Some of the more well-known symptoms of heart failure include shortness of breath, difficulty breathing when lying down, and a cough, according to Eva Shelton, MD, an internal medicine physician at Brigham and Women’s Hospital. “There are two major types of heart failure physiology, left-sided and right-sided heart failure,” Shelton explains. “When left-sided heart failure occurs, blood and the fluid it contains backs up into the lungs, resulting in shortness of breath and cough.” But since a cough can indicate the onset of many conditions, ranging from the common cold to thyroid problems, how can you tell when it’s actually a sign of heart disease? Read on to find out. READ THIS NEXT: If Your Legs Feel Like This, Get Your Heart Checked. When blood backs up in the lungs due to heart failure, the leaked fluid “essentially makes the lungs feel like they’re drowning,” explains Shelton. “The lungs feel irritated and try to expel that water, so the natural response is to cough. Because this cough is a result of fluid build up in the lungs, it generally sounds ‘wet.’ It sounds like there is some water [and/or] sputum in the cough.” Although a wet cough may indicate heart disease, a dry, wheezing cough can be a symptom, too. “There are also situations in which the lungs are not able to get as much fluid out, so the cough sounds more dry,” warns Shelton. This is known as cardiac asthma. “Heart failure can cause fluid to build up in the lungs (pulmonary edema) and in and around the airways,” according to the Mayo Clinic. “This can cause shortness of breath, coughing and wheezing similar to the signs and symptoms of asthma.” If your cough produces bloody or pink mucus, this could be a symptom of heart failure, reports the American Heart Association. This happens when your heart can’t keep up with the supply of blood, which then “backs up” in the vessels (pulmonary veins) that transfer blood from the lungs to the heart. The mucus may also appear frothy or white.ae0fcc31ae342fd3a1346ebb1f342fcb For more health news sent directly to your inbox, sign up for our daily newsletter. When the lungs are affected by fluid building up and the resulting cough wakes you up during the night, this may be paroxysmal nocturnal dyspnea (PND) according to Verywell Health: “[PND] is characterized by being awakened during sleep with severe shortness of breath, gasping for air, coughing, and feeling the need to sit up, stand up, and/or open a window for air—all of which may help improve breathing after a few minutes.” “I have met patients who were first diagnosed as having a respiratory issue,” heart failure specialist Miriam Jacob, MD, told the Cleveland Clinic. “Over time, when their symptoms didn’t improve with appropriate treatment, heart failure was entertained as a diagnosis.” The most common reasons for a long-term cough are asthma or chronic obstructive pulmonary disease—two conditions that cause inflammation in the lungs which can be treated, reports the Cleveland Clinic. If a persistent cough continues even after treatment for these issues, heart disease may be the cause. The same buildup of fluid that causes you to cough may also result in a feeling that Medical News Today describes as akin to “cracking, gurgling, or as if a bubble is about to burst.” Shelton recommends that if you’re experiencing this or any other symptom(s) of heart disease to speak with your doctor in order to evaluate, and possibly treat, the condition. “In the interim for symptom management, it can help to sleep reclined so you don’t have as much shortness of breath lying down, elevating the legs to help with edema, oxygen therapy to help lungs oxygenate, not exerting yourself too much, etc.,” she advises.