Fig. 2.

Sickle mice exhibit progressive LAE compared with their age- and gender-matched WT controls, which is unique to SCA and does not develop in the IDA mice. (A) Representative images of parasternal long-axis M-mode imaging through the aortic root and LA demonstrating cross-sectional atrial dilation in a 1- and 8-mo-old sickle cell and WT mouse. The smaller upper image in each set shows the 2D picture of this region of the heart in the parasternal long axis, and the lower image records the movement of each pixel during the cardiac cycle, allowing quantification of structure sizes. Under normal conditions, the LA and aortic root are of approximately equal size. The subpanels are: (a) 1-mo-old WT control mouse; (b) 8-mo-old WT control mouse; (c) 1-mo-old sickle cell mouse (Berk-SS); (d) 8-mo-old Berk-SS. Ao, aortic root; LA, left atrium. (B) A temporal analysis of LAD by M-mode imaging of WT and Berk-SS mice starting soon after weaning to 8 mo of age. (C) Assessment of LAD by transthoracic echocardiography in experimentally induced IDA to achieve hemoglobin levels similar to sickle mice for 3 mo compared with LAD in sickle mice with a similar 3-mo duration of anemia. Data shown as mean ± SEM, n = 4 mice in WT, 6–11 mice in Berk-SS, and 10 mice in IDA; Mann–Whitney U test; ns, P > 0.05; *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001.