The use of PPI for GI protection in patients treated with dual anti-platelet therapy is not based on randomized trials, but rather on expert opinion. Since H2 blockers are also effective in preventing acid secretion and are not known to interact with the P450 system that affects clopidogrel, the investigators hypothesized that these group of drugs will not interfere with the positive antiplatelet effects of clopidogrel and therefore will offer a good alternative treatment option.