left-to-right shunt

n.
  1. A diversion of blood from the left side of the heart to the right, as through a septal defect.
  2. A diversion of blood from the systemic circulation to the pulmonary circulation, as through a patent ductus arteriosus.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.