The value of left ventricular T1 mapping and left atrial strain for distinguishing myocardial amyloidosis and hypertrophic cardiomyopathy.

Purpose: This study aimed to use T1 mapping and left atrial feature tracking techniques to distinguish myocardial amyloidosis (CA) from hypertrophic cardiomyopathy (HCM).

Methods: A retrospective analysis was conducted on 130 subjects who underwent cardiac magnetic resonance examinations from January 2021 to May 2024 at 1.5 and 3.0 T systems. Measurements of global left ventricular myocardial T1 values were performed, a standardized T1 z-score used as an assessment metric to overcome the effects of various manufacturers and field strengths. Left atrial strain was measured with feature tracking techniques.

Results: 42 CA patients、58 HCM patients and 30 healthy subjects were analyzed. For both 1.5T and 3.0T systems, the overall T1 values of LV myocardium was significantly higher in the CA group compared with the HCM and control groups (p < 0.001). T1z-scores in the CA and HCM groups were 4.8 ± 2.2 and 3.4 ± 1.9, respectively (p < 0.001). Myocardial strain analysis showed that atrial strain was significantly lower in the CA group when compared with the HCM and healthy control groups (p < 0.05). The correlation between left atrial strain and function parameters was assessed through Spearman correlation analysis. Multivariate logistic regression analysis showed that a combination model including T1z-score and left atrial reservoir function (Es) had an improved ability to discriminate CA and HCM with a higher AUC (0.937), with a sensitivity of 95.2% and a specificity of 83.3% (P < 0.05).

Conclusion: T1 mapping combined with Εs could effectively distinguish CA from HCM, and provide new insights for the diagnosis of the etiology and treatment of cardiac hypertrophic diseases.