Dyspnea is a common complaint in the emergency room (ER) and is a challenge when presented as a cardinal symptom in patients with clinical stability. It is also called shortness of breath, and the definition includes a subjective perception of not being able to breathe adequately, whether accompanied by signs of respiratory distress or not. To assess patients with dyspnea, full clinical history and physical examination are imperative since there are clues that can be easily overlooked in the ER. The most common causes of dyspnea are chronic obstructive pulmonary disease, heart failure, and pneumonia. Physicians in charge also should considerer ischemic heart disease, pulmonary embolism, and myocarditis in elderly and young population. A chest X-ray is a cornerstone to identify the cardiac or pulmonary origin. The initial approach to a dyspneic patient should always focus on its clinical stability and the management of the airway. B-type natriuretic peptide <100 pg/dL excluded heart failure, D-dimer <500 ng/dL excluded pulmonary embolism, and a high-sensitive troponin assays with a coefficient of variance of <10% at the 99th percentile value, type 1 or 2 myocardial infarction, or myocardial injury. Anxiety is the last diagnosis after a careful cardiac ruled out. The evaluation of dyspnea in the ER is complex and should be addressed promptly and efficiently, to avoid life-threatening situations. This chapter will focus on the cardiac causes of dyspnea.
