what is the best approach in patients treated with aspirin or clopigogrel or anticoagulants before gastroenterologic procedures

the withdrawal of antiplatelet agents is probably not as safe as we think previously. 

The recommendation is that if patients are on aspirin, keep them on aspirin if they need it for secondary prophylaxis. If theyre taking it for primary prophylaxis, you could consider stopping it. except active bleeding, dont stop aspirin. 

Stent thrombosis can occur in approximately 30% of those patients within a month of stopping the clopidogrel. For a bare metal stent, the recommendation is that patient has tocontinue the clopidogrel for 30 days. Patientsshould continue on aspirin.

For drug-eluting stents, patient should continue clopidogrel for 6 months and probably a lot longer than that.