Current and future trends in multimodality imaging of coronary artery disease

Abstract

Nowadays, there is a wide array of imaging studies available for the evaluation of coronary artery disease, each with its particular indications and strengths. Cardiac single photon emission tomography is mostly used to evaluate myocardial perfusion, having experienced recent marked improvements in image acquisition. Cardiac PET has its main utility in perfusion imaging, atherosclerosis and endothelial function evaluation, and viability assessment. Cardiovascular computed tomography has long been used as a reference test for non-invasive evaluation of coronary lesions and anatomic characterization. Cardiovascular magnetic resonance is currently the reference standard for non-invasive ventricular function evaluation and myocardial scarring delineation. These specific strengths have been enhanced with the advent of hybrid equipment, offering a true integration of different imaging modalities into a single, simultaneous and comprehensive study.

Keywords:

• cardiovascular computed tomography
• cardiovascular magnetic resonance
• coronary artery disease
• future trends
• hybrid imaging
• multimodality imaging
• myocardial viability
• positron emission tomography
• single photon emission computed tomography

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Single photon emission tomography (SPECT) myocardial perfusion imaging (MPI) studies are an accessible, economic and reliable modality to evaluate myocardial perfusion defects.

• New radiotracers, as well as novel software and equipment, such as ultrafast SPECT cameras, are being developed to improve image quality in SPECT studies.

• PET studies, although generally less accessible than SPECT MPI, are more accurate to assess myocardial perfusion defects, with the advantage of calculating blood flow in absolute terms.

• Fluorodeoxyglucose-PET is a useful tool with a high sensitivity to assess functional recovery after revascularization in viable myocardial tissue. It can also assess plaque inflammation.

• Coronary computed tomography angiography is an excellent anatomical study with a high negative predictive value, useful for safely excluding significant obstructive coronary artery disease.

• FFR_CT uses computational algorithms based on fluid hemodynamics to accurately assess the functional impact of a coronary lesion in a non-invasive manner.

• Cardiovascular magnetic resonance can provide both anatomical and functional information with high reliability without the need of submitting the patient to ionizing radiation. It can accurately assess ventricular function and delineate scar tissue.

• The advent of hybrid equipment allows for the integration of multiple studies’ strengths while potentially overcoming some of their limitations.

• The use of hybrid SPECT/CCTA imaging could theoretically obviate the need for an invasive coronary angiography without jeopardizing diagnostic accuracy.

• The choice of the study should be based on patient’s characteristics according to the clinical scenario rather than on each modality’s particular features.