Heart Failure and Acute Pulmonary Edema (APEd)

Heart failure (HF) is a complex syndrome in which the cardiac output cannot meet the demand, i.e., metabolic needs of the tissues and reflect the impairment of the heart's pump function. This condition is also referred to as congestive heart failure (CHF) as it is mostly associated with fluid retention.

The four main factors that determine the pump function of the left ventricle, which are contractility (contractility), preload, afterload and heart rate.

Accepted guidelines divided patients with HF into three groups according to their left ventricular ejection fraction (EF). The group with a EF below 40% continues to be known as a “low/reduced EF” (HF-REF), and a group of 50% and above remains “preserved EF” (HF-PEF), while a group of 40–49% is at the border (mid-range), thus it was named mildly reduced EF” (HF-MREF). The incidence of HF-PEF increases with age. The majority of cases in the elderly is due to HF-PEF. Acute decompensated HF is a deadly cause of cardiac dysfunction that can present with acute respiratory distress. There are many different causes of APEd, though cardiogenic pulmonary edema is usually a result of acutely elevated cardiac filling pressures. Clinical findings develop as a result of impaired perfusion and/or venous distension, with resultant surge in pressure. The patient mostly present with progressive symptoms of HF or acutely appeared signs of left-sided decompensation.

Patients who are diagnosed with HF for the first time and who is admitted with APEd should be hospitalized and treated accordingly. HF develops in 10 to 20% of AMI cases. Since this group has a high mortality, it must be identified and treated. The main objective of the treatment in the Acute Left HF is to provide the respiratory and cardiovascular stability as soon as possible. The main goal is to “dry” the lungs, not just throwing off water.

COVID-19 pneumonia and respiratory distress can masquerade APEd in the pandemic period. Most “typical” radiological findings including ground-glass opacities are common in both entities. It is very frequent that a clinician mixes up the two entities, especially misinterpret APEd as COVID-19, because the outbreak affects so many people that every physician is conditioned to see the viral pneumonia. Therefore, educational resources should stress on how to implement correct differential diagnosis of cardiopulmonary entities including AHF/APEd in the pandemics in both hospital and outpatient conditions. This chapter provides a general overview of the diagnosis and management of HF and APEd with a special emphasis on the acute presentation in the pandemic era.

Keywords: Acute pulmonary edema, Congestive heart failure, COVID-19, Dyspnea, Heart failure, Left ventricular dysfunction.