Feasibility and safety of cavotricuspid isthmus ablation using exclusive intracardiac echocardiography guidance: a proof-of-concept, observational trial

Abstract

IntroductionCatheter ablation is the preferred treatment for typical atrial flutter (AFl), but it can be challenging due to anatomical abnormalities. The use of 3D electroanatomical mapping systems (EAMS) has reduced fluoroscopy exposure during AFl ablation. Intracardiac echocardiography (ICE) has also shown benefits in reducing radiation exposure during AFl ablation. However, there is a lack of evidence on the feasibility of ICE-guided, zero-fluoroscopy AFl ablation without the use of EAMS.MethodsIn this prospective study, we enrolled 80 patients with CTI-dependent AFl. The first 40 patients underwent standard fluoroscopy + ICE-guided ablation (Standard ICE group), while the other 40 patients underwent zero-fluoroscopy ablation using only ICE (Zero ICE group). Procedure outcomes, including acute success, procedure time, fluoroscopy time, radiation dose, and complications, were compared between the groups.ResultsThe acute success rate was 100% in both groups. Out of the 40 cases, the zero-fluoroscopy strategy was successfully implemented in 39 cases (97.5%) in the Zero ICE group. There were no significant differences in procedure time [55.5 (46.5; 66.8) min vs. 51.5 (44.0; 65.5), p = 0.50] and puncture to first ablation time [18 (13.5; 23) min vs. 19 (15; 23.5) min, p = 0.50] between the groups. The Zero ICE group had significantly lower fluoroscopy time [57 (36.3; 90) sec vs. 0 (0; 0) sec, p < 0.001] and dose [3.17 (2.27; 5.63) mGy vs. 0 (0; 0) mGy, p < 0.001] compared to the Standard ICE group. Total ablation time was longer in the Standard ICE group [597 (447; 908) sec vs. 430 (260; 750), p = 0.02], but total ablation energy [22,458 (14,836; 31,116) Ws vs. 17,043 (10,533; 29,302) Ws, p = 0.10] did not differ significantly. First-pass bidirectional conduction block of the CTI and acute reconnection rates were similar between the groups. No complications or recurrences were observed during the follow-up period.ConclusionOur study suggests that zero-fluoroscopy CTI ablation guided solely by ICE for AFl is feasible and safe. Further investigation is warranted for broader validation.

Local impedance and contact force guidance to predict successful cavotricuspid isthmus ablation with a zero-fluoroscopy approach

“…In the last years, guidance by ICE has demonstrated reducing not only fluoroscopy times but also ablation and procedure times ( 31 ) and allowing successful ablation in some challenging cases ( 32 ). More recently, zero-fluoroscopy guided exclusively by ICE has been described in two studies ( 10 , 33 ) as an effective and safe approach, without impacting procedural times and helping to recognize early potential complications. Thus, ICE could constitute a valuable alternative for zero-fluoroscopy CTI ablation, but further and larger studies are needed to confirm these preliminary findings.…”

“…Given that there is a definite risk of cancer induction ( 7 ) and no minimum safe threshold dose, the radiation dose should be reduced to the lowest possible following the ALARA principle (As Low As Reasonably Achievable). As a matter of fact, the awareness of the ionizing radiation risks has led many electrophysiologists to erase the use of X-rays, by implementing zero-fluoroscopy procedures guided by electroanatomical navigation systems ( 8 , 9 ) and more recently, intracardiac echocardiography (ICE) ( 10 ).…”

“…Several studies and large meta-analyses have proven the feasibility, efficacy and safety of a zero/minimal fluoroscopy approach during supraventricular arrhythmias RFCA, reducing radiation exposure and ablation time (8)(9)(10)(11)(12). This non-fluoroscopic workflow also benefits health care professionals, minimizing their accumulated radiation dose and reducing the risk of developing severe spinal injuries related to wearing lead aprons (13,14).…”

Intracardiac Echocardiography: An Invaluable Tool in Electrophysiological Interventions for Atrial Fibrillation and Supraventricular Tachycardia

“…Two studies have investigated the feasibility and safety of zero-fluoroscopy CTI ablation under the guidance of ICE alone [ 94 , 95 ]. Luani et al .…”

“…Debreceni et al . [ 94 ] conducted a comparative study and reported a significant reduction in CTI ablation time under the sole guidance of ICE. The procedure time, puncture-to-first-ablation time, and total ablation energy in the ICE-guided group were similar to those in the fluoroscopy + ICE-guided group [ 94 ].…”