Fig. 9.

QTc prolongation, cardiac ischemic events, and fatal arrhythmias are evident in antemortem EKG tracings of sickle mice. Compared with the normal sinus rhythm in a 2-mo-old WT control (1), antemortem EKG tracings of an age-matched Berk-SS mouse shows ST depression (2). Another 2-mo-old Berk-SS mouse’s antemortem EKG tracings show slower heart rate and P-wave irregularity (3), which progressed into outright atrial flutter with 4–5:1 AV conduction (4), and eventual ventricular fibrillation (5). Sudden and significant QTc prolongation of three 6-wk-old Berk-SS male mice few days before their death (filled triangle) compared with their age- and gender-matched WT (open triangles) controls (6). Data shown as mean ± SEM n = 8 mice in WT and 3 mice in Berk-SS; Mann-Whitney U test; ns, P > 0.05; *P ≤ 0.05.