Kai Hu

Publications (72) View all

• Article: Two-dimensional speckle tracking as a non-invasive tool for identification of myocardial fibrosis in Fabry disease.

  Johannes Krämer, Markus Niemann, Dan Liu, Kai Hu, Wolfram Machann, Meinrad Beer, Christoph Wanner, Georg Ertl, Frank Weidemann
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  ABSTRACT: AimsThis cross-sectional study aimed to analyse myocardial deformation in patients with Fabry disease (FD) in order to evaluate speckle tracking as a method for non-invasive determination of myocardial fibrosis. Myocardial fibrosis is common in Fabry cardiomyopathy and is associated with disease progression and severe prognosis.Methods and resultsIn 101 consecutive Fabry patients (39.8 ± 12.9 years; 42 males), the quantitative measurement of myocardial fibrosis with magnetic resonance imaging was compared with regional myocardial deformation assessed by speckle-tracking imaging. Patients were analysed in relation to per cent of late-enhancement (LE)-positive areas of left-ventricular (LV) mass. Fifty-two patients (51%) displayed LE with a mean volume of 1.2 ± 1.8% of total LV mass. Predominantly basal lateral and posterior segments were affected. Patients with LE had lower global systolic longitudinal strain than those without (LE -14.8 ± 3.5% and -18.9 ± 2.1%, respectively; P < 0.001). Loss of global deformation, quantified by speckle tracking, was predominantly caused by basal posterior (P = 0.049) and lateral (P = 0.005) segments and global systolic strain correlated with the amount of LE (r = 0.543; P < 0.001). Patients with severe LE (>2%, n = 22) showed the lowest deformation values (-5.9 ± 8.4%) in basal postero-lateral segments when compared with those with mild (<2%; n = 30, -7.1 ± 7.5%) or no LE (n = 49, -16.3 ± 3.3%). These changes were accompanied by thinning of the posterior wall and a decrease in diastolic function, whereas ejection fraction and LV end-diastolic diameter were not different. Receiver operating characteristic analysis revealed that the systolic strain of basal postero-lateral segments was the most powerful predictor to distinguish between patients with and without LE (sensitivity = 90%; specificity = 97%, area under the curve = 0.913; P < 0.001).Conclusions Late enhancement is associated with lower longitudinal strain in the fibrotic wall segments. Speckle tracking can be used as a tool for the indirect evaluation of LE in FD.
  European Heart Journal 03/2013; · 10.48 Impact Factor
• Article: Naoxintong Protects against Atherosclerosis through Lipid-lowering and Inhibiting Maturation of Dendritic Cells in LDL Receptor Knockout Mice fed a High-fat Diet.

  Jingjing Zhao, Hong Zhu, Shijun Wang, Xin Ma, Xiangwei Liu, Cong Wang, Hangtian Zhao, Shuxia Fan, Xueting Jin, Keqiang Wang, Yunzeng Zou, Kai Hu, Aijun Sun, Junbo Ge
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  ABSTRACT: Naoxintong (NTX), a Chinese Materia Medica standardized product, extracted from 16 various kinds of Chinese traditional herbal medicines including Salvia miltiorrhiza, Angelica sinennsis, Astragali Radix, is clinically effective in treating atherosclerosis-related diseases. Here, we tested the hypothesis that the anti-atherosclerosis effects of NTX might be mediated by suppressing maturation of dendritic cells (DCs) in a mice model of atherosclerosis.. LDLR-/- mice fed a high-fat diet were treated with placebo, NTX (0.7g/kg/d, oral diet) or simvastatin (100mg/kg/d, oral diet) for 8 weeks, respectively. NTX treatment significantly reduced plasma triglyceride (112±18 mg/dl vs. 192±68 mg/dl, P<0.05) and total cholesterol (944±158 mg/dl vs. 1387±208 mg/dl, P<0.05) compared to placebo treatment. Vascular lesions were significantly smaller and macrophage content and amount of DCs in plaques were significantly less in NTX and simvastatin groups than in placebo group (all P<0.05). In addition, plasma levels of splenic DC membrane molecules (CD40, CD86 and CD80) and IL-12p70 were significantly lower in NTX and simvastatin groups than in placebo group. In conclusion, NTX protects against atherosclerosis through lipid-lowering and inhibiting DCs maturation in this mice model of atherosclerosis.
  Current pharmaceutical design 02/2013; · 4.41 Impact Factor
• Article: MicroRNA-34a Promotes Cardiomyocyte Apoptosis Post Myocardial Infarction Through Down-regulating Aldehyde Dehydrogenase 2.

