Although patients who will undergo coronary artery bypass surgery are given beta blockers a day before their operation, a new study suggests that the standard medical practice may not really improve the outcome of the surgery at all. Beta blockers are prescribed to reduce blood pressure, control abnormal heart rhythms and treat a number of health conditions including heart attack, migraine and glaucoma.
Researchers of a new study focused on the use of beta blockers in coronary artery bypass grafting (CABG) surgery, which is done to improve blood flow to the heart, said that the use of beta blockers a day before the bypass surgery does not just provide no significant benefit, it could even cause slightly increases rates of atrial fibrillation, a heart condition that is characterized by irregular and rapid heart rate that could restrict blood flow and oxygen supply to the body.
For the study published in the JAMA Internal Medicine on June 16, William Brinkman, from the Cardiopulmonary Research Science and Technology Institute in Dallas, Texas, and colleagues reviewed the records of more than 506,000 individuals who had non-emergency CABG between 2008 and 2012, did not have a heart attack within 21 days prior to the operation and had no high-risk symptoms to determine if the use of beta blockers 24 hours before bypass surgery has an impact on the incidence of post-surgery death, stroke, reoperation, renal failure, prolonged ventilation, deep sternal wound infection and atrial fibrillation.
The researchers found that there were no difference in the rate of deaths as well as in the incidence of stroke, kidney failure or infection between 86 percent of the participants who were prescribed with beta blockers a day before their surgery and the rest of the participants who were not given the medication. The researchers have likewise observed that patients who received beta blockers had increased rates of atrial fibrillation compared to patients who did not have beta blockers.
"Preoperative β-blocker use among patients undergoing non-emergent CABG surgery who have not had a recent myocardial infarction was not associated with improved perioperative outcomes," the researchers wrote.
David Shahian, from Massachusetts General Hospital in Boston, said that although the findings of the study are interesting, the results are at odds with majority of the studies on the subject. He urged doctors to continue following medical guidelines and giving beta blockers to patients before bypass surgery.
"This study was not able to take into account the specific beta blocker, the dose, and how long before surgery it was started," Shahian said. "These are important factors that may affect the results of this study."