 I'm Kareem Abdul-Jabbar. I learned about atrial fibrillation the hard way. My symptoms would come and go. Shortness of breath, fatigue. I kept going. Then I got so lightheaded, I couldn't. My doctor said I have AFib, so I'm about five times more likely to have a stroke. Other symptoms, irregular heartbeat, heart racing, chest pain can come and go, but the risk of stroke stays.