Dynamics of intramural and transmural reentry during ventricular fibrillation in isolated swine ventricles

Miguel Valderrábano, Moon Hyoung Lee, Toshihiko Ohara, Angela C. Lai, Michael C. Fishbein, Shien-Fong Lin, Hrayr S. Karagueuzian, Peng Sheng Chen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

114 Scopus citations


The intramural dynamics of ventricular fibrillation (VF) remain poorly understood. Recent investigations have suggested that stable intramural reentry may underlie the mechanisms of VF. We performed optical mapping studies of VF in isolated swine fight ventricles (RVs) and left ventricles (LVs). Nine RV walls were cut obliquely in their distal edge exposing the transmural surface. Six LV wedge preparations were also studied. Results showed that intramural reentry was present. In RV, 28 of 44 VF episodes showed reentry; 15% of the activation pathways were reentrant. Except for 4 episodes, reentry was transmural, involving subendocardial structures as the papillary muscle (PM) or trabeculae. In LV, reentry was observed in 27 of 27 VF episodes; 23% of the activations were part of reentrant pathways (P<0.05 compared with RV). All LV reentrant pathways were truly intramural (confined to the wall) and were frequently located at the PM insertion. In both ventricles, reentry was spatially and temporally unstable. Histological studies showed abrupt changes in fiber orientation at sites of reentry and wave splitting. Connexin 40 immunostaining demonstrated intramyocardial Purkinje fibers at sites of reentry in the PM root and around endocardial trabeculae. Our results confirm that reentry is frequent - but unstable - in the myocardial wall during VF. In RV, reentry is mostly transmural and requires participation of subendocardial structures. The LV has a greater incidence of reentry and is intramural. Anisotropic anatomic structures played key roles in the generation of wave splitting and in the maintenance of reentry.

Original languageEnglish
Pages (from-to)839-848
Number of pages10
JournalCirculation Research
Issue number8
StatePublished - 27 Apr 2001


  • Anisotropy
  • Fibrillation
  • Intramural reentry
  • Papillary muscle
  • Purkinje


Dive into the research topics of 'Dynamics of intramural and transmural reentry during ventricular fibrillation in isolated swine ventricles'. Together they form a unique fingerprint.

Cite this