Semiquantitation of regional myocardial blood flow in normal human subjects by first-pass magnetic resonance imaging.

The purpose of this study was to investigate the feasibility of first-pass MR imaging for measurement of regional myocardial blood flow in human beings. The first pass of the contrast agent Gd-DTPA through the myocardium was imaged in 12 normal volunteers with an ECG-gated Turbo-Flash sequence. The MTT of the contrast agent through the myocardium after a bolus injection was derived from curves of SI versus time. The bolus was injected through an intravenous catheter, which was advanced to the central venous position (preferably the right atrium). To investigate myocardial input function, different bolus concentrations and catheter positions were compared. It is concluded that first-pass MR imaging is feasible in human subjects when a central injection of 0.03 mmol/kg of Gd-DTPA is applied. MTT values were similar throughout the myocardium of normal subjects at rest, reflecting normal perfusion. Absolute values of MTT were related to the myocardial input.