I'm sorry he had a panic attack but thankful it wasn't a heart attack. The same thing happened to my aunt a few months ago. I did some quick research for you and this is what I came up with:
Panic attacks are periods of intense fear or apprehension that are of sudden onset and of variable duration from minutes to hours. Panic attacks usually begin abruptly, may reach a peak within 10 minutes, but may continue for much longer if the sufferer had the attack triggered by a situation from which they are not able to escape. In panic attacks that continue unabated, and are triggered by a situation from which the sufferer desires to escape, some sufferers may make frantic efforts to escape, which may be violent if others attempt to contain the sufferer. Some panic attacks can subside on their own over the next several hours. http://en.wikipedia.org/wiki/Panic_attack
The main treatment options for panic attacks are psychotherapy and medications. Both are effective. Your doctor likely will recommend one or both types of treatment, depending on your preference, your history, the severity of your panic disorder and whether there are therapists with special training in panic disorders in your area. http://www.mayoclinic.com/health/panic-attacks/DS00338/DSECTION=treatments-and-drugs
Hope this helps!