Role of papillary muscle in the generation and maintenance of reentry during ventricular tachycardia and fibrillation in isolated swine right ventricle. Academic Article uri icon

Overview

abstract

  • BACKGROUND: The role of papillary muscle (PM) in the generation and maintenance of reentry is unclear. METHODS AND RESULTS: Computerized mapping (477 bipolar electrodes, 1.6-mm resolution) was performed in fibrillating right ventricles (RVs) of swine in vitro. During ventricular fibrillation (VF), reentrant wave fronts often transiently anchored to the PM. Tissue mass reduction was then performed in 10 RVs until VF converted to ventricular tachycardia (VT). In an additional 6 RVs, procainamide infusion converted VF to VT. Maps showed that 77% (34 of 44) of all VT episodes were associated with a single reentrant wave front anchored to the PM. Purkinje fiber potentials preceded the local myocardial activation, and these potentials were recorded mostly around the PM. When PM was trimmed to the level of endocardium (n = 4), sustained VT was no longer inducible. Transmembrane potential recordings (n = 5) at the PM revealed full action potential during pacing, without evidence of ischemia. Computer simulation studies confirmed the role of PM as a spiral wave anchoring site that stabilized wave conduction. CONCLUSIONS: We conclude that PM is important in the generation and maintenance of reentry during VT and VF.

publication date

  • September 28, 1999

Research

keywords

  • Papillary Muscles
  • Tachycardia, Ventricular
  • Ventricular Fibrillation
  • Ventricular Function, Right

Identity

Scopus Document Identifier

  • 0033613142

Digital Object Identifier (DOI)

  • 10.1161/01.cir.100.13.1450

PubMed ID

  • 10500048

Additional Document Info

volume

  • 100

issue

  • 13