Basic/Translational Science -> Whole Animal Electrophysiology and Pharmacology (includes Neurohumoral Modulation) D-PO05 - Poster Session V (ID 39) Poster

D-PO05-052 - Epi- And Endocardial Mapping Of Ventricular Fibrillation During Acute Myocardial Infarction In A Porcine Model (ID 522)

 S.M. Sattler: Nothing relevant to disclose.


Background: Ventricular fibrillation (VF) in the early phase of acute myocardial infarction (AMI) is one of the most frequent causes of sudden cardiac death.
Objective: Aim was the development of a porcine model of AMI and spontaneous VF with electrical mapping using non-contact mapping (EnSite Array) in the left ventricle (LV) and an electrode sock covering the whole heart. Activation-recovery intervals (ARI), beat-to-beat variation in repolarization (BVR), and ectopic activation were measured.
Methods: Sixteen Danish Landrace pigs (56±4 kg) were anaesthetized and equipped with the multi electrode array (St. Jude, EnSite Array) catheter in the LV. The sock electrode was placed on the pericardium covering the whole heart. Finally, the mid-left anterior descendent artery was occluded with a balloon to induce AMI and kept in place for 45 minutes followed by reperfusion.
Results: Spontaneous VF occurred in 7/16 pigs during the occlusion period. Epi- and endocardial mapping showed similar shortening of ARI in the infarcted area (figure 1A). AMI shortened ARI in the ischemic area to a greater extend in pigs that developed VF (figure 1B) and caused beat-to-beat variation in repolarization (BVR; figure 1C). Ectopic beats proceeding spontaneous VF varied in activation site and subsequent repolarization (figure 1D, left). Multiple short-coupled ectopic beats destabilized the electrical substrate further (figure 1D, last 4 beats).
Conclusion: Pigs with VF had shorter ARI, greater dispersion but similar BVR during AMI. These findings provide a deeper understanding of arrhythmogenesis during AMI and can help to develop new antiarrhythmic drugs or to assess risk factors of VF.