How does the effective refractory period in the epicardial and endocardial layers correlate with surface T-waves, and how is it affected by acute coronary ligation in a dog model?
This experimental study demonstrates that the polarity of surface T-waves correlates with transmural differences in the effective refractory period, which is significantly altered by acute ischemic injury.
The effective refractory period was determined at the surface and in the deeper layers of the dog heart and was correlated with the surface T-waves. A small delay in recovery of cardiac excitability appeared at the surface when T-waves were negative and in the deeper layers when T-waves were positive. Acute injury produced by ligation of the coronary artery caused a marked acceleration of recovery in the deeper layers, sometimes extending to the surface.
Reynolds et al. (Sun,) studied this question.