Accumulating evidence revealed that adipose tissues secrete pro-inflammatory and anti-inflammatory humoral factors, called as adipocytokines. Most of the arteries are surrounded by perivascular adipose tissue (PVAT), which influences adjacent artery by secreting adipocytokines. PVATs are supposed to be athero-protective under healthy conditions, whereas PVATs are athero-promoting in obesity. Recent clinical studies suggested that coronary atherosclerosis is associated with increased volume of epicardial adipose tissue (EAT), PVAT of coronary artery. It was suggested that enhanced inflammation in EAT is also associated with vasospastic angina. In this review article, we will summarize recent findings about potential roles of EAT in the pathogenesis of coronary atherosclerosis.

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Purpose: “Heart Function View (HFV)” is a software that performs phase analysis as well as functional assessment of the left ventricle (LV) using myocardial perfusion single photon emission computed tomography (SPECT) (MPS). Phase analysis-derived phase standard deviation (PhSD) and histogram bandwidth (PhHB) are good indices for detecting LV dyssyncrony. We aimed to examine whether PhHB and/or PhSD (PhHB/PhSD) are useful clinical indicators that reflect the severity of heart failure (HF) in comparison with the LV ejection fraction (EF).
Methods: Patients underwent ^99mTc-tetrofosmin quantitative gated MPS including treadmill exercise. In HFV analyses, patients with induced ischemia were excluded. Phase and time-volume curve analyses were performed using HFV (n=66).
Results: PhHB/PhSD correlated with LV end-diastolic volume (EDV), end-systolic volume (ESV), the first-third filling fraction (1/3FF), and peak filling rate (PFR) as well as echocardiography tissue Doppler-derived E/e’ as hemodynamic parameters of HF severity. LVEF also correlated with these hemodynamic parameters, except for 1/3FF. PhHB/PhSD positively correlated with log BNP as a neurohumoral marker of HF severity. LVEF negatively correlated with log BNP. PhHB/PhSD negatively correlated with exercise capacity as physiological indicators of HF severity, whereas LVEF did not. PhHB/PhSD were significantly greater in patients receiving cardiac resynchronization therapy (CRT, n=6) than in non-CRT patients (n=66), whereas LVEF were lower.
Conclusion: PhHB/PhSD, similar to LVEF, are useful clinical indicators for evaluating HF severity. However, the clinical significance of LVEF and PhHB/PhSD differ. Thus, a phase analysis may additively offer useful information for the management of HF.

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Background: Various imaging modalities are used to identify and characterize cardiac masses. While echocardiography remains the preferred imaging modality to evaluate cardiac masses, computed tomography (CT), magnetic resonance imaging (MRI), and ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT are being increasingly employed to assess cardiac mass lesions. However, the clinical value of non-invasive cardiac imaging for differentiating between primary cardiac mass and metastatic lesions has not yet been examined in detail. The purpose of the present study was to evaluate the diagnostic utility of non-invasive cardiac imaging for differentiating primary cardiac tumors from metastatic lesions, and non-tumorous lesions.
Methods: A retrospective review was conducted on 22 cardiac mass lesions in 20 patients assessed by cardiac imaging (at least one of CT, MRI, or ¹⁸F-FDG PET/CT) between December 2005 and March 2017. CT findings included the tumor size, location, existence of calcification, and morphology of the base portion of the lesion. MRI parameters included signals with T1-weighted imaging (T1WI), T2WI, mobility with cine imaging, and contrast enhancement. Tracer uptake by each cardiac lesion using ¹⁸F-FDG PET/CT was also evaluated.
Results: Among 17 cardiac mass lesions assessed by contrast-enhanced CT, all cardiac myxomas and papillary fibroelastomas had a pedunculated base portion. All metastases located in the cavity had a sessile base portion (P=0.0035). Malignant tumors (metastases and malignant lymphoma) had no mobility, while cardiac myxomas had a slightly higher frequency of mobility with cine MRI (0% vs. 100%, P=0.0667). Among the four lesions for which ¹⁸F-FDG PET/CT was performed, the three malignant lesions had strong ¹⁸F-FDG uptake, while the benign lesion showed insignificant accumulation.
Conclusions: The characteristics of the base portion of cardiac mass were useful for differentiating primary cardiac tumors from metastatic cardiac tumors. Cine MRI also exhibited diagnostic utility for differentiating between primary cardiac tumors and metastases. Therefore, non-invasive cardiac imaging may be employed to differentiate cardiac mass lesions. The accurate diagnosis of cardiac mass lesions may require the assessment of multiple characteristics on images.

