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Dive into the research topics where Chizuko Kamiya is active.

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Featured researches published by Chizuko Kamiya.


The New England Journal of Medicine | 2016

Shared Genetic Predisposition in Peripartum and Dilated Cardiomyopathies

James S. Ware; Jian Li; Erica Mazaika; Christopher Yasso; Tiffany DeSouza; Thomas P. Cappola; Emily J. Tsai; Denise Hilfiker-Kleiner; Chizuko Kamiya; Francesco Mazzarotto; Stuart A. Cook; Indrani Halder; Sanjay Prasad; Jessica Pisarcik; Karen Hanley-Yanez; R. Alharethi; Julie Damp; Eileen Hsich; Uri Elkayam; Richard Sheppard; Angela Kealey; Jeffrey D. Alexis; Gautam Ramani; Jordan Safirstein; John Boehmer; Daniel F. Pauly; Ilan S. Wittstein; Vinay Thohan; M.J. Zucker; Peter Liu

Background Peripartum cardiomyopathy shares some clinical features with idiopathic dilated cardiomyopathy, a disorder caused by mutations in more than 40 genes, including TTN, which encodes the sarcomere protein titin. Methods In 172 women with peripartum cardiomyopathy, we sequenced 43 genes with variants that have been associated with dilated cardiomyopathy. We compared the prevalence of different variant types (nonsense, frameshift, and splicing) in these women with the prevalence of such variants in persons with dilated cardiomyopathy and with population controls. Results We identified 26 distinct, rare truncating variants in eight genes among women with peripartum cardiomyopathy. The prevalence of truncating variants (26 in 172 [15%]) was significantly higher than that in a reference population of 60,706 persons (4.7%, P=1.3×10(-7)) but was similar to that in a cohort of patients with dilated cardiomyopathy (55 of 332 patients [17%], P=0.81). Two thirds of identified truncating variants were in TTN, as seen in 10% of the patients and in 1.4% of the reference population (P=2.7×10(-10)); almost all TTN variants were located in the titin A-band. Seven of the TTN truncating variants were previously reported in patients with idiopathic dilated cardiomyopathy. In a clinically well-characterized cohort of 83 women with peripartum cardiomyopathy, the presence of TTN truncating variants was significantly correlated with a lower ejection fraction at 1-year follow-up (P=0.005). Conclusions The distribution of truncating variants in a large series of women with peripartum cardiomyopathy was remarkably similar to that found in patients with idiopathic dilated cardiomyopathy. TTN truncating variants were the most prevalent genetic predisposition in each disorder.


Heart | 2007

Heterogeneity of regional systolic function detected by tissue doppler imaging is linked to impaired global left ventricular relaxation in hypertrophic cardiomyopathy

Tomoko S. Kato; Hideo Izawa; Kazuo Komamura; Akiko Noda; Hiroyuki Asano; Kohzo Nagata; S Hashimoto; N Oda; Chizuko Kamiya; Hideaki Kanzaki; Kazuhiko Hashimura; H I Ueda; Toyoaki Murohara; Masafumi Kitakaze; Mitsuhiro Yokota

Objective: To evaluate regional and global left ventricular (LV) function and LV wall thickness (LVWT) in patients with hypertrophic cardiomyopathy (HCM). Design and setting: Observational study at the National Cardiovascular Centre and Nagoya University Hospital in Japan. Participants: Thirty-six patients with HCM and 16 patients with hypertensive LV hypertrophy (LVH). Main outcome measures: Conventional echocardiography and strain rate (SR) imaging derived from tissue Doppler imaging were performed. Systolic strain (ϵsys), peak systolic SR (SRsys), peak early diastolic SR (SRdia) and LVWT were obtained from eight LV segments. LV pressure was simultaneously recorded with a high-fidelity micromanometer. Results: The regional ϵsys and SRsys were correlated with LVWT in patients with HCM (r = 0.50, p<0.001 and r = 0.63, p<0.001, respectively) but not in patients with hypertensive LVH. The standard deviations of LVWT, ϵsys and SRsys obtained from the eight LV segments of each subject were greater for patients with HCM than for patients with hypertensive LVH. The standard deviation of LVWT was correlated with those of ϵsys and SRsys (r = 0.55, p<0.001 and r = 0.56, p<0.001, respectively). The standard deviations of LVWT, ϵsys and SRsys were correlated with tau (r = 0.35, p<0.05; r = 0.47, p<0.001; and r = 0.39, p<0.005, respectively). Conclusions: Heterogeneity of regional LV systolic function detected by SR imaging is in part attributable to heterogeneity of LVH and may be linked to impaired global LV relaxation in HCM.


