Introduction: Pulmonary vein isolation (PVI) is an established procedure to treat atrial fibrillation (Afib) but it increases periinterventional thromboembolic burden (1). Literature provides ambiguous results about ablation effects on different hemostatic markers. The aim of this study was to assess the difference between two used PVI methods (cryoablation and radiofrequency ablation (RFA)) in postinterventional platelet reactivity (PR).
Patients and Methods: We analyzed PR in 168 consecutive patients undergoing PVI due to Afib in our institution using Multiplate function analyzer. Blood samples for PR measurements were drawn prior to the procedure and the on the following morning. In total, 123 and 45 patients underwent cryoablation and RFA, respectively. There was no difference in demographics and baseline platelet parameters between the groups (Table 1). ASPItest, ADPtest and TRAPtest were used as assays for the quantitative in vitro determination of PR triggered by arachidonic acid, adenosine diphosphate and thrombin receptor activating peptide-6, respectively.
Results: Postprocedurally, PR was significantly lower in both groups after 24 hours. There were no statistically significant differences in PR values between the groups on the next day in all three tests (ASPItest 23U v 25U p=0.75; ADPtest 20U v 25U p=0.24; TRAPtest 29U v 34U p=0.47) (Figure 1).
Conclusion: Our results show that PR after PVI is lower after 24 hours regardless of the type of ablation. Insignificantly lower PR in cryo group might be due to less myocardial necrosis done with cryo compared to RFA. We hypothesize that the general similarity in PR drop could be predominantly a result of successful restoration of sinus rhythm in both groups which might be the prevailing factor in determining PR level in patients with Afib one day after ablation. These results should be confirmed with studies which would encompass early and late periinterventional PR measurements on a larger cohort of patients.