The number of patients with atrial fibrillation (AFib) in the United States is growing more rapidly than expected, and it’s predicted to affect over 12 million Americans by the year 2030. Changes in the rhythms of your heartbeat can begin for different reasons and produce varied and sometimes serious health risks. At this time, AFib is linked to the deaths of nearly a quarter million Americans each year.
Sometimes people know when they are having AFib or are “in AFib.” Much of the time, however, AFib is “silent,” and undetectable. Silence, however, doesn't mean safety. Any risk factors and possible symptoms of AFib can ultimately mean an increased risk of stroke as well as other cardiac diseases.
Increased urinary frequency can be an underrecognized symptom of AFib. If you find you’re having to urinate more frequently or in larger amounts than usual, it may be a sign your heart health could be compromised by otherwise undetectable changes in the body.
AFib loses the beat
Most adults know the heart is a pump made of muscle that circulates oxygen-rich blood around the body with each heartbeat. Its uniqueness also lies in its electrical system, generating its own chemical electricity using special myocytes (muscle cells). One key group of these myocytes is the sinoatrial (SA) node, which produces our heartbeat, about 60 to 100 times per minute in adults throughout their lives.
The electrical stimulus from the SA node causes shifts in electrolytes (calcium, potassium and sodium), so the muscles of the heart contract and release rhythmically and in order. In atrial fibrillation, the atria (two upper chambers of the heart) become disorganized and chaotic in their rhythms. This irregularity can be continuous or intermittent (off and on); it can go away on its own, go away and come back or be permanent.
Origin of chaos: risk factors for AFib
There are many risk factors for AFib. Two of the most common include hypertension (which alone accounts for 20% of AFib cases) and advancing age (once over 45 years old, the odds of developing AFib jump to 1 in 3-5 people). Obesity, European descent, heart failure, diabetes and chronic kidney disease (CKD) are large contributors to AFib risk.
Factors you’re born with can play a role, such as heart defects or a family history of atrial fibrillation. Other heart problems like coronary artery disease (CAD), ischemic heart disease, sick sinus syndrome and enlarged left chambers of the heart can increase the risk of AFib. What’s more, conditions outside the heart like hyperthyroidism, electrolyte imbalances, lung disease and obstructive sleep apnea (OSA) can increase your chances of developing AFib. Lifestyle risk factors include smoking, drug use (including caffeine and nicotine), excessive alcohol use and stress.
Stroke of bad luck
Stroke presents a very real danger in the setting of AFib. Because the atria of the heart are beating chaotically and out of rhythm, blood can begin to pool within the atria instead of moving through quickly, as it should. Clots can form, and if the clots reach other parts of the body, dangerous loss of blood flow (ischemia) can occur at that location. A clot that reaches the brain and starves a part of it for oxygen can cause a stroke. Two-thirds of strokes are caused by clots, the other ⅓ by hemorrhage. The clot-affected part of the brain can become severely damaged and die from lack of oxygen. AFib causes almost 15% of strokes, and AFib strokes tend to be among the most damaging. AFib is also linked to an increased risk of having a heart attack or of developing heart failure, cognitive decline or dementia.
A stroke can greatly lessen your ability to function independently and negatively impact your quality of life for weeks, months, years - even forever. Since stroke occurrence and damage can be hard to predict, the implications are huge and prevention is crucial. Sadly, some researchers have found many elderly people indicated they would rather have died from their stroke than live with a severe disability following one. Staying alert to any potential risk of stroke can preserve your quality of life as you age. Getting familiar with both the common and uncommon symptoms of AFib can protect your ability to live a life you love.
Hiding in plain sight: symptoms of AFib
While there are many ways to develop AFib, it can easily slip past your awareness, without symptoms and undetectable even on an electrocardiogram (EKG). Common symptoms include irregular heartbeat as well as feeling short of breath, “winded,” or extremely tired. Lightheadedness can be a clue, as can sweating, heart palpitations or chest pain.
Because of the unique relationship between a peptide released in the atria during AFib and your bladder, increased urination can also be a not-so-subtle sign of AFib. Many of these symptoms can also be symptoms of other conditions, which makes it even more important to get checked by your doctor and possibly a cardiologist. He or she may decide to have you use a heart monitor over a period of weeks to make sure your heart rhythms stay in check.
Strange bedfellows
Researchers noted decades ago that up to 70% of AFib episodes are linked to an increase in urine production. In the early 1980s, they affirmed atrial natriuretic peptide (ANP) as the cause. During AFib, the quivering muscles of the atria release ANP and can cause the urge to urinate as often as every 20 minutes. Since AFib often occurs at night, follow up on any increased waking up to pee.
ANP is released whenever the atria expand to accommodate increased fluid, and the peptide signals your kidneys to rebalance by getting rid of excess water from the body as urine. ANP also rises in patients with hypertension, congestive heart failure and a history of myocardial infarction (heart attack). People with these conditions benefit when excess fluid leaves the body, allowing the heart to pump blood efficiently by lightening its workload. Though it may seem like “business as usual” - just more of it, tuning in to and reporting changes in your bathroom habits to your healthcare provider could reveal hidden and very treatable health hazards.
References
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