Combined Respiratory & Cardiac Triggered MRA of Congenital Heart Disease with a Blood Pool Contrast Agent

Shreyas S. Vasanawala¹, Frandics P. Chan¹, Beverley Newman¹, Marcus T. Alley¹

Pediatric cardiovascular MRI is degraded by cardiac pulsation and respiratory motion. An SPGR sequence was modified to enable combined cardiac/respiratory triggering and fractional acceleration. 23 pediatric patients undergoing MRI with gadofosveset blood pool agent had triggered and non-triggered acquisitions. Anatomic structures were graded by two experienced readers in randomized blinded fashion and compared directly. Triggered images had higher scores for all structures (Wilcoxon rank-sum test, p<0.05). Triggered images were more likely to be preferred for most structures (one-sided binomial test, p<0.05). The approach enables imaging without suspended respiration, thus reducing depth of anesthesia and need for an artificial airway.