TORSIONAL DEFORMATION OF THE LEFT-VENTRICULAR MIDWALL IN HUMAN HEARTS WITH INTRAMYOCARDIAL MARKERS - REGIONAL HETEROGENEITY AND SENSITIVITY TO THE INOTROPIC EFFECTS OF ABRUPT RATE CHANGES
TORSIONAL DEFORMATION OF THE LEFT-VENTRICULAR MIDWALL IN HUMAN HEARTS WITH INTRAMYOCARDIAL MARKERS - REGIONAL HETEROGENEITY AND SENSITIVITY TO THE INOTROPIC EFFECTS OF ABRUPT RATE CHANGES
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DOI：
10.1161/01.res.62.5.941
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发表时间：
1988-05-01
影响因子：
20.1
通讯作者：
MILLER, DC
中科院分区：
文献类型：
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作者：
HANSEN, DE;DAUGHTERS, GT;MILLER, DC
左心室（LV）纤维的螺旋取向表明，围绕心尖相对于基底的心室长轴的扭曲，即，扭转变形可能是LV收缩的特征。为了证明这种扭转运动，我们对10例原位人类心脏移植受者进行了研究，在12个特定部位的左心室中壁植入钽螺旋的双平面放射电影摄影。所有患者左心室长轴逆时针扭转（从心尖到基底）伴心室射血。相对于基部的参考短轴测量的扭转变形角，与下壁和侧壁的顶端三分之一中的对应物相比，前顶壁中的扭转变形角显著较小（前= 13.3 ± 1.5）。6.0 °，横向= 23.4 .+-. 10.7 °）。在心室中部水平的扭转角大约是一半，并表现出类似的区域变异性（前= 7.6 ± 0.01）。3.3 °，劣= 9.0 .+-。3.3 °，横向= 10.7 .+-. 5.2 °，间隔= 8.8 ±. 3.8 °）。快速心房起搏突然停止后控制搏动和初始搏动的比较（126 . ±. 10次/分钟），并恢复到对照心率（96 . ±. 9次/分）允许在相似的心室负荷水平下评估心动过速的轻度正性肌力作用。前根尖和下根尖部位的扭转变形比对照值显著增加（p < 0.05）至15.6 ± 0.05。7.5.degree.和21.2 .+-。5.5 °，分别相反，侧壁的扭转变形基本不变。这些数据提供了人类左心室扭转变形的直接证据，证明左心室腔室的扭转是不均匀的，并表明左心室扭转依赖于侧壁中衰减的收缩强度。
The spiral orientation of left ventricular (LV) fibers suggests that twisting about the ventricular long axis of the apex with respect to the base, i.e., torsional deformation, may be characteristic of LV contraction. To demonstrate this twisting motion, 10 orthotopic human cardiac allograft recipients were studied with biplane cineradiography of tantalum helices implanted within the LV midwall at 12 specific sites. Counterclockwise twisting about the LV long axis (as reviewed from apex to base) accompanied ventricular ejection in all patients. Torsional deformation angles, measured relative to a reference minor axis at the base, were substantially smaller in the anteroapical wall, as compared with counterparts in the apical third of the inferior and lateral walls (anterior = 13.3 .+-. 6.0.degree., lateral = 23.4 .+-. 10.7.degree.). Torsional angles at the midventricular level were roughly half as much and exhibited similar regional variabilities (anterior = 7.6 .+-. 3.3.degree., inferior = 9.0 .+-. 3.3.degree., lateral = 10.7 .+-. 5.2.degree., and septal = 8.8 .+-. 3.8.degree.). Comparison of control beats and the initial beat after abrupt cessation of rapid atrial pacing (126 .+-. 10 beats/min) with return to the control heart rate (96 .+-. 9 beats/min) permitted the mild positive inotropic effect of tachycardia to be assessed at similar levels of ventricular load. Torsional deformation of the anteroapical and inferoapical sites increased significantly (p < 0.05) over control values to 15.6 .+-. 7.5.degree. and 21.2 .+-. 5.5.degree., respectively. In contrast, torsional deformation of the lateral wall was essentially unchanged. These data provide direct evidence for torsional deformation of the left ventricle in humans, demonstrate that torsion of the LV chamber is nonuniform, and suggest a dependence of LV torsion upon contractile strength that is attenuated in the lateral wall.