LAA closure during cardiac surgery lowers long-term stroke, mortality risk
Left atrial appendage closure during cardiac surgery was linked to reduced risk for subsequent stroke and all-cause mortality among patients undergoing cardiac surgery, according to data published in JAMA.
According to the study, many patients who undergo cardiac surgery have a history of atrial fibrillation, which is associated with increased risk for stroke. Performing left atrial appendage occlusion (LAAO) during surgery may reduce the long-term risk for stroke, the researchers wrote in the study background.
“There are limited data on the effectiveness of LAAO to guide evidence-based decision-making. A recent observational study demonstrated that LAAO was associated with a lower risk of thromboembolism in patients with AF,” Xiaoxi Yao, PhD, from the Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, Minnesota, and colleagues wrote. “However, LAAO may not be beneficial in patients without AF, but in another recent observational study, more than half of the patients undergoing LAAO did not have prior AF, perhaps indicating that pre-emptive closure in patients perceived to be at a high risk of developing AF is common practice. However, little is known whether this approach is justified.”
The researchers conducted a retrospective cohort analysis of 75,782 patients of all ages and races (mean age, 66 years; 29% women; 34% with prior AF) included in U.S. insurance databases who underwent CABG or valve surgery between 2009 and 2017. According to the researchers, 5.8% of patients who underwent cardiac surgery had concurrent LAAO.
The researchers conducted 1:1 propensity score matching to balance patients on 76 dimensions and compare those with surgical occlusion of the left atrial appendage (LAAO) against those who did not. This information was stratified by history of AF at the time of surgery.
The primary outcomes were stroke and all-cause mortality, and secondary outcomes included postoperative AF and long-term AF-related health utilization.
The propensity-matched cohort consisted of 8,590 patients followed for a mean of 2.1 years.
In the propensity-matched cohort, LAAO was associated with reduced risk for stroke (1.14 vs. 1.59 events per 100 person-years; HR = 0.73; 95% CI, 0.56-0.96) and mortality (3.01 vs. 4.3 events per 100 person-years; HR = 0.71; 95% CI, 0.6-0.84).
Yao and colleagues found an association between LAAO and higher rates of AF-related outpatient visits (11.96 vs. 10.26 events per person-year; absolute difference = 1.7; 95% CI, 1.6-1.8; RR = 1.17; 95% CI, 1.1-1.24) and hospitalizations (0.36 vs. 0.32 events per person-year; absolute difference = 0.04; 95% CI, 0.02-0.06; RR = 1.13; 95% CI, 1.05-1.21).
The study showed that the stroke event rate was 1.11 vs. 1.71 events per 100 person-years in patients with prior AF with vs. without LAAO (HR = 0.68; 95% CI, 0.5-0.92). In those with prior AF, risk for mortality was 3.22 events per 100 person-years in the LAAO group vs. 4.93 events per 100 person-years in the non-LAAO group (HR = 0.67; 95% CI, 0.56-0.8).
In patients without prior AF, researchers found that risk for stroke was 1.23 events per 100 person-years in patients with LAAO vs. 1.26 events per 100 person-years in patients without LAAO (HR = 0.95; 95% CI, 0.54-1.68), risk for mortality was 2.3 events per 100 person-years in patients with LAAO vs. 2.49 events per 100 person-years in those without it (HR = 0.92; 95% CI, 0.61-1.37), and risk for postoperative AF was 27.7% events per 100 person-years in the LAAO group vs. 20.2% events per 100 person-years in the non-LAAO group (HR = 1.46; 95% CI, 1.22-1.73).
“We saw that the benefit for patients with pre-existing atrial fibrillation was relatively large,” Yao said in a press release. “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.” by Dave Quaile
Disclosures: The authors report no relevant financial disclosures. The study was funded by the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery.