Impact of ferumoxytol vs gadolinium on 4D flow cardiovascular magnetic resonance measurements in small children with congenital heart disease

Abstract

Background Cardiovascular magnetic resonance (CMR) allows for time-resolved three-dimensional phase-contrast (4D Flow) analysis of congenital heart disease (CHD). Higher spatial resolution in small infants requires thinner slices, which can degrade the signal. Particularly in infants, the choice of contrast agent (ferumoxytol vs. gadolinium) may influence 4D Flow CMR accuracy. Thus, we investigated the accuracy of 4D Flow CMR measurements compared to gold standard 2D flow phase contrast (PC) measurements in ferumoxytol vs. gadolinium-enhanced CMR of small CHD patients with shunt lesions. Methods This was a retrospective study consisting of CMR studies from complex CHD patients less than 20 kg who had ferumoxytol or gadolinium-enhanced 4D Flow and standard two-dimensional phase contrast (2D-PC) flow collected. 4D Flow clinical software (Arterys) was used to measure flow in great vessels, systemic veins, and pulmonary veins. 4D Flow accuracy was defined as percent difference or correlation against conventional measurements (2D-PC) from the same vessels. Subgroup analysis was performed on two-ventricular vs single-ventricular CHD, arterial vs venous flow, as well as low flows (defined as < 1.5 L/min) in 1V CHD. Results Twenty-one ferumoxytol-enhanced and 23 gadolinium-enhanced CMR studies were included, with no difference in age (2.1 ± 1.6 vs. 2.3 ± 1.9 years, p = 0.70), patient body surface area (0.50 ± 0.2 vs. 0.52 ± 0.2 m2, p = 0.67), or vessel diameter (11.4 ± 5.2 vs. 12.4 ± 5.6 mm, p = 0.22). Ten CMR studies with single ventricular CHD were included. Overall, ferumoxytol-enhanced 4D flow CMR measurements demonstrated less percent difference to 2D-PC when compared to gadolinium-enhanced 4D Flow CMR studies. In subgroup analyses of arterial vs. venous flows (high velocity vs. low velocity) and low flow in single ventricle CHD, ferumoxytol-enhanced 4D Flow CMR measurements had stronger correlation to 2D-PC CMR. The contrast-to-noise ratio (CNR) in ferumoxytol-enhanced studies was higher than the CNR in gadolinium-enhanced studies. Conclusions Ferumoxytol-enhanced 4D Flow CMR has improved accuracy when compared to gadolinium 4D Flow CMR, particularly for infants with small vessels in CHD.

Unveiling the next generation of MRI contrast agents: current insights and perspectives on ferumoxytol-enhanced MRI

“…Another use-case of FE-MRA worth noting in refining clinical CMR routines is ferumoxytol-enhanced 4D flow MRI, which integrates functional assessment with anatomical visualization. Compared to GBCAs, ferumoxytol-enhanced 4D flow MRI provides higher accuracy in measuring the flow, superior image contrast and effective ventricular mass evaluation [ 62 ]. Owing to its extended duration within the bloodstream, ferumoxytol-enhanced CMR lessens the need for patients to undergo anesthesia and withhold breathing [ 63 ].…”

The Functioning of the Frog’s Single Ventricle

“…• Amphibians such as the Xenopus Laevis have a single ventricle, both in terms of morphology and function, whereas children with functionally single ventricle typically have two ventricles albeit in a setting of one ventricle being severely hypoplastic • Our observations with flows measurements performed using echocardiography constitute another initial step towards a complete analysis of the function of the frog's single ventricle [62] • because of logistic reasons the echocardiographic measurements were performed at a room temperature of 22 • C, higher than the 17 • C, normal environmental temperature for frogs • Studies of the systemic and pulmonary flows distribution with the more modern methodologies of ECG-gated MRI, validated in small vessels in experimental as well as clinical studies could provide high quality of innovation and creativity for our translational research [63][64][65][66][67][68][69][70][71][72][73][74][75][76][77] • We always have to be aware of the species-to-species differences…”