Evaluation of pulsed Doppler tissue velocity imaging for assessing systolic function of murine global heart failure

The feasibility of Doppler tissue imaging (DTI) for assessing global systolic function has not been determined in small animals, particularly at near-conscious heart rates. Therefore, we compared DTI measurements with conventional M-mode-derived fractional shortening in murine global left ventricular systolic dysfunction induced by intraperitoneal doxorubicin (Dox) injection. In all, 13 female C57BL mice received 20 mg/kg of Dox and 12 mice received saline injection (controls). DTI signals were obtained from the inferior wall through parasternal short-axis views. The heart rate was kept at near-conscious level throughout DTI measurements (approximately 500/min). Left ventricular systolic dysfunction was detectable by measurements of fractional shortening from 4 to 14 days after Dox administration. Among DTI measurements, peak systolic velocity and time to peak systolic velocity decreased from 4 to 14 days after Dox injection. Our results indicate that these new DTI measurements appear feasible to assess global left ventricular systolic dysfunction in mice.