American Journal of Obstetrics and Gynecology | 2013

Risk factors for maternal and fetal outcome in pregnancy complicated by Ebstein anomaly

Shinji Katsuragi; Chizuko Kamiya; Kaoru Yamanaka; Reiko Neki; Takekazu Miyoshi; Naoko Iwanaga; Chinami Horiuchi; Hiroaki Tanaka; Jun Yoshimatsu; Koichiro Niwa; Tomoaki Ikeda

OBJECTIVE The goal of the study was to examine risks in pregnancy in patients with Ebstein anomaly. STUDY DESIGN Data were examined retrospectively for 13 patients (27 pregnancies, 21 live births) with Ebstein anomaly during pregnancy who were treated at our institution from 1985 to 2011. The associated anomalies in these patients were atrial septal defect (ASD) (n = 4) and the Wolff-Parkinson-White syndrome (n = 6). RESULTS Before pregnancy, 2 patients underwent ASD closure and 1 received tricuspid valve replacement (TVR). In all patients, the cardiothoracic ratio increased from 55.1 at conception to 57.0 during pregnancy and 58.0 postpartum (P < .05). Cesarean sections were performed in 3 cases: 1 with ventricular tachycardia and orthopnea (New York Heart Association [NYHA] III) preterm; at full term, and the third in a patient with a mechanical tricuspid valve who developed maternal cerebellum hemorrhage at 27 weeks. The baby died of prematurity in the third case. In all other cases (20 of 21), neonatal prognoses were good without congenital heart diseases. There were 6 spontaneous abortions. Recurrent paroxysmal supraventricular tachycardia occurred during pregnancy in 2 cases and was treated with adenosine triphosphate or verapamil. In 17 pregnancies, NYHA remained in class I and all had full-term vaginal delivery. CONCLUSION Maternal and fetal outcomes are good in patients with Ebstein anomaly and NYHA class I. However, pregnancy in Ebstein anomaly can be complicated with tachyarrhythmia or cardiac failure. In post-TVR cases, meticulous care is required for these complications during pregnancy and delivery.


Fetal Diagnosis and Therapy | 2013

Retrospective Review of Thoracoamniotic Shunting Using a Double-Basket Catheter for Fetal Chylothorax

Takekazu Miyoshi; Shinji Katsuragi; Tomoaki Ikeda; Chinami Horiuchi; Kaoru Kawasaki; Chizuko Kamiya; Yoshihito Sasaki; Kazuhiro Osato; Reiko Neki; Jun Yoshimatsu

Objective: From a single-center retrospective cohort with fetal chylothorax, we evaluated the factors related to the decision to use shunting, poor prognostic factors, and reported shunting outcomes with a new double basket-catheter device. Methods: A retrospective single-center study was performed in 35 cases of fetal chylothorax. Results: There were 35 cases of chylothorax: 23 with hydrops and 12 without hydrops. Twenty-one procedures were performed on 15 fetuses (11 with hydrops) with a single shunt in 11, two shunts in 3 and four shunts in 1. All 12 nonhydropic cases survived. In 23 hydropic cases, overall survival rates with and without thoracoamniotic shunting were 46 and 33%, respectively. The mortality rates of fetal hydropic cases with and without ascites were 93 and 11%, respectively. Fetal ascites, progression of fetal hydrops, and premature delivery at <33 weeks were significant risk factors for a poor prognosis. Progression of polyhydramnios after shunting was also associated with a poor prognosis. Obstruction of the catheter was observed in 38%. There were no direct fetal deaths associated with shunting. Conclusion: Thoracoamniotic shunting should be considered for pleural effusion before development of fetal hydrops, or at least before the appearance of fetal ascites. A double-basket catheter tends to be obstructive, but may be less invasive for fetuses.


Journal of Obstetrics and Gynaecology Research | 2014

Analysis of pregnancies in women with Takayasu arteritis: Complication of Takayasu arteritis involving obstetric or cardiovascular events

Hiroaki Tanaka; Kayo Tanaka; Chizuko Kamiya; Naoko Iwanaga; Jun Yoshimatsu

The incidence of Takayasu arteritis during child‐bearing years is relatively high. The management of pregnancies in patients with this disease is of great importance in clinical obstetrics. Here we analyzed pregnancies of women with Takayasu arteritis with and without complications.


Journal of Obstetrics and Gynaecology Research | 2015

Vaginal delivery in pregnancy with Moyamoya disease: Experience at a single institute

Shinji Katsuragi; Kayo Tanaka; Takekazu Miyoshi; Chizuko Kamiya; Naoko Iwanaga; Reiko Neki; Jun C. Takahashi; Tomoaki Ikeda; Jun Yoshimatsu

Cesarean section is commonly selected in pregnancy with Moyamoya disease. We consider vaginal delivery with epidural anesthesia a viable alternative in such cases.


