Abstract 18015: “Apical Sparing” Longitudinal Strain Pattern With Cardiac MRI Correlates With LGE Distribution in Cardiac Amyloidosis
Introduction: Regional variations in longitudinal strain (LS) have been demonstrated on echocardiography in patients with cardiac amyloidosis (CA).
Hypothesis: We aimed to describe regional patterns in LS using feature-tracking software applied to cardiac MRI images (CMR) in CA, hypertrophic cardiomyopathy (HCM), and Anderson-Fabry’s disease (AFD) and to relate these patterns to late gadolinium enhancement (LGE).
Methods: Patients with CA (n=51) were compared to left ventricular mass index balanced patients with HCM (n=20) and AFD (n=20). LS analysis was performed using Velocity Vector Imaging (VVI) on steady state free precession cine images (4, 3, and 2-chamber views). Values were recorded for each of 18 myocardial segments. A regional LS ratio representing “apical sparing” was calculated as the ratio of the sum of the apical segmental LS values divided by the sum of the basal and mid-segmental LS values. LGE was quantified for the basal, mid, and apical myocardial segments using a threshold of 5SD above remote myocardium. A regional LGE ratio was calculated similar to the “apical sparing” ratio.
Results: The regional LS ratio was significantly higher in patients with CA (1.05±0.49) than in patients with AFD (0.79±0.24; p=0.025) and HCM (0.84±0.32; p=0.025). In patients with CA there was a regional difference in LGE burden, with lower LGE in the apex (31.9±20%) compared to the basal (52.7±22%) and mid-segments (37.9±19%). The regional LGE ratio was significantly lower in patients with CA (0.34±0.14) than in patients with AFD (0.54±0.64; p<0.001) and HCM (0.73±0.41; p<0.001).
Conclusions: Cardiac amyloidosis is characterized by regional variations in LS from base to apex. “Apical sparing” in LS is seen with CMR images and can be an additional tool to differentiate CA from other causes of LVH. The concomitant presence of a base to apex gradient in LGE burden by CMR suggests that the regional strain gradient may be associated with burden of amyloid deposition.
- Cardiac amyloidosis
- Left ventricular hypertrophy
- Cardiac Magnetic Resonance Imaging
- Myocardial Mechanics
- Late Gadolinium Enhancement
Author Disclosures: L.K. Williams: None. J. Forero: None. A. Calleja: None. D. Delgado: None. A.M. Crean: None. H. Rakowski: None. P. Thavendiranathan: None.
- © 2015 by American Heart Association, Inc.