Off-pump CABG Can Lower Hospital Mortality Rate

Coronary artery bypass grafting (CABG) without cardiopulmonary bypass achieves lower hospital mortality rates than the conventional method that employs bypass, according to study findings presented January 30 at the 37th annual meeting of The Society of Thoracic Surgeons.

Dr. Paul J. Corso, from Washington Hospital Center, in Washington, DC, and colleagues retrospectively compared the in-hospital mortality of 852 patients who underwent off-pump CABG with the in-hospital mortality of 4260 patients who underwent conventional, on-pump CABG. Patients were matched for age, number of vessels grafted, left ventricular dysfunction, gender, and reoperative status.

Compared with off-pump CABG patients, the researchers found that on-pump patients had 2.8 times the risk of experiencing an in-hospital death. In addition, patients with chronic obstructive pulmonary disease, CCS class III/IV disease, diabetes, peripheral vascular disease, a history of cerebrovascular accident, and those who had received preoperative inotropes also had a significantly increased risk of in-hospital death.

“We have actually followed these off-pump patients out for 10 years now and their morbidity and mortality is quite excellent in terms of event-free survival, acute infarct rate, and need for target vessel revascularization,” Dr. Corso told Reuters Health. “This is another piece of evidence showing that we are not compromising quality in the long-term, and that we should continue to pursue and develop beating heart surgery.”

“In the old days, when off-pump surgery was done, it was technically demanding for the surgeon. But it was developed to a point where it became not so technically demanding,” Dr. Corso said.

“By taking away the pump, we’ve made the procedure surgeon- and anesthesiologist-dependent again,” he explained. “I think as surgeons become more comfortable with the procedure then a greater percentage will be done.”

In the “last 6 months, 70% of our CABGs have been off-pump,” Dr. Corso noted. “Across the country, probably only about 20% of cases are done off-pump.”

Dr. Corso is “convinced that these patients do have a lower morbidity and mortality,” and believes that techniques need to be developed to allow more patients to undergo CABG without the heart-lung machine. He estimates that “70% of the risk of cardiac surgery is related to the use of the pump.”