Pulmonary Embolism - Diagnostic Modalities
Diagnostic Modalities to Identify Pulmonary Embolism
V/Q Scan (ventilation to perfusion scan)
- Nuclear medicine imaging, which identifies a mismatch between ventilation and pulmonary vascularization (perfusion).
Chest CT w/angiography
- Contrast material in the blood vessels allows for visualization of a filling defect: disruption of blood flow within the pulmonary arteries.
Chest X-Ray
Signs of PE include:
- Atelectasis
- Hampton hump
- Westermark sign, which is indicative of oligemic areas (poor perfusion of pulmonary arteries).
- Pulmonary effusion
ECG
Signs of PE include:
- Sinus tachycardia
- S wave in lead 1 with inverted Q and T waves in lead III (S1Q3T3 sign).
Histopathology
- Thrombi formed premortem display lines of Zahn, which are formed by layers of fibrin, red blood cells, and platelet deposition.