  Fan Fan, Aijun Sun, Hangtian Zhao, Xiangwei Liu, Wenbin Zhang, Xueting Jin, Cong Wang, Xin Ma, Cheng Shen, Yunzeng Zou, Kai Hu, Junbo Ge
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  ABSTRACT: MicroRNA-34a (miR-34a) promotes apoptosis via down-regulating many anti-apoptotic proteins. Aldehyde dehydrogenase 2 (ALDH2) is an anti-apoptotic enzyme whose activity decline associates with myocardial injury. We tested hypothesis that miR-34a might play a pro-apoptotic role in myocardial infarction (MI) by down-regulating ALDH2. MiR-34a was highly increased while ALDH2 expression was decreased after experimental MI. Overexpression of miR-34a in neonatal rat cardiomyocyte could significantly enhance apoptosis and down-regulate ALDH2 expression. In 293 cells, luciferase reporter assay results demonstrated that ALDH2 was a direct target of miR-34a. Serum miR-34a levels in acute myocardial infarction (AMI) patients and rats were significantly higher than healthy subjects and sham rats. Our results proved that miR-34a could promote cardiomyocyte apoptosis via negatively regulating ALDH2 and circulating miR-34a was increased in the condition of MI. Thus, miR-34a may constitute a new therapeutic target and diagnostic marker for patients with MI.
  Current pharmaceutical design 01/2013; · 4.41 Impact Factor
• Article: Impact of regional left ventricular function on outcome for patients with Al amyloidosis.

  Dan Liu, Kai Hu, Markus Niemann, Sebastian Herrmann, Maja Cikes, Stefan Störk, Meinrad Beer, Philipp Daniel Gaudron, Caroline Morbach, Stefan Knop, Eva Geissinger, Georg Ertl, Bart Bijnens, Frank Weidemann
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  ABSTRACT: The aim of this study was to explore the left ventricular (LV) deformation changes and the potential impact of deformation on outcome in patients with proven light-chain (AL) amyloidosis and LV hypertrophy. Cardiac involvement in AL amyloidosis patients is associated with poor outcome. Detecting regional cardiac function by advanced non-invasive techniques might be favorable for predicting outcome. LV longitudinal, circumferential and radial peak systolic strains (Ssys) were assessed by speckle tracking imaging (STI) in 44 biopsy-proven systemic AL amyloidosis patients with LV hypertrophy (CA) and in 30 normal controls. Patients were divided into compensated (n = 18) and decompensated (n = 26) group based on clinical assessment and followed-up for a median period of 345 days. Ejection fraction (EF) was preserved while longitudinal Ssys (LSsys) was significantly reduced in both compensated and decompensated groups. Survival was significantly reduced in decompensated group (35% vs. compensated 78%, P = 0.001). LSsys were similar in apical segments and significantly reduced in basal segments between two patient groups. LSsys at mid-segments were significantly reduced in all LV walls of decompensated group. Patients were further divided into 4 subgroups according to the presence or absence of reduced LSsys in no (normal), only basal (mild), basal and mid (intermediate) and all segments of the septum (severe). This staging revealed continuously worse prognosis in proportion to increasing number of segments with reduced LSsys (mortality: normal 14%, mild 27%, intermediate 67%, and severe 64%). Mid-septum LSsys<11% suggested a 4.8-fold mortality risk than mid-septum LSsys≥11%. Multivariate regression analysis showed NYHA class and mid-septum LSsys were independent predictors for survival. Reduced deformation at mid-septum is associated with worse prognosis in systemic amyloidosis patients with LV hypertrophy.
  PLoS ONE 01/2013; 8(3):e56923. · 4.09 Impact Factor
• Article: Methods for Assessment of Left Ventricular Systolic Function in Technically Difficult Patients with Poor Imaging Quality.

  Kai Hu, Dan Liu, Markus Niemann, Sebastian Herrmann, Philipp Daniel Gaudron, Georg Ertl, Frank Weidemann
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  ABSTRACT: The assessment of left ventricular (LV) systolic function is often the most important information obtained during clinical echocardiography. Although LV systolic function may be visually estimated in many patients with or without contrast opacification, technically difficult patients may require alternative methods for evaluating LV systolic function. In this review, the authors describe several surrogate echocardiographic methods that might be helpful for the evaluation of LV systolic function in patients with poor image quality, including endocardial border delineation by contrast agents, mitral annular plane systolic excursion, mitral annular velocity derived from tissue Doppler, systolic time intervals, mitral regurgitation-derived LV dP/dt, and estimation of cardiac output by Doppler echocardiography. After a short introduction to the various issues involved, the authors propose a method for suitable measurement. In addition, indications and clinical implications, as well as limitations, of the different methods are discussed.
  Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 12/2012; · 2.98 Impact Factor