An Unusual Symptom While You Sleep Could Mean You Have Left-Sided Heart Failure

People with heart failure don't always experience obvious symptoms. In some cases, they may mistake common signs like fatigue and coughing for another condition, such as a respiratory illness. But you shouldn't ignore warning signs of heart disease that persist, because it could be your body's way of alerting you to see a doctor.

One of those surprising warning signs is an inability to rest comfortably. If you find yourself short of breath when you wake up, or if you have difficulty sleeping flat on your back, it could be indicative of left-sided heart failure. That breathless feeling that occurs when you lie down is called orthopnea, and could be indicative of fluid retention in the lungs. Dr. Andrew Freeman, M.D., a cardiologist at National Jewish Health, tells Everyday Health, "Patients will often tell me, 'I need to prop myself up on four pillows to fall asleep.'"

If you find that you can't fall asleep without elevating your head in a manner that's different from what you would normally do, that might be a sign that it's time to see a cardiologist — especially if you cough constantly. It's worth stepping on the scale, too, because any fluid accumulation will cause the number to creep up. "If your weight goes up two or three pounds in a day or five or six pounds in a week, it's almost always water," explains Dr. Freeman. "That's a reason to get in touch with your doctor."

Heart failure is one of the most common conditions in the world. There's a misconception that the diagnosis, which affects some 64 million people globally, means that the heart will completely stop functioning properly. In fact, heart failure occurs when the organ doesn't pump blood efficiently to other areas of the body. "Heart failure is not a death sentence," clarified Dr. Fatima Rodriguez, M.D., an Associate Professor of Medicine at Stanford University. "It can be managed as a chronic disease with appropriate use of medications and lifestyle changes."

Notably, there are also different types, the most common of which is left-sided heart failure. Doctors make a diagnosis based on which side of the heart is primarily affected by the organ's inability to pump blood properly. In people with left-sided heart failure, naturally, the left side weakens. Under normal circumstances, it effectively pumps oxygenated blood to other organs in the body by traveling from the lungs to the left atrium and finally to the left ventricle.

The left ventricle is typically a workhorse, pumping at elevated pressures to efficiently deliver blood throughout the body. Proper functionality is vital for optimal health. In people with left-sided heart failure, it works harder than it usually would to deliver blood. When the left ventricle doesn't contract as normal, it's known as systolic failure. Those with diastolic failure, meanwhile, experience stiffening of the heart muscle.

The rule of thumb to remember is that left-sided heart failure largely affects the lungs, while right-sided heart failure has an impact on other parts of the body. In patients with the former, it's not unusual to experience overall fatigue. That's due not just to poor sleep quality, which could be the primary symptom that reveals there is an underlying health problem, but also to a lack of oxygen-rich blood traveling throughout the body. (Here are some surprising things your sleep habits can reveal about your health.)

Right-sided heart failure can occur as a result of left-sided heart failure, largely because as fluid accumulates in the lungs, it forces the right ventricle to work harder than it normally would to do its job. This can lead to eventual failure, which can cause symptoms like fluid retention in the legs, feet, and ankles. By contrast, coughing and shortness of breath are less likely to occur when the condition affects the right side.

If ever in doubt, it's always best to seek medical guidance. Symptoms like fatigue and exhaustion when performing everyday activities may often be chalked up to normal signs of aging, but could actually be related to heart function. A cardiologist can perform a battery of tests to evaluate your heart health.