Echocardiographic Assessment of BXD Mice

Transthoracic two-dimensional and Doppler echocardiography was used to evaluate heart function and morphology in BXD mice. Experiments were conducted in BXD, B6, and D2 strains (44 strains) at 4–6 months of age (n > 5/strain). The chest of the mice was treated with a chemical hair remover day prior. Mice were anesthetized by oxygenated 1–2% isoflurane, and core temperature and heart rate were maintained using a heated platform set at 37^°C, while echocardiography was performed using a Vevo2100 Micro-Imaging System (VisualSonics Inc., Toronto, Canada). Fractional shortening (FS%), ejection fraction (EF%), left ventricular volumes end-diastolic and end-systolic (LVVol;d and LVVol;s, respectively), LV internal diameters end-diastolic and end-systolic (LVID;d and LVID;s, respectively), interventricular septum end-diastolic and end-systolic (IVS;d and IVS;s, respectively) and LV posterior wall thickness end-diastolic and end-systolic (LVPW;d and LVPW;s, respectively), stroke volume and cardiac output (CO) were calculated as reported previously (19 (link)).