Pulsed-field versus cryoballoon ablation for atrial fibrillation-Impact of energy source on sedation and analgesia requirement.

INTRODUCTION: Pulsed field ablation (PFA) represents a novel, nonthermal energy modality that can be applied for single-shot pulmonary vein isolation (PVI) in atrial fibrillation (AF). Comparative data with regard to deep sedation to established single-shot modalities such as cryoballoon (CB) ablation are scarce. The aim of this study was to compare a deep sedation protocol in patients receiving PVI with either PFA or CB. METHODS: Prospective, consecutive AF patients undergoing PVI with a pentaspline PFA catheter were compared to a retrospective CB-PVI cohort of the same timeframe. Study endpoints were the requirements of analgesics, cardiorespiratory stability, and sedation-associated complications. RESULTS: A total of 100 PVI patients were included (PFA n = 50, CB n = 50, mean age 66 ± 10.6, 61% male patients, 65% paroxysmal AF). Requirement of propofol, midazolam, and sufentanyl was significantly higher in the PFA group compared to CB [propofol 0.14 ± 0.04 mg/kg/min in PFA vs. 0.11 ± 0.04 mg/kg/min in CB (p = .001); midazolam 0.00086 ± 0.0004 mg/kg/min in PFA vs. 0.0006295 ± 0.0003 mg/kg/min in CB (p = .002) and sufentanyl 0.0013 ± 0.0007 µg/kg/min in PFA vs. 0.0008 ± 0.0004 µg/kg/min in CB (p < .0001)]. Sedation-associated complications did not differ between both groups (PFA n = 1/50 mild aspiration pneumonia, CB n = 0/50, p > .99). Nonsedation-associated complications (PFA: n = 2/50, 4%, CB: n = 1/50, 2%, p > .99) and procedure times (PFA 75 ± 31, CB 84 ± 32 min, p = .18) did not differ between groups. CONCLUSIONS: PFA is associated with higher sedation and especially analgesia requirements. However, the safety of deep sedation does not differ to CB ablation.

A worldwide survey on incidence, management, and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: the POTTER-AF study.

AIMS: Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management, and outcome are sparse. METHODS AND RESULTS: This international multicentre registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553 729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed, at 214 centres in 35 countries. In 78 centres 138 patients [0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (P < 0.0001)] were diagnosed with an oesophageal fistula. Peri-procedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8% and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) [odds ratio 7.463 (2.414, 23.072) P < 0.001]. CONCLUSION: Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high.

High In-Hospital Mortality in SARS-CoV-2-Infected Patients with Active Cancer Disease during Omicron Phase of the Pandemic: Insights from the CORONA Germany Study.

INTRODUCTION: SARS-CoV-2 infected patients with cancer have a worse outcome including a significant higher mortality, compared to non-cancer patients. However, limited data are available regarding in-hospital mortality during the Omicron phase of the pandemic. Therefore, the aim of the study was the comparison of mortality in patients with history of cancer and patients with active cancer disease during the different phases of the COVID-19 pandemic, focusing on the current Omicron variant of concern. METHODS: We conducted a multicenter, observational, epidemiological cohort study at 45 hospitals in Germany. Until July 20, 2022, all adult hospitalized SARS-CoV-2 positive patients were included. The primary endpoint was in-hospital mortality regarding cancer status (history of cancer and active cancer disease) and SARS-CoV-2 virus type. RESULTS: From March 11, 2020, to July 20, 2022, a total of 27,490 adult SARS-CoV-2 positive patients were included in the study. 2,578 patients (9.4%) had diagnosis of cancer, of whom 1,065 (41.3%) had history of cancer, whereas 1,513 (58.7%) had active cancer disease. Overall 3,749 out of the total of 27,490 patients (13.6%) died during the hospital stay. Patients with active cancer disease had a significantly higher mortality compared to patients without cancer diagnosis, in both phases of the pandemic (wild-type to Delta: OR 1.940 [1.646-2.285]); Omicron: 2.864 [2.354-3.486]). After adjustment to co-variables, SARS-CoV-2 infected patients with active cancer disease had the highest risk for in-hospital mortality compared to the other groups, in both phases of the pandemic. CONCLUSION: The CORONA Germany study indicates that hospitalized patients with active cancer disease are at high risk of death during a SARS-CoV-2 infection. Mortality of patients with history of cancer improved to nearly the level of non-cancer patients during Omicron phase.

