1. A magnetic resonance imaging (MRI) system comprising: an MRI gantry including a static magnet, gradient magnet coils and at least one radio frequency (RF) coil defining a patient imaging volume into which a chest region of a patient is located; and RF receiver and transmitter circuits coupled to said at least one RF coil; control circuits connected to said gantry and to said RF receiver and transmitter circuits, said control circuits having an operator display and an operator control input port for configuring and operating said MRI system to acquire and process MRI data from said patient, said control circuits being configured (i) to acquire first, second and third MRI data sets for a same region within the chest region without use of a contrast-enhancing chemical agent by performing the following three data acquisition sub-sequences within one scan sequence, (A) using a non-selective inversion pulse without a selective inversion pulse, (B) using a non-selective inversion pulse and a selective inversion pulse, and (C) using a selective inversion pulse without a non-selective inversion pulse; (ii) to repeat the acquisition of said first, second and third MRI data sets for each of plural different black blood time to inversion (BBTI) values, wherein three data acquisition sub-sequences are performed respectively for a same BBTI value; (iii) image processing circuits configured to generate first, second and third images for the same region for each of plural different BBTI values based on the first, second and third MRI data sets and to generate a processed cardiac perfusion image by differentially combining respectively corresponding pixels of the first, second and third images; and (iv) an output circuit for outputting said processed cardiac perfusion image for digital storage or digital data transmission.