Recent Advances in Nuclear Cardiology

Abstract

Nuclear cardiology is one of the major fields of nuclear medicine practice. Myocardial perfusion studies using single-photon emission computed tomography (SPECT) have played a crucial role in the management of coronary artery diseases. Positron emission tomography (PET) has also been considered an important tool for the assessment of myocardial viability and perfusion. However, the recent development of computed tomography (CT)/magnetic resonance imaging (MRI) technologies and growing concerns about the radiation exposure of patients remain serious challenges for nuclear cardiology. In response to these challenges, remarkable achievements and improvements are currently in progress in the field of myocardial perfusion imaging regarding the applicable software and hardware. Additionally, myocardial perfusion positron emission tomography (PET) is receiving increasing attention owing to its unique capability of absolute myocardial blood flow estimation. An F-18-labeled perfusion agent for PET is under clinical trial with promising interim results. The applications of F-18 fluorodeoxyglucose (FDG) and F-18 sodium fluoride (NaF) to cardiovascular diseases have revealed details on the basic pathophysiology of ischemic heart diseases. PET/MRI seems to be particularly promising for nuclear cardiology in the future. Restrictive diseases, such as cardiac sarcoidosis and amyloidosis, are effectively evaluated using a variety of nuclear imaging tools. Considering these advances, the current challenges of nuclear cardiology will become opportunities if more collaborative efforts are devoted to this exciting field of nuclear medicine.

Keywords: Cardiology; Computed tomography; Myocardial infarction; Perfusion; Positron emission tomography; Single-photon emission computed tomography.

Fig. 1

CZT (cadmium-zinc-telluride)-based gamma cameras. a D-SPECT (Spectrum Dynamics Medical): overview, one of nine detectors, and a gantry with nine detectors from left to right. (This figure was originally published by Gambhir et al. [7]. Copyright the Society of Nuclear Medicine and Molecular Imaging). b Discovery 530c (GE Healthcare) (left), NM/CT570c (GE Healthcare) (right). (This figure was originally published by Bocher et al. [73] under the terms of the Creative Commons Attribution Noncommercial License. No change was made)

Fig. 2

The components of resolution recovery. (This figure was originally published by Ritt et al. [20] and reused with permission of Springer)

Fig. 3

F-18 flurpiridaz PET versus Tc-99m MIBI SPECT. Reversible perfusion defect in the anterior and antero-septal wall is readily seen in a patient with left anterior descending coronary artery occlusion using F-18 flurpiridaz PET but the perfusion abnormality is not clearly appreciated using Tc-99m MIBI SPECT. (Reprinted from [29] with permission of Elsevier)

Fig. 4

Three-dimensional fusion of Tc-99m MIBI perfusion SPECT and coronary CT angiography. SPECT image was generated by a dual-head gamma camera (Vertex, ADAC-Philips) and CT angiography image was obtained from in-house PACS system. The fusion process was conducted using CardIQ Fusion software package (GE)

Fig. 5

Increased F-18 FDG uptake in myocardial infarction. Delayed enhancement suggesting subendocardial infarction is shown in the basal inferior wall of MR imaging (arrows in upper panels). Increased uptake of F-18 FDG is observed in the same area (arrowheads in lower panels). (This research was originally published by Rischpler et al. [74]. Copyright the Society of Nuclear Medicine and Molecular Imaging)

Fig. 6

F-18 NaF PET for coronary atherosclerotic plaques imaging. Application of cardiac motion-frozen algorithm to PET (right) reduces noise activity and enables more prominent visualization of coronary plaques, compared to non-corrected PET (left). (This research was originally published by Rubeaux et al. [59]. Copyright the Society of Nuclear Medicine and Molecular Imaging)

Fig. 7

C-11 PiB PET for light-chain (AL) type amyloidosis. a and b Chemo-naive AL amyloidosis. c Post-therapy AL amyloidosis. d Control. (Reprinted from [72] with permission of Elsevier)