF. Additional freezes were needed in a mean 1.4 veins per patient. 0.2% of the patients experienced persistent PNP that was still documented at the last follow-up. After a median follow-up of 14 ± 8 months, taking into consideration a blanking period (BP) of 3 months, 692 patients (84.6%) were free from arrhythmia recurrence. After a single procedure, AF recurrence during BP and persistent AF were identified as predictors of clinical recurrence after BP. CONCLUSIONS: Single freeze CB-A ablation is effective in treating drug-resistant AF and affords freedom from arrhythmia recurrences in 84.6% of patients during a 14-month follow-up. Persistent AF and recurrence during BP are predictors of arrhythmia recurrences.