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Electrical isolation of the pulmonary veins (PVs) is the established endpoint during ablation of atrial fibrillation (AF) as implemented in the latest European guidelines. 1 Limitations of point-by-point radiofrequency (RF) ablation commonly utilized in combination with a three-dimensional (3D) electroanatomical mapping system led to the development and evaluation of alternative ablation systems and energy sources. The second-generation cryoballoon (CB, Arctic Front Advance, Medtronic, Inc.) is currently the only available ‘single-shot’ ablation tool for pulmonary vein isolation (PVI). Its ‘over-the-wire’ system allows for easy and non-traumatic advancement into the target PV. A spiral mapping catheter (Achieve, Medtronic, Inc.) introduced through the central lumen of the balloon records PV signals and permits live verification of PVI. The cooling system of the first-generation CB consisted of four injection jets in a more proximal balloon position, providing a ring-like zone of maximal cooling along the balloon equator, sparing the distal tip. In clinical use, the first-generation CB demonstrated a high acute success rate combined with a short learning curve. 2 In the Sustained Treatment Of Paroxysmal Atrial Fibrillation (STOP-AF) trial, the acute isolation rate was 97–100% applying a 300 s freeze cycle. 2 The high acute success rate was accompanied by a reasonable safety profile demonstrating an incidence of phrenic nerve (PN) palsy of 6.4%, an incidence of thermal esophageal ulceration of up to 5.2%, and a rate of PV stenosis of 0.9%. 3 However, the long-term single procedure success rate was only 62% and increased to 77% following multiple procedures. 4,5 The addition of two bonus freeze cycles when compared with a single bonus freeze application after successful PVI failed to demonstrate a significant improvement in 1-year clinical outcome. 6 The second-generation CB was introduced to overcome the limitations seen with the first-generation system. Despite an identical outer shape, the balloon incorporates a modified refrigerant injection system with eight injection jets located in a more distal position, providing effective and homogeneous cooling of the complete northern balloon hemisphere including the distal balloon tip. The aforementioned modifications led to the recommended shorter freeze cycle duration of 240 s. Initial studies using the secondgeneration CB demonstrated a high acute success rate with a PVI rate of up to 89% on first attempt. 7 Furthermore, the rate of live verification of PVI increased from 49% using the first-generation CB to 76% using the second-generation system. 8 While the procedural efficacy has increased, Casado-Arroyoetal. 9 reported an unacceptably high rate of PN palsy of 19% using the second-generation CB in their initial series of patients. The concern over a higher rate of PN palsy was not supported by a study from our centre reporting an incidence of 3.5%, which is comparable with the first-generation CB. 10 However, the reported rate of esophageal thermal injury of 12–19% is higher than that for the first-generation CB. 7,11 The first

Background Pulmonary vein isolation (PVI) is an established treatment option for paroxysmal atrial fibrillation. Recently, a novel endoscopic ablation system (EAS) was introduced. The incidence and severity of ablation-induced esophageal thermal lesions (ETLs) are unknown. Objective The purpose of this study was to investigate the incidence and severity of ablation-induced ETLs. Methods This prospective analysis compared two groups: group A underwent EAS-based PVI, and group B received PVI using radio frequency current (RFC). If esophageal temperature measured via an endoluminal temperature probe exceeded 38.5°C, energy application was stopped immediately. Endoscopy was performed 2 days postablation. Results Forty patients (20 female, mean age 56 ± 10 years) were treated with the EAS system (group A). In 20 patients (seven female, mean age 63 ± 9 years) RFC-based PVI was performed (group B). Esophageal endoscopy was performed 2.1 ± 0.8 (group A) and 2.8 ± 1.2 days postablation (group B), respectively. In 7/40 patients (18%) in group A, thermal lesions (four thermal ulcerations, three minimal thermal lesions) were detected. In group B, 3/20 patients (15%) displayed thermal lesions (three minimal thermal lesions). All thermal lesions resolved upon repeat endoscopy performed 8 ± 6 (group A) and 5 ± 1 days (group B) after initial endoscopy. Conclusion In the EAS group, ETLs were found in 18% of patients, as compared with in 15% in the RFC group. In patients with ETLs, ulcerations were found in 57% in the EAS group, as compared with 0% in the RFC group. This may indicate that the quality of thermal lesions is more severe in the EAS group. Further investigation is required.

