Publications by authors named "Naotsugu Oyama"

Background: Repeated hospitalization is a predictor of outcomes in heart failure, indicating the presence of symptoms, a deteriorated condition at pre-admission, and worsened prognosis.

Objectives: The current database study aimed to understand the clinical and economic burden of repeated hospitalizations among patients with heart failure in Japan. The effect of repeated hospitalizations on the subsequent in-hospital mortality was the primary objective; economic burden of heart failure after discharge was investigated as a secondary outcome.

View Article and Find Full Text PDF

We investigated the impact of heart failure (HF) on daily life and satisfaction with current HF medication from the patient perspective in a real-world study in Japan. A cross-sectional survey of 154 HF patients treated by 58 cardiologists was conducted in Japan using patient self-completed questionnaires about their daily life and satisfaction with HF medication, as well as patient record forms completed by their physicians capturing corresponding data. The mean age of patients was 72.

View Article and Find Full Text PDF

The aim of this cross-sectional survey was to characterize the role of and burden on caregivers of heart failure (HF) patients in Japan, since such data are limited at present. Data from 126 caregivers whose average age was 63.5 years were analyzed.

View Article and Find Full Text PDF

Background: Our objective was to characterize cases of hospitalized heart failure (HHF) focusing on in-hospital resource utilization (particularly furosemide doses) and worsening heart failure (WHF), and identify which factors are associated with the length of stay (LOS).

Methods: Cases of HHF (≥20 years), excluding those undergoing surgical procedures and in-hospital deaths, were retrieved from the Japanese Diagnosis Procedure Combination database (April 2012 to March 2016). WHF was defined using eight components, including up-titration of intravenous drugs and non-pharmacological management.

View Article and Find Full Text PDF

: The dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin is indicated for type 2 diabetes mellitus (T2DM). However, the long-term safety, effectiveness, and clinical relationship with cardiovascular events of vildagliptin have not been evaluated in Japan.: The authors conducted post-marketing surveillance (PMS) to evaluate the safety and effectiveness of vildagliptin in more than 3000 Japanese T2DM patients for up to 3 years.

View Article and Find Full Text PDF

: Vildagliptin is a dipeptidyl peptidase-4 inhibitor that reduces glycemia in patients with type 2 diabetes mellitus (T2DM). When approved in 2013, data on vildagliptin combined with >750 mg/day metformin in Japanese patients were limited. There is a need to confirm the safety and efficacy of vildagliptin in combination with oral antidiabetic drugs (OADs).

View Article and Find Full Text PDF

Background: Vildagliptin is indicated for type 2 diabetes mellitus (T2DM); however, the onset and exacerbation of diabetic complications in Japanese T2DM patients treated with vildagliptin is unknown.

Research Design And Methods: This 2-year post-marketing surveillance (PMS) assessed the real-world safety and efficacy of vildagliptin therapy in 19,218 Japanese T2DM patients. The relationship between the incidence of macro- and microvascular complications with patient characteristics and changes in glycemic control (HbA1c) were evaluated.

View Article and Find Full Text PDF

Background: The purpose of this study was to investigate the levels of asthma control in Japanese adult patients in general practice.

Methods: 11490 Japanese patients with adult asthma who were treated by primary care physicians were enrolled. The treatment steps and levels of asthma control were determined according to the Japanese Asthma Prevention and Management Guideline 2009.

View Article and Find Full Text PDF

Background: Notch1 regulates binary cell fate determination and is critical for angiogenesis and cardiovascular development. However, the pathophysiological role of Notch1 in the postnatal period is not known. We hypothesize that Notch1 signaling in vascular smooth muscle cells (SMCs) may contribute to neointimal formation after vascular injury.

View Article and Find Full Text PDF

Rho kinases (ROCKs) are serine-threonine protein kinases that regulate the actin cytoskeleton. Recent studies suggest that ROCKs also play an important role in cardiovascular disease. However, the isoform- and tissue-specific role of ROCKs in mediating this process is unknown.

View Article and Find Full Text PDF

Although Rho-associated kinase (ROCK) activity has been implicated in cardiovascular diseases, the tissue- and isoform-specific roles of ROCKs in the vascular response to injury are not known. To address the role of ROCKs in this process, we generated haploinsufficient Rock1 (Rock1(+/-)) and Rock2 (Rock2(+/-)) mice and performed carotid artery ligations. Following this intervention, we found reduced neointima formation in Rock1(+/-) mice compared with that of WT or Rock2(+/-) mice.

View Article and Find Full Text PDF

Mechanical stress by pressure overload due to hypertension or valvular heart disease such as aortic valve stenosis induces cardiac hypertrophy. It has been well established that the mechanical stretch of cardiac myocytes in vitro induces hypertrophic responses such as the expression of immediate early response genes including c-fos. However, it remains uncertain whether the mechanical forces due to pure atmospheric pressure can induce similar responses in cardiac myocytes.

View Article and Find Full Text PDF

A 49-year-old man with poorly controlled diabetes was admitted to Kushiro Rosai Hospital, Hokkaido, Japan after scalding both feet with boiling water. Because of poor healing, he was assessed for peripheral arterial disease. Angiography revealed total occlusion of the right common and external iliac arteries, diffuse stenosis of the right superficial femoral artery, focal stenosis of the left common iliac artery and chronic total occlusion of the left superficial femoral artery.

