Ageing has important deleterious effects on the cardiovascular system. We sought to compare intra-ventricular kinetic energy (KE) in healthy subjects of varying ages to subjects with ventricular dysfunction to understand if changes in energetic momentum may predispose individuals to heart failure. 4D flow MRI was acquired in 35 healthy subjects (aged 1-67 years) and 10 patients with dilated cardiomyopathy (DCM) (aged 28-79years). Healthy subjects were divided into age quartiles (1st quartile <16 years, 2nd quartile 17-32 years, 3rd quartile 33-48 years, 4th quartile 49-64 years). KE was measured in the left ventricle throughout the cardiac cycle and indexed to ventricular volume. In healthy subjects two large peaks corresponding to systole and early diastole occurred during the cardiac cycle. A third smaller peak was seen during late diastole in eight adults. Systolic KE (p = 0.182) and ejection fraction (EF) (p =0.921) were preserved through all age groups. Older adults showed a lower early peak diastolic KE compared to children (p < 0.0001) and young adults (p =0.025). Subjects with DCM had reduced EF (p <0.001) and when compared to older healthy adults exhibited a similar early peak diastolic KE (p =0.142) but with the addition of an elevated KE in diastasis (p =0.029). In healthy individuals, peak diastolic KE progressively decreases with age whilst systolic peaks remain constant. Peak diastolic KE in the oldest subjects is comparable to those with LV dysfunction. Unique age related changes in ventricular diastolic energetics might be physiological or herald sub-clinical pathology.
- four dimensional flow MRI
- cardiac MRI
- cardiac function
- heart failure
- Copyright © 2015, American Journal of Physiology - Heart and Circulatory Physiology