What determines whether a patient will have “on-pump” or “off-pump” coronary artery bypass surgery (CABG)?
—Elissa Internicola Lebow, PA-C, Staten Island, N.Y.
Patients may achieve an excellent outcome with either procedure. Outcomes are likely to depend more on factors other than whether patients underwent standard CABG utilizing the cardiopulmonary bypass machine (on-pump) or if they had the surgery without the use of the machine (off-pump) (also referred to as “beating heart surgery”). Each patient is evaluated independently.
According to results from a meta-analysis conducted by the American Heart Association, patients with atheromatous aorta (severely calcified or diseased aorta), in whom clamping or manipulating the aorta can be associated with dire neurologic consequences, should receive off-pump CABG. The skill, familiarity, and comfort of the surgeon will determine which procedure is performed. A surgeon may not decide the method of the procedure until he has opened the pericardium and seen the coronary arteries. The accessibility of the arteries, such as intra-myocardium, can influence the decision. The patient needs to be able to tolerate the positioning required for off-pump CABG. If manipulating the heart causes ventricular arrhythmias or severe hypotension, traditional on-pump CABG is warranted. Other considerations include renal function and age (older patients tend to have better outcomes with off-pump CABG).
Off-pump CABG requires fewer resources and results in less blood loss, less early neurocognitive dysfunction, less myocardial-enzyme release, and less renal insufficiency. For further discussion, see Circulation. 2005;111:2858-2864.
—Debra Kleinschmidt, PhD, PA (105-16)