Background A persistent left superior vena cava (PLSVC) is an uncommon cardiac anomaly. Objective The purpose of this study was to assess the complication rate and procedural outcome in patients with PLSVC who were referred for catheter ablation of atrial fibrillation (AF). Methods Between September 2006 and February 2009, seven patients referred for circumferential pulmonary vein (PV) isolation (PVI) demonstrated a PLSVC. PVI was confirmed by spiral catheter recording within the respective PVs. Ablation within the PLSVC was performed using an irrigated-tip catheter (energy settings 20 W, 43°C, flow rate 17 mL/min) or, alternatively, a cryoballoon catheter (28 mm balloon, 300-second energy application). Patients were analyzed according to procedural outcome and rate of complications. Results Among seven patients (three female, mean age 57 ± 8 years, two paroxysmal, five persistent AF, structural/congenital heart disease present in three patients, mean left atrial size 43 ± 6 mm), 14 ablation procedures were performed. Two major complications (left phrenic nerve injury and cardiac tamponade) occurred in two of four patients undergoing PLSVC ablation. Of four of seven patients undergoing PLSVC ablation, two patients needed one and one patient needed two redo PLSVC ablation procedures. The first-time procedural success rate was 29%, while the overall success rate reached 86% after a median follow-up period of 621 (339–1,289) days. Conclusion In patients with ectopic activity from a PLSVC, the ablative strategy should include isolation of the PLSVC as a procedural endpoint, although multiple ablation procedures may be necessary to achieve stable sinus rhythm. Contrary to previous reports, complications are common if the PLSVC is targeted for ablation.

Esophageal Injury Following Robotic Navigation. Introduction: Robotic navigation (RN) is a novel technology for pulmonary vein isolation (PVI). We investigated the incidence of thermal esophageal injury using RN with commonly used power settings in comparison to manual PVI procedures. Methods: Thirty-nine patients underwent circumferential PVI using a 3.5-mm irrigated-tip-catheter. In the manual (n = 25) and the RN1 group (n = 4) power was limited to 30 W (17 mL/min flow, maximal temperature 43°C, max. 30 sec/spot) at the posterior left atrial (LA) wall. In RN-based procedures, ablation was performed with a contact force of 10–40 g. The operator was blinded to the esophageal temperature (Teso). In the RN2 group ablation power along the posterior LA wall was reduced to 20 W and ablation terminated at Teso of 41°C. Endoscopy was carried out 2 days postablation. Results: PVI was achieved in all patients. In the manual group no esophageal lesions, minimal lesions, or ulcerations were found in 15 of 25 (60%), 7 of 25 (28%), and 3 of 25 (12%) patients, respectively. All patients in the RN1 group had an ulceration and one developed esophageal perforation. A covered stent was placed 14 days post-PVI and removed at day 81. In the RN2 group, only a single minimal lesion was found. Conclusions: A high incidence of thermal esophageal injury including a perforation was noted following robotic PVI using 30 W along the posterior LA wall. During RN-based PVI procedures esophageal temperature monitoring is advocated. Reduction of ablation power to 20 W and termination of energy delivery at Teso of 41°C significantly reduced the risk of esophageal injury. (J Cardiovasc Electrophysiol, Vol. 21, pp. 853-858, August 2010)

The purpose of this study was to evaluate subclinical atherosclerosis in retired professional football players. Two hundred one healthy former professional football players (mean age 50.8 years; mean body mass index 31.5 kg/m2) were screened for the prevalence of cardiovascular risk factors, metabolic syndrome, and subclinical atherosclerosis by carotid artery ultrasound and compared with a cohort of men of similar body mass index referred for the assessment of subclinical atherosclerosis by carotid ultrasound. The prevalence of carotid artery plaque in the players was not significantly different from that of the body mass index–matched patients (33.3% vs 29.3%, p = 0.45). For the 2 groups, the prevalence of carotid artery plaque was >3 times higher than that reported in general population studies of patients with the same age range, gender, and exclusions. Metabolic syndrome prevalence was higher in linemen than in nonlinemen (45.8% vs 22.5%, p = 0.001), but there was no statistical difference in plaque presence between linemen and nonlinemen (27.1% vs 35.9%, p = 0.23). In conclusion, despite their elite athletic histories, former professional football players have a similar prevalence of advanced subclinical atherosclerosis as a clinically referred population of overweight and obese men.

