My father had it with the silent afib. His doctor wanted a stress test done because of his family history of heart attacks and strokes in their 50s. The test showed the afib and get then had a quadruble bypass. My mother also had afib, but hers was from rheumatic fever as a child that caused scar tissue to block the heart valve. Afib can come from any stressor on the heart. It can also come from a faulty connection within the heart that regulates the heartbeat.