Study Population
From September 2016 to April 2017, 60 consecutive patients underwent
two-staged hybrid ablation at Anthea Hospital, GVM Care&Research, Bari,
Italy and were followed-up for 1 year to monitor recurrences. Patients
were included on the basis of the following criteria: (A) symptomatic
LSPAF as defined by current guidelines(9), (B) AF refractory to the
maximal tolerated doses of antiarrhythmic therapy, and (C) at least 1
failed electrical or pharmacologic cardioversion attempt during the 6
months preceding the surgical evaluation. Left atrial dimension indexed
to body surface area exceeding 35 mm/m2 was considered
an exclusion criterion.
The study was designed as a two-arm non randomized interventional study.
All enrolled patients underwent epicardial isolation of the pulmonary
veins and of the left atrial posterior wall (“box lesion”). In the
interventional cohort (BB group, 30 patients), additional surgical
ablations targeting the BB was performed. For comparison, BB group
patients’ outcomes were compared with the conventional cohort (CONV
group) comprising 30 consecutive patients who underwent the same
surgical lesions without BB ablation.
All patients underwent a staged endocardial ablation within 6 weeks
after the surgical procedure with the goal of verifying or ablating: (A)
the surgical lines and completing the isolation if needed, (B)
additional right and left atrial substrate modification and (C) other
triggers of AF. Each ablation strategy was performed by the same
operators in both groups. All procedures were performed by expert
operators, with >10 years of experience both parts of the
staged procedure, to correct for a potential learning curve effect. GVM
Care&Research ethical board approved the study and all patients gave
written informed consent for procedure and study enrollment.