Pulmonary Vein Conduction During Cryoballoon Ablation. Introduction: Cryoballoon (CB) ablation represents a novel technology for pulmonary vein isolation (PVI). We investigated feasibility and safety of CB-PVI, utilizing a novel spiral catheter (SC), thereby obtaining real-time PV potential registration. Methods: Following double transseptal puncture, a Lasso catheter (Biosense Webster, Diamond Bar, CA, USA) and the 28 mm CB were positioned within the left atrium. A novel SC (Promap, ProRhythm Inc., Ronkonkoma, NY, USA) was inserted through the lumen of the CB allowing PV signal registration during treatment. Time to PV conduction block was analyzed. If no stable balloon position was obtained, the SC was exchanged for a regular guide wire and PV conduction was assessed after treatment by Lasso catheter. Results: In 18 patients, 39 of 72 PVs (54%) were successfully isolated using the SC. The remaining 33 PVs were isolated switching to the regular guide wire. Time to PV conduction block was significantly shorter in PVs in which sustained PVI was achieved as compared to PVs in which PV conduction recovered within 30 minutes (33 +/- 21 seconds vs 99 +/- 65 seconds). In 40 PVs, time to PV conduction block was not obtained because of: (1) PVI not being achieved during initial treatment; (2) a distal position of the SC; or (3) isolation with regular guide wire. No procedural complications occurred. Conclusion: Visualization of real-time PV conduction during CB PVI is safe, feasible, and allows accurate timing of PVI onset in a subset of PVs. Time to PV conduction block predicts sustained PVI. However, mechanical properties of the SC need to be improved to further simplify CB PVI. (J Cardiovasc Electrophysiol, Vol. pp. 1-8). ispartof: Journal of Cardiovascular Electrophysiology vol:20 issue:11 pages:1203-1210 ispartof: location:United States status: published

Transient cardiac apical ballooning syndrome (TCABS) is diagnosed by transthoracic echocardiography demonstrating apical akinesis with left ventricular (LV) apical ballooning and preserved mid-to-basal LV systolic function, and left heart catheterization showing the absence of significant obstructive epicardial coronary artery disease. Presenting symptoms are suggestive of an acute coronary syndrome and electrocardiogram findings mimic acute myocardial injury. Right ventricular involvement has been reported. We describe a case of acute pacemaker dysfunction caused by the TCABS, which responded to conservative therapy.

Objective: In patients referred for catheter ablation for the treatment of atrial fibrillation, multislice computed tomography angiography of the thorax is routinely performed to assess pulmonary vein anatomy. We sought to investigate the incidence of unexpected cardiac and extracardiac findings in this select patient population and to establish how these findings influence subsequent patient care. Methods: Ninety-five patients (mean age 62 ± 10 years, 35% female) referred to our institution for ablation therapy for atrial fibrillation between July 2003 and October 2007 underwent multislice computed tomography angiography of the thorax. Radiologists interpreted all images. Need for additional testing, consultation and eventual diagnosis were assessed by electronic record review. Results: A total of 83 (5 cardiac, 78 extracardiac) unexpected findings were observed in 50/95 (53%) of patients. The findings prompted 23 additional tests (5 cardiac, 18 noncardiac) in 15/95 (16%) of patients and 8 subsequent referrals in 7/95 (7%) patients. In 6 patients the findings significantly altered future patient care and resulted in postponement of ablation therapy in 4 patients. In 2 patients, extracardiac findings (pulmonary emboli and adenocarcinoma of the lung) were of potentially life-saving consequence. Conclusions: In patients undergoing multislice computed tomography angiography of the thorax in anticipation of planned catheter ablation therapy for the treatment of atrial fibrillation, unexpected findings are common and of potentially significant value. In comparison, there is a higher prevalence of unexpected extracardiac, rather than cardiac findings. Further investigation of these findings may lead to postponement of ablation therapy, but may also be of potentially lifesaving consequence.

Ablation of atrial fibrillation (AF) is an established treatment option for symptomatic patients refractory to antiarrhythmic medication. In patients with paroxysmal AF, ablation can be offered as first-line therapy when performed in an experienced centre. The accepted cornerstone for all ablation strategies is isolation of the pulmonary veins. However, it is still challenging to achieve contiguous, transmural, permanent lesions using radio-frequency current (RFC) based catheters in conjunction with a three-dimensional mapping system and the learning curve remains long. These limitations have kindled interest in developing and evaluating novel catheter designs that incorporate alternative energy sources. Novel catheters include balloon-based ablation systems, incorporating different energy modalities such as laser (HeartlightTM, CardioFocus, Marlborough, MA, US), RFC (Hot Balloon Catheter, Hayama Arrhythmia Institute, Kanagawa, Japan) and cryo-energy (ArcticFront, Medtronic, Inc., Minneapolis, MN, US). While the cryoballoon (CB) and the radiofrequency hot balloon (RHB) are single-shot devices, the endoscopic ablation system (EAS) allows for point-by-point ablation. The CB and EAS are well established as safe, time-efficient and effective ablation tools. Initial studies using the RHB could also demonstrate promising results. However, more data are required.

