Radiofrequency catheter ablation of atrial flutter induces the release of platelet and leukocyte-derived procoagulant microparticles and a prothrombotic state.

Background: To assess the extent of endothelium, platelet, and leukocyte damage and coagulation activation induced by radiofrequency catheter ablation (RF) of atrial flutter. In the vasculature, procoagulant microparticles (MPs) are reliable markers of vascular damage. They provide an additional phospholipidic surface, enabling the assembly of the enzyme complexes of blood coagulation and consequent thrombin generation. Methods: MPs were measured in the venous blood of 33 patients with isthmus-dependent atrial flutter undergoing RF before (RF0), immediately after (RF1), and at day 1 (RF2) thereafter. Concentrations of PAI-1, vWF, and D-dimers were simultaneously determined. MPs procoagulant activities were determined using a functional prothrombinase assay. RF induces an early rise of platelet-derived MPs (platelet), vWF Ag, and D-dimers levels, which is concomitant with the decrease of PAI-1 concentrations. Conversely, no significant changes in endothelial-derived MPs could be evidenced. At RF2, sustained elevation of leukocytes-derived MPs, vWF, and D-dimers testified to an ongoing prothrombotic status. Conclusion: RF ablation of common flutter induces a prothrombotic state and the release of platelet and leukocyte-derived procoagulant microparticles. Whereas this activation of blood coagulation could be viewed as clinically marginal in right-sided procedures, its relevance in left-sided procedures should be established.