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The New Frontier of Cardiac Computed Tomography Angiography: Fractional Flow Reserve and Stress Myocardial Perfusion

  • Imaging (Q Truong, Section Editor)
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Opinion statement

The increased number of patients with coronary artery disease (CAD) in developed countries is of great clinical relevance and involves a large burden of the healthcare system. The management of these patients is focused on relieving symptoms and improving clinical outcomes. Therefore the ideal test would provide the correct diagnosis and actionable information. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography (ICA), but their diagnostic yield remains low with limited accuracy when compared to obstructive CAD at the time of ICA or invasive fractional flow reserve (FFR). Invasive FFR is considered the gold standard for the evaluation of functionally relevant CAD. Therefore, an urgent need for non-invasive techniques that evaluate both the functional and morphological severity of CAD is growing. Coronary computed tomography angiography (CCTA) has emerged as a unique non-invasive technique providing coronary artery anatomic imaging. More recently, the evaluation of FFR with CCTA (FFRCT) has demonstrated high diagnostic performance compared to invasive FFR. Additionally, stress myocardial computed tomography perfusion (CTP) represents a novel tool for the diagnosis of ischemia with high diagnostic accuracy. Compared to nuclear imaging and cardiac magnetic resonance imaging, both FFRCT and stress-CTP, allow us to integrate the anatomical evaluation of coronary arteries with the functional relevance of coronary artery lesions having the potential to revolutionize the diagnostic paradigm of suspected CAD. FFRCT and stress-CTP could be assimilated in diagnostic pathways of patients with stable CAD and will likely result in a decrease of invasive diagnostic procedures and costs. The current review evaluates the technical aspects and clinical experience of FFRCT and stress-CTP in the evaluation of functionally relevant CAD discussing the strengths and weaknesses of each approach.

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Abbreviations

AUC:

Area under the curve

CAD:

Coronary artery disease

CCTA:

Coronary computed tomography angiography

CFD:

Computational fluid dynamic

CMR:

Cardiac magnetic resonance

CTP:

Computed tomography perfusion

DECT:

Dual energy computed tomography

ECG:

Electrocardiogram

Echo:

Echocardiography

FFR:

Fractional flow reserve

ICA:

Invasive coronary angiography

MBF:

Myocardial blood flow

PCI:

Percutaneous coronary intervention

PET:

Positron emission tomography

SPECT:

Single photon emission computed tomography

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Correspondence to Gianluca Pontone MD, PhD, FESC, FSCCT.

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This article is part of the Topical Collection on Imaging

Gianluca Pontone MD, PhD, FESC, FSCCT and Giuseppe Muscogiuri MD contributed equally to this work.

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Pontone, G., Muscogiuri, G., Andreini, D. et al. The New Frontier of Cardiac Computed Tomography Angiography: Fractional Flow Reserve and Stress Myocardial Perfusion. Curr Treat Options Cardio Med 18, 74 (2016). https://doi.org/10.1007/s11936-016-0493-3

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