Non-fluoroscopic catheter ablation: A randomized trial

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.

Fluoroless Catheter Ablation of Atrial Fibrillation: Integration of Intracardiac Echocardiography and Cartosound Module

Objective

To evaluate the feasibility, safety, and clinical efficacy of non-fluoroscopic radiofrequency catheter ablation of atrial fibrillation (AF) in comparison to traditional fluoroscopy-guided ablation in a local Canadian community cohort.

Methods

We retrospectively studied consecutive patients with paroxysmal and persistent AF undergoing pulmonary vein isolation (PVI) guided by intracardiac echocardiography (ICE) and Carto system (CartoSound module). ICE-guided PVI without fluoroscopy (Zero-fluoro group) was performed in 116 patients, and conventional fluoroscopy-guided PVI (Traditional group) was performed in 131 patients.

Results

Two hundred and forty-seven patients with AF (60.7% male; mean age: 62.2 ± 10.6 years; paroxysmal AF =63.1%) who underwent PVI were studied. Mean procedure times were similar between both groups (136.8±33.4 minutes in the zero-fluoro group vs. 144.3±44.9 minutes in the traditional group; p=0.2). Acute PVI was achieved in all patients. Survival from early AF recurrence was 85% and 81% in the zero-fluoro and traditional groups, respectively (p = 0.06). Survival from late AF recurrence (12-months) between the zero-fluoro and traditional groups was also similar (p=0.1). Moreover, there were no significant differences between complication rates, including hematoma (p = 0.2) and tamponade (p = 1),between both groups.

Conclusions

Zero-fluoroscopy ICE and CartoSound-guided AF ablation may be safe and feasible in patients undergoing PVI compared to conventional fluoroscopy-guided ablation.

Supraventricular Tachycardia in Pregnancy: Gestational and Labor Differences in Treatment

Supraventricular tachycardia (SVT) is a tachyarrhythmia characterized by a heart rate above 120 beats per minute (BPM). Patients with SVT exhibit the following symptoms: palpitations, shortness of breath, chest pain, hemodynamic instability, or possibly asymptomatic. The increase in cardiac output and the increase in resting heart rate during pregnancy predispose pregnant women to SVT. The management of SVT in pregnancy, although remarkably similar, varies slightly based on the trimester of pregnancy. Atenolol and verapamil are effective methods of treating SVT, which can be used during the second and third trimesters. Both medications are contraindicated in the first trimester. At the same time, intravenous adenosine can be used in all three trimesters, including labor. Electrical cardioversion is an effective treatment method for hemodynamically unstable or drug-refractory patients, which has proven to be safe in all three trimesters, including labor but can result in pre-term labor in the third trimester. Non-fluoroscopic ablation proved to be the only treatment method that definitively resolved SVT without recurrence.

Zero fluoroscopy approach versus fluoroscopy approach for cardiac arrhythmia ablations: A systematic review and meta-analysis

BACKGROUND

Radiofrequency catheter ablation for cardiac arrhythmias has traditionally been guided by fluoroscopy. Fluoroscopy exposes the patient, operator, and staff to ionizing radiation which has no safe dose void of stochastic and deterministic biologic risks. Zero fluoroscopy (ZF) approaches for catheter ablation have been advocated to eliminate these risks. We conducted a meta-analysis comparing acute procedure success, recurrence-free survival, complications, and procedure times between the approaches.

METHODS

We conducted a literature search from inception through December 2020 in the databases of EMBASE and MEDLINE. We included randomized controlled trials and cohorts that compared the outcomes of interest in ZF and conventional/low fluoroscopy (CF/LF) approaches. The outcomes sought were acute procedure success, recurrence-free survival, complications, and procedure times. Effect estimates were combined, using the random-effects, generic inverse variance method of DerSimonian and Laird.

RESULTS

Sixteen studies from 2013 to 2020, including 6052 patients (2219 ZF, 3833 CF/LF) were included. There were no significant differences in acute procedure success rate (odds ratio [OR]: 1.10, 95% confidence interval [CI]: 0.75-1.59), recurrence-free survival (OR: 1.08, 95% CI: 0.78-1.49), periprocedural complication rate (OR: 0.72, 95% CI: 0.45-1.16), or total procedure time (weighted mean difference 2.32 min, 95% CI: -2.85-7.50) between ZF and CF/LF approaches, respectively. Overall, only 1.26% of patients crossed over from ZF to CF/LF arm.

CONCLUSIONS

Periprocedural and postprocedural outcomes with a ZF approach compared favorably with traditional fluoroscopic guidance without increasing procedural times. As comfort with ZF grows, coupled with evolving mapping technologies, this method has potential to become the standard approach for catheter ablation.