known issue heart valves severe chronic obstructive pulmonary disease copd experiencing shortness breath difficulty breathing significant way feel slightly dizzy lightheaded heart attack angina chest pain known heart defect feel heart beating fast racing irregularly missing beat feel palpitations traveled country last 4 weeks
psvt anemia guillain-barré syndrome myocarditis atrial fibrillation scombroid food poisoning acute dystonic reactions myasthenia gravis possible nstemi / stemi panic attack
Atrial fibrillation