Longitudinal strain of left ventricular basal segments and E/e' ratio differentiate primary cardiac amyloidosis at presentation from hypertensive hypertrophy: an automated function imaging study.

BACKGROUND: Longitudinal strain is an early marker of left ventricular (LV) dysfunction in several cardiac diseases. Our aim was to differentiate cardiac amyloidosis (CA) at diagnosis from hypertensive LV hypertrophy (LVH) by analysis of longitudinal myocardial deformation.

METHODS: Thirty healthy controls (C), 30 newly diagnosed, never treated hypertensives with LVH (H-LVH), and 33 patients with CA at diagnosis underwent echo Doppler including speckle tracking-based automated function imaging (AFI). Averaged peak systolic global longitudinal strain (GLS, 18 segments) and basal, middle, and apical longitudinal strain (BLS, MLS, and ALS, respectively, six segments each) were calculated.

RESULTS: Left ventricular mass index, relative wall thickness, and ejection fraction did not differ between H-LVH and CA. E/e' ratio was higher in CA than in H-LVH (P<.001) and C (P<.0001). GLS was lower in CA than in C (P<.0001), without difference with H-LVH. ALS did not differ among the three groups, MLS was significantly lower in both CA and H-LVH than in C but BLS was lower in CA compared to both H-LVH and C (both P<.0001). In the pooled population, E/e' was independently associated with BLS (β=-0.54, P<.0001). At receiver operating curve analysis, CA was predicted by BLS≤-11.3% (sensitivity=63.3%, specificity=100%) and E/e'≥12.3 (sensitivity=69.7%, specificity=83.3%). The best AUC (=0.819) was obtained by the combination E/e'+BLS.

CONCLUSIONS: Our findings highlight a real difference of E/e' ratio and longitudinal strain of LV basal segments between hypertensive LVH and CA, which could be used to differentiate the two diseases.