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Background: Phase analysis of left ventricular contraction has incremental value for facilitating the diagnosis of cardiovascular disease using electrocardiography-gated myocardial perfusion imaging (MPI). However, it is unclear whether phase analysis aids the diagnosis of ischemic heart disease using technetium-99m (^99mTc)-labeled perfusion agents under pharmacological stress. As pharmacological stress does not usually induce “true” ischemia, and ^99mTc MPI is generally performed about one hour after the initiation of stress testing, it is questionable whether phase deterioration can be measured in such conditions.
Methods: We retrospectively analyzed the cases of 61 consecutive patients who underwent adenosine stress/rest MPI using ^99mTc-labeled perfusion agents. Phase parameters [bandwidth, phase standard deviation (PhaseSD), and entropy] were evaluated using automatic analysis software (cardioREPO). All parameters were assessed both under stress and at rest. The changes (delta) in the phase parameters between the stress and resting conditions were also measured.
Results: The patients were separated into those without and with ischemia. Stress bandwidth (46.2±13.0 vs 73.2±41.2, respectively), stress PhaseSD (11.7±3.2 vs 18.2±10.5), stress entropy (0.46±0.06 vs 0.53±0.12), rest PhaseSD (9.4±3.0 vs 12.5±6.4) and rest entropy (0.42±0.07 vs 0.46±0.10) and the delta bandwidth (6.49±11.88 vs 23.58±28.04) and delta PhaseSD (2.29±3.11 vs 5.78±6.89) values exhibited significant differences between the two groups although there were large overlaps between the two groups.
Conclusions: On ^99mTc MPI performed under pharmacological stress, some minor left ventricular contraction phase changes were observed.

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The Japanese Ministry of Health, Labour and Welfare (JMHLW) approved ¹³N-ammonia (¹³N-NH₃) for detecting coronary artery disease (CAD) and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) for cardiac sarcoidosis in 2012. These 2012 PET approvals shifted cardiac PET from research PET to clinical PET in Japan. Since the 2012 approvals, the nuclear cardiology community has realized the challenges of applying ¹³N-NH₃ PET in clinical practice given the limited reimbursement through the health insurance system. Similar to the case with cardiac sarcoidosis, Japanese cardiologists have put great effort into treating patients with great arteritis such as Takayasu arteritis and have also shown the diagnostic utility of ¹⁸F-FDG PET/CT. Considering these issues, the Japanese Society of Nuclear Medicine (JSNM) and Japanese Circulation Society (JCS) worked together with JMHLW to update health insurance policy regarding PET. In addition, physiology-based coronary intervention has played an important role in the management of patients with CAD. Based on these recent developments and discussions with major societies, JMHLW released its updated reimbursement policy on March 5, 2018. This rapid communication will address the key issues of this policy update related to cardiovascular PET and coronary intervention.

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In April 2018, the use of F-18 fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) for large-vessel vasculitis (LVV) was finally approved under the Japanese national health insurance system. The use of ¹⁸F-FDG PET in LVV differs from the oncological use in several aspects such as the patients’ age distribution, precautions regarding the tracer dosage, and the utility for diagnosis and patient management. Considering the higher incidence of Takayasu arteritis in Japan than in western countries, it is expected that young females will undergo ¹⁸F-FDG PET for LVV for the diagnosis and the management. The Japanese Society of Nuclear Cardiology (JSNC) has issued this brief statement about the use of ¹⁸F-FDG PET for diagnosing/managing LVV, which focuses on the specific characteristics of LVV, imaging protocols, the clinical utility of ¹⁸F-FDG PET, and some issues that clinicians should be aware of.

