Echocardiographic characterization of left ventricular adaptation in a genetically determined heart failure rat model

This study uses echocardiography to characterize the pattern of left ventricular hypertrophy in a new hypertensive heart failure-prone rat strain designated SHHF/Mcc-cp (SHHF). M-mode echocardiograms of the left ventricle in nine 10- to 12-month old SHHF rats and nine age-matched spontaneously hypertensive rats (SHR) were compared. Wistar-Kyoto and Sprague-Dawley strains served as the normotensive control group. SHHF rats had significantly greater left ventricular mass than did rats in the normotensive control group. Although left ventricular mass was not different between SHHF and SHR, significant differences were seen in the pattern of left ventricular remodeling as determined by relative wall thickness. These differences in left ventricular remodeling may explain the earlier development of heart failure in SHHF. The different patterns of left ventricular hypertrophy in SHHF and SHR suggests that heart failure in SHHF is not mediated by hypertension alone.