Perioperative Aspirin in CABG reduces mortality risk
CABG surgery is performed to restore the normal flow of blood to an obstructed artery in the heart. Cardiac surgery frequently provokes a state of extreme and complex stress with a greatly elevated risk of blood clots and an increased predisposition to long-term vascular disease and mortality. It is hoped that perioperative aspirin may reduce these adverse effects.
Preoperative and postoperative uses of aspirin are defined as within 5 days preceding surgery and continuously on discharge respectively. The discharge prescription of aspirin often is indicated for patients with CABG and it should be continued indefinitely, except for patients with contraindications. The reported rates of patient adherence to the drug for cardiovascular protection are high, range from 72% to 92% in the literature.
Most previous studies on aspirin's effects in cardiac surgery were limited by the length of follow-up. And little is known about perioperative aspirin's effect on the long-term survival in patients undergoing CABG surgery.
For the study, the researchers looked at the medical records of 9,584 patients who received cardiac surgery in three hospitals, selecting the 4,132 individuals who underwent CABG. This selection was then further divided into four groups; in which patients had one of preoperative or postoperative aspirin, both or neither.
Among the studied patients, 76.5% received preoperative aspirin, 23.5% did not 92.3% received postoperative aspirin, and just 7.7% did not. Patients taking preoperative aspirin were significantly more likely to have other risk factors including smoking, diabetes, peripheral vascular disease, angina, high blood pressure, and previous heart attacks.
Professor Sun says: "Our study showed that aspirin was associated with similar effectiveness to other proven medical treatments in patients with cardiovascular diseases, such as statins and ACE inhibitors."
- For patients taking preoperative aspirin, 4-year mortality was 14.8% versus 18.1% for those not taking preoperative aspirin, a statistically significant mortality reduction of 18%.
- For postoperative aspirin, there was a larger mortality reduction: those taking aspirin had a 4-year mortality rate of 10.7%, compared with 16.2% in the non-aspirin patients -- a statistically significant mortality reduction of 34%.
"Among patients undergoing CABG, perioperative uses of aspirin were associated with significant reduction in 30-day mortality and improvement in long-term survival, without significant increased postoperative bleeding complications. We believe that all patients undergoing CABG should take it before and after the procedure, except those for whom aspirin is contraindicated," concluded the authors.