Gadopiclenol for Cardiac MRI: Comparison of Myocardial T1 Relaxation Times and Subjective Image Quality at Different Doses in Patients With Anderson-Fabry Disease.

OBJECTIVES: Due to its high relaxivity, the second-generation gadolinium-based contrast agent gadopiclenol has been shown to provide equally high image quality with reduced gadolinium dose. Gadopiclenol has not yet been approved for cardiac magnetic resonance imaging (CMR). The aim of this observational feasibility study was to assess late gadolinium enhancement (LGE) image quality and myocardial T1 shortening after application of gadopiclenol at 2 dose levels in patients with Anderson-Fabry disease (AFD) undergoing 3 T CMR. MATERIALS AND METHODS: In this retrospective single-center study, 133 CMR examinations were screened, and 32 patients met the eligibility criteria of AFD, gadopiclenol administration, documented contrast dose, and complete precontrast and postcontrast T1 mapping. Patients were grouped by dose (0.05 mmol/kg group, ranging from 0.04 to 0.07 mmol/kg vs. 0.1 mmol/kg group, ranging from 0.08 to 0.11 mmol/kg; n=16 each). Three readers independently rated LGE image quality using a 5-point Likert scale. Quantitative analysis included precontrast and postcontrast myocardial T1, ΔT1, and the relaxation rate ΔR1. Segment-level postcontrast effects were analyzed using a mixed-effects model adjusting for acquisition delay. RESULTS: Both dose levels, the 0.05 mmol/kg and the 0.1 mmol/kg gadopiclenol, resulted in diagnostic examinations with high subjective LGE image quality. The 0.1 mmol/kg group showed slightly higher ratings for overall image quality and bloodpool-to-myocardium contrast, although absolute differences were small and most examinations in the 0.05 mmol/kg group were still rated good to excellent. Native myocardial T1 did not differ between groups (1132.39±61.91 ms vs. 1132.84±53.39 ms; P=0.98). Postcontrast T1 shortening was greater at 0.1 mmol/kg. In segment-level analysis, the higher dose showed greater ΔR1 in all segments, which was statistically significant in unaffected segments (Δ=-0.37 1/s; P=0.003), but not in affected segments (Δ=-0.18 1/s; P=0.48). CONCLUSIONS: In this retrospective 3 T AFD cohort, gadopiclenol provided high LGE image quality at both dose levels. While 0.1 mmol/kg produced slightly stronger qualitative and quantitative contrast effects, 0.05 mmol/kg remained technically feasible. These preliminary findings support that dose reduction to 0.05 mmol/kg gadopiclenol may be feasible in CMR. However, validation through prospective studies is needed before recommending lower-dose gadopiclenol broadly in routine CMR.