Diagnostic Capabilities of Chest CT Angiography

Primary Vascular Pathologies

The American College of Radiology recommends CT pulmonary angiography (CTPA) as the primary imaging modality for evaluating suspected pulmonary embolism, demonstrating both acute and chronic thromboembolic disease, with excellent spatial resolution and detailed evaluation of lung parenchyma 1
CTPA provides accurate detection of recurrent or residual pulmonary embolism, with central disease better identified on CT compared to conventional pulmonary angiography (accuracy 0.79 vs 0.74) 1
The American College of Cardiology states that CTA is the essential imaging tool for diagnosing aortic dissection with greater than 95% accuracy, providing excellent definition of the intimal flap, false and true lumens, and intra-aneurysmal thrombus 2
Aortic aneurysms are readily identifiable using CTA, which defines maximal diameter and monitors expansion over time, according to the American Academy of Family Physicians 3

Coronary CT angiography (CCTA) demonstrates 90-95% or greater sensitivity and specificity for obstructive coronary artery disease when using dedicated ECG-gated protocols, as recommended by the American College of Cardiology 4
CCTA has excellent negative predictive value (94-99%), making it highly effective for excluding significant coronary disease, according to the American College of Cardiology 5
The American College of Radiology states that CCTA can diagnose atherosclerotic plaque, coronary stenosis, coronary dissection, and congenital coronary anomalies 6

CTA is 95% sensitive and 100% specific for diagnosing Takayasu arteritis, outperforming catheter-based angiography, as reported by the American College of Radiology 7
Wall thickness measured by CTA is 67% sensitive and 98% specific for identifying giant cell arteritis, according to the American College of Radiology 7

Multidetector CT readily identifies findings associated with pulmonary hypertension, such as pulmonary artery enlargement and associated right heart changes, as stated by the American Academy of Family Physicians 3

Heavy coronary calcification limits assessment of stenosis severity and reduces specificity, while high or irregular heart rates cause motion artifacts that can falsely suggest stenosis, according to Praxis Medical Insights 5
Modern CCTA techniques have significantly reduced radiation exposure to 1.1-2.9 mSv using prospective triggering and iterative reconstruction, as reported by Praxis Medical Insights 5

The American College of Cardiology recommends against using standard non-ECG-gated chest CTA for detailed coronary artery assessment, as dedicated coronary CTA with ECG-gating is required for accurate coronary evaluation 5
Praxis Medical Insights warns that anatomic stenosis on CTA does not always correlate with hemodynamic significance, and functional testing may be needed for intermediate stenoses 8