Tailored Atrial Substrate Modification Based on Low-Voltage Areas in Catheter Ablation of Atrial Fibrillation

Abstract

Background-Reduced electrogram amplitude has been shown to correlate with diseased myocardium. We describe a novel individualized approach for catheter ablation of atrial fibrillation (AF) based on low-voltage areas (LVAs) in the left atrium (LA). We sought to assess (1) the incidence of LVAs in patients undergoing AF catheter ablation, (2) the distribution of LVAs within the LA, and (3) the effect of an individualized ablation strategy on long-term rhythm outcomes. Methods and Results-In 178 patients with paroxysmal or persistent AF, LA voltage maps were created during sinus rhythm after circumferential pulmonary vein isolation. Subsequent substrate modification was confined to the presence of LVA (<0.5 mV) and inducible regular atrial tachycardias. LVAs were identified in 35% and 10% of patients with persistent and paroxysmal AF, respectively. The LA roof and the anterior, septal, and posterior wall LA were most often affected. The 12-month atrial tachycardias/AF-free survival was 62% for patients without LVAs and 70% for patients with LVAs and tailored substrate modification (P=0.3). Success rate in a comparison group of 26 LVA patients without further substrate modification was 27%. Conclusions-LVAs can be found at preferred sites in 10% of patients with paroxysmal AF and in 35% of patients with persistent AF. This is the first clinical report describing a consistent voltage-based approach for substrate modification in addition to circumferential pulmonary vein isolation irrespective of AF type. Application of this limited individualized approach may have the potential to compensate for the impaired 12-month outcome of patients with endocardial structural defects. (Circ Arrhythm Electrophysiol. 2014;7:825-833.)

2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS

“…Dlatego u pacjentów z przetrwałym AF ablacja złożonych frakcjonowanych elektrogramów, ablacja rotorów, rutynowe wykonywanie liniowych uszkodzeń lub inne dodatkowe ablacje nie wydają się uzasadnione podczas pierwszego zabiegu [735,738,739]. Dodatkową ablację jako uzupełnienie całkowitej PVI [716] można natomiast rozważyć u pacjentów z nawrotami AF po początkowym zabiegu ablacji [719,740,741]. U pacjentów z udokumentowanym trzepotaniem zależnym od cieśni trójdzielno-żylnej, u których wykonuje się ablację AF, zaleca się ablację cieśni.…”

Ablation of long-standing persistent atrial fibrillation

“…Rolf et al correlated low voltage areas in LA (<0.5 mV) to LA scarring and found a higher scar burden amongst patients with persistent AF (35%) compared to the patients with paroxysmal AF (10%) (72). They reported a 70% success rate of ablation with targeting of LA substrate with low voltage areas in addition to PVI, in comparison to only 26% in patients where PVI was the sole target.…”

Possible Benefits of Direct Oral Anticoagulants for the Electrophysiological Substrate Properties of Atrial Fibrillation: Can these New Agents have Antiatrial Fibrillation Actions?

“…Furthermore, the correlation between atrial fibrosis and AF maintenance has been reported. Basic and clinical studies suggest the importance of atrial fibrosis as a major contributor to AF maintenance [12,[17][18][19]. According to these data, thrombin and factor Xa are suggested to play significant roles in the progression of the AF substrate.…”

“…Furthermore, the poor outcomes of PV isolation for nonparoxysmal and long-lasting persistent AF patients with extensive low voltage areas in atria have been reported. Therefore, extensive atrial fibrosis may correlate with the AF progression and may have a [19]. Therefore, the anti-fibrotic actions on the atrium by DOACs can be a potential therapeutic approach to suppress AF progression causing electrical and structural remodeling and for improving the efficacy of catheter ablation.…”