The potential role for the use of cardiac computed tomography angiography for the acute chest pain patient in the emergency department: A cautionary viewpoint

Unquestionably, CCTA is a powerful new tool in our diagnostic armamentarium, with an outstanding ability to detect or exclude the presence of coronary artery stenoses. However, the inability to provide the physiologic significance of such a lesion may limit its value in the setting of acute chest pain, as it is "...the presence of ischemia rather than the presence of a stenosis (that) is essential for good clinical decision making". 31 The limitations inherent in the technique or patient-based contraindications also limit the use of CCTA for all ED, potentially being unsuitable for a definitive diagnosis in one-third to one-half of acute chest pain patients. These include: (1) ectopy (atrial fibrillation, ventricular ectopy), which limit the ability to synchronize the image acquisition of the beating heart, (2) contrast-related factors (renal insufficiency, allergy, metformin use, etc.), and (3) inability to administer betablockers (asthma). CCTA limitations, both real and potential, are summarized in Table 2. In conclusion, CCTA should be considered for the rapid triage of chest pain patients in the ED, especially those at low and intermediate risk for an acute coronary syndrome, as confirmed by the recently published appropriate use criteria.32 However, it cannot be advocated as a standard approach for all patients, as those at high risk may have confounding variables (i.e., coronary calcification) and may require delineation of coronary physiology. Finally, the technical and patient-related limitations preclude the use of a CCTA strategy for all chest pain patients, thereby mandating alternative approaches including rest radionuclide imaging and immediate exercise testing. © 2010 American Society of Nuclear Cardiology.