Accessory pathways are rarely seen at the aortic-mitral continuity. A 27-year-old male presented with wide-complex tachycardia. Sinus rhythm electrocardiogram demonstrated pre-excitation, positive in V1-6, I-III, aVF, negative in aVL and aVR. Programmed stimulation showed non-decremental conduction. Morphology of pre-excited beats was similar to ventricular arrhythmias from the left coronary cusp (LCC). Earliest ventricular activation was …

We thank Drs Yamada and Kay for their comments regarding our article “Ventricular arrhythmias arising from the left ventricular outflow tract below the aortic sinus cusps: mapping and catheter ablation via transseptal approach and electrocardiographic characteristics.”1 The main issues raised by Drs Yamada and Kay focused around the transseptal approach used in our study to obtain better access to the area termed the LV summit. We agree with the authors that using the retrograde aortic approach and with the catheter inversion technique, some of the regions beneath the aortic sinus cusps (ASC) can be reached. However, when this is performed with the 3D mapping system, one can see that in the majority of the time, there is a distance between …

Since the seminal paper by Haissaguerre et al. ([1][1]) describing the importance of pulmonary vein (PV) triggers in the initiation of paroxysmal atrial fibrillation (AF), PV isolation has become the cornerstone of catheter ablation for AF, demonstrating acceptable results ([2,3][2]). By contrast

Since the initial description of the pivotal role of the pulmonary veins (PVs) in the initiation of atrial fibrillation (AF), significant strides have been made in the ablative treatment of AF.1 Recently, 5-year follow-up data on the outcome following PV isolation for the treatment of AF were reported.2 3 In patients with paroxysmal AF, arrhythmia recurrence was common following initial PV isolation but decreased to about 20% after a median of one (one to three) procedure.2 In a second study, success rate was lower in patients with long-standing persistent AF.3 In a systematic review, non-paroxysmal AF was an independent risk predictor for arrhythmia recurrence following first-time PV isolation.4 Several other factors have demonstrated predictive value in patients undergoing AF ablation. Left atrial (LA) size commonly serves as a surrogate marker for atrial remodelling and is easily and reproducibly measured using preprocedural echocardiography. LA diameter predicts first-time occurrence of AF as well …

the His-bundle at a midseptal or anteroseptal location, increasing the risk of inadvertent complete atrioventricular block. The use of a long sheath may facilitate catheter stability if the accessory pathway is located along the right midseptal or anteroseptal region. In these cases, we favour advancement of the ablation catheter from the right jugular vein, since this site of access is in direct alignment with the location of the accessory pathway. Stable wall contact is accomplished by counterclockwise torque of the catheter. In addition, we found that an anteroseptal pathway may be successfully ablated from the non-coronary cusp. 7 Some operators prefer to use cryothermia. Our laboratory routinely uses RF current when ablating para-Hisian pathways. A His potential is practically always recorded at the earliest site of accessory pathway activation. However, the His bundle is protected by fibrous tissue, whereas the accessory pathway is superficially located, making damage to the His bundle very unlikely with the judicious use of RF energy. An epicardial accessory pathway location may not be amenable to a routine endocardial approach. If a posteroseptal accessory pathway is suspected, coronary sinus angiography will facilitate proper anatomic delineation and catheter ablation. In 21% of patients with a suspected posteroseptal or left posterior accessory pathway, coronary sinus angiography demonstrated a diverticulum originating from the middle cardiac vein, coronary sinus, or both. 8 Ablation is performed by advancing the ablation catheter into the coronary sinus, targeting the neck of the diverticulum. In rare cases, an epicardial accessory pathway may mimic electrocardiographic criteria of a manifest right anteroseptal accessory pathway. Clues to the correct diagnosis during endocardial

An 18-year-old male athlete sustained exertional sudden cardiac death. Evaluation and intervention revealed the finding of an anomalous origin of the left coronary artery circulation from the opposite coronary sinus.

