EP290: Undestanding Blackouts: Causes and Treatments

Welcome to my podcast. I am Doctor Warrick Bishop, and I want to help you to live as well as possible for as long as possible. I’m a practising cardiologist, best-selling author, keynote speaker, and the creator of The Healthy Heart Network. I have over 20 years as a specialist cardiologist and a private practice of over 10,000 patients. Podcast Summary Introduction Dr. Warrick Bishop, a cardiologist, author, and CEO of the Healthy Heart Network, hosts this episode focused on understanding syncope (blackouts) and their various causes. The episode provides a comprehensive breakdown of how blackouts occur, emphasizing that many could be prevented with proper knowledge. Dr. Bishop aims to help listeners understand critical health conditions to improve their quality of life and potentially save lives. Key Takeaways: Blackouts (syncope) are a serious medical concern that can have catastrophic consequences, including falls causing fractures, motor vehicle accidents, and sudden loss of consciousness. Heart-related blackouts can stem from valve problems (such as aortic stenosis) or abnormal heart rhythms, including atrial tachycardia (fast rhythms from the upper heart) and ventricular tachycardia/fibrillation (dangerous fast rhythms from the lower heart). Slow heart rhythms or heart blocks, where the heart misses multiple beats, can also cause blackouts and require evaluation through devices like loop recorders that continuously monitor cardiac activity. Brain-related blackouts can be caused by strokes (either from blood clots or bleeding) or seizures, and may require electroencephalographs (EEGs) to assess abnormal brain electrical activity. Blood pressure drops, particularly from medication increases or dehydration, are a common cause of blackouts and are especially problematic in neurological conditions like Parkinson's disease. Vasovagal episodes (simple faints triggered by the vagus nerve and parasympathetic nervous system) are the most common cause of blackouts and are typically preventable and less concerning for driving privileges. Distinguishing between different causes of blackouts is critical because heart and brain-related syncope may require temporary suspension of driver's licenses until proper diagnosis is confirmed. The parasympathetic nervous system (the "rest and digest" response) can lower heart rate and blood pressure so significantly that profound vagal responses trigger loss of consciousness.