Chronic skeletal muscle ischemia in rats decreases the inducibility of ventricular tachyarrhythmias after myocardial infarction

In Vivo. 2011 Sep-Oct;25(5):781-6.

Abstract

Background: Chronic hind-limb ischemia confers cytoprotection after coronary occlusion, but it is unclear whether it ameliorates substrate formation for ventricular tachyarrhythmias (VTs).

Materials and methods: Chronic hind-limb ischemia was generated by femoral artery excision in 50 rats, while 25 animals were sham-operated. Left coronary artery ligation was performed after 3 weeks and infarct size was measured 24 hours thereafter. The inducibility of VTs was assessed by programmed electrical stimulation (PES) 4 weeks post-ligation. A score was assigned, based on protocol stage and tachyarrhythmia duration. Monophasic action potentials (MAP) were recorded prior to and 4 weeks after ligation.

Results: The infarct size was smaller (p=0.000079) in the ischemic rats (25.7±2.1%) than in the controls (41.7±2.2%), accompanied by a lower (p=0.029) arrhythmia score (1.05±0.38 versus 2.70±0.68, respectively). The action potential duration (APD) was shorter (p<0.05) in the ischemic rats prior to ligation and remained stable after 4 weeks.

Conclusion: Chronic hind limb ischemia limits infarct size and decreases inducible ventricular tachyarrhythmias.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Animals
  • Electrocardiography
  • Heart Rate
  • Hindlimb / blood supply*
  • Ischemic Preconditioning*
  • Muscle, Skeletal / blood supply*
  • Myocardial Infarction / complications*
  • Myocardial Infarction / pathology
  • Myocardial Reperfusion Injury / complications*
  • Myocardium / pathology
  • Rats
  • Rats, Wistar
  • Tachycardia, Ventricular / etiology
  • Tachycardia, Ventricular / prevention & control*