A Simplified Approach to Pulmonary Vein Visualization during Cryoballoon Ablation of Atrial Fibrillation.

Background and Objectives: Selective pulmonary vein (PV) angiography has been established as the gold standard for PV visualization in cryoballoon (CB)-based pulmonary vein isolation (PVI). We sought to simplify this approach to reduce procedural complexity and radiation exposure. Materials and Methods: Patients with paroxysmal and recently diagnosed persistent AF undergoing CB-based PVI from January 2015 to December 2017 were retrospectively analyzed. Patients underwent either selective PV angiography or conventional left atrial (LA) angiography for PV visualization. Results: A total of 336 patients were analyzed. A total of 87 patients (26%) received PV angiography and 249 (74%) LA angiography. LA angiography required fewer cine-sequences for PV visualization, translating into a significant reduction in procedure duration, fluoroscopy time and dose area product. Additionally, less contrast medium was utilized. PV occlusion by the CB, CB temperature and time to isolation showed no significant differences. The number of CB applications and total application time (LA angiography: 1.4 ± 0.02 vs. PV Angiography: 1.6 ± 0.05; p < 0.0001; LA angiography: 297.9 ± 4.62 vs. PV-Angiography: 348.9 ± 11.03; p < 0.001, respectively) per vein were slightly but significantly higher in the PV angiography group. We observed no difference in late AF recurrence (24.7% LA angiography vs. 21.3% PV angiography; p = 0.2657). Conclusions: A simplified protocol, using LA angiography for PV visualization, entails a reduction in procedure time and radiation exposure while equally maintaining procedural efficiency and safety in both groups.

Sleep apnea predicts cardiovascular death in patients with Marfan syndrome: a cohort study.

Background: Surgical replacement of the aortic root is the only intervention that can prevent aortic dissection and cardiovascular death in Marfan syndrome (MFS). However, in some individuals, MFS also causes sleep apnea. If sleep apnea predicts cardiovascular death, a new target for predictive, preventive, and personalized medicine (PPPM) may emerge for those individuals with MFS who have sleep apnea. Methods: This is an investigator-initiated study with long-term follow-up data of 105 individuals with MFS. All individuals were screened for sleep apnea regardless of symptoms. Cardiovascular death served as a primary endpoint, and aortic events as a secondary outcome. Results: Sleep apnea with an apnea-hypopnea index (AHI) > 5/h was observed in 21.0% (22/105) with mild sleep apnea in 13% (14/105) and moderate to severe sleep apnea in 7.6% (8/105). After a median follow-up of 7.76 years (interquartile range: 6.84, 8.41), 10% (10/105) had died, with cardiovascular cause of death in 80% (8/10). After adjusting for age and body mass index (BMI), the AHI score emerged as an independent risk factor for cardiovascular death (hazard ratio 1.712, 95% confidence interval [1.061-2.761], p = 0.0276). The secondary outcome of aortic events occurred in 33% (35/105). There was no effect of the AHI score on aortic events after adjusting for age and BMI (hazard ratio 0.965, 95% confidence interval [0.617-1.509]), possibly due to a high number of patients with prior aortic surgery. Interpretation: Sleep apnea is emerging as an independent predictor of cardiovascular death in MFS. It seems mandatory to screen all individuals with MFS for sleep apnea and to include these individuals, with both MFS and sleep apnea, in further studies to evaluate the impact of preventive measures with regard to cardiovascular death. Supplementary Information: The online version contains supplementary material available at 10.1007/s13167-022-00291-4.