Purpose: The aim of this study was to evaluate the location and the ratio of high/low contact force (CF) during left atrial (LA) mapping. Methods: CF during point-by-point LA mapping were assessed in 50 patients. In 30 patients, the operators were blinded to the CF during the procedure (Group A). In 20 patients, the CF was displayed to the operators (Group B). As a parameter of the catheter stability, relative standard deviation (RSD=standard deviation of CF*100 /mean CF) was calculated at each mapping point. Data were analyzed according to 11 predefined areas (Figure). In Group B, the optimal CF was defined to be 10-40g and the operators attempted to acquire points (pts) in this optimal range. We compared the CF and the catheter stability between 2 groups. Results: A total of 5866 mapping pts were analyzed (3467 pts in Group A and 2399 pts in Group B). Mean CF was 20±19g in Group A and 19±11g in Group B. Low CF 40g was noted at 414 pts (12%) in Group A and 67 pts (3%) in Group B (P 100g was noted at 22 pts (0.6%) in Group A, no CF>100g point was noted in Group B (P

Background: Ventricular tachycardia (VT) may occur after anterior wall myocardial infarction. The best ablation strategy is unclear. We report about three patients in whom isolation oft the entire substrate was performed. Methods: Three patients (66±5 years, LVEF 29±14%) underwent catheter ablation for sustained VT after anterior wall myocardial infarction. All patients had recurrent ICD shocks (VT storm in two) despite amiodarone therapy. During electrophysiological-study, 4±2 VTs were induced including the clinical VT. 3D-mapping of the left ventricle (LV) was performed in SR (n=2) or during RV pacing (n=1) and revealed a low-voltage (

Objectives: This study investigated the correlation between endocardial substrate and requirement for epicardial radiofrequency ablation (RFA) of ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods: 25 patients (18 male; aged 43±17; range 15 to 78 years) with ARVC undergoing RFA were included. Arrhythmogenic substrate was defined as an area with an amplitude

Objectives: The purpose of this study was to assess the need of epicardial ablation for ventricular tachycardia (VT) late after myocardial infarction (MI). Methods: Substrate endocardial electroanatomic mapping was performed for VT late after MI. Arrhythmogenic substrate was defined as a low voltage are (

A 46-year-old female was referred for catheter ablation of symptomatic, drug-refractory atrial fibrillation (AF). Left atrial diameter was 52 mm. Chest radiography demonstrated the right-sided heart ( Panel A ). Cardiac magnetic resonance imaging classified this as dextrocardia (base to apex pointing to the right) with situs solitus (normal visceral situs with concordant atrial situs, Panel B ). The morphological right ventricle, identified by the presence of the moderator band, coarse apical trabeculations, and infundibulum, was connected to the right atrium (concordant atrioventricular connections) confirming normal so-called D-loop ventricular development and orientation ( Panel C ). Ventriculo-arterial connections were also concordant (aorta located left and posterior to pulmonary artery). Circumferential pulmonary vein (PV) isolation was performed for the treatment of AF. Double …

Background Second-generation cryoballoon based pulmonary vein isolation has demonstrated encouraging acute and mid-term clinical outcome. Customarily, a bonus-freeze is applied after successful pulmonary vein isolation. Objective To compare the long-term clinical outcome and safety profile of a bonus-freeze and a no bonus-freeze protocol. Methods A total of 120 consecutive patients with paroxysmal [95/120 (79 %)] or persistent atrial fibrillation [25/120 (21 %)] underwent CB2-based PVI. Freeze-cycle duration was 240 s. In the first 60 patients a bonus-freeze was applied after successful PVI (group 1), while in the following 60 patients the bonus-freeze was omitted (group 2). Results Procedure and fluoroscopy times were significantly shorter in group 2 [113.8 ± 32 vs 138.2 ± 29 min (p = 0.03) and 19.2 ± 6 vs 24.3 ± 8 min (p = 0.02)]. No differences in procedural complications were found. During a mean follow-up of 849 ± 74 (group 1) and 848 ± 101 days (group 2, p = 0.13) 69 % of patients (group 1) and 67 % of patients (group 2) remained in stable sinus rhythm without any differences between the groups (p = 0.69). Conclusions Freedom from atrial fibrillation after second-generation cryoballoon based pulmonary vein isolation and a follow-up of >2 years is comparable when applying a bonus- and a no bonus-freeze protocol, while procedure and fluoroscopy times are significantly shorter when omitting the bonus-freeze. No differences in periprocedural complications were identified.