Extent of myocardial collateralization: determination with three-dimensional elastic-subtraction spiral CT.

Abstract

This study was undertaken to develop a standard that can be used to assess new high-resolution collateral zone imaging methods. The authors performed ex vivo helical CT in seven pig hearts after microsphere studies of blood flow and coronary angiography. They compared the zones of collateralization depicted at CT and at microsphere studies. The extent of the collateral zone at CT, computed by using elastic subtraction, correlated well with the coronary blood flow distribution determined with microsphere analysis (r = .95). The root-mean-square error was 6.5%, which indicates good agreement. Accurate assessment of collateralization extent has become an important goal because of the discovery of agents that stimulate the growth of coronary collateral vessels. The precision of elastic-subtraction CT and its validation with respect to the blood flow distribution at microsphere analysis indicate that elastic-subtraction CT can serve as a standard for the measurement of collateralization extent.