Toru Sakuma

Genetic association of glutathione peroxidase-1 with coronary artery calcification in type 2 diabetes: a case control study with multi-slice computed tomography

BackgroundAlthough oxidative stress by accumulation of reactive oxygen species (ROS) in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D).MethodsAn index for coronary-arteriosclerosis, coronary artery calcium score (CACS) was evaluated in 91 T2D patients using a multi-slice computed tomography. Patients were genotyped for ROS-scavenging enzymes, Glutathione peroxidase-1 (GPx-1), Catalase, Mn-SOD, Cu/Zn-SOD, as well as SNPs of NADPH oxidase as ROS-promoting elements, genes related to onset of T2D (CAPN10, ADRB3, PPAR gamma, FATP4). Age, blood pressure, BMI, HbA1c, lipid and duration of diabetes were evaluated for a multivariate regression analysis.ResultsCACS with Pro/Leu genotype of the GPx-1 gene was significantly higher than in those with Pro/Pro (744 ± 1,291 vs. 245 ± 399, respectively, p = 0.006). In addition, genotype frequency of Pro/Leu in those with CACS ≥ 1000 was significantly higher than in those with CACS < 1000 (45.5% vs. 18.8%; OR = 3.61, CI = 0.97–13.42; p = 0.045) when tested for deviation from Hardy-Weinbergs equilibrium. Multivariate regression analyses revealed that CACS significantly correlated with GPx-1 genotypes and age.ConclusionThe presence of Pro197Leu substitution of the GPx-1 gene may play a crucial role in determining genetic susceptibility to coronary-arteriosclerosis in T2D. The mechanism may be associated with a decreased ability to scavenge ROS with the variant GPx-1.

Scoring of late gadolinium enhancement in cardiac magnetic resonance imaging can predict cardiac events in patients with hypertrophic cardiomyopathy

BACKGROUND Late gadolinium enhancement (LGE) of cardiac magnetic resonance imaging (MRI) represents myocardial fibrosis and may be related to the clinical outcome of various heart diseases. This study evaluated the relationship between LGE and cardiac events in hypertrophic cardiomyopathy (HCM) using a new scoring method. METHODS AND RESULTS This study retrospectively followed 46 HCM patients without heart failure symptoms for 3.8 ± 1.8 years. Gadolinium-enhanced cardiac MRI was performed in all patients. Cardiac events including newly developed heart failure or ventricular tachyarrhythmia were evaluated during the follow-up period. We evaluated the predictive factors to identify the patients with cardiac events. None of the risk factors reported to be related to poor outcome or the existence of LGE alone could predict cardiac events, which might be due to the small number of subjects investigated in this study. A new scoring method for LGE-positive areas (LGE score) was applied and higher LGE score can predict cardiac events in this study population. CONCLUSIONS The proposed LGE score for cardiac MRI is considered to be a potentially valid method for assessing cardiac events in HCM patients.

Most patients with coronary artery calcification have no coronary artery stenosis and hyperphosphatemia should be important in reevaluating the K/DOQI guidelines.

Address correspondence and reprints requests to Dr. Keitaro Yokoyama, Division of Nephrology and Hypertension, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8471, Japan. Email: keitaro@jikei.ne.jp Dear Editor, The incidence of cardiovascular complications is very high in end-stage renal disease (ESRD) patients, and life expectancy significantly depends on the complications resulting from coronary artery stenosis. According to the K/DOQI Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease published in 2003 (1), hyperphosphatemia influences coronary artery calcification (CAC) in ESRD patients and the use of active vitamin D should be limited in patients with hyperphosphatemia. However, hyperphosphatemia is one of several factors, which effect CAC in ESRD patients. Thus we evaluated the relationship between hyperphosphatemia coronary artery stenosis as well as CAC using 16-slice multislice CT (MSCT) with CT angiography (CTA) in ESRD patients. We recruited 31 ESRD patients (18 male and 13 female, mean age 62 ± 12 years, mean duration of dialysis 6.6 ± 6.6 years) and calculated their coronary artery calcification score (CACS) according to the algorithm suggested by Agaston et al. With contrast enhancement, we evaluated their CTA based on the American Heart Association classification for coronary angiography (CAG). In the first, each coronary segment was classified as either interpretable or not interpretable according to the image quality. Second, when the patent lumen of each segment was 25% or less of the luminal diameter, it was screened for the presence of severe stenosis. As above, whether severe stenosis or occlusion was present or absent could be assessed. In 16 slice MSCT, calcified coronary lesions were found in 24 cases (80%), including 13 cases with a severe degree of calcification of CACS (more than 400). However, the serum phosphorus level was > 5.6 mg/dL in 39% of patients in this sample. With regards to the CT value of each coronary segment with contrast enhancement, severe stenosis or occlusion was found in 13% of patients. Univariate analysis suggested a relationship between serum Ca values and CACS. No statistically significant differences were seen with regard to age, dialysis duration, diabetes, serum phosphorus or serum intact-PTH. We could confirm that the calcified coronary lesions were found in 24 cases (80%), however, most of them did not have severe coronary artery stenosis or occlusion and hyperphosphatemia (serum phosphorus > 5.5 mg/dL). Hyperphosphatemia might merely be one of several factors which influence CAC in ESRD patients. Thus, we should clarify the pathophysiology of CAC in ESRD patients besides hyperphosphatemia to reevaluate the K/DOQI Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease.

