Evaluation of Myocardial Perfusion by Computed Tomography - Principles, Technical Background and Recommendations

Abstract

Coronary computed tomography angiography (CCTA) has gained a prominent role in the evaluation of coronary artery disease. However, its anatomical nature does not allow the evaluation of the functional repercussion of coronary obstructions. It has been made possible to evaluate Myocardial computed tomography perfusion (Myocardial CTP) recently, based on myocardial contrast changes related to coronary stenoses. Several studies have validated this technique against the anatomical reference method (cardiac catheterization) and other functional methods, including myocardial perfusion scintigraphy and fractional flow reserve. The Myocardial CTP is performed in conjunction with the CCTA, a combined analysis of anatomy and function. The stress phase (with assessment of myocardial perfusion) can be performed before or after the resting phase (assessment of resting perfusion and coronary arteries), and different acquisition parameters are proposed according to the protocol and type of equipment used. Stressors used are based on coronary vasodilation (e.g. dipyridamole, adenosine). Image interpretation, similar to other perfusion assessment methods, is based on the identification and quantification of myocardial perfusion defects. The integration of both perfusion and anatomical findings is fundamental for the examination interpretation algorithm, allowing to define if the stenoses identified are hemodynamically significant and may be related to myocardial ischemia.

Risk Factors for Acute Renal Failure after Cardiac Catheterization Most Cited in the Literature: An Integrative Review

“…It is known that in order to perform cardiac catheterism, iodinated contrasts are necessary to visualize the coronary arteries with the aim of diagnosis or treatment [29].…”

Menor Prevalência e Extensão da Aterosclerose Coronária na Doença de Chagas Crônica por Angiotomografia Coronária

“…Por outro lado, a avaliação do ECC, somada à ATC, não somente é capaz de identificar lesões obstrutivas, [33][34][35][36][37] como também permite a avaliação quantitativa da "carga" aterosclerótica global do indivíduo. [38][39][40][41][42][43] Assim, trata-se de um instrumento muito mais sensível para a detecção de DAC, particularmente em estágios mais precoces da doença, nas quais a angiografia coronária invasiva pode perder o diagnóstico.…”

One-Stop Shop para Imagens Cardiovasculares Não Invasivas?

“…4 CCTA combined with stress tomography evaluation of myocardial perfusion (CTP) is an accurate modality to determine regional myocardial flow repercussions of coronary stenosis, though it usually requires additional acquisition and is still underused. 5 Derived flow fractional reserve -computed tomography (FFR-CT) is another "physiologic" CT approach in which computational fluid dynamics is applied to standard CCTA data and has emerged as a promising tool for the functional assessment of coronary stenosis. The diagnostic value of remotely performed FFR-CT has been prospectively validated in several large multicenter studies, but requires the use of offsite supercomputers, which can be time-consuming and cost-intensive, limiting its widespread clinical utility.…”