further , recent experience with an experimental standardized , gas-producing contrast agent in an open chest animal model with an experimentally produced ventricular septal defect suggests that a combination of an experimental right heart agent that produces a measurable and reproducible amount of contrast effect , with a videodensitometric system capable of quantifying both positive and negative contrast effects , may provide an ultrasonic method for evaluating the magnitude of cardiac shunts .
C0817096
chest
C0018818
ventricular septal defect