Solid Tubular Carcinoma of the Breast: MR Imaging and Pathologic Correlation.

PurposeSolid tubular carcinoma of the breast is a recognizable histologic type of invasive ductal carcinoma, characterized by rare axillary lymph nodal metastases and a good prognosis. The purpose of this study is to describe the magnetic resonance (MR) characteristics of solid tubular carcinoma and to emphasize the spotty appearance on the MR subtraction images.Materials and methodsWe reviewed the MR findings of seven patients with biopsy-proven solid tubular carcinoma. Two of the 7 cases were of the pure type (more than 85% solid tubular component) and the remaining 5 were of the mixed type (50% to 85% solid tubular component). The mean age of the patients was 56 years.ResultsThe mean size of the lesions was 28 mm. On Tl-weighted images four of the lesions were visible and three were not identified. After Gd-DTPA all the lesions were enhanced. On the subtracion images, “popcorn” appearence areas were noted in the stained mass.ConclusionOur preliminary results suggest that solid tubular carcinomas have a characteristic apperarence on the subtraction MR images.

Evaluation of epicardial adipose tissue volume and coronary artery calcification in Japanese patients with psoriasis vulgaris

Epicardial adipose tissue (EAT) is implicated in the development of coronary atherosclerosis by secretion of inflammatory adipocytokines. Recent studies have shown significantly higher EAT volume in psoriatic patients compared with that in control subjects, but this has not been validated in Japanese patients. We enrolled 86 Japanese patients with moderate to severe psoriasis vulgaris and 31 control subjects, and evaluated EAT volume and coronary artery calcification (CAC) by retrospectively assessing non‐enhanced computed tomography obtained through routine examinations. Both mean EAT volume and mean CAC score were not significantly different between the two groups. Interestingly, however, a subanalysis with those of 50 years of age or less (28 psoriatic patients and seven non‐psoriatic subjects) showed significantly higher mean EAT volume in psoriatic patients. Similarly, the ratio of the presence of at least one CAC was significantly higher in this group. Our findings suggest that Japanese psoriatic patients should also be aware of the cardiovascular risk, and EAT volume and CAC may be useful tools to predict such risk.

Contrast-enhanced magnetic resonance imaging to detect chronic aortic dissection complicated by acute aortitis

When chronic aortic dissection (CAD) is associated with aortic dilatation, the risk of aortic rupture increases. We report a case of CAD complicated by acute aortitis that was depicted in contrast-enhanced magnetic resonance imaging (MRI). Contrast-enhanced MRI allows early detection of subtle changes in the aortic wall as well as disease activity. Inflammation of aortic wall in the aortic dissection can be at higher risk of the dissected aortic expansion and rupture. When we recognize inflammation of unknown origin with CAD, contrast-enhanced MRI should be performed to rule out CAD complicated by acute aortitis may lead to catastrophic complications.

Fluctuant tonus of the coronary arteries possibly documented by repeated multidetector row computed tomography

License. The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Permissions beyond the scope of the License are administered by Dove Medical Press Limited. Information on how to request permission may be found at: http://www.dovepress.com/permissions.php Research Reports in Clinical Cardiology 2014:5 327–337 Research Reports in Clinical Cardiology Dovepress

Multidetector-Row CT for Assessment of Kawasaki Disease

Kawasaki disease is an acute febrile illness, causing mucosal inflammation, skin rash, and cervical lymphadenopathy, recognized most often in children younger than 4 yr of age. It was first described by Dr. Tomisaku Kawasaki in Japanese literature in 1967 (1), and then in English in 1974 (2). The disease is of unknown etiology that produces a systemic vasculitis, which is most severe in the medium-sized arteries, and especially prominent in the coronary arteries. This can be associated with considerable morbidity and mortality, mostly the result of myocardial involvement and coronary artery complications such as aneurysm, calcification, and stenosis. In Japan as well as in North America, Kawasaki disease is presently a leading cause of acquired heart disease in children (3).