Transseptal puncture for atrial fibrillation ablation is a safe and common procedure, however, complications, such as cardiac tamponade, are possibly fatal if not recognized and treated. Our goal is to report a case in which management of an inadvertent puncture of the posterior wall of the left atrium was accomplished using an unusual technique, followed by successful pulmonary vein isolation, and without the need of subsequent subxiphoid puncture.

Introduction: The autonomous system plays an important role as a trigger of cardiac arrhythmias. Cardiac sympathetic denervation (CSD) achieved by stellate and proximal thoracic ganglia resection has been reported as an alternative approach for the management of ventricular arrhythmias (VA) in structural heart disease (SHD) patients. Insufficient data regarding Chagas Disease (ChD) is available. Methods: Patients who underwent CSD for better management of ventricular arrhythmias (VA) in SHD, mainly ChD, in a single tertiary center in Brazil were evaluated for safety and efficacy outcomes. Results: Between June 2014 and March 2020, fourteen patients (age 59±7.5, 85% male, mean ejection fraction 30.5±7.9%) were submitted to left or bilateral CSD. In a median follow-up time of 143 (Q1: 30; Q3: 374) days, eight patients (57,2%) presented VT recurrence. A significant reduction in the median burden of ventricular arrhythmias comparing six months before and after procedure (10 to 0; p=0.004). For the nine ChD patients, the median burden of appropriate therapies was also reduced (11 to 0; p=0.008). There were two cases of clinically relevant pneumothorax and three cases of transient hemodynamic instability, but no direct procedure-related deaths occurred. Additionally, there was no long-term adverse events, Conclusion: CSD is safe and seems to be effective in reducing the burden of VT/VT storm in SHD patients, including ChD patients. Randomized trials are needed to clarify its role in the management of these patients.

BACKGROUND Direct comparisons of combined (C-ABL) and non-combined (NC-ABL) endo-epicardial ventricular tachycardia (VT) ablation outcomes are scarce. We aimed to investigate the long-term clinical efficacy and safety of these 2 strategies in ischemic heart disease (IHD) and nonischemic cardiomyopathy (NICM) patients. METHODS Multicentric observational registry including 316 consecutive patients who underwent catheter ablation for drug-resistant VT between January 2008 and July 2019. Primary and secondary efficacy endpoints were defined as VT-free survival and all-cause death after ablation. Safety outcomes were defined by 30-days mortality and procedure-related complications. RESULTS Most of the patients were male (85%), with IHD (67%) and mean age of 63±13 years. During a mean follow-up of 3±2 years, 117 (37%) patients had VT recurrence and 73 (23%) died. Multivariate survival analysis identified electrical storm (ES) at presentation, IHD, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class III/IV, and C-ABL as independent predictors of VT recurrence. In 135 patients undergoing repeated procedures, only C-ABL and ES were independent predictors of relapse. The independent predictors of mortality were C-ABL, ES, LVEF, age and NYHA class III/IV. C-ABL survival benefit was only seen in patients with a previous ablation (P for interaction=0.04). Mortality at 30-days was similar between NC-ABL and C-ABL (4% vs. 2%, respectively, P=0.777), as was complication rate (10.3% vs. 15.1% respectively, P=0.336). CONCLUSION A combined endo-epicardial approach was associated with greater VT-free survival and lower all-cause death in IHD and NICM patients undergoing repeated VT catheter ablations. Both strategies seem equally safe.

Introduction: Cardiac autonomic system modulation by endocardial ablation targeting atrial ganglionated plexi (GP) is an alternative strategy in selected patients with severe functional bradyarrhythmias, although no consensus exists on the best ablation strategy. The aim of this study was to evaluate if a simplified approach by a purely anatomical guided ablation of just the atrial right GP is enough for the treatment of these patients. Methods: We prospectively enrolled patients with significant functional bradyarrhythmias and performed endocardial ablation purely guided by 3D electroanatomic mapping directed at the atrial right GP and accessed parameters of parasympathetic modulation and recurrence of bradyarrhythmias. Results: Thirteen patients enrolled (76.9% male, median age 51, 42-63 years). After ablation, a median RR interval shortening of 28.3 (25.6–40.3)% occurred (111, 937.5-1395.4ms to 722.9, 652.2-882.4ms, p=0.0015). The AH interval also shortened (19, 10.5–35.7%) significantly after the procedure (115, 105-122ms to 85, 71-105ms, p=0.002) as well as Wenckebach cycle length (11.1, 5.9–17.8% shortening) from 450, 440-510ms to 430, 400-460ms, p=0.0014. On 24-hour Holter monitoring there was significant increase in heart rates (HR) of patients after ablation (minimal HR increased from 34 (26-43)bpm to 49 (43–56)bpm, p=0,0063 and mean HR from 65 (47-72)bpm to 78 (67-87)bpm, p=0.0015). No patients had recurrence of symptoms or significant bradyarrhythmias during a median follow-up of 8.4 months. Conclusions: A purely anatomic guided procedure directed only at the atrial right ganglionated plexi seems to be enough as a therapeutic approach for cardiac parasympathetic modulation in selected patients with significant functional bradyarrhythmias.

