Silverlight animation heart beat pulse

Can someone point me into the right direction. Basically I want to create heart beat pulse animation in silverlight.
The control can be a rectangle or a button.


I have a window service running in the background. So when I have a heartbeat functions thats being call every 10minutes so to keep the windows service live. So for every time the heartbeat function is executed. I want to show the cool control  pulse animation.

Can someone assist me?