Rapid Fire Abstracts
Michael C. Yim, MD
Chief Medical Resident
Cleveland Clinic
Michael C. Yim, MD
Chief Medical Resident
Cleveland Clinic
Makiya Nakashima, MSc
Research Data Scientist II
Cleveland Clinic
Theerawat Korkerdsup, MD
Advance imaging cardiologist
Bangpakok 9 International Hospital , Thailand
Jesse I. Hamilton, PhD
Assistant Professor
University of Michigan
Nicole Seiberlich, PhD
Professor
University of Michigan
Wilson Tang, MD
Cardiologist
Cleveland Clinic
David Chen, PhD
Director of Artificial Intelligence
Cleveland Clinic
Danielle Kara, PhD
Staff Scientist
Cleveland Clinic
Christopher Nguyen, PhD, FSCMR, FACC
Director, Cardiovascular Innovation Research Center
Cleveland Clinic
Deborah Kwon, MD, FSCMR
Director of Cardiac MRI
Cleveland Clinic
Brendan Eck, PhD
Scientist
Cleveland Clinic
Myocardial T1 and T2 mapping enables quantitative evaluation of myocardial tissue abnormalities such as infiltrative disease and edema/inflammation.1 Cardiac Magnetic Resonance Fingerprinting (cMRF) simultaneously generates T1 and T2 maps in a single scan, allowing increased efficiency and inherent spatial co-registration of tissues between the maps.2 Whereas cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) both exhibit pathological cardiac enlargement, it has been shown that conventional T1 maps can distinguish CA from HCM patients.3 Recently, cMRF T1 and T2 mapping was reported to discriminate CA compared from control subjects.4 However, direct comparison of cMRF-derived T1 and T2 between HCM and CA patients has not been studied. This study aims to compare myocardial cMRF T1 and T2 values between HCM and CA patients.
Methods:
Five HCM patients and 14 CA patients were prospectively scanned at a 3T Prisma Siemens Scanner under an institutional review board approved protocol in a gated cMRF and conventional acquisition. Conventional T1 and T2 maps were obtained with Modified Look-Locker Inversion and T2-prepared balanced Steady State Free Precession respectively, and cMRF maps were obtained using a breath-held, 15-heartbeat, ECG/pulse-gated sequence. Reconstruction of cMRF images was performed offline and included scan-specific dictionaries and local low rank reconstruction.5 Apex, mid, and base left ventricular (LV) cardiac short axis slices were acquired. Manually contoured myocardium T1 and T2 average values for each slice were compared between HCM and CA, and multivariate analysis of variance (MANOVA) was performed to assess differences in conventional and cMRF T1 and T2 values between the groups at the apex, mid, and base slices.
Results:
A total of 220 slices were analyzed (55 for conventional T1, 55 for conventional T2, 55 for cMRF T1, and 55 for cMRF T2). An example of T1 and T2 maps derived using cMRF in an HCM patient is shown in Figure 1a and 1b; corresponding maps in a CA patient are shown in Figure 1c and 1d. cMRF T2 and Conventional T1 and T2 values were not significantly higher in CA patients compared to HCM patients, (p = 0.428, 0.063, 0.219), while myocardial T1 measured using cMRF were significantly elevated in CA patients compared to HCM patients (p = 0.015). Average T1 and T2 values measured in different cardiac slices are shown in table 1. Myocardial T1 and T2 values are shown in Figure 2.
Conclusion:
T1 maps generated using cMRF demonstrated improved distinction between CA patients and HCM patients compared to conventional approaches. While conventional T1 values were elevated in CA patients compared to HCM patients, this increase did not reach statistical significance in our study, potentially due to the small sample size and high variance in average apex slice T1 values in our study population. In contrast, cMRF T1 more effectively captured the distinct myocardial characteristics of these two conditions. Given the ability to generate anatomically co-registered T1 and T2 maps simultaneously in a single, efficient scan, cMRF can potentially be a valuable tool in assessing patients with LV hypertrophy for the presence of infiltrative disease.