Outcome after tailored catheter ablation of atrial tachycardia using ultra-high-density mapping.

INTRODUCTION: Tailored catheter ablation of atrial tachycardias (ATs) is increasingly recommended as a potentially easy treatment strategy in the era of high-density mapping (HDM). As follow-up data are sparse, we here report outcomes after HDM-guided ablation of ATs in patients with prior catheter ablation or cardiac surgery. METHODS AND RESULTS: In 250 consecutive patients (age 66.5 ± 0.7 years, 58% male) with ATs (98% prior catheter ablation, 13% prior cardiac surgery) an HDM-guided catheter ablation was performed with the support of a 64-electrode mini-basket catheter. A total of 354 ATs (1.4 ± 0.1 ATs per patient; mean cycle length 304 ± 4.3 ms; 64% macroreentry, 27% localized reentry, and 9% focal) with acute termination of 95% were targeted in the index procedure. A similar AT as in the index procedure recurred in five patients (2%) after a median follow-up time of 535 days (interquartile range (IQR) 25th-75th percentile: 217-841). Tailored ablation of reentry ATs with freedom from any arrhythmia was obtained in 53% after a single procedure and in 73% after 1.4 ± 0.4 ablation procedures (range: 1-4). A total of 228 patients (91%) were free from any arrhythmia recurrence after 210 days (IQR: 152-494) when including optimal usual care. CONCLUSIONS: Tailored catheter ablation of ATs guided by HDM has a high acute success rate. The recurrence rate of the index AT is low. In patients with extensive atrial scaring further ablation procedures need to be considered to achieve freedom from any arrhythmia.

Contemporary analysis of phrenic nerve injuries following cryoballoon-based pulmonary vein isolation: A single-centre experience with the systematic use of compound motor action potential monitoring.

BACKGROUND: Phrenic nerve injury (PNI) remains one of the most frequent complications during cryoballoon-based pulmonary vein isolation (CB-PVI). Since its introduction in 2013, the use of compound motor action potential (CMAP) for the prevention of PNI during CB-PVI is increasing; however, systematic outcome data are sparse. METHODS: The CMAP technique was applied in conjunction with abdominal palpation during pacing manoeuvres (10 mV, 2 ms) from the superior vena cava for 388 consecutive patients undergoing CB-PVI between January 2015 and May 2017 at our tertiary arrhythmia centre. Cryoablation was immediately terminated when CMAP amplitude was reduced by 30%. RESULTS: Reductions in CMAP amplitude were observed in 16 (4%) of 388 patients during isolation of the right veins. Of these, 11 (69%) patients did not manifest a reduction in diaphragmatic excursions. The drop in CMAP amplitude was observed in 10 (63%) patients during ablation of the right superior pulmonary veins (PVs) and in 7 (44%) patients during ablation of the right inferior PVs. Postprocedural persistent PNI was observed in three of four patients for a duration of 6 months, with one of these patients remaining symptomatic at the 24-month follow-up. One of the four patients was lost to long-term follow-up. CONCLUSIONS: All PNIs occurred during right-sided CB-PVI and were preceded by a reduction in CMAP amplitude. Thus, the standardized use of CMAP surveillance during CB-PVI is easily applicable, reliable and compared with other studies, results in a lower number of PNIs.

Ultra-high-density mapping of conduction gaps and atrial tachycardias: Distinctive patterns following pulmonary vein isolation with cryoballoon or contact-force-guided radiofrequency current.

