Multimodality Cardiac Imaging — a Complex Interdisciplinary Approach Resulting from the CARDIO IMAGE Project

Abstract

Given the multitude of complex and reliable information provided in different clinical settings, cardiac imaging became nowadays an indispensable tool for clinical practitioners and for clinical researchers as well. Invasive and noninvasive technologies have been developed in order to provide the clinicians with the necessary information on cardiovascular structure and function, required for choosing the best therapeutic approach in patients with heart diseases. In line with the modern technological developments, sophisticated imaging methods were implemented in the recent years, able to offer a more complex panel of data regarding heart structures and vascular system, methods which have been validated as cutting-edge technologies and golden-standard techniques, not only for clinical routine, but also for research applications.Invasive cardiac imaging is a tool mainly dedicated to the assessment of coronary vessels during coronary angiography or coronary revascularization procedures. Apart from the classical coronary angiography, such modern invasive imaging tools include optical coherence tomography (OCT), intravascular ultrasound (IVUS) and nearinfrared spectroscopy (NIRS), all of them being frequently used not only for assessment of the severity of a coronary stenosis, but also for estimation of plaque vulnerability, especially in acute settings. However, their role in the evaluation of coronary lesions started to decline in parallel with the rapid development of noninvasive techniques for the visualization of coronary plaques, represented mainly by cardiac computed tomography angiography (CCTA). Being able to provide accurate data regarding stenosis severity and plaque structure and vulnerability, this technique replaced nowadays not only the invasive intracoronary techniques, but also the coronary angiography as a routine method for the visualization of the coronary tree.However, despite being extremely useful for the estimation of the severity of coronary artery diseases on a large scale, none of the above mentioned methods is able to provide a simple information, which is critical for the therapeutic decision, represented by the functional significance of a coronary stenosis. Therefore, new techniques have been developed in order to offer a complex multimodality approach that would be able to answer this question.The functional significance of a coronary stenosis can be assessed nowadays directly or indirectly, using invasive or noninvasive tools. Invasive determination of the fractional flow reserve (FFR) has been validated as a gold-standard technique for the estimation of the functional impact of a coronary stenosis, serving as a useful clinical decision tool. The invasive evaluation of FFR tends to be replaced by noninvasive evaluation using the so-called FFRCT, which implies the determination of the fractional flow reserve remotely, noninvasively, using computational flow dynamics for simulations of the coronary flow. Other imaging-based