A cardiac gated acquisition of MR data during a breath-hold employs a hybrid PR pulse sequence to acquire projection views from which image frames may be reconstructed at a plurality of cardiac phases during each heartbeat. Composite images are reconstructed at each cardiac phase using interleaved projection views acquired during all the heartbeats. The composite images are used to reconstruct the highly undersampled image frames at the same cardiac phase using a highly constrained backprojection method.