Epidemiology

Etiology

An accumulation of low-protein fluid in the interstitium and alveoli due to an increase in pulmonary capillary hydrostatic pressure

Causes of acute heart failure (left ventricular systolic and/or diastolic dysfunction), e.g.: Acute coronary syndrome
Valvular dysfunction, e.g.:
- Aortic regurgitation or stenosis
- Mitral regurgitation or stenosis
Cardiac arrhythmia

An accumulation of protein-rich fluid in the lung interstitium and alveoli due to an increase in permeability of the pulmonary capillaries

PFT Parameter	Change in Pulmonary Edema	Rationale
FVC	↓	Fluid in alveoli reduces displaceable air volume.
FEV1	↓	Reduced proportionally with FVC.
FEV1/FVC Ratio	Normal or ↑	Characteristic of a restrictive pattern.
TLC	↓	Hallmark of restriction; lungs can’t fully expand.
DLCO	↓ (usually)	Increased diffusion distance across fluid-filled alveolar-capillary membrane.
Compliance	↓	Lungs become stiff and difficult to inflate.