Cardiac asthma is the medical condition of intermittent wheezing, coughing, and shortness of breath that is associated with underlying congestive heart failure (CHF). Symptoms of cardiac asthma are related to the heart's inability to effectively and efficiently pump blood in a CHF patient. This can lead to accumulation of fluid in and around the lungs (pulmonary congestion), disrupting the lung's ability to oxygenate blood. Cardiac asthma carries similar symptoms to bronchial asthma, but is differentiated by lacking inflammatory origin. Because of the similarity in symptoms, diagnosis of cardiac versus bronchial asthma relies on full cardiac workup and pulmonary function testing. Treatment is centered on improving cardiac function, maintaining blood oxygen saturation levels, and stabilizing total body water volume and distribution. Signs and symptoms The most common findings of cardiac asthma are the presence of wheeze, cough, or shortness of breath (predominantly occurring at night or when laying down) in a patient that possesses signs of congestive heart failure. Additional findings consist of production of frothy or watery sputum and presence of water in the lungs that can be heard via stethoscope. In severe cases, a patient can experience multiple night time episodes of breathlessness, changes in skin coloration, and episodes of bloody sputum. Pathophysiology The underlying causes for cardiac asthma stem from the eventual back up of fluid into the pulmonary vasculature as a result of the heart's, particularly left sided, inability to effectively and efficiently pump blood. The accumulation of fluid in the heart creates a higher than normal pressure system that places increasing pressure demands on the pulmonary venous system in order for appropriate oxygenation of blood to occur. This results in what is called pulmonary venous hypertension (PVH), and results in distention and recruitment of pulmonary capillaries to help distribute the increased pressure gradient. At the capillary, there is a microvascular barrier that helps regulate fluid status via molecular pressure forces such as forces that push outward from vessels and pressures that pull or attract into vessels. With increasing PVH, pressure outward overcomes pressure inward, and fluid is distributed to the lung interstitium, preserving oxygen exchange at the capillary. Fluid is transported to the hilum and pleural space, and removed via the lymphatic system. At first, the body is capable of handling excess water. Later, the capillary vasculature is overwhelmed by increased pressure and fluid backs up into the alveolar sac, resulting in pulmonary edema and decreased