SN instructed patient / caregiver that Atrial fibrillation is an irregular and often rapid heart rate that can increase your risk of stroke, heart failure and other heart-related complications. It may lead to complications. Atrial fibrillation can lead to blood clots forming in the heart that may circulate to other organs and lead to blocked blood flow ( ischemia ). Treatments for this may include medications and other interventions to try to alter the heart's electrical system. Signs and symptoms ( S / S ) such as: Palpitations, which are sensations of a racing, uncomfortable, irregular heartbeat or a flip - flopping in your chest, weakness, fatigue, lightheadedness, dizziness, chest pain.