probably other lifestyle factors during stress like sleep disturbance, alcohol consumption, high blood pressure etc.
Garg PK, Claxton JS, Soliman EZ, et al. Associations of anger, vital exhaustion, anti-depressant use, and poor social ties with incident atrial fibrillation: The Atherosclerosis Risk in Communities Study. Eur J Prev Cardiol. 2020. doi:10.1177/2047487319897163.
Burnout could result in increased circulating catecholamines due to stress which may perhaps induce structural vascular and myocardial changes within the pulmonary veins and posterior left atrial wall. Increased fibrosis in there can result in the creation of ectopic atrial beats.
That's just my idea but i am not certain it occurs.