TCAD calls lines with arrows on them "leaders". You can find the leader tool in the dimension flyout. You can set them up to have text associated, either plain, in rectangular boxes or bubbles, and with lots of options. All sorts of arrow heads, sizes, and so on.
A typical use for them is to identify components on a drawing, with a number in a bubble that refers to an embedded spreadsheet. You can click on the drawing to place the leader, click where you want the text to go, and tab into a text box. Type your text, and hit alt-F to finish.
Windows 7 ultimate, Core i7 3.07GHz, 4 cores, 9G memory GEForce GTX 285