In order to provide income over the lifetime of the retiree, the TDF is designed to increasingly invest in deferred annuities as the TDF reaches its target retirement date and investors in the TDF get older.
Freebase(0.00 / 0 votes)Rate this definition: Echocardiography. Echocardiogram, often referred to cardiac echo or simply an echo is a sonogram of the heart. Echocardiography uses standard two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart.
Echocardiogram - Echo. 1  The size and shape of your heart, and the size, thickness and movement of your heartâs walls. 2  How your heart moves. 3  The heartâs pumping strength. 4  If the heart valves are working correctly. 5  If blood is leaking backwards through your heart valves (regurgitation). 6  If the heart valves are too narrow (stenosis).