Minimising radiation exposure in catheter ablation of ventricular arrhythmias

Abstract

Background: Conventional fluoroscopy guided catheter ablation (CA) is an established treatment option for ventricular arrhythmias (VAs). However, with the complex nature of most procedures, patients and staff bare an increased radiation exposure. Near-zero or zero-fluoroscopy CA is an alternative method which could substantially reduce or even eliminate the radiation dose. Our aim was to analyse procedural outcomes with fluoroscopy minimising approach for treatment of VAs in patients with structurally normal hearts (SNH) and structural heart disease (SHD).

Methods: Fifty-two (age 53.4 ± 17.8 years, 38 male, 14 female) consecutive patients who underwent CA of VAs in our institution between May 2018 and December 2019 were included. Procedures were performed primarily with the aid of the three-dimensional electro-anatomical mapping system and intra-cardiac echocardiography. Fluoroscopy was considered only in left ventricular (LV) summit mapping for coronary angiography and when epicardial approach was planned. Acute and long-term procedural outcomes were analysed.

Results: Sixty CA procedures were performed. Twenty-five patients had SHD-related VAs (Group 1) and 27 patients had SNH (Group 2). While Group 1 had significantly higher total procedural time (256.9 ± 71.7 vs 123.6 ± 42.2 min; p < 0.001) compared to Group 2, overall procedural success rate [77.4% (24/31) vs 89.7% (26/29); p = 0.20)] and recurrence rate after the first procedure [8/25, (32%) vs 8/27, (29.6%); p = 0.85] were similar in both groups. Fluoroscopy was used in 3 procedures in Group 1 where epicardial approach was needed and in 4 procedures in Group 2 where LV summit VAs were ablated. Overall procedure-related major complication rate was 5%.

Conclusions: Fluoroscopy minimising approach for CA of VAs is feasible and safe in patients with SHD and SNH. Fluoroscopy could not be completely abolished in VAs with epicardial and LV summit substrate location.

Keywords: Catheter ablation; Radiation exposure; Ventricular arrhythmia; Zero-fluoroscopy.

Fig. 1

Epicardial ablation. (A, B) Both present a modified left lateral view of a partial three-dimensional (3D) electro-anatomical mapping (EAM) voltage map of the epicardial part of the left ventricle (LV) with purple dots representing local abnormal ventricular activity (LAVA) sites inside and on the border of the low voltage area and red dots representing eventual ablation lesions. The white arrows mark the approximate location of the recorded LAVA as shown on intra-cardiac electrogram recordings made with multipolar mapping catheter presented on (C) (Pentaray 1–20) and with ablation catheter presented on (D) (ABLD and ABLP). The white asterisks mark the recorded isolated diastolic potentials at one of the eventual ablation sites near the course of the left circumflex artery (LCX) at the base of the epicardial side of the left ventricle. Before ablation at that site, selective left coronary angiography in a modified right anterior oblique view was performed as shown on (E, F). Red arrow on (E) points at the tip of the ablation catheter touching the proximal part of the LCX in which case the catheter was slightly withdrawn to the site marked with the white arrow on (F) showing the tip at the safe distance from the LCX at the location of the eventual successful ablation. CSD-CSP intra-cardiac electrograms recorded with a 10-polar diagnostic catheter in the right ventricle; I, II, aVF and V1 surface electrograms

Fig. 2

Left ventricular summit area ablation. (A) A modified right anterior oblique (RAO) view of a partial three-dimensional (3D) electro-anatomical mapping (EAM) activation map of the right atrium (RA), the coronary sinus (CS) and its continuation into the great cardiac vein (GCV) where the earliest local ventricular activation during left ventricular (LV) summit ventricular ectopy was found and successfully ablated (red dot). (B) Surface (I, III and V6) and intra-cardiac electrograms (ABLd and ABLp) revealing the earliest local ventricular activation (− 30 ms) during LV summit ectopy as recorded in the GCV. Before actual ablation at the earliest activation site selective left coronary angiography in a modified RAO view was performed as shown on (C, D). Red arrow on (C) points at the tip of the ablation catheter touching the proximal part of the LCX in which case the catheter was slightly withdrawn to the site marked with the white arrow on (D) showing the tip at the safe distance from the LCX at the location of the eventual successful ablation. His marks the His bundle location; SVC superior vena cava; IVC inferior vena cava