INTRODUCTION: The aim of this study was to investigate electrophysiological findings in patients with arrhythmia recurrence undergoing a repeat ablation procedure using ultra-high-density (UHDx) mapping following an index procedure using either contact-force (CF)-guided radiofrequency current (RFC) pulmonary vein isolation (PVI) or second-generation cryoballoon (CB) PVI for treatment of atrial fibrillation (AF). METHODS AND RESULTS: Fifty consecutive patients with recurrence of AF and/or atrial tachycardia (AT) following index CF-RFC PVI (n = 21) or CB PVI (n = 29) were included. A 64-pole mini-basket mapping catheter in combination with an UHDx-mapping system-guided ablation was used. RFC was applied using a catheter tip with three incorporated mini-electrodes. PV reconnection rates were higher after CF-RFC PVI (CF-RFC: 2.5 ± 1.3 PVs vs CB: 1.4 ± 0.9 PVs; P = .0025) and left PVs were more frequently reconnected (CF-RFC: 64% PVs vs CB: 35% PVs; P = .0077). Fractionated signals along the antral index ablation line (FS) were found in 30% of CB-PVI patients (CF-RFC: 9.5% vs CB:30%; P = .098) targeted for ablation. In five cases, FS were a critical part of maintaining consecutive AT. The main AT mechanism found during reablation (n = 45 ATs) was macroreentry (80% [36/45], CF-RFC: 78.9% vs CB: 80.8%; P = 1.0) with a variety of circuits throughout both atria. CONCLUSION: UHDx mapping is sensitive in detecting conduction gaps along the index ablation line. Left PVs are more frequently reconnected after initial CF-RFC PVI. FS are a common finding after CB PVI and can maintain certain forms of ATs. ATs after index PVI are mostly macroreentries with a broad spectrum of entities.

Influence of energy source on early atrial fibrillation recurrences: a comparison of cryoballoon vs. radiofrequency current energy ablation with the endpoint of unexcitability in pulmonary vein isolation.

Introduction: Comparative data of early recurrence rates of atrial fibrillation (ERAF) following second-generation cryoballoon (CB-G2) and radiofrequency current (RFC) ablation for pulmonary vein isolation (PVI) in paroxysmal AF (PAF) are rare. We randomized PAF patients into either PVI with CB-G2 (group 1) or PVI with a combined RFC-approach applying contact force (CF) with the endpoint of unexcitability (group 2) to investigate ERAF. Methods and results: In group 1 (n = 30), CB-G2-PVI was performed. After CF-PVI in group 2 (n = 30), bipolar pacing on the ablation line and additional ablation until unexcitability was conducted. Follow-up included 48 h of in-hospital monitoring followed by 5-day Holter ECGs 1, 2, 3, 6, 12 months postablation to evaluate ERAF. Acute PVI was reached in 100% of group 2 and in 99% of group 1. Shorter procedure durations (98.0 ± 21.9 vs. 114.3 ± 18.7 min, P < 0.05) but extended fluoroscopy times (15.4 ± 3.9 vs. 10.0 ± 4.3 min, P < 0.05) were found in the CB-G2 group. Ten non-severe complications occurred (6 vs. 4 in group 1 and 2, P = 0.73). In group 2, five patients suffered from ERAF vs. seven patients in group 1 (P = 0.67). The time until the occurrence of ERAF was shorter in group 2 (1 day (q1-q3: 1-4.5)) when compared with group 1 (22 (q1-q3: 6-54) days, P = 0.025). Conclusion: ERAF rates were equal among groups; however, they occurred earlier in the initial phase after RFC ablation when compared with CB-G2. PVI utilizing cryoablation is associated with shorter procedure durations but extended fluoroscopy time while being similarly secure.

Improved 1-year clinical success rate of pulmonary vein isolation with the second-generation cryoballoon in patients with paroxysmal atrial fibrillation.

