Tissue Characterization

1355693 - Early Experience with Cardiac Sodium-23 Images in Ultra-High Field 7T MRI

Wednesday, January 25, 2023

5:00 PM – 6:30 PM

Location: Silver Pearl 1

Presenting Author(s)

Carlos Eduardo E. Rochitte, MD, PhD

Associate professor of Cardiology
Heart Institute, University of São Paulo
Sao Paulo, Sao Paulo, Brazil

Background:

The use of sodium-23 (²³Na) as a biomarker nucleus is limited in 1.5 and 3 Tesla scanners available for clinical use due to low concentration and gyromagnetic characteristics4; 7. In recent years, with the advent of ultra-high field 7 Tesla scanners, these limitations could be mitigated and can further expand the potential in the evaluation of the heart 2; 4; 7; 8. Ultra-high field (UHF) 7 Tesla has the potential to enable the assessment of²³Na for heart on human CMR. ²³Na had good relationship with cardiac ischemic areas, as shown in prior animal studies.

Purpose: The aim of this study was to evaluate the clinical potential of the assessment of ²³Na image on human heart in UHF 7T CMR scanner.

Methods:

Four volunteers (table1.) were evaluated with 7T CMR (Magneton 7T Siemens Healtineers – GhMb) using the ⁺H and ²³Na generate cardiac images. The ⁺H images were evaluated by experts cardiologists and classified as damaged (IQ-1), acceptable (IQ-2), appropriate (IQ-3), and excellent (IQ-4) and the ²³Na, in addition, were evaluated according to anatomic agreeement between ⁺H/²³Na images and the measurement of signal and noise ratio (SNR) on left ventricle (LV) and septum interventricular (SIV). Pulse sequences for sodium-23 was an ultrashort-TE gradient-echo and for hydrogen-1 a FLASH sequence, with parameters shown in table 2.

Results:

For all volunteers (V) it was possible to reach clinical image quality with ⁺H (V1- IQ-2; V2 - IQ-3; V3 IQ-3; V4 - IQ-4). All ²³Na images had good anatomical agreement with ⁺H cine images with acceptable SNR for both LV cavity and interventricular septum, with higher SNR in the blood due to ²³Na higher concentration. Figures 1 and 2 are example of the imaging quality obtained in this pilot

Conclusion:

Cardiac sodium-23 imaging at UHF 7T CMR scanner allows for the evaluation of the myocardium with acceptable image quality and signal-to-noise ratio close to the hydrogen-1 images. Our results indicate that ²³Na imaging at UHF 7T systems can assess sodium human myocardium concentration, and might be able to detect sodium changes in abnormal myocardium.