View Article and Find Full Text PDF

A 37 year-old female who had suffered from arteritis for 20 years underwent a Bentall operation. Since severe stenosis was observed in her left main coronary artery (LMCA) the following year, a minimally invasive direct coronary artery bypass (MIDCAB) operation was performed. Unfortunately, she again complained of angina about 6 months after the second surgery and coronary angiography (CAG) revealed that her left internal thoracic artery graft was totally occluded.

View Article and Find Full Text PDF

Acute myocardial infarction (AMI) has gradually been increasing in Japan; however, since the burden of Japanese residents for risk factors (RFs) of AMI, such as hypercholesterolemia, is chronologically less accumulated compared with American and European people, their RFs of AMI may be different from those in western countries. To answer this question, a retrospective community-based study was carried out enrolling 722 first time AMI patients in Hokkaido, the northern island of Japan. As controls, 1748 age-, sex- and residence-matched subjects were randomly chosen from a data-base of a health check-up organization.

View Article and Find Full Text PDF

Background: There are few biological markers, which strictly show the severity of congestive heart failure (CHF).

Methods And Results: Lymphocyte G-protein coupled receptor kinase (GRK) mRNA expression was measured by quantitative reverse transcription-polymerase chain reaction in 15 CHF patients: 5 patients classified as New York Heart Association class-II treated with angiotensin converting enzyme inhibitor (ACEI) (IIA), 5 patients in class-II without ACEI (IIC), and 5 patients in class-III treated with ACEI (IIIA). GRK mRNA level in IIIA was significantly higher than those in IIA (p<0.

View Article and Find Full Text PDF

Rho-associated kinases (ROCKs), the immediate downstream targets of RhoA, are ubiquitously expressed serine-threonine protein kinases that are involved in diverse cellular functions, including smooth muscle contraction, actin cytoskeleton organization, cell adhesion and motility, and gene expression. Recent studies have shown that ROCKs may play a pivotal role in cardiovascular diseases such as vasospastic angina, ischemic stroke, and heart failure. Indeed, inhibition of ROCKs by statins or other selective inhibitors leads to the upregulation and activation of endothelial nitric oxide synthase (eNOS) and reduction of vascular inflammation and atherosclerosis.

View Article and Find Full Text PDF

Background: Rho GTPase and its downstream target, Rho-associated kinase (ROCK), have been implicated in diverse cardiovascular diseases such as cardiac hypertrophy. However, pharmacological inhibitors of ROCK are not entirely specific, nor can they discriminate between the ROCK isoforms ROCK1 and ROCK2. To determine the specific role of ROCK1 in the development of cardiac hypertrophy, we generated ROCK1(+/-) haploinsufficient mice and determined whether cardiac hypertrophy and remodeling are decreased in these mice.

View Article and Find Full Text PDF

The purpose of this article is to review the characteristics of computed tomography (CT) and magnetic resonance imaging (MRI) of the pericardium and pericardial diseases. Because patients with pericardial diseases usually present with nonspecific symptoms, these diseases may not be detected until they have reached an advanced stage. It is therefore important to distinguish between normal pericardial structure and disease.

View Article and Find Full Text PDF

Background: Enhanced expression of G protein-coupled receptor kinase (GRK) has been reported in failing hearts and in the present study the stability of enhanced GRK mRNA expression, and the correlation between the expression level of GRK mRNA in peripheral lymphocytes and in the heart were both evaluated.

Methods And Results: Isoproterenol was injected into rats for 2 weeks, and then GRK5 mRNA was assessed by quantitative reverse transcriptase-palymerase chain reaction. An enhanced expression of cardiac GRK5 mRNA was observed even after 4 weeks of recovery.

View Article and Find Full Text PDF

A 72-year-old woman was admitted to our institution because of sudden chest pain. Emergency coronary angiography revealed thrombotic occlusion of the distal right coronary artery. A large cylindrical thrombus was retrieved from her distal right coronary artery using a thrombus aspiration catheter.

View Article and Find Full Text PDF

Background: The aim of the present study was to describe the effectiveness and feasibility of high-resolution computed tomography (HRCT) in patients in supine and prone positions to detect amiodarone-induced pulmonary toxicity (APT). With regard to the possible differential diagnosis, our second goal was to emphasize the clinical value of HRCT with the patients in supine and prone positions compared with other paraclinical tests.

Methods And Results: Thoracic HRCT taken in both positions for 23 patients who were administrated amiodarone were prospectively evaluated in the current study.

View Article and Find Full Text PDF

Coronary vasomotor response to acetylcholine infusion was studied in a 69-year-old currently smoking man with enhanced insulin response to oral glucose load. Coronary angiogram showed no significant stenoses. Immediately after 20 microg acetylcholine infusion in the right coronary artery, angiographic no-flow, ischemic electrocardiographic changes, and anginal pain developed in the absence of epicardial coronary obstruction.

View Article and Find Full Text PDF

In a 54-year-old woman with liver cirrhosis who underwent orthotopic liver transplantation, the postoperative course was complicated by aneurysm formation in the hepatic artery. Abdominal ultrasonography showed a daily increase in size of the aneurysm in spite of careful management including strict rest and continuous intravenous infusion of antihypertensive agents. Since the patient's poor systemic status was a major obstruction to operative resection, transcatheter therapy was though more preferable.

View Article and Find Full Text PDF