BACKGROUND: The second-generation cryoballoon (CB2) has recently been introduced featuring improved surface cooling. Increased procedural efficacy of pulmonary vein isolation (PVI) when compared to the first-generation balloon (CB1) has been reported. The aim of the study was to investigate the clinical outcome of cryoballoon PVI after 1 year using the CB2 as compared to the CB1. METHODS AND RESULTS: A total of 105 consecutive patients with paroxysmal atrial fibrillation (AF) were studied. Cryoballoon PVI (28 mm) was performed in 50 patients using the CB1, and in 55 patients using the CB2. Patients were scheduled for 72-hour Holter ECG recording at 3, 6, 9, and 12 months and every 6 months thereafter. The study endpoint was defined as recurrent AF or atrial tachycardia >30 seconds documented after a blanking period of 90 days after the procedure. Complete PVI was achieved in 49/50 (98%) and 55/55 (100%) patients in the CB1 and CB2 group, respectively. After a mean follow-up of 416 ± 75 days, 21 (CB1 group) and 10 (CB2 group) patients reached the study endpoint. Kaplan-Meier estimates of arrhythmia-free survival after a single procedure without AAD therapy after 1 year were 63.9% versus 83.6% (P = 0.008) in the CB1 and CB2 group, respectively. Persistent phrenic nerve palsy with delayed healing occurred in 2 (CB1 group) and 3 (CB2 group) patients. CONCLUSION: Clinical outcome of PVI using the CB2 was significantly improved when compared to the CB1.

Improved lesion formation using the novel 28 mm cryoballoon in atrial fibrillation ablation: analysis of biomarker release.

AIMS: Recently, a novel second-generation (G2) cryoballoon (CB) was introduced. Comparative analysis of lesion formation in terms of myocardial biomarker release [first-generation CB (G1) vs. G2] has not been studied. To compare myocardial biomarker release using the 28 mm G1 vs. G2 CB. METHODS AND RESULTS: In patients (patients) treated with the simplified single big CB (SBCB) strategy for pulmonary vein isolation (PVI), myocardial biomarkers [troponin T (TnT), creatine kinase, lactic dehydrogenase (LDH)] were measured at 12, 24, and 48 h after PVI. Two groups were defined: Group 1 (G1; freezing time: 300 s), Group 2 (G2; freezing time: 240 s). Mean biomarker peak values were compared. To correct for between-group differences in cumulative freezing time, an index calculated as peak biomarker release divided by cumulative freezing time was calculated. Sixty-six CB PVI procedures (G1: 33 patients, G2: 33 patients) were analysed. Pulmonary vein isolation was achieved in all the patients using the simplified SBCB technique only. Mean freezing time (51 ± 10 vs. 33 ± 6 min, P < 0.01) was significantly shorter in G2. All biomarker levels tended to be higher in G2 vs. G1. The indexed biomarkers values were significantly higher in G2: TnT: 18.8 ± 8.5 vs. 32.3 ± 13.6 pg/L/min (P < 0.01); creatinephosphokinase: 6.7 ± 2.7 vs. 11.7 ± 3.9 U/L/min (P < 0.01); LDH: 5.2 ± 1.0 vs. 9.1 ± 2.7 U/L/min (P < 0.01). On a 6-month follow-up (180 days), G2 revealed a significantly higher success rate (20/33 vs. 28/33; P = 0.027). CONCLUSION: Pulmonary vein isolation using the G2 CB increased the myocardial biomarker release index and is linked to a significantly improved 6 months success rate.

Comparison of balloon catheter ablation technologies for pulmonary vein isolation: the laser versus cryo study.

INTRODUCTION: Balloon catheters have been developed to facilitate pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF). We sought to compare the safety and efficacy of the cryoballoon (CB) and the laserballoon (LB) in a pilot study. METHODS AND RESULTS: One hundred and forty patients with drug-refractory PAF were prospectively allocated in a 1:1 fashion to undergo a PVI procedure with the 28 mm CB or the LB and were followed for 12 months using 3-day Holter ECG recording. The primary efficacy endpoint was a documented AF recurrence ≥ 30 seconds between 90 and 365 days after the index ablation. In total, 269 of 270 PVs (99.6%) and 270 of 273 PVs (98.9%) were acutely isolated in the CB and LB group, respectively. Mean procedural time was 136 ± 30 minutes for the CB group and 144 ± 33 minutes for the LB group (P = 0.13). Mean fluoroscopy time was longer in the CB group (21 ± 9 minutes vs 15 ± 6 minutes; P < 0.001). During 12 months follow-up, 37% of patients in the CB group and 27% in the LB group experienced an AF recurrence (P = 0.18). Phrenic nerve palsies occurred in 5.7% (CB) and 4.2% (LB) of patients, respectively. CONCLUSION: Balloon catheters are a viable option to safely perform a PVI procedure in patients with drug-refractory PAF. Ninety-nine percent of PVs may be acutely isolated with a single balloon catheter. The AF free survival rate after a single ablation procedure was not statistically different between groups.

