Validation of a novel three-dimensional ultrafast cardiac magnetic resonance imaging protocol in adolescents: a non-inferiority study compared with the two-dimensional gold standard

BACKGROUND: Cardiac magnetic resonance (CMR) is the gold standard for assessing cardiac anatomy and function. However, long acquisition times and multiple breath-holds pose significant challenges in pediatric imaging. OBJECTIVE: To perform a non-inferiority analysis comparing a novel 3-dimensional (D) ultrafast CMR protocol against the conventional 2-dimensional (D) gold standard for evaluating cardiac function, strain, and tissue characterization in adolescents. MATERIALS AND METHODS: Thirty-nine adolescents (mean age 12.2±2.6 years) underwent both a standard 2-D protocol and a 3-D ultrafast protocol at 3-T. The 3-D protocol comprised enhanced sensitivity encoding by static outer volume subtraction (ESSOS) cine and 3-D late gadolinium enhancement. Image quality and diagnostic confidence were compared. A pre-specified non-inferiority margin (Δ) was used to assess functional and strain parameters. Agreement was evaluated using Bland-Altman analysis and intraclass correlation coefficients (ICCs). RESULTS: The total scan time was significantly shorter for the 3-D protocol compared to the 2-D protocol (75.8±10.0 s vs. 734.4±19.6 s, P<0.05). Image quality scores were comparable between protocols (median score 4.0, P=0.74). The 3-D protocol demonstrated statistical non-inferiority for all functional and strain metrics. Bland-Altman analysis showed minimal bias for key parameters, and the 95% confidence intervals for differences met the pre-specified non-inferiority margins. Intraclass correlation coefficients (ICCs) indicated good to excellent agreement for all parameters (n=39). CONCLUSION: The novel 3-D ultrafast CMR protocol is non-inferior to the conventional 2-D gold standard for quantitative assessment of cardiac function and strain in adolescents. It offers comparable image quality with significantly reduced acquisition times, potentially improving clinical feasibility in pediatric populations.