CT in Acute Chest Pain

Summarized by: Vineeth Bhogadi, M.D.

Reviewed by: Elton Law, M.D.

Original publication details

Authors: Seung Min Yoo 1, Eun Ju Chun, Hwa Yeon Lee, Daniel Min, Charles S White

DOI: https://doi.org/10.1097/rti.0000000000000241

Reference: Yoo, S. M., Chun, E. J., Lee, H. Y., Min, D., & White, C. S. (2017). Computed Tomography Diagnosis of Nonspecific Acute Chest Pain in the Emergency Department: From Typical Acute Coronary Syndrome to Various Unusual Mimics. Journal of thoracic imaging, 32(1), 26–35.

Overview

Five choices of CT protocols used for acute chest pain in the ED

  1. Aortic CTA

  2. Pulmonary arterial CTA

  3. Coronary CTA

  4. Triple rule-out

  5. Routine CT chest 

Choice of CT protocol should be made based on objective assessment of pretest probability of the 3 major diagnosis of acute coronary syndrome (ACS), pulmonary embolism (PE), aortic dissection.

Nonspecific Acute Chest Pain

High suspicion of aortic dissection or PE

Dedicated PE or aortic CTA should be performed. TRO is not adequately tailored for these disease entities.

Low clinical suspicion of ACS + Normal troponins

Dedicated coronary CTA or TRO can be performed to differentiate ACS from mimics. The appropriateness of TRO is uncertain in the 2012 ACCF guidelines and should be used with caution due to its high radiation dose. PE and aortic dissection can most often be diagnoses missed on coronary CTA.

Increased troponins and normal coronary angiography

Broad differential including Type A dissection, non-obstructive infarction, myocarditis etc. CT protocol should cover entire chest with good enhancement of pulmonary arteries and aorta.

Normal Troponins and normal coronary angiography

CT with Z-axis coverage to include upper abdomen to differentiate mimics of ACS.

Typical CT findings of ACS

Primary role of coronary CTA in ED is to exclude ACS in patients with low-intermediate risk due to a high negative predictive value. Moderate specificity for ACS due to blooming/motion artifact

Acute MI coronary CTA findings include critical stenosis (>70%) by mixed/non-calcified plaque and the presence of wall motion abnormalities if CTA was performed with retrospective gating.

Mimics of ACS with troponin rise

Aortic dissection with coronary involvement

The presence of coronary artery involvement by intimal flap extension can be precisely determined if ECG gating is used.

PE with myocardial injury

typically seen with massive or sub-massive PE

Stress induced cardiomyopathy

No universally accepted diagnostic criteria. Apical ballooning of LV that extends beyond a vascular territory and preserved /hyperdynamic contraction in the base of the heart on CT/MR/Echo should be present to make diagnosis. Cardiac CT with retrospective ECG gating has the potential to precisely evaluate coronary anatomy and LV wall motion abnormalities. Cine imaging is essential to identify stress-induced cardiomyopathy.

Cardiac inflammatory disease

Delayed CT (typically at 5 minutes) is required to identify typical subepicardial patch delayed enhancement and has diagnostic accuracy comparable to delayed enhancement MR in the diagnosis of myocarditis. Typical CT findings of pericarditis include pericardial effusion with enhancement of the pericardium.

Mimics of ACS with normal troponin

Epicardial Fat Necrosis

CT findings include encapsulated fatty lesion with inflammatory changes including paracardial fat standing, pericardial thickening, and small left pleural effusion.

MSK etiologies

Rib fractures

Abdominal mimics of ACS

Require evaluation of abdominal organs and esophagus. Typical mimics include reflux esophagitis, pancreatitis etc.

Citation


Yoo, S. M., Chun, E. J., Lee, H. Y., Min, D., & White, C. S. (2017). Computed Tomography Diagnosis of Nonspecific Acute Chest Pain in the Emergency Department: From Typical Acute Coronary Syndrome to Various Unusual Mimics. Journal of thoracic imaging, 32(1), 26–35.