A prospective randomized single-center study on the risk of asymptomatic cerebral lesions comparing irrigated radiofrequency current ablation with the cryoballoon and the laser balloon.

BACKGROUND: Asymptomatic cerebral lesions (ACL) may occur during atrial fibrillation (AF) ablation. We sought to compare the ACL incidence between 3 contemporary technologies: (1) irrigated radiofrequency current (RFC), (2) the single big cryoballoon (CB), and (3) the endoscopic laser-balloon (LB) in a prospective randomized pilot study. METHODS AND RESULTS: Ninety-nine patients were treated in 3 groups. Diffusion weighted MRI was acquired pre- (n = 20) and 24-48 h postablation (n = 99). After ablation, new ACL were detected in 22% of patients without significant differences between groups (RFC 8/33; CB 6/33; LB 8/33; P = 0.8). The presence of hypertension was identified as the only independent predictor of ACL by univariate regression analysis. During LB ablation, more ablation lesions (140 ± 19 vs 119 ± 18; P = 0.007) were applied during longer procedures (166 ± 36 vs 143 ± 32 min; P = 0.05) in patients with ACL. Univariate analysis revealed that a higher number of ablation lesions predicted ACL (P = 0.02). CONCLUSION: In this prospective, randomized, single-center pilot study, ablation technology did not influence the occurrence of ACL during AF ablation.

Endoscopic ablation systems.

Pulmonary vein (PV) isolation for ablation of atrial fibrillation is a well-accepted therapy option for high symptomatic patients refractory to antiarrhythmic drugs. Radiofrequency point-by-point ablation is the gold-standard technique; however, in the last two decades, many new technologies have been developed. The endoscopic ablation system makes direct PV ostium visualization possible, despite the large anatomy variation thanks to its compliant balloon. The laser generator delivers precise lesions that in the first clinical studies seem to be durable, with a safety and efficacy profile similar to the other PV isolation techniques. If these early results are confirmed by larger clinical studies, the endoscopic ablation system will offer a new paradigm in ablation of cardiac arrhythmias by directly visualizing the target substrate.

Improved procedural efficacy of pulmonary vein isolation using the novel second-generation cryoballoon.

INTRODUCTION: The cryoballoon technology has the potential to isolate a pulmonary vein (PV) with a single energy application. However, using the first-generation cryoballoon (CB-1G) repeated freezing or additional focal ablation is often necessary. The novel second-generation cryoballoon (CB-2G) features a widened zone of optimal cooling comprising the whole frontal hemisphere. The aim of this study was to investigate the impact of the novel design on procedural efficacy of cryoballoon PV isolation (CB-PVI). METHODS AND RESULTS: Single transseptal CB-PVI using an endoluminal spiral mapping catheter was performed in 60 consecutive patients (CB-1G, 28 mm, 300 seconds application time: 30 patients; CB-2G, 28 mm, 240 seconds application time: 30 patients). When compared to the CB-1G, using the CB-2G increased single-shot PVI rate from 51% to 84% (P < 0.001) and decreased procedure duration (128 ± 27 vs 98 ± 30 minutes; P < 0.001), and fluoroscopy exposure time (19.5 ± 7.4 vs 13.4 ± 5.3 min; P = 0.001). Effective CB-2G PVI could be performed with increased real-time PVI visualization rate (49% vs 76%; P < 0.001). Time to PVI (T(PVI)) was shorter in the CB-2G group (79 ± 60 vs. 52 ± 36 seconds; P = 0.049). Procedure-related complications occurred in 2 patients in the CB-1G group and 1 patient in the CB-2G group. CONCLUSIONS: The CB-2G significantly improved procedural efficacy compared to the CB-1G and provided reliable T(PVI) measurement. T(PVI) may be used to adjust application time and number individually in future studies. Final conclusions regarding the safety profile of the CB-2G requires additional research.

