Contrast-enhanced first pass myocardial perfusion imaging: Correlation between myocardial blood flow in dogs at rest and during hyperemia

摘要: The sensitivity of contrast-enhanced MR first pass perfusion imaging in detection and quantification hypoperfused myocardium was evaluated using an instrumented, closed-chest dog model where graded regional hypoperfusion induced by applying predetermined levels stenosis to the left anterior descending artery (LAD). All measurements were performed at rest under stress dipyridamole (DIP). Myocardial assessed both with radiolabeled microspheres injected immediately before administration contrast agent. Ultrafast a Turbo FLASH sequence 180 degrees inversion prepulse. A Gd-DTPA bolus into atrium T1-weighted images acquired every heart beat. Signal intensity measured from regions LAD circumflex (LCx) beds plotted against time generate signal versus curves (SI curve). Various flow indices derived according indicator dilution theory, compared without volume correction due vasodilation myocardial blood (MBF) calculated microspheres. Correlation MBF data demonstrated that different transmural can be easily visualized accurately monitored SI curves. Detection impairment improved significantly after DIP. inverse mean transit curve found yield linear correlation absolute microsphere data. These results suggest intracardiac injections exogenous agent, parametrically enhanced ultrafast MRI.