The role of three-dimensional speckle tracking imaging in the diagnosis of immunoglobulin light-chain cardiac amyloidosis with normal left ventricular ejection fraction

Objective To explore the value of three-dimensional speckle tracking imaging (3D-STI) in the diagnosis of immunoglobulin light-chain cardiac amyloidosis(AL-CA) patients with normal left ventricular ejection fraction (LVEF). Methods A total of 92 consecutive patients diagnosed with systemic immunoglobulin light chain amyloidosis(sAL) and with normal LVEF from October 2014 to January 2018 in Xijing Hospital were enrolled.Based on the diagnostic criteria of cardiac involvement, the patients were divided into AL-CA group (52 cases) and immunoglobulin light chain amyloidosis (AL) group (40 cases). The clinical data and serological markers of the patients were collected, the conventional echocardiography and full-volume three dimensional dynamic images were acquired, left ventricular global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), and global area strain (GAS) were analyzed using off-line TomTec software. The differences between the two groups were compared. Results Compared with the AL group, the NT-proBNP of AL-CA group was significantly higher (P 0.05). Compared with the AL group, the maximal left ventricular wall thickness, left ventricular mass index, left atrial volume index, and E/e′ in the AL-CA group were significantly increased (all P 0.05). Compared with the AL group, GLS, GAS, and GRS were significantly lower in AL-CA group (all P 0.05). The ROC curve analysis showed that the cut-off values discriminating cardiac involvement were 16.09% for GLS, 36.54% for GAS and 31.90% for GRS. Conclusions 3D-STI measurements of left ventricular myocardial mechanics could detect cardiac involvement in patients with sAL amyloidosis, and provides a new method for diagnosis of AL-CA. Key words: Echocardiography; Three-dimensional speckle tracking imaging; Immunoglobulin light-chain cardiac amyloidosis; Strain