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Cardiovascular device-related infections include infections occurring at heart valve prosthesis, cardiovascular implantable electronic devices, left ventricular assist device catheters and vascular graft. Complications, including infections associated with implanted medical devices have been increased. The diagnosis of cardiovascular device-related infections is challenging since symptoms and signs are often inconclusive and clinical presentations may be extremely heterogeneous. Imaging using the “3M” approach (i.e., multimodality, multi-tracers and multisciplinary) has been integrated into the traditional diagnostic criteria to fill such uncertainty gap with information on the biochemical burden of these infections. The present review aimed to provide an overview of the main applications and results of nuclear cardiology imaging in cardiovascular device-related infections.

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Regadenoson is an increasingly used pharmacological stress agent for myocardial perfusion imaging (MPI) that has an important advantage over other primary coronary vasodilators. Both adenosine and dipyridamole have a non-selective action on the adenosine receptors and can therefore induce bronchospasm in susceptible individuals. In contrast, regadenoson acts selectively on the adenosine receptor subtype responsible for the coronary vasodilator effect of these agents with little, if any, activity on adenosine receptor-mediated bronchoconstrictive pathways. This gives regadenoson an advantage over other vasodilators in the management of patients with obstructive airways disease undergoing stress MPI. There is compelling evidence for the improved tolerability of regadenoson stress in patients with a history of bronchial hyperreactivity. Moreover, regadenoson has proved to be safe in advanced forms of lung disease and is currently the preferred stress agent in these patients. Experience on the use of regadenoson in poorly controlled asthma or chronic obstructive pulmonary disease (COPD) is limited, and thus caution must be exercised when considering regadenoson stress in patients with suspected persistent or clinically manifest airway obstruction.

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Kinetic modeling is gaining clinical relevance with wider adoption of myocardial blood flow quantification with PET. This work introduces the reader to the basic concepts of dynamic imaging, the one-tissue kinetic model, and tracer extraction correction. Key tracer specific nuances of kinetic modeling are highlighted. Finally, possible pitfalls which must be considered for accurate myocardial blood flow quantification are discussed.

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The debate on the role of anatomy and function in the assessment of coronary artery disease has been progressing for decades. While each imaging modality brings its own strengths and weaknesses, a multimodality image fusion approach combining an anatomical acquisition with a functional one has the potential of providing all the complementary information necessary to select the proper treatment. The technology has been available to physicians for a decade, but the recent introduction of positron emission tomography-derived absolute myocardial blood flow has further advanced the case for an image fusion diagnostic approach.

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In recent years, the application of artificial intelligence (AI) to medical images has advanced rapidly. Especially since the learning method called deep learning has spread, we have made remarkable progress including precision. It is application ranges from detection of abnormal lesion on the image to screening assistants or selection of drugs necessary for treatment.
Study of nuclear medicine is progressing with AI, and reports are also made on bone scintigraphy and PET images. In nuclear cardiology, software for detecting abnormal lesion of myocardium using artificial neural network (ANN) by machine learning and making it useful for image interpretation aid has been developed. In the future, it is expected that study and development will also advance interpretation assistance by deep learning and abnormal lesion detection. However, for deep learning, the number of images required for study becomes enormous and it is a point of discussion.

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Decisions related to differences of the measures of central tendency of population parameters are an important part of clinical research. Choice of the appropriate statistical test is critical to avoiding errors when making those decisions. All statistical tests require that one or more assumptions be met. The t-test is one of the most widely used tools but is not appropriate when assumptions such as normality are not met, especially when small samples, <40, are used. Non-parametric tests, such as the Wilcoxon rank sum and others, offer effective alternatives when there are questions about meeting assumptions. When normality is in question, the Wilcoxon non-parametric tests offer substantially higher levels of power and an reliable alternative to the t-test.

