Robust myocardial blood oxygen level dependent magnetic resonance imaging with long acting coronary vasodilators

A blood oxygen level dependent (BOLD) magnetic resonance imaging (MRI) method for obtaining one or more coronary dynamic parameters (CDPs) of a subject's cardiovascular system, comprising:

• (a) imaging the subject's cardiovascular system at rest to obtain a rest BOLD image;
• (b) administering to the subject an effective amount of a vasodilator for inducing hyperemic response in the subject, wherein the vasodilator induces an extended vasodilatory state in the subject;
• (c) obtaining a series of BOLD images of the subject's cardiovascular system at two or more time points following the administration of the vasodilator to obtain a plurality of stress images;
• (d) registering each of the plurality of stress images to the rest BOLD image to obtain a plurality of motion-corrected images, thereby obtaining BOLD signals of the two or more time points following the administration of the vasodilator based on the plurality of the motion-corrected images;
• (e) fitting the BOLD signals of the two or more time points following the administration of the vasodilator with a first mathematical model;
• (f) solving for one or more fixed parameters of the first mathematical model to extract the one or more CDPs;
• and
• (g) identifying a diseased territory of the subject's cardiovascular system based on the one or more extracted CDPs relative to a reference value,
• wherein the first mathematical model estimates time-dependent changes of the BOLD signals,
• wherein the method improves sensitivity compared to BOLD MRI obtained in single time point acquisitions, and
• wherein the BOLD signal comprises a transverse relaxation time and the first mathematical model comprises a mono-exponential model, T2(t)=T2o+ΔT2max exp(−t/τ), wherein t is a time point following the administration of the vasodilator, T2(t) is the transverse relaxation time at the t, T2o is a first fixed parameter of the one or more fixed parameters of the mono-exponential model estimating a baseline of the transverse relaxation time, ΔT2max is a second fixed parameter of the one or more fixed parameters of the mono-exponential model estimating a maximum change in the transverse relaxation time from rest, and τ is a third fixed parameter of the one or more fixed parameters of the mono-exponential model estimating a coronary constant, and wherein the one or more CDPs comprises the ΔT2max, ΔT2max/T2o, ΔT2max/τ, or (τ×ΔT2max).