Non-fluoroscopic navigation systems for radiofrequency catheter ablation for supraventricular tachycardia reduce ionising radiation exposure

Longitudinal reduction in fluoroscopy with continued use of 3-dimensional electroanatomic mapping systems in catheter ablation of supraventricular tachycardia - then and now

BACKGROUND

Catheter ablation is a first-line treatment for symptomatic, recurrent supraventricular tachycardia (SVT). This study aims to demonstrate if 3D-electroanatomic mapping (EAM) during SVT ablation reduces fluoroscopy time (FT) and determine if further reductions in FT are observed longitudinally.

METHODS

All cases of SVT ablation between May 2011-May 2022 at a single tertiary centre were prospectively recruited. FT between the cohorts with and without EAM were compared. Within the EAM subset, the trend of FT across the years was analysed.

RESULTS

There were 1758 cases included, 563 without EAM, 1195 with EAM. EAM was associated with a longer procedure time (mean + 8.8 min, p = 0.001), but with mean reductions in FT and dose area product (DAP) by 19.6 min and 18 621 mGy*cm2 respectively (p < 0.001). There was comparable efficacy without any increase in complication rates. Over time (2011-2022), further reduction in FT of 0.9 min year on year was observed (p = 0.001). Between 2011 and 2017, there was a significant reduction in FT of 1.1 min year on year (p = 0.019), which was not observed from 2017 onwards (p = 0.061). The greatest reduction in FT was after the first year of adoption.

CONCLUSION

EAM in SVT ablation reduces fluoroscopy use. FT was initially observed to reduce further over time before plateauing, likely due to increased operator experience. While there is increased interest in zero fluoroscopy SVT ablation, complementary use of fluoroscopy may still be necessary in complex cases.

Zero and Minimal Fluoroscopic Approaches During Ablation of Supraventricular Tachycardias: A Systematic Review and Meta-Analysis

Introduction

Catheter ablations for cardiac arrhythmias are conventionally performed under fluoroscopic guidance. To guide these procedures, zero/minimal fluoroscopy (Z/MF) approaches have become available, using three-dimensional electroanatomical mapping systems. Our aim was to conduct a meta-analysis comparing these two different methods for the treatment of paroxysmal supraventricular tachycardia (SVT).

Methods

Electronic databases were searched and systematically reviewed for studies comparing procedural parameters and outcomes of conventional, fluoroscopy-guided vs. Z/MF approaches in patients undergoing electrophysiology (EP) procedures for SVTs. The random-effects model was used to derive mean difference (MD) and risk ratios (RRs) with 95% confidence interval (CI).

Results

Twenty-four studies involving 9,074 patients met our inclusion criteria. There was no difference between the groups in terms of acute success rate (RR = 1.00, 95% CI, 0.99–1.01; p = 0.97) and long-term success rate (RR: 1.01, 95% CI, 1.00–1.03; p = 0.13). Compared to the conventional method, zero-and-minimal fluoroscopy (Z/MF) ablation significantly reduced fluoroscopic time [MD: −1.58 min (95% CI, −2.21 to −0.96 min; p < 0.01)] and ablation time [MD: −25.23 s (95% CI: −42.04 to −8.43 s; p < 0.01)]. No difference could be detected between the two groups in terms of the procedure time [MD: 3.06 min (95% CI: −0.97 to 7.08; p = 0.14)] and the number of ablation applications [MD: 0.13 (95% CI: −0.86 to 1.11; p = 0.80)]. The complication rate was 1.59% in the entire study population and did not differ among the groups (RR: 0.68, 95% CI: 0.45–1.05; p = 0.08).

Conclusions

The Z/MF approach for the catheter ablation of SVTs is a feasible method that reduces radiation exposure and ablation time without compromising the acute and long-term success or complication rates.

Current status of pediatric electrophysiology in Latin America: a LAHRS survey

PURPOSE

Over the last years, pediatric electrophysiology (EP) has evolved as a consolidated subspecialty of pediatric cardiology. In the USA, Canada, and Europe, there is a clear picture of the status of pediatric EP, but the situation in Latin America is largely unknown.

METHODS

A descriptive cross-sectional observational study was performed. A survey was conducted by the Latin American Heart Rhythm Society in Spanish and Portuguese to assess the status of development of pediatric EP across Latin American countries.

RESULTS

There are physicians practicing pediatric EP in 11 Latin American countries. The scope of the practices includes clinical and non-invasive EP as well as performing invasive EP procedures. All the current pediatric EP interventions are performed in most of Latin American countries.

CONCLUSIONS

Pediatric electrophysiology is present as a subspecialty in half of the countries in Latin America, and all the current electrophysiology procedures and therapeutic technologies are available in most Latin American countries.