Circulation | 2016

Beta-Blockers and Fetal Growth Restriction in Pregnant Women With Cardiovascular Disease

Kayo Tanaka; Hiroaki Tanaka; Chizuko Kamiya; Shinji Katsuragi; Masami Sawada; Mitsuhiro Tsuritani; Masashi Yoshida; Naoko Iwanaga; Jun Yoshimatsu; Tomoaki Ikeda

BACKGROUND The effects of β-adrenergic blockers on the fetus are not well understood. We analyzed the maternal and neonatal outcomes of β-adrenergic blocker treatment during pregnancy to identify the risk of fetal growth restriction (FGR). METHODSANDRESULTS We retrospectively reviewed 158 pregnancies in women with cardiovascular disease at a single center. Maternal and neonatal outcomes were analyzed in 3 categories: the carvedilol (α/β-adrenergic blocker; α/β group, n=13); β-adrenergic blocker (β group, n=45), and control groups (n=100). Maternal outcome was not significantly different between the groups. FGR occurred in 1 patient (7%) in the α/β group, in 12 (26%) in the β group, and in 3 (3%) in the control group; there was a significant difference between the incidence of FGR between the β group and control group (P<0.05). The β group included propranolol (n=22), metoprolol (n=12), atenolol (n=6), and bisoprolol (n=5), and the individual incidence of FGR with these medications was 36%, 17%, 33%, and 0%, respectively. CONCLUSIONS As a group, β-adrenergic blockers were significantly associated with FGR, although the incidence of FGR varied with individual β-blocker. Carvedilol, an α/β-adrenergic blocker, had no association with FGR. More controlled studies are needed to fully establish such associations. (Circ J 2016; 80: 2221-2226).


Hypertension Research | 2015

Elevated vasoinhibin derived from prolactin and cathepsin D activities in sera of patients with preeclampsia.

Ryojun Nakajima; Michiyo Ishida; Chizuko Kamiya; Jun Yoshimatsu; Mika Suzuki; Asuka Hirota; Tomoaki Ikeda; Toshio Harigaya

Elevated vasoinhibin derived from prolactin and cathepsin D activities in sera of patients with preeclampsia


Journal of Perinatology | 2012

Risk factors for maternal outcome in pregnancy complicated with dilated cardiomyopathy

Shinji Katsuragi; A Omoto; Chizuko Kamiya; Keiko Ueda; Yoshihito Sasaki; Kaoru Yamanaka; Reiko Neki; Jun Yoshimatsu; Koichiro Niwa; Tomoaki Ikeda

Objective:The goal of the study was to determine risk factors for maternal cardiac failure in pregnancy complicated with dilated cardiomyopathy (DCM).Study Design:The subjects were 29 patients diagnosed with DCM before conception or during the first 7 months of pregnancy. DCM was defined as left ventricle end-diastolic dimension (LVDd)⩾48 mm and/or fractional shortening (%FS)⩽30% on echocardiography. Patients were followed until at least 1 year after delivery and were categorized into a poor prognosis group (n=6; death or end stage heart failure of New York Heart Association (NYHA) class III and IV) and a good prognosis group (n=23; all other cases).Result:DCM was initially diagnosed during pregnancy in 6/6 and 8/23 patients in the poor and good prognosis groups, respectively (P<0.005). The %FS of the first test during pregnancy was 17.5±6.2 and 27.4±9.3% in the respective groups (P<0.005). In eight abortion cases with %FS 15.2±3.1%, %FS, cardiac function and NYHA class were maintained until 20 months after abortion. There was no relationship between LVDd and maternal outcome.Conclusion:Onset during pregnancy and decreased %FS are risk factors for a poor maternal outcome in patients with DCM. Abortion prevents further deterioration of cardiac function in patients with a very low %FS.


Journal of The American Society of Echocardiography | 2010

Traumatic Tricuspid Regurgitation Caused by Myocardial Laceration: A Three-Dimensional Echocardiographic Study

Chizuko Kamiya; Takahiro Ohara; Satoshi Nakatani; Yukiko Oe; Kazuo Niwaya; Akio Ogawa; Hideaki Kanzaki; Kazuhiko Hashimura; Masafumi Kitakaze

A 19-year-old man was admitted for severe traumatic tricuspid regurgitation (TR) 4 months after a traffic accident. Transthoracic echocardiography revealed severe TR, with an abnormal chordal structure. Three-dimensional echocardiography showed widely lacerated right ventricular endocardium involving many subvalvular components. In this case of traumatic TR, three-dimensional echocardiography was useful not only for its diagnosis but also in providing important information for surgical decision making.

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Jun Yoshimatsu

National Institutes of Health

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Tomoaki Ikeda

University of California

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Masafumi Kitakaze

Southern Medical University

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Tomoaki Ikeda

University of California

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