We thank Dr Shah and colleagues for their interest, analysis of the presented data and comments related to our paper1. Circumferential PV isolation using 8mm tip catheter is still currently used in our institution for some patients due to economic reasons, so we can provide AF ablation for a portion of the population for whom there is no private insurance available, with adequate safety and results (recurrence rate in this series was 15.6% in a follow-up of 11±5 months)2. Those catheters have two temperature sensors, thus reducing the risk of clot formation on the tip of the catheter. For the same reason, our institutional standard when using such catheters is to deliver RF applications in temperature-controlled mode with maximum temperature of 55ºC. This mode of RF application is different compared to irrigated tip catheters and the mode of application used in the cited experimental study mentioned by the authors, in which it was used power-controlled RF applications.3 Due to the temperature-controlled mode of RF application, the cooling of esophagus generates a convective cooling of the atrial wall close to the esophagus and the catheter interface, leading to the higher power RF application that was observed in Group III.2 Probably due to this higher power of application, there was a higher rate of esophageal and periesophageal lesions injuries in the esophageal cooling group. This rate was however acceptable, since we used esophagogastroduodenoscopies (EGD) combined with radial endosonographies (EUS), that is a high sensitivity method of screening for esophageal lesion. Additionally, there were no severe or clinically significant lesions in any of the patients. A prior experimental model we performed some years ago also suggests this hypothesis.4 This model was similar to the one used by Montoya and cols3 and we could find deeper lesions with esophageal cooling and temperature-controlled applications, but similar depth, when power-controlled applications were performed.4 In silico models could also be used to evaluate the different effects of esophageal cooling using temperature or power-controlled RF applications. So, we think that the flow used in our studied balloon was not the reason for the findings, but the mode of application, although even in the esophageal cooling group the incidence of lesions was low.    This was a prototype balloon used for the first time in clinical studies, and it was not possible to measure inflow and outflow temperature, being not possible to define heat transfer capacity. However, as presented before, as there was a higher RF power in group III we can infer that we achieved some cooling on the esophagus-atrium interface. Tsuchiya and cols showed a reduction in luminal esophageal temperature using an esophageal balloon with irrigation flow similar to our study.5We strongly agree with the authors that a higher flow of irrigation and consequential higher temperature reduction could be more protective, especially using power-controlled RF applications. Additionally, we think that esophageal cooling strategies are a promising strategy to avoid severe esophageal lesions, especially with contact sensor, power-controlled RF applications, allowing more effective atrial lesions close to the esophagus, thus improving AF ablation results.   References 1.         Shah S, Mercado Montoya M, Zagrodzky J, Kulstad E. Letter to the Editor regarding the paper "Comparative study of strategies to prevent esophageal and periesophageal injury during atrial fibrillation ablation". Journal of Cardiovascular Electrophysiology. 2020.2.         de Oliveira BD, Oyama H, Hardy CA, et al. Comparative study of strategies to prevent esophageal and periesophageal injury during atrial fibrillation ablation. J Cardiovasc Electrophysiol. 2020;31(4):924-933.3.         Montoya MM, Mickelsen S, Clark B, et al. Protecting the esophagus from thermal injury during radiofrequency ablation with an esophageal cooling device. J Atr Fibrillation. 2019;11(5):2110.4.         Scanavacca MI, Neto S, Pisani CF, et al. Cooled intra-esophageal balloon to prevent thermal injury of esophageal wall during radiofrequency ablation. Heart rhythm. 2007;4(5):S117.5.         Tsuchiya T, Ashikaga K, Nakagawa S, Hayashida K, Kugimiya H. Atrial fibrillation ablation with esophageal cooling with a cooled water-irrigated intraesophageal balloon: a pilot study. J Cardiovasc Electrophysiol. 2007;18(2):145-150.