Study for the mechanism of mechanical alternans

机械交替机理研究

• 批准号: 18590763
• 负责人: KODAMA Makoto
• 金额: $ 2.55万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18590763/
• 关键词: mechanical alternans; electrical alternans; heart failure; sudden death; force-frequency relationship; interval-force relationship; pressure-volume curve; 交互脈; リモデリング; 予後予測因子; 慢性心不全; 心室細動; 頻度伸縮性特性

Mechanical alternans is a poorly-understood phenomenon of alternating strong and weak beats with a constant beat-to-beat interval. It is a possible linker between failing myocardium and ventricular fibrillation in patients with chronic heart failure. Interval-force relationship, so-called mechanical restitution, is an intrinsic regulatory principle of myocardial contractility depending on sarcoplasmic reticulum (SR)Ca^(2+) cycling. Force-frequency relationship is also considered to reflect Ca^(++) handling of SR. We analyzed interval-force relationship and force frequency relationship in patients with chronic heart failure. In patients with atrial fibrillation, mechanical restitution curves were able to be obtained from beat by beat variance of left ventricular contractility adjusted by pre-preceding coupling intervals. We estimated mechanical restitution curves by fitting to monoexponential curves. Tau of the mechanical restitution curve increased in accord with the decrease of ejection fraction. We analyzed force-frequency relationship. In patients with chronic heart failure, peak force rate shifted to lower heart rate. The force gain of patients was little. A force gain was correlated to the left ventricular ejection fraction. We were able to obtain adequate mechanical restitution curves after both strong beats and weak beats from some patients. Mechanical restitution curves after weak beats steeply rose compared with those after strong beats. The time constant after weak beats were shorter than those after strong beats. Thus mechanical restitution properties were different after strong beats and weak beats during mechanical alternans. This implies that mechanical alternans originates from alternating changes of myocardial Ca^(2+) cycling property.

机械交替是一种人们知之甚少的现象，即以恒定的节拍间隔交替强弱节拍。它可能是慢性心力衰竭患者心肌衰竭和心室颤动之间的联系。间隔力关系，即所谓的机械恢复，是心肌收缩力依赖于肌浆网（SR）Ca^(2+)循环的内在调节原理。力-频率关系也被认为反映了 SR 的 Ca^(++) 处理。我们分析了慢性心力衰竭患者的间隔-力关系和力频率关系。在房颤患者中，通过预先耦合间隔调整的左心室收缩力的逐次搏动方差可以获得机械恢复曲线。我们通过拟合单指数曲线来估计机械恢复曲线。机械恢复曲线的Tau随着射血分数的降低而增加。我们分析了力-频率关系。在慢性心力衰竭患者中，峰值力速率转变为较低心率。患者的力量增益很小。力增益与左心室射血分数相关。我们能够从一些患者的强搏动和弱搏动后获得足够的机械恢复曲线。与强搏动后相比，弱搏动后的机械恢复曲线急剧上升。弱搏动后的时间常数比强搏动后的时间常数短。因此，在机械交替期间，强搏动和弱搏动后的机械恢复特性是不同的。这意味着机械交替源于心肌 Ca^(2+) 循环特性的交替变化。

项目成果

Angiopoietin-1, angiopoietin-2 and tie-2 in the coronary circulation of patients with and without coronary collateral vessels.

• DOI: 10.1253/circj.71.343
• 发表时间: 2007-02
• 期刊: Circulation journal : official journal of the Japanese Circulation Society
• 作者: W. Mitsuma;M. Kodama;S. Hirono;M. Ito;M. Ramadan;Komei Tanaka;Makoto Hoyano;T. Saigawa;T. Kashimura;K. Fuse;Y. Okura;Y. Aizawa

Clinical characteristics, treatment; and outcome of tachycardia induced cardiomyopathy

• DOI: 10.1536/ihj.49.39
• 发表时间: 2008-01-01
• 期刊: INTERNATIONAL HEART JOURNAL
• 影响因子: 1.5
• 作者: Watanabe, Hiroshi;Okamura, Kazuki;Aizawa, Yoshifusa
• 通讯作者: Aizawa, Yoshifusa

Angiopoietin-1, Angiopoietin-2 and Tie-2 in the Coronary Circulation of Patients with and without Coronary Collaterai Vessels.

有或没有冠状动脉侧支血管的患者冠状动脉循环中的血管生成素-1、血管生成素-2 和 Tie-2。

• 发表时间: 2007
• 期刊: Circ J 71
• 作者: Wataru Mitsuma;他
• 通讯作者: 他

Impact of percutaneous coronary intervention on the levels of interleukin-6 and C-reactive protein in the coronary circulation a subjects with coronary artery disease.

经皮冠状动脉介入治疗对冠状动脉疾病患者冠状动脉循环中白细胞介素 6 和 C 反应蛋白水平的影响。

• 发表时间: 2006
• 期刊: Am J Cardiol 98
• 作者: Malimoud M Ramadan;Makoto Kodama;et al.
• 通讯作者: et al.

Left ventricular pressure-volume loops during mechanical alternans in a patient with dilated cardiomyopathy

扩张型心肌病患者机械交替期间的左心室压力-容量环

• 发表时间: 2007
• 期刊: Heart 93
• 作者: Kashimura;T;Kodama;M;Aizawa;Y
• 通讯作者: Y