Cardiac function in vivo
obesity, stroke, LV dP/dt
OBESITY, DIASTOLIC DYSFUNCTION, OBESE, OBESE, STROKE
Echocardiography at baseline (21 weeks of age) revealed that both groups of obese ZSF1 rats showed signs of volume expansion when compared to lean ZSF1 rats, manifest from larger left atrial area (LAA) and LV end‐diastolic volume (LVEDV, Table Echocardiography and left ventricular hemodynamics of lean and obese ZSF1 rats at 21‐ and 25 weeks of age.
Abbreviations: CO, cardiac output; DT, deceleration time; E/A, ratio of the early (E) wave and late (A) wave during diastolic filing; EDPVR, end‐diastolic pressure volume relationship.; EDV, end‐diastolic volume; EF, ejection fraction; ESV, end systolic volume; FS, fractional shortening; IVRT, isovolumic relaxation time; LAA, left atrial area; LV, left ventricle; LVEDP, left ventricular end‐diastolic pressure; LVIDd, left ventricular internal diameter end diastole; LVIDs, left ventricular internal diameter end systole; LVPSP, left ventricular peak systolic pressure; SV, stroke volume.The bolded values indicate that are statistically significantly different.At the 25‐week time point, vehicle‐treated obese ZSF1 rats exhibited an average ~ 30% increase in the isovolumetric relaxation time (IVRT; Table Oral GGA treatment halts the progression of diastolic dysfunction, measured as isovolumic relaxation time. Upper panel: Representative scans of transmitral pulse wave Doppler in Lean, Obese, and Obese rats treated with GGA as acquired from the apical long‐axis view at 25 weeks. Green cross‐hair cursors indicate the position used to calculate the IVRT. Lower panel: absolute IVRT values in 21‐ and 25‐week‐old lean and obese rats, measured by transthoracic echocardiography (see Methods). Effects of obesity and oral GGA treatment on progression of diastolic dysfunction, measured as the enhancement of IVRT from 21 to 25 weeks (ΔIVRT). Data are expressed as mean ± SEM. Invasive LV pressure‐volumetry assessment did not show overt diastolic impairment in obese ZSF1 rats as shown by LV end‐diastolic pressure (LVEDP), LV dP/dt