Publications by authors named "Kana Yazaki"

Article Synopsis
  • The study investigates how the right ventricle (RV) of the heart remodels in response to increased pressure over a span of six weeks, focusing on the early changes that could inform treatment timing.
  • Researchers found that within the first week after introducing pressure (using pulmonary artery banding), there was a significant inflammatory response and changes in cellular metabolism that suggested RV stress.
  • The findings imply that detrimental changes in RV function start earlier than previously thought, indicating that interventions to prevent RV remodeling may need to happen sooner than current practices suggest.
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Background: Right ventricular (RV) hemodynamic performance determines the prognosis of patients with RV pressure overload. Using ultrafast ultrasound, natural wave velocity (NWV) induced by cardiac valve closure was proposed as a new surrogate to quantify myocardial stiffness.

Objectives: This study aimed to assess RV NWV in rodent models and children with RV pressure overload vs control subjects and to correlate NWV with RV hemodynamic parameters.

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Right ventricular (RV) fibrosis is associated with RV dysfunction in a variety of RV pressure-loading conditions where RV mechanical stress is increased, but the underlying mechanisms driving RV fibrosis are incompletely understood. In pulmonary and cardiovascular diseases characterized by elevated mechanical stress and transforming growth factor - beta-1 (TGF-β1) signaling, myocardin-related transcription factor A (MRTF-A) is a mechanosensitive protein critical to driving myofibroblast transition and fibrosis. Here we investigated whether MRTF-A inhibition improves RV pro-fibrotic remodeling and function in response to a pulmonary artery banding (PAB) model of RV pressure-loading.

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Background: Cardiac dysfunction due to cardiotoxicity from anthracycline chemotherapy is a leading cause of morbidity and mortality in childhood cancer survivors (CCS), and the cumulative incidence of cardiac events has continued to increase. This study identifies an adequate indicator of cardiac dysfunction during long-term follow-up.

Procedure: In total, 116 patients (median age: 15.

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Article Synopsis
  • * It included 47 patients with ulcerative colitis, 20 with Crohn's disease, and 75 healthy controls, measuring different layers of heart strain through echocardiography.
  • * Results showed lower global longitudinal strain across all layers for both UC and CD patients, while midmyocardial and epicardial strain was particularly lower in Crohn's disease patients, indicating potential heart dysfunction related to their condition.
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Article Synopsis
  • Abnormal electrical conduction and fRV dysfunction are common issues in patients with Ebstein anomaly (EA), leading to poor fRV function and exercise intolerance.
  • A study analyzing 35 EA patients and age-matched controls found that EA patients exhibited significantly worse RV function and increased mechanical dyssynchrony compared to controls.
  • fRV mechanical dyssynchrony correlated with various measurements of fRV size and function, indicating its potential role in the impaired exercise capacity of EA patients.
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Pulmonary regurgitation (PR) after repair of tetralogy of Fallot (rTOF) is associated with progressive right (RV) and left (LV) ventricular dysfunction and fibrosis. However, angiotensin II receptor blockade therapy has shown mixed and often disappointing results. The aim of this study was to serially assess changes in biventricular remodeling, dysfunction, and interactions in a rat model of isolated severe PR and to study the effects of angiotensin II receptor blockade.

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This study was aimed to assess the outcomes of simultaneous phototherapeutic keratectomy (PTK) and photoastigmatic keratectomy (PAK), with special attention to astigmatic correction. We comprised 70 eyes of 70 patients who underwent simultaneous PTK and PAK in patients having granular corneal dystrophy and band keratopathy with refractive astigmatism of 1 diopter (D) or more. Preoperatively and 6 months postoperatively, we assessed corrected uncorrected distance visual acuity (UDVA), distance visual acuity (CDVA), manifest spherical equivalent, refractive astigmatism, corneal astigmatism, and higher-order aberrations (HOAs).

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Introduction: Exercise stress echocardiography and layer-specific strains are emerging as important tools for cardiac assessment. This study was aimed to evaluate layer-specific strains and torsion parameters during exercise in order to investigate the characteristics of cardiac dysfunction in patients with repaired tetralogy of Fallot and to detect subclinical left ventricular dysfunction.

Materials And Methods: Thirteen patients with repaired tetralogy of Fallot (median age, 17.

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Article Synopsis
  • Vorticity is a new measure that helps assess how well the left ventricle of the heart functions during the diastolic phase, which is when the heart fills with blood.
  • The size of the ventricle can greatly affect how blood flows during this filling phase, and the study evaluated this impact using a variety of dog breeds with different body sizes.
  • Results showed that vorticity decreases as the ventricular chamber length increases, indicating that size plays a crucial role in diastolic function, highlighting the importance of considering ventricular size in both veterinary medicine and pediatric cardiology.
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Background: Although the subclinical left ventricular (LV) dysfunction caused by diabetes mellitus (DM) results in a high risk of death and heart failure, the details of cardiac dysfunction across a wide age range remain unclear. The aim of this study was to assess LV dysfunction in patients with type 1 DM (T1DM) using layer-specific strain analysis by echocardiography.

Methods and results: The 52 patients (median age: 23 [range: 5-40] years) with T1DM were divided into 3 age groups (D1: 5-14 years, D2: 15-24 years, D3: 25-40 years); 78 age- and sex-similar controls were divided into 3 corresponding groups (C1, C2, and C3).

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Cardiac dysfunction due to cardiotoxicity from anthracycline chemotherapy is a leading cause of morbidity and mortality in survivors of childhood cancer. The intraventricular pressure gradient (IVPG) of the left ventricle (LV) is the suction force of blood from the left atrium to the LV apex during early diastole and is a sensitive indicator of diastolic function. We assessed IVPG as a new indicator of the cardiac dysfunction in survivors of childhood cancer after anthracycline therapy.

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Although the suction force that moves blood into the left ventricle during early diastole is thought to play an important role in diastolic function, there have been a few studies of this phenomenon in normal children. Suction force is measured as the intraventricular pressure difference (IVPD) and intraventricular pressure gradient (IVPG), which is calculated as IVPD divided by left ventricular length. The purpose of this study was to determine the suction force in infants, children, and adolescents using IVPD and IVPG.

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Background: Anthracycline cardiotoxicity affects clinical outcomes, and its early detection using methods that rely on conventional echocardiography, such as left ventricular ejection fraction (LVEF) is difficult. This study aimed to evaluate the characteristics and the differences in cardiac dysfunction among childhood cancer survivors in 3 age groups using layer-specific strain analysis in a wide age range.

Methods and results: The 56 patients (median age: 15 [range: 6.

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Assessment of left ventricular (LV) dysfunction is vital in patients with repaired tetralogy of Fallot (rTOF). The early diastolic intraventricular pressure gradient (IVPG) in the LV plays an important role in diastolic function. IVPG is calculated as the intraventricular pressure difference divided by the LV length, which allows to account for differences in LV size and therefore calculate IVPG in children.

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Background: Left ventricular (LV) dysfunction in patients with repaired tetralogy of Fallot (rTOF) is an important risk factor for adverse outcomes. The aim of this study was to assess the details and time course of such LV dysfunction using layer-specific strain analysis by echocardiography.Methods and Results:The 66 patients with rTOF (mean age, 16.

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