Asthma can be triggered by stress.and anxiety and exercise. Exercise and extreme activity level can cause rapid heart palpitations or the feelings of the heart racing or pounding.; which in turn exacerbates the asthmatic attacks. The symptoms you describe; e;g; SOB with mild exertion, and heart palpitations might just be an anxiety behavioral disorder. Or it could be the side effect of the asthmatic drugs. Pls review my detailed answer. Palpitations are heartbeat sensations that feel like pounding or racing. Does your heart rate feel slow or fast when you have these hard palpitations? Heart palpitations can be caused by: Exercise Anxiety, stress, fear Fever Caffeine, nicotine, cocaine, diet pills Overactive thyroid Anemia Hyperventilation Low levels of oxygen in your blood Medications such as thyroid pills, asthma drugs, beta blockers for high blood pressure or heart disease, or anti-arrhythmics (medications to treat an irregular heart rhythm can sometimes cause a different irregular rhythm) Mitral valve prolapse -- the valve that separates the left upper chamber (atrium) from the left lower chamber (ventricle) of the heart does not close properly Heart disease. Shortness of breath (SOB) from heart failure Depending on the stage of heart failure, shortness of breath may occur: With exertion or exercise. At rest. While lying down (orthopnea). This often is relieved by sitting up or standing. At night, and it may occur with waking up coughing and/or wheezing, having a rapid heart rate, and a feeling of being suffocated (paroxysmal nocturnal dyspnea or PND) What characterizes shortness of breath from heart failure? People with heart failure experience shortness of breath in many different ways. Most people describe it as being winded, having a tightness in the chest, or even feeling tired while walking. You may also experience shortness of breath from heart failure at specific times—when you exercise or overexert yourself, while you are lying down, and while you are sleeping. Shortness of breath from exertion. If your shortness of breath is not severe, you may notice it only when you are exerting yourself, and sometimes only during more intense exertion. For example, you may notice that you are short of breath after walking up three flights of stairs, whereas before, you were comfortable walking up four flights. The medical term for this symptom is dyspnea (DISP-nee-ah). When heart failure develops gradually, your shortness of breath also may develop gradually, which can make it hard to notice. People with more severe heart failure, however, may experience shortness of breath with minimal exertion, even from just combing their hair. In the most severe cases, shortness of breath can become so serious that you require continuous oxygen therapy. Shortness of breath while lying down. People with more severe heart failure may experience shortness of breath when they lie down. The medical term for this symptom is orthopnea (or-THOP-nee-ah). The severity of this symptom usually depends on how flat you are lying—the flatter you lie, the more you feel short of breath. To gauge the severity of this symptom, doctors often ask people how many pillows they need to lie on to avoid feeling short of breath in bed. For example, three-pillow orthopnea is worse than two-pillow orthopnea because you have less tolerance for lying flat. The reason you may have orthopnea is that when you lie flat, the blood that ordinarily pools in the veins of your legs is reentering your bloodstream. If you have heart failure, your heart may not be able to keep up with the increased amount of blood returning to the heart, so fluid builds up inside the lungs and causes shortness of breath. Shortness of breath while sleeping. Some people with heart failure wake up in the middle of the night with severe shortness of breath. The medical term for this symptom is paroxysmal nocturnal dyspnea (PND). In general, people who experience PND do not feel increased shortness of breath when they first lie down. However, after several hours of lying down, they awake with shortness of breath, which often occurs suddenly. People who experience PND often have to sit up on the side of the bed, and they may feel a need to open a window to get more air. The shortness of breath generally goes away after a few minutes of sitting up. While shortness of breath is the most common symptom of heart failure, it may be difficult or impossible to distinguish it from shortness of breath caused by other health problems such as emphysema or severe anemia. Your doctor can help you determine why you have been feeling short of breath. Based on the above, it might be a very good idea to go and be checked by a cardiologist to determine if your heart palpitations along with SOB or dyspnea with mild exertion are indeed due to early signs of heart failure. He ll most likely do an EKG and a cardiac stress testing or treadmill test. even an Echocardiogram. I have an extensive nsg experience work hx in taking care of cardiac patients. And I also have asthma and a bad heart. No, I don t think your symptoms are due to the more severe diagnosis of cardiomyopathy (weakness of cardiac muscles) for which heart transplant is the only recourse. I hope you find this thorough answer helpful. Good Luck!!!