Comparison of tissue tracking assessment by cardiovascular magnetic resonance for cardiac amyloidosis and hypertrophic cardiomyopathy

Background: Administration of gadolinium-contrast can cause problems in cardiac amyloidosis (CA) patients with impaired renal function.

Purpose: To compare patterns of cardiovascular magnetic resonance tissue tracking (CMR-TT) for CA and hypertrophic cardiomyopathy (HCM) and to assess the feasibility of CMR-TT to distinguish between these diseases without administration of gadolinium-contrast.

Material and methods: Included were 54 patients with biopsy-proven CA, 40 patients with HCM, and 30 healthy people. We calculated strain ratio of apex to base (SRAB) in the left ventricle (LV) using radial (R), circumferential (C), and longitudinal (L) strain from CMR-TT. The LV ejection fraction (LVEF) and the ratio of septal to posterior wall at basal level were also calculated. Late gadolinium enhancement (LGE) image analysis was performed for differential diagnosis. Area under the receiver operating characteristic curve (AUC) comparisons were used.

Results: All SRAB values were significantly different between CA and HCM (all P < 0.001). AUC values for parameters were 0.806 for LVEF, 0.815 for ratio of wall thickness, 0.944 for the LGE pattern, 0.898 for SRAB_R, 0.880 for SRAB_C, and 0.805 for SRAB_L. AUCs for the LGE pattern were significantly higher than for LVEF, ratio of wall thickness and SRAB_L (all P < 0.008). No significant differences were seen between AUCs for the LGE pattern, SRAB_R, and SRAB_C (all P > 0.109).

Conclusion: SRAB_R and SRAB_C were reliable parameters for distinguishing between CA and HCM.