Development and Use of an X-ray Induced Fluorescence System Designed to Measure Regional Myocardial Perfusion.

摘要

The need to measure myocardial perfusion noninvasively, both for clinical and for research purposes, has resulted in the development of several measurement techniques. In the present work, an attempt was made to produce a system for measuring regional myocardial perfusion based on X-ray induced fluorescence of an iodinated flow tracer. The system's development concentrated on the need to measure accurately the tracer concentration transients which would arise in an intact heart after a tracer's intravenous injection. The subsequent analysis of these transients was also developed here in order to provide a quantitative measure of bloom perfusion based on a mathematical model of tracer transport through the coronary vasculature. An evaluation of the system's ability to produce accurate measurements of regional myocardial perfusion in vivo was also undertaken. In 13 open-chested canines, X-ray induced fluorescence was used to monitor the iodine concentration transients which arose in the left ventricular lumen and in a discrete region of the myocardium after an intravenous injection of iodinated flow tracer. Deconvolution of the recorded transients in the frequency domain produced a transfer function from which the mean transit for the tracer to travel from the left ventricular lumen to the myocardium was calculated.