pff-pump versus on-pump coronary artery bypass:does number of grafts performed rappresent a selection bias in comparative studies?

BACKGROUND: Several retrospective studies comparing off-pump and on-pump coronary surgery and the largest randomized studies published to date showed a lower number of grafts performed in patients submitted to off-pump coronary artery bypass surgery (OPCAB). These findings bring about the question of the general applicability of the results. We eliminated the selection bias correlated with the number of grafts per patient by comparing the short-term outcomes of patients undergoing OPCAB and standard coronary artery bypass grafting (CABG) matched for number of grafts. METHODS: Eighty-seven consecutive patients undergoing OPCAB (group A) were selected from the database of our Institution duri…