In patients undergoing heart surgery, concurrent surgical left atrial appendage occlusion (LAAO) is associated with reduced risk of stroke and all-cause mortality, as compared to non-surgical LAAO, according to a study published in The Journal of the American Medical Association.
The study was conducted by Xiaoxi Yao, a health services researcher at Mayo Clinic, and colleagues to evaluate the association of surgical LAAO performed during heart surgery with risk of stroke, mortality, and development of subsequent atrial fibrillation (AF).
The left atrial appendage is often closed by surgeons in people undergoing heart surgery to reduce the risk of stroke in them. LAA is a small sac in the left side of the heart where many blood clots form, during these surgeries. The study conducted by Mayo Clinic researchers confirms that the procedure is likely the right choice for certain patients but not all.
“Our study showed that this intervention is associated with reduced risks of stroke and mortality,” says Xiaoxi Yao. “This is especially true for patients with pre-existing atrial fibrillation, who are at a particularly high risk of stroke.”
For the study, the researchers used OptumLabs Data Warehouse that contains de-identified administrative claims data, including medical claims and eligibility information from a large national U.S. health insurance plan, as well as electronic health record data from a nationwide network of provider groups. Through this, they examined the records of nearly 76,000 adult patients who had a coronary artery bypass or heart valve surgery between Jan. 1, 2009, and March 30, 2017. Of these patients, 5.8 percent (4,374 patients) also had the left atrial appendage closed during the surgery.
These patients were then compared to propensity score-matched patients who did not undergo the surgical closure, evaluating outcomes for 4,295 patients in each group.
- The patients who received the additional procedure were less likely to have a stroke and they were also less likely to die from any cause.
- If the patient had atrial fibrillation before surgery, the numbers were even more positive: lower risks of stroke or death.
- If a patient did not have atrial fibrillation before surgery, those undergoing the surgical closure became somewhat more likely to develop atrial fibrillation within 30 days after the surgery (27.7 versus 20.2 percent).
- In patients with and without pre-existing atrial fibrillation, the surgical closure of the left atrial appendage was associated with a higher rate of health care utilization related to atrial fibrillation, measured over an average of two years of follow-up.
“Atrial fibrillation itself is a risk factor for stroke,” says Peter Noseworthy, M.D., a Mayo Clinic cardiologist and senior author of the study. “So for patients who do not have atrial fibrillation to begin with, the potential benefit of closing the left atrial appendage now could be attenuated by later development of atrial fibrillation.”
“We saw that the benefit for patients with pre-existing atrial fibrillation was relatively large,” says Dr. Yao. “We believe that may make it particularly attractive for patients who are not able or willing to take long-term anticoagulation medication, but we should stress that we have not formally tested whether these patients can safely stop their anticoagulation.”
Based on the study, the authors concluded that among patients undergoing cardiac surgery, concurrent surgical LAAO, compared with no surgical LAAO, was associated with reduced risk of subsequent stroke and all-cause mortality. Further research, including from randomized clinical trials, is needed to more definitively determine the role of surgical LAAO.
For further information click on the link: 10.1001/jama.2018.6024