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The Japanese Ministry of Health, Labour and Welfare (JMHLW) introduced the Clinical Research Law¹ in April 2018. Clinical studies to evaluate pharmacokinetics or the efficacy or safety of in vivo diagnostic radiopharmaceuticals have to be conducted under either the Clinical Research Law or the Japanese Good Clinical Practice (GCP) guidelines. The Clinical Research Law provides stricter regulation than does the current Ethical Guideline for clinical studies, and it allows the regulatory authority to issue orders to suspend or change clinical studies. Given that a clinical study may require the same amount of time, human resources and funding resources no matter which regulatory scheme is followed, clinical investigators need to bear in mind the objectives and funding support for the planned study when choosing which legislation to adhere to. This article reviews various factors that may help determine which of the recently introduced pieces of legislation is applicable in the planning of a particular clinical study. We also aim to establish approaches to identify the appropriate law and to enable non-clinical studies to move forward to the clinical study phase.

¹This review article was written before official release of the English translation of the Clinical Research Law in June 28 2018. Although the law is officially entitled the Clinical Trials Act in English, this review uses the terminology “the Clinical Research Law”.

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Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare and intractable disease, first reported in Japanese patients with congestive heart failure (HF) requiring heart transplant. TGCV is characterized by the excessive accumulation of triglyceride (TG) in cardiomyocytes and vascular smooth muscle cells, which leads to coronary artery disease, HF, and arrhythmia. In TGCV, long-chain fatty acid (LCFA), a major energy source for the normal heart, accumulates as TG in cytoplasmic lipid droplets. In 2009, we launched the Japan TGCV study group to elucidate the pathophysiology of TGCV and have developed diagnostic procedures along with specific treatment. Single-photon emission computed tomography (SPECT) with iodine-123-β-methyl iodophenyl-pentadecanoic acid (BMIPP), a radioactive analogue for LCFA, is a useful diagnostic tool to detect impaired myocardial LCFA metabolism in TGCV. Since we posted the latest version of diagnostic criteria including the myocardial washout rate of BMIPP in SPECT in 2016, we have identified 138 patients with TGCV, 27 of whom have died. More recently, we developed a TGCV severity score consisting of specific questionnaires in order to assess symptoms and activities of daily living in patients with TGCV.

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Takotsubo syndrome (TTS) was first described in 1990. A wide variety of TTS cases have been reported since then; the international consensus has proposed several diagnostic criteria. The current diagnostic system often relies on identifying combinations of subsets of symptoms, or criteria, to define diagnoses. In the recently proposed TTS diagnostic criteria, obstructive coronary syndrome and pheochromocytoma involvement changes. Here, we review the criteria and the role of nuclear imaging in TTS diagnosis and discuss new directions that can provide better information.

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Takotsubo syndrome is an acute clinical condition mimicking acute myocardial infarction. Nuclear cardiology imaging obtains information that is close to the pathology of Takotsubo syndrome and is widely used in clinical practice to accumulate evidence. Regional semi-quantitative analysis revealed that the metabolic abnormalities were exclusively in the apical area, which was one of the features of Takotsubo syndrome. ¹²³I-MIBG has the ability to reveal apical sympathetic nerve abnormalities, which often are prolonged. This article describes both the latest findings of Takotsubo syndrome as well as the characteristics of the disease condition and the practical use of a nuclear cardiology technique.