Energy titration strategies with the endoscopic ablation system: lessons from the high-dose vs. low-dose laser ablation study.

AIMS: To assess the effects of low-dose (LD) and high-dose (HD) ablation on acute and chronic success in patients with atrial fibrillation (AF). While the concept of visually guided pulmonary vein isolation (PVI) has been established little is known on energy titration using laser ablation. METHODS AND RESULTS: In 60 patients with AF, PVI using the endoscopic ablation system (EAS) was performed in two groups. Visually guided ablation was carried out after obtaining optimal tissue contact with 5.5-8.5 W in the LD group and with >8.5 W in the HD group. Acute PVI after a single visually guided circular lesion set was achieved in 89% (HD) and 69% (LD), respectively, (P = 0.0004). In 70 and 39% of patients all PVs were isolated after a single ablation circle in the HD and LD group, respectively, (P = 0.009). After gap ablation all PVs were isolated with the EAS. More energy was deployed (6483 ± 1834 vs. 5306 ± 2258 Ws; P ≤ 0.0001) with less applications (31.6 ± 8 vs. 35.2 ± 15 applications per PV; P = 0.03) leading to shorter procedure times (128 ± 17 vs. 154 ± 38 min; P = 0.001). During median follow-up of 311 days (261-346) recurrence rate was 17 and 40% in the HD and LD group, respectively. In both groups one phrenic nerve palsy was observed. CONCLUSION: For the first time, it was demonstrated that high ablation power affects acute and chronic outcomes. High-dose laser balloon ablation allows for an acute PVI rate of 89% solely by visually guided circular ablation and is associated with a chronic success rate of 83% after a single procedure.

Single transseptal big Cryoballoon pulmonary vein isolation using an inner lumen mapping catheter.

BACKGROUND: The single big cryoballon technique for pulmonary vein isolation (PVI) has been limited by the need for two transseptal punctures (TP). We therefore investigated feasibility and safety of a simplified approach using a single TP and a novel circumferential mapping catheter (CMC). METHODS: Patients underwent 28-mm cryoballoon PVI using a single TP. The CMC (Achieve(©) Medtronic Inc., Minneapolis, MN, USA) served as (1) guidewire and (2) as a PV mapping tool. Primary endpoint was PVI without switching to a regular guidewire. Secondary endpoints included: (1) PV signal quality during freezing, (2) time to PVI, (3) classification of successful ablation technique, (4) complications, and (5) procedural data. RESULTS: A total of 32 patients (126 PVs) were studied (mean age: 62 ± 11 years, 24 males, left atrium: 40 ± 4 mm). The primary endpoint was achieved in 29/32 patients (91%) and 123/126 PVs (98%) with a procedure and fluoroscopy time of 126 ± 26 minutes and 18.9 ± 7.5 minutes, respectively. Real-time visualization of PVI could be observed in 61/126 (48%) PVs. Time to sustained PVI versus nonsustained PVI was 66 ± 56 seconds versus 129 ± 76 seconds (P < 0.001). One phrenic nerve palsy was observed. After a follow-up of 250 ± 84 days 23/32 patients (72%) remained in sinus rhythm. CONCLUSION: The "simplified single big cryoballoon" PVI strategy appears to be safe and feasible. However, real-time PV recording was achieved in <50% of PVs. Therefore, further catheter refinements are warranted. (PACE 2012; 35:1304-1311).