COVID-19 Not Linked with Increased Thromboembolic Events in AFib Patients

A research letter published in Thrombosis Research suggests there is not a spike in thromboembolic complications in patients with atrial fibrillation (AFib) during the COVID-19 lockdown.

“AFib is a common reason for physician contact and AFib patients are often recommended treatment with oral anticoagulants to mitigate the associated risk of thromboembolic events,” the authors wrote. “Due to the COVID-19 crisis, it could be feared that patients with AF would refrain from consulting their health-care provider resulting in suboptimal care potentially reflected by an increase in the proportion of thromboembolic complications related to AFib.”

The authors used Danish nationwide administrative registries and looked at hospital contact due to thromboembolic events following Denmark’s COVID-19 lockdown in March 2020. All patients over 18 years of age with a diagnosis of transient ischemic attack or systemic embolism were included. They looked specifically the proportion of AFib-related thromboembolic events to the total amount of thromboembolic events in that period (defining AFib as a registered diagnosis of AFib prior to or in relation with hospitalization due to thromboembolic events).

According to the study results, there were 1,860 incident thromboembolic events in the study period between March and May 2020. During the same period in 2019, there were 2,067 cases of thromboembolic events. The authors reported no difference in the proportion of thromboembolic events related to AFib during the 2020 lockdown and the corresponding period in 2019 (15.7% vs. 15.6%, P=0.945). They also reported that the proportion of patients with AFib-related thromboembolic events was stable through the study period as well as the preceding weeks in both 2020 and 2019.

“Reassuringly, in a Danish context, we could not find indications that the proportion of AFib-related thromboembolic events has increased as a result of inadequate anticoagulation strategies during the lockdown period as could be feared,” they wrote. “However, it is unknown whether a delayed effect of the lockdown will be observed later on and the development in registered diseases should be closely monitored.”