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Cardiac sarcoidosis has long been an ambiguous diagnosis and tended to be misdiagnosed because of the low sensitivity of endomyocardial biopsy. In addition, cardiac sarcoidosis sometimes mimics other diseases, such as dilated cardiomyopathy and myocardial infarction with aneurysm. Recent advancements in imaging make it possible to detect it earlier, differentiate from other diseases, and monitor the treatments. New guidelines for cardiac sarcoidosis appreciate imaging and include isolated cardiac sarcoidosis. Therefore, detection rate has been increasing after introduction of the new guidelines. However, problems still remain, such as optimal doses of steroids, alternative therapy to steroids, and complicated diagnostic criterion. This review focuses on the remaining problems to be solved regarding cardiac sarcoidosis management.

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Heart Failure (HF) is a life-threatening disease which incidence is growing over the years, leading to a considerable increase in disability, mortality and healthcare costs. The actual treatment of HF, includes, beside optimal medical treatment, use of resynchronization therapy and implantable cardiac defibrillator. In some developing countries, the cost of these two devices is extremely high, being mandatory the adequate selection of the patients whose will benefit more from these measures. ¹²³I-MIBG scintigraphy is the only technique approved to provide information of the adrenergic function of the heart, being a powerful risk stratification tool in patients with HF. Multiple studies have shown that the evaluation of cardiac sympathetic nerve activity using ¹²³I-MIBG imaging, especially the heart-to-mediastinum ratio, can differentiate high-risk from low-risk patients. Cardiac MIBG imaging has still poor availability in Latin America. It is mostly performed in Brazil, where some studies showed the possible benefits and potential uses for MIBG.

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Nuclear cardiology studies have been part of nuclear medicine practice from 1970s in Korea. It showed a steep growth in 1990s when single-photon emission computed tomography (SPECT) with advanced software was introduced, and it is still growing. SPECT myocardial perfusion imaging takes 12.8% of total gamma imaging studies in 2016. Although ²⁰¹Tl is still preferred to ^99mTc for myocardial perfusion tracer there is a trend of growing use of ^99mTc perfusion agents. While, the use of cardiac positron emission tomography (PET) is still very limited, which takes less than 1% of total PET studies. The reimbursement for cardiac PET includes only ¹⁸F FDG imaging for myocardial viability assessment in patients with acute myocardial infarction before and after revascularization. Cardiac FDG PET studies for sarcoidosis, amyloidosis, myocarditis, and vasculitis are reimbursed in only limited cases. ¹³N ammonia is the only PET myocardial perfusion tracer that is approved by the Korean Food and Drug Administration. A multi-disciplinary group, the Korean study group of cardiovascular imaging (KCI), is trying to establish new guidelines which include the most up-to-date information on cardiac imaging modalities in various clinical scenarios.

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J-ACCESS was the first database created in Japan to assess prognosis of patients with coronary artery disease (CAD) using myocardial perfusion imaging and its quantitation. Four J-ACCESS studies have been completed since 2001, and 4,629 patients who were diagnosed with or suspected of having CAD were registered in the initial study. The J-ACCESS investigations of prognostic databases after stress myocardial perfusion single-photon emission computed tomography (SPECT) between 2004 and 2018, which included patients with diabetes mellitus (J-ACCESS 2), chronic kidney disease (J-ACCESS 3) and coronary revascularization (J-ACCESS 4), uncovered novel findings. Myocardial perfusion defects and left ventricular function were identified as determinants of major cardiac events, and the clinical variables of diabetes and chronic kidney disease (or estimated glomerular filtration rate) were selected as independent predictors of cardiac events. Multivariable risk models can estimate major event risk, and thus stratify patients according to the likelihood of being at low, intermediate, or high risk for CAD.

