Einfluss der Anpresskraft des Hochfrequenzstromablationskatheters auf die Läsionsbildung und das Auftreten von Koronarstenosen am wachsenden Schweineherz im Langzeitverlauf

Influence of contact force during radiofrequency ablation on lesion formation and appearance of coronary artery stenoses at growing porcine myocardium in a long-term follow-up

by Andreas Hans-Werner Nagel née Arnold
Doctoral thesis
Date of Examination:2024-05-15
Date of issue:2024-05-08
Advisor:PD Dr. David Backhoff
Referee:PD Dr. David Backhoff
Referee:Prof. Dr. Markus Zabel
Persistent Address: http://dx.doi.org/10.53846/goediss-10490

 

 

Files in this item

Name:Doktorarbeit Andreas Nagel Endfassung ohne L...pdf
Size:968.Kb
Format:PDF

The following license files are associated with this item:

Abstract

English

Introduction: Supraventricular tachycardia (SVT) is the most-frequent cardiac arrhythmia in children and adolescents. A first-line therapy for pediatric patients is radiofrequency ablation (RFA). Security and efficiency of RFA depend on several parameters such as contact force (CF) of the catheter-tip on the myocardial tissue. The effects of CF on growing myocardium and on coronary artery stenoses has not been systematically studied yet. Methods: RFA-lesions were placed with either low CF (10 – 20 g) or high CF (40 – 60 g) at defined locations in the heart of 12 young piglets, recording the CF continuously. A coronary angiography was performed prior and after the intervention in order to detect demages and stenoses of coronary arteries caused by RFA. The coronary angiography was repeated in adult animals after 6-months. Afterward, the animals were killed by intracoronal injection of potassium chloride. The hearts were explanted and the lesions could be examinated in view of lesion-volume and coronary artery stenoses. For this purpose a preparation for microscopic examination was needed so that the tissue was excised, fixated and coloured and the lesion-volume was measured in virtual microscopy. In a former study of the research-group, the lesions of 12 piglets were examinated following coronary angiography 48h after RFA. Results: In comparison to the lesions detected 48h after RFA, the volume was significantly smaller after 6 months. Only at the AV-annulus the lesion-volume was significantly higher by using a high CF. In all other locations, there was no significant relation with CF and lesion-volume. Although in 2/12 animals coronary artery stenoses could be detected in a close anatomical relationship to a RFA-lesion, there was no significant relation to CF. Conclusions: Under the experimental conditions in piglets, no significant relation between CF and lesion-volume as well as to coronay artery stenoses could be found. This is in contrast to other experiments and clinical studies concerning RFA in adults, where a clear relation between CF and severe complications such as perforations and coronary artery stenoses was found. On the other hand, low CF seems to be suffcient to induce effective RF-lesions in pediatric patients. The appearance of coronary artery stenoses seems to be primarily dependent on the anatomical relationship to RFA-lesion. In conclusion, recording the CF can be useful in RFA at high-risk locations like a posteroseptal accessory pathway. To evaluate the importance of continuous monitoring of the CF during RFA, further investigations are needed.
Keywords: supraventricular tachycardia; children; electrophysiology; radiofrequency ablation; contact force; lesion-volume
 
Statistik