MODULE SUPPLEMENT: CARDIOVASCULAR SYSTEM
Pulse Wave Velocity

What about pulse wave velocity?

During each heart beat a pulse wave travels from the heart down the arterial wall in advance of blood flow (Lakatta, 1999). The more rigid the wall of the artery, the faster the wave moves. When the wave hits the major branching points, such as at the renal and femoral arteries, these waves are reflected back so that they reverse direction and travel back to their point of origin.

Normally, the reflected wave gets back to the starting point after the aortic valve is closed. This amplifies diastolic pressure and facilitates blood flow to the coronary arteries. However, the increased wave velocity of the initial wave and the subsequent reflected wave that occurs with age means the wave can get back to the point of origin BEFORE the aortic valve closes which increases SYSTOLIC rather than diastolic pressure. It also decreases the contribution of the reflected wave to the filling of the coronary arteries. These changes can have significant clinical implications in terms of coronary artery blood flow and can contribute to an increase in systolic blood pressure.