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Optical coherence tomography (OCT) has emerged as a high-resolution (10-20μm), light-based, intravascular imaging technique capable of investigating detailed coronary plaque morphology. OCT is highly sensitive and specific for characterizing fibrous, fibrocalcific, and lipid-rich plaque. OCT is capable of discriminating 3 types of unstable plaque morphologies underlying coronary thrombosis such as plaque rupture, erosion, and calcified nodules. The high resolution of OCT has a potential to identify important features of vulnerable plaques such as thin-cap (<65μm thick) fibroatheroma, macrophages, vasa vasorums, cholesterol crystals, and micro-calcifications. As compared with conventional intravascular ultrasound, OCT provides more accurate measurements of coronary lumen diameter and lesion length, which is useful in determining stent size. OCT is much more sensitive in detecting inadequate stent findings such as intrastent tissue protrusion, incomplete stent apposition, stent edge dissection, and intrastent thrombus, which is helpful in optimizing stent implantation. Recently developed new stent optimization software such as OCT/angiography co-registration and 3-dimentional view enhances ease of use, simplifies interpretation and allows us to literally visualize a better outcome of percutaneous coronary intervention (PCI). In conclusion, OCT is a promising technology to assess coronary atherosclerosis and to guide PCI.

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Coronary computed tomography angiography (CCTA) is the most commonly used modality for noninvasive plaque imaging in clinical settings. Characteristics of rupture-prone vulnerable plaques include positive remodeling, low attenuation, and napkin-ring sign in CCTA. About 60% of all vulnerable plaques have these characteristics, and these coronary lesions often result in plaque rupture. Identification of such groupings of coronary artery characteristics has been used to predict cardiovascular events.

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This brief review intends to highlight how heterogeneous the world is regarding cardiovascular mortality and overall use of nuclear cardiology, especially in the developing world where mortality remains high. This was one of the important topics discussed during ASNC2017 in Kansas City, USA. Despite the challenges appropriate use of nuclear cardiology could be helpful to estimate risk and guide patient management bringing opportunities to the developing world. In addition we briefly list key issues which could serve as a guide to foster the development of nuclear cardiology, including the imperative need to avoid unnecessary revascularizations which might be even more challenging with increased use of non-invasive diagnosis of disease by computed tomography.

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The indications and methods for and volumes of nuclear cardiology procedures differ among countries, and each country has specific nuclear cardiology characteristics. Nuclear cardiology practice in Japan has the following specific characteristics: 1) stress myocardial perfusion imaging is severely underused; 2) thallium-201 (²⁰¹Tl) is frequently used for perfusion imaging, which might increase the public radiation burden; 3) iodine-123-labeled beta-methyl-iodophenyl pentadecanoic acid (¹²³I-BMIPP) is readily available for cardiac imaging, which has resulted in large amounts of evidence about the utility of this technique being collected in Japan; and 4) ¹²³I-meta-iodobenzylguanidine (MIBG)-based imaging is readily available for examining cardiac and neurological disease, especially Parkinson’s disease. In some respects, Japan is behind the global standard and must follow the lead of other countries (issues 1 and 2). However, in other areas Japanese nuclear cardiologists can pave the way for other countries (issues 3 and 4). These issues were presented and discussed at the annual meeting of the American Society of Nuclear Cardiology in 2017.

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Shipments of radioactive sources to Nuclear Cardiology facilities must be handled properly to avoid unintended radioactive contamination. Appropriate personnel must be involved in the ordering, receiving, surveying, and opening of radioactive shipments, and must record relevant information for each package. Action limits defining radioactive contamination include a wipe test result indicating removable activity from the exterior of a package exceeding 185 Bq (0.005 μCi) above background radiation levels for a surveyed area of 100 cm², or exposure meter readings exceeding 0.1 mSv/hr (10 mrem/hr) 1 meter from a package, or exposure rate readings at the package surface exceeding 2 mSv/hr (200 mrem/hr). Following standardized procedures will ensure personnel of Nuclear Cardiology facilities that shipments of radioactivity are handled properly and safely.

