IJCS | Volume 32, Nº2, March/April 2019

181 Figure 2 - Myocardial tagging for quantification of left ventricular systolic and diastolic function; (A) Circumferential strain curves over a cardiac cycle; (B) subendocardial, mesocardial and epicardial tracings for quantification of myocardial deformation using cine-tagging. Ribeiro et al. CMR and amyloidosis Int J Cardiovasc Sci. 2019;32(2)177-189 Review Article “black-blood” imaging. This occurs because fast moving tissues, similarly to blood, whenmoving outside the slice of interest, do not produce any signal, while stable tissues or slow-moving tissues, like themyocardium, produce a high signal. However, endocardial borders (between the blood and the myocardium) are well defined. This sequence has a segmented acquisition, obtained from final expiratory apnea, synchronized with the electrocardiogram (ECG). An acceptable change, known as triple inversion recovery, is the addition of a third saturation pulse, to suppress the signal from the adipose tissue (fat saturation), which may help in the diagnosis in certain situations, such as characterization of cardiac tumors. 30,31,34 These techniques add little to the assessment of amyloidosis, and often are not included in the protocols to optimize the time of test execution. Nevertheless, in some situations, differential diagnosis is important, and situations that require evaluation of the pericardium, better tissue or even morphological characterization can be added to the basic protocol. Perfusion Myocardial perfusion imaging using CMR is obtained by the first pass of contrast (gadolinium) into ventricular cavities and then into the myocardium. One of the most frequently used methods constitutes a hybrid of fast gradient-echoandultra-fast echo- planar imagingpreceded by a saturation pulse from the tissue signal. This allows the acquisition of images in several planes every one-two heartbeats, repeatedly over a 60-second time period, along with the contrast passage. Myocardial perfusion can be used at rest or with pharmacological stress using adenosine, dipyridamole or regadenoson. The method is considered adequate to identifymyocardial ischemia and has also been widely used in the identification of cardiac tumors. Progress has been made in the velocity of data acquisition, yieldingperfusion imageswithhighspatial and temporal resolution, as well asmotion correctionmethods that positively contribute to the quality of the data. 35,39-41 In a protocol for cardiac amyloidosis investigation, this sequence will be probably unnecessary, since a suspicion of myocardial ischemia is not considered for differential diagnosis in almost all cases. Myocardial delayed enhancement Myocardial delayed enhancement is based on a T1- weighted fast gradient echo sequence, with an inversion recovery pre-pulse and inversion time (TI) adjusted