Davis M. Vigneault BS, Presenter: Nothing to Disclose

Eunice Yang MD, Abstract Co-Author: Nothing to Disclose

Linda Chi Hang Chu MD, Abstract Co-Author: Nothing to Disclose

Carolyn Ho, Abstract Co-Author: Nothing to Disclose

David A. Bluemke MD, PhD, Abstract Co-Author: Research support, Siemens AG

Circumferential strain (εcc) increases from epicardium to endocardium in normal patients. However, evaluation of strain at the myocardial surfaces is difficult with tagged CMR, which is better suited to midwall strain analysis. CMR feature tracking is a novel technique which directly tracks motion at the myocardial borders. The purpose of this study was to test the feasibility of using feature tracking to evaluate circumferential transmural strain gradient (cTSG, the difference endocardial and epicardial εcc) in patients with hypertrophic cardiomyopathy (HCM).

Subjects with a clinical diagnosis of overt HCM and their family members were invited to participate in this multi-center, prospective, cross-sectional study. Genetic testing was performed, and left ventricular hypertrophy (LVH) was assessed by echocardiography or CMR. Patients were categorized as control (mutation–/LVH–, n=30), preclinical (mutation+/LVH–, n=37), or overt (mutation+/LVH+, n=48) HCM. Mid ventricular short axis cine images were analyzed at using Multimodality Tissue Tracking software (MTT Version 6.0.4725, Toshiba Medical Systems Corporation, Tokyo, Japan).

Global endocardial εcc was significantly increased in overt patients (-29.8% ± 6.6%) relative to preclinical (-26.6% ± 4.8%, p = -0.011) and control (-24.6% ± 4.3%, p < 0.0001). Global epicardial εcc showed a decreasing trend from control to preclinical to overt. cTSG increased significantly from control (-13.7% ± 3.6%) to preclinical (-17.0% ± 4.0%) to overt (-19.2% ± 7.8%), (p < 0.01). Significant differences were observed between preclinical and control in the septum (p < 0.01), overt and preclinical anteriorly (p < 0.001), and overt and control in all segments (p < 0.0001).

CMR feature tracking is feasible in HCM, and detected an increased strain gradient between the endocardial and epicardial surfaces.

Patients with gene positive HCM but without wall thickening (LVH-) may have subtle abnormalities in myocardial strain in early disease detected by CMR feature tracking, relative to control and overt HCM patients.

Vigneault, D, Yang, E, Chu, L, Ho, C, Bluemke, D, Left Ventricular Strain Gradient Is Abnormal in Hypertrophic Cardiomyopathy: Assessment by CMR Feature Tracking.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014211.html