Endocardial Ablation
Standalone endocardial catheter ablation is less invasive than surgical
concomitant ablation and involves a catheter being guided through venous
access points, entering the right atrium, and ultimately the left atrium
where the endocardial ablation is performed. Patients with paroxysmal AF
have higher success rates, such as freedom from atrial arrhythmias and
less recurrences of repeat ablations compared to those with
non-paroxysmal AF. After a secondary repeat ablation, paroxysmal AF
patients experienced over 92% freedom from AF, whereas patients with
persistent AF and long-standing persistent AF had lower secondary
success rates of 88.1 and 80.9%,
respectively.14 In a
single center study, long-term success rates ranged from 28.4 to 51.1%
recurrence-free rates after a single or three procedures, respectively,
leaving a large percentage of patients with failed
treatment.15 While
contemporary trials have demonstrated that radiofrequency catheter and
cryoballoon endocardial ablation may yield sufficient clinical outcomes
for paroxysmal AF and even non-paroxysmal AF without advanced substrate,
there are patients with advanced AF who tend to be more difficult to
treat and have lower success rates and consequently more subsequent
procedures after endocardial
ablation.14 Recent
studies of persistent AF have demonstrated rates of effectiveness of
54.8% to 61.7% at 12 and 15 months, respectively, after a single
ablation
procedure.16,17Tsai et al. recently published longer term follow up results from a
Taipei hospital. After a single index ablation procedure, 100 patients
with non-paroxysmal AF were followed very-long-term for over 5 years
with a target follow up of 10 years. Only 16% of patients remained free
of AF at 10 years, with the majority of AF recurrence (61.9%) at the
one year mark, emphasizing the need for more effective and enduring
treatment options for non-paroxysmal
AF.18