Background: Left ventricular (LV) wall stiffening plays an important role in the development of heart failure with preserved ejection fraction (HFpEF). Based on the linear elastic theory, we hypothesized that the evaluation of epicardial movement during diastole is helpful for the noninvasive assessment of LV wall distensibility.
Methods and results: Based on the linear elastic theory, the epicardial movement index (EMI) was calculated on the echocardiogram as: [see text.] We calculated diastolic wall strain (DWS) as follows to examine whether DWS substitutes for EMI: [see text.] The animal study using hypertensive Dahl salt-sensitive rats, HFpEF model, and normotensive Dahl rats showed the significant and inverse correlation of EMI or DWS with myocardial stiffness constant. Preload alteration did not affect EMI or DWS. In the clinical study, the HFpEF patients had lower EMI and DWS than the normal volunteers and the asymptomatic patients with LV hypertrophy.
Conclusions: The evaluation of epicardial movement may be useful in noninvasively assessing wall distensibility in the absence of LV systolic dysfunction.