The message of this image is that eating too many burgers from McDonald's is going to make you very sick. Sometimes eating too many burgers will cause you to have a heart attack.
The persuasive technique that is being used is appealing to emotion. This advertisement makes you sorry for the person in the ad who is sick. This inclines you to not eat big macs because you might end up like him.
The ad targets the people who are usually going to fast food restaurants. It suggests to them that when they crave a burger, they should not buy it, but instead eat something healthy.
This ad is not so effective to me because many times I listen to my cravings more than to my real hunger.