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Since cardiac sarcoidosis (CS) portends adverse outcomes, early diagnosis of active inflammation in CS is essential for therapeutic and prognostic advantages. ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) has been used for the clinical evaluation of active inflammatory lesions in CS. While myocardium can utilize both free fatty acids and glucose as the substrates of energy metabolism, the physiological myocardial ¹⁸F-FDG uptake often makes it difficult to detect the pathological ¹⁸F-FDG accumulation. Prolonged fasting and low-carbohydrate diet are most commonly used for suppressing physiological myocardial ¹⁸F-FDG uptake, and moreover unfractionated heparin administration is sometimes considered. Sufficient preparation allows for the establishment of increased ¹⁸F-FDG uptake in myocardium as active inflammatory lesions. Typical patterns of pathological ¹⁸F-FDG accumulation in myocardium are “focal” and “focal-on-diffuse” and these are often corresponded with myocardial perfusion abnormality. In case with inconclusive ¹⁸F-FDG uptake, the simultaneous interpretation with myocardial perfusion imaging is useful and helpful to evaluate clinically significant ¹⁸F-FDG uptake in CS.

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Nuclear imaging of the failing myocardium is targeting the impaired part related to several processes of myocardial metabolism or work. Myocardium mainly utilizes fatty acid or glucose for ATP production in mitochondria. Intracellular calcium handling, which needs an amount of ATPs, induces myocardial contraction and relaxation, and is regulated with beta adrenal-stimulation. In the failing myocardium, any of these parts related to the myocardial work are variedly impaired, and could be the imaging target. Despite recent advancement of heart failure treatment, the patients with heart failure remain in high morbidity and mortality. For appropriate managements or prediction of prognosis in patients with heart failure, it is important to evaluate the mechanism of the failing myocardium. In this article, we focus on the usefulness of the 2 radionuclide imaging in evaluating sympathetic nerve function using myocardial ¹²³I-MIBG scintigraphy and mitochondrial function using myocardial ^99mTc-sestamibi SPECT in the patients with cardiomyopathy.

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Nuclear cardiology is useful for risk stratification of major cardiac events (MCEs) in Japanese patients with coronary artery disease (CAD). Results of the J-ACCESS study demonstrated that the severity of the summed stress score (SSS) stratifies the risk of future MCEs. A normal SSS predicts a good prognosis and a higher SSS indicates a higher MCE risk. Investigating the association between therapeutic strategy and the risk of MCEs, we demonstrated that revascularization reduces the risk of MCEs in patients with >10% ischemia while optimal medical therapy achieves the same outcome in patients with ≤5% ischemia. We also formulated a risk equation on the basis of evidence obtained from nuclear cardiology to predict the risk of MCEs excluding severe heart failure. In order to benefit from such evidence, it is necessary that expert interpreters precisely evaluate ischemia based on images derived during nuclear cardiology studies. However, automated quantification with total perfusion deficit does not require expert interpreters. We have reported the usefulness of automated quantification with the total perfusion deficit derived from a Japanese normal database in Japanese patients with CAD. Ischemic data obtained from nuclear cardiology are extremely useful for predicting MCEs in patients with CAD. A therapeutic strategy guided by the ischemic data facilitates good medical management with an associated improved prognosis.

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The Japanese Society of Nuclear Cardiology (JSNC) has given out its Technical Award for outstanding technologists since 2012 to promote nuclear cardiology research. Mieko Ota, RT, MHSc won the 6th JSNC Technical Award. The issue of “Shinzo Kaku Igaku” (Japanese Journal of Nuclear Cardiology) contains her original award-winning article. She and her colleagues aimed to assess the differences between ¹²³I-metaiodobenzylguanidine (MIBG)-SPECT scan accumulation patterns and ^99mTc-sestamibi (MIBI)-SPECT scan images with phase analysis observed in pediatric patients with congenital heart disease (CHD). Her results showed that decreased cardiac MIBG uptake reflected sympathetic denervation secondary to CHD operative procedures in patients with CHD who exhibited a mismatch in uptake between the MIBG and MIBI. In cases with normal perfusion and abnormal MIBG, it was shown that her group should consider the possibility of underlying CHD and its associated procedures in adult CHD patients.

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