Rapid Scan Protocol for Neonatal Feed-and-Wrap Cardiovascular Magnetic Resonance in Congenital Heart Disease (RF_SA_501)

Neonatal CMR (Cardiovascular Magnetic Resonance) has traditionally faced two main limitations: (1) need for contrast agents to enhance signal-to-noise ratio (SNR) and improve image quality, (2) requirement for general anesthesia or sedation due to long scan times. Non-contrast, sedation-free, and free-breathing feed-and-wrap CMR utilizes natural sleep induced by feeding and swaddling, along with acceleration advancements that reduce scan times, eliminating the need for anesthesia. Additionally, specialized small body coils and a 3-Tesla MRI scanner significantly improve SNR, making contrast agents unnecessary.

Methods:

Neonatal feed and wrap CMR using an CMR compatible incubator was performed in 82 consecutive neonates with congenital heart disease (CHD) (Fig.1). The free-breathing, non-contrast, and sedation-free protocol included:

• TurboFLASH sequences for standard three-plane localizers


• Compressed Sensing 4D Flow CMR (work in progress) for haemodynamic and structural 3D whole heart assessment (using inherent inflow enhancement as contrast)


• 2D TurboFLASH cine imaging for ventricular function


• T2 SPACE (for lymphatic assessment in single ventricle cases)


• Real-time cine for surgical access

Eighty-two neonatal CMR (46 males) were acquired 2020-2024 (average height, weight and age: 53±6cm, 3.99±1.07kg, 61±61days[range 0-348 days]) (Table 1). Mean CMR scan duration was 25±6min (range 9-40min), with only 10 scans (12%) exceeding 30min (Fig.2).Longer scans occurred in single ventricle pre-Glenn assessments requiring T2 SPACE sequences for lymphatic assessment, and in complex CHD. One scan failed due to the patient waking up at the start. 4D Flow CMR was successfully acquired with diagnostic image quality in 99% of cases, cine volumes were of diagnostic quality in all but 10 cases (87% success rate) due to early awakening. T2 SPACE sequence for lymphatic assessment was diagnostic in 12 cases (80%), with 3 awakenings. All awakenings occurred within the first 31 scans, with no further awakenings recorded afterward.

Conclusion:

Rapid protocol for neonatal feed-and-wrap CMR in CHD is well tolerated with a feasible mean scan time of 25min. Standard assessments require 30min scan slots and complex CHD 45min. The reduced frequency of awakenings and extra sequences suggest a learning curve for scan time and protocol. This rapid, free-breathing, non-contrast, sedation-free approach aids therapeutic decisions in neonates and improves the environmental sustainability of CMR.