Blood damage, platelet and clotting activation during application of radiofrequency or cryoablation catheters: A comparative in vitro study

During catheter ablation of cardiac tissue, the insulting stimulus may dama ge and activate the blood. Specifically activation of platelets and the clo tting system is a potential risk by their formation of thrombi. In this stu dy the effect of two different techniques, a radiofrequency and a cryo-appl ication procedure, on the activation of platelets and clotting in an in vit ro blood circulation model was investigated. The radio-frequency procedure induced significantly more blood cell damage, platelet activation and clott ing than did the cryo-application procedure. Macroparticles were circulatin g in blood after the radiofrequency procedure. In the cryo procedure, blood damage was limited to the frozen blood spherule around the tip of the cath eter. It is concluded that at least in those circumstances where blood is d irectly contacting the tip of the radiofrequency or cryo-application cathet er, the latter is more safe with regard to thrombus formation.