Periprocedural acute haemodynamic decompensation during substrate-based ablation of scar-related ventricular tachycardia: a rare and unpredictable event.

AIMS: Patients with structural heart disease (SHD) undergoing catheter ablation (CA) for ventricular tachycardia (VT) are at considerable risk of periprocedural complications, including acute haemodynamic decompensation (AHD). The PAINESD score was proposed to predict the risk of AHD. The goal of this study was to validate the PAINESD score using the retrospective analysis of data from a large-volume heart centre. METHODS AND RESULTS: Patients who had their first radiofrequency CA for SHD-related VT between August 2006 and December 2020 were included in the study. Procedures were mainly performed under conscious sedation. Substrate mapping/ablation was performed primarily during spontaneous rhythm or right ventricular pacing. A purposely established institutional registry for complications of invasive procedures was used to collect all periprocedural complications that were subsequently adjudicated using the source medical records. Acute haemodynamic decompensation triggered by CA procedure was defined as intraprocedural or early post-procedural (<12 h) development of acute pulmonary oedema or refractory hypotension requiring urgent intervention. The study cohort consisted of 1124 patients (age, 63 ± 13 years; males, 87%; ischaemic cardiomyopathy, 67%; electrical storm, 25%; New York Heart Association Class, 2.0 ± 1.0; left ventricular ejection fraction, 34 ± 12%; diabetes mellitus, 31%; chronic obstructive pulmonary disease, 12%). Their PAINESD score was 11.4 ± 6.6 (median, 12; interquartile range, 6-17). Acute haemodynamic decompensation complicated the CA procedure in 13/1124 = 1.2% patients and was not predicted by PAINESD score with AHD rates of 0.3, 1.8, and 1.1% in subgroups by previously published PAINESD terciles (<9, 9-14, and >14). However, the PAINESD score strongly predicted mortality during the follow-up. CONCLUSION: Primarily substrate-based CA of SHD-related VT performed under conscious sedation is associated with a substantially lower rate of AHD than previously reported. The PAINESD score did not predict these events. The application of the PAINESD score to the selection of patients for pre-emptive mechanical circulatory support should be reconsidered.

Case Report: Pulsed field ablation for epicardial right-sided accessory pathway.

We present a case of a 32-year-old male with a history of palpitations and preexcitation on ECG who underwent altogether four failed catheter ablations using different approaches in the two other electrophysiology centers within two years. ECG showed overt preexcitation with a positive delta wave in lead I and negative in leads V1-V3, suggesting a right free wall accessory pathway. During the electrophysiological study, the accessory pathway was localized on the free lateral wall. However, the electrograms and mapping during atrial and ventricular pacing suggested the presence of true epicardial accessory pathway. Repeated radiofrequency energy delivery with the support of the steerable sheath and excellent contact (as assessed by intracardiac echocardiography) at the earliest ventricular activation was not successful. Therefore, the Farawave catheter (Boston Scientific, Inc) was used, and a flower configuration with the intention to cover the entire atrial attachment of the pathway during ventricular pacing was selected. Application of pulsed field resulted in interruption of accessory pathway conduction. An electrophysiological study one year later confirmed the persistent effect of ablation. This case illustrates the potential utility of pulsed field energy for the ablation of atrial insertion of the accessory pathway with an epicardial course. Such an approach can avoid epicardial mapping and access and may improve the safety of the procedure.

Impact of access route to the left ventricle on asymptomatic periprocedural brain injury: the results of a randomized trial in patients undergoing catheter ablation of ventricular tachycardia.

AIMS: Catheter ablation of ventricular tachycardia (VT) is an effective treatment in patients with structural heart disease (SHD) and recurrent arrhythmias. However, the procedure is associated with the risk of complications, including both manifest and asymptomatic cerebral thromboembolic events. We hypothesized that periprocedural asymptomatic brain injury (ABI) can be reduced by using transseptal instead of the retrograde access route to the left ventricle (LV). METHODS AND RESULTS: Consecutive patients undergoing VT ablation for SHD were randomized 1:1 to either retrograde or transseptal LV access. All patients underwent radiofrequency ablation in conscious sedation with the use of an irrigated tip catheter. The degree of brain damage was evaluated by serum level of biomarker S100B. Significant ABI was defined as a post-ablation relative increase of S100B level >30%. A total of 144 patients (66 ± 9 years; 14 females; 90% coronary artery disease; LV ejection fraction: 30 ± 8%) were enrolled and 72 were allocated to each study groups. Symptomatic neurological complication of the procedure was not observed in any subject. A significant ABI was detected in 19.4% of patients. It was more commonly observed in subjects randomized to retrograde vs. transseptal LV access (26.4% vs. 12.5%, P = 0.04). In a multivariate analysis, only retrograde LV access and advanced age were independent determinants of significant ABI. CONCLUSION: Significant ABI after ablation of VT in patients with SHD can be detected in one-fifth of subjects. Retrograde access to LV is associated with a two-fold higher probability of significant ABI.