Zero-fluoroscopy approach for ablation of supraventricular tachycardia using the Ensite NavX system: a multicenter experience

BACKGROUND

Three-dimensional electroanatomic mapping systems have demonstrated a significant reduction in radiation exposure during radiofrequency catheter ablation procedures. We aimed to investigate the safety, feasibility and efficacy of a completely zero-fluoroscopy approach for catheter ablation of supraventricular tachycardia using the Ensite NavX navigation system compared with a conventional fluoroscopy approach.

METHODS

A multicenter prospective non-randomized registry study was performed in seven centers from January 2013 to February 2018. Consecutive patients referred for catheter ablation of supraventricular tachycardia were assigned either to a completely zero-fluoroscopic approach (ZF) or conventional fluoroscopy approach (CF) according to the operator's preference. Patients with atrial tachycardia were excluded.

RESULTS

Totally, 1020 patients were enrolled in ZF group; 2040 patients ablated by CF approach were selected for controls. There was no significant difference between the zero-fluoroscopy group and conventional fluoroscopy group as to procedure time (60.3 ± 20.3 vs. 59.7 ± 22.6 min, P = 0.90), immediate success rate of procedure (98.8% vs. 99.2%, P = 0.22), arrhythmia recurrence (0.4% vs. 0.5%, P = 0.85), total success rate of procedure (98.4% vs. 98.8%, P = 0.39) or complications (1.1% vs. 1.5%, P = 0.41). Compared with the conventional fluoroscopy approach, the zero-fluoroscopy approach provided similar outcomes without compromising the safety or efficacy of the procedure.

CONCLUSION

The completely zero-fluoroscopy approach demonstrated safety and efficacy comparable to a conventional fluoroscopy approach for catheter ablation of supraventricular tachycardia, and mitigated radiation exposure to both patients and operators.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT03042078; first registered February 3, 2017; retrospectively registered.

Clinical approach to the knotting diagnostic quadripolar catheter during zero-fluoro electrophysiological study

We report a case of electrophysiology catheter knotting when inserted without fluoroscopic guidance followed by technique to unravel the knot via ipsilateral femoral vein. We advocate caution when manipulating catheters using minimal/zero fluoroscopic technique and having a low threshold to screen under fluoroscopy when encountering difficulties during catheter insertion.

Catheter ablation for supraventricular tachycardia in children ≤ 20 kg using an electroanatomical system

PURPOSE

Catheter ablation is the only choice of treatment in some small children with medically refractory supraventricular tachycardia (SVT). Electroanatomical mapping systems (EMS) are more commonly utilized in electrophysiological procedures in recent years, which resulted in a significant decrease in fluoroscopy exposure. The potential benefit of EMS in small children has not been studied. Therefore, we investigated the outcomes of children undergoing catheter ablation weighing ≤ 20 kg using an electroanatomical mapping system.

METHODS

This study evaluated the outcomes, characteristics, and follow-ups of children ≤ 20 kg who underwent SVT ablations between April 2012 and April 2018 in a pediatric electrophysiology center where EMS were routinely used.

RESULTS

In a 6-year period, 1129 children underwent SVT catheter ablation under EMS guidance at our institution. A total of 84 of them were weighing ≤ 20 kg. The acute success rate was 97.6% in 85 tachycardia substrates. No fluoroscopy was used in 58 of the patients, while a median of 5 (4-14) min of fluoroscopy was used in the remaining 26 patients. Recurrences were seen in 4 patients (4.8%) at a mean follow-up of 3.89 ± 2.08 years. Five patients developed non-vital complications (2 right bundle block and 3 temporary complete block that spontaneously resolved during the procedure).

CONCLUSIONS

The outcome of catheter ablation with the guidance of EMS for the treatment of SVT in small children is favorable. Fluoroscopy exposure can be decreased and even eliminated in most patients.

Treatment of left accessory cardiac pathway conduction disorders using radiofrequency catheter ablation under the guidance of the Ensite NavX 3D mapping system: a retrospective study

To investigate the effectiveness and safety of using the Ensite NavX three-dimensional (3D) mapping system during Radiofrequency catheter ablation (RFCA) of left accessory pathway (AP) disorders. A total of 227 patients having their left AP treated by RFCA, were classified into study group (n = 112) and the control group (n = 115). X-ray irradiation time and exposure doses during the course of the operations were recorded. Time taken to place the mapping catheter along with total duration of operations and procedural complications were compared. The X-ray irradiation time and exposure doses in the course of manipulating the ablation catheters were significantly lower in the study group compared to control (5.1 ± 2.3 min vs. 13.1 ± 3.1 min; P < 0.05 and 5.7 ± 2.6 mGy vs. 17.8 ± 4.3 mGy; P < 0.05, respectively). The total duration of operation was also significantly shorter in the study group compared to control (53.1 ± 18.8 min vs. 62.3 ± 20.6 min; P < 0.05). No procedural complications were reported in both groups. The irradiation time and exposure dose along with total operation duration was significantly reduced when the Ensite NavX mapping system was used during RFCA in comparison with traditional X-ray fluoroscopy method.