Aims: To analyze the clinical value of AF induction in patients treated by second
generation CB for paroxysmal AF.
Methods: Seventy patients underwent isoproterenol challenge after pulmonary vein
isolation to assess AF induction and early PV reconnections (EPVR). Patients without
EPVR were evaluated for premature atrial contraction (PAC) induction; atrial ectopy
was considered frequent (PAC+) if >1/10 cycles or >6/min. After isoproterenol
protocol, rapid atrial pacing (RAP) was performed.
Results: AF induction by isoproterenol occurred only in 3/70 (4%) patients of whom
2/3 (66%) patients with an EPVR of a triggering vein. In the 62 patients without EPVR,
PAC+ occurred in 17 patients (27%). RAP could induce AF in 23/70 (33%) patients. At
a mean follow-up of 11.5 months, there were 11/70 (16%) AF recurrences. There was
no significant difference in the AF recurrence rate in RAP inducible versus noninducible
patients (log-rank p=0.33). A 41% recurrence rate (7/17 patients) was seen in
the PAC+ group with significantly different AF-free survival for PAC+ vs PACpatients
(log rank p < 0.0001). PAC+ was the only independent determinant to predict
AF recurrence after multivariate analysis.
Conclusion: PAC occurrence in response to isoproterenol could predict AF recurrence
after PV isolation by CB, while RAP showed no prognostic implication
