Pulmonary embolism: filling defect

Thrombotic pulmonary embolism obstructs part of the pulmonary arterial bed. On CT angiography, thrombus appears as a defect within contrast-enhanced blood.

Check enhancement and artefacts before following arteries through consecutive slices. Compare reconstructions with the full series.

Both views show lower-attenuation areas within enhanced arteries. The original case describes a saddle embolus with bilateral extension.

Relate the radiological diagnosis to clinical probability and thromboembolic context. This image alone establishes neither clot origin nor age.

Contrast mixing, respiratory motion and partial-volume effects can mimic a defect. Multiplanar review of consecutive images is necessary.

Document blood pressure, oxygenation and right ventricular dysfunction; biomarkers and clinical scores complement risk stratification.

Persistent hypotension, shock or cardiopulmonary deterioration requires urgent care. Reperfusion decisions depend on specialist risk assessment.

A saddle embolus alone does not classify severity. These two views cannot reliably measure ventricular ratio or exclude other emboli.

Recognise the filling defect, confirm it on the full study, then assess clinical tolerance and the right heart.

• AHA/ACC — Acute pulmonary embolism guideline: key points (2026) ↗
• Myat & Ahsan — Pulmonary embolism: original image and case report (2007) ↗
• Aung Myat et Arif Ahsan — document iconographique original / original image ↗

Documentary review: 2026-10-16