minimally invasive direct coronary artery bypass surgery minimally invasive direct coronary artery bypass surgery minimally invasive direct coronary artery bypass (midcab) is a surgical treatment for coronary heart disease that is a less invasive method of coronary artery bypass surgery (cabg). midcab gains surgical access to the heart with a smaller incision than other types of cabg. midcab is sometimes referred to as "keyhole" heart surgery because the operation is analogous to operating through a keyhole. minimally invasive direct coronary artery bypass surgeryicd-9-cm36.33 midcab is a form of off-pump coronary artery bypass surgery (opcab), performed "off-pump" – without the use of cardiopulmonary bypass (the heart-lung machine). midcab differs from opcab in the type of incision used for the surgery; with traditional cabg and opcab a median sternotomy (dividing the breastbone) provides access to the heart; with midcab, the surgeon enters the chest cavity through a mini-thoracotomy (a 2-to-3 inch incision between the ribs). midcab surgery is no longer reserved for only anteriorly placed single- or double-vessel diseases, because such lesions are usually managed with angioplasty. the surgery has recently begun to be used in multi-vessel coronary disease. midcab in hybrid revascularization people with multi-vessel coronary disease, who desire a minimally invasive approach to surgery may be eligible for hybrid bypass. a hybrid approach combines coronary bypass (using the midcab approach) and coronary stenting.