Xiao H B, Gibson D G
Cardiac Department, Royal Brompton National Heart and Lung Hospital, London.
Br Heart J. 1994 Jul;72(1):45-51. doi: 10.1136/hrt.72.1.45.
To investigate the possible mechanical associations of the presence or absence of the septal q wave.
Retrospective and prospective study of 63 patients with various left ventricular diseases and 10 controls by electrocardiography, echocardiography, and pulsed Doppler recordings.
Tertiary cardiac referral centre.
73 subjects were studied. 26 had absent septal q waves and a QRS duration < 120 ms, 25 had classic left bundle branch block, and the rest had a normal electrocardiogram. Pathologically, 34 had left ventricular disease and 29 had a structurally normal heart. 10 subjects with structurally normal hearts and normal septal q waves were taken as controls.
The timing of left ventricular minor axis motion was consistently normal in patients with abnormal activation, but long axis motion was considerably altered, with delayed "post-ejection shortening" of a mean amplitude of 4 mm. The post-ejection shortening began 10 (15) ms and reached its peak 90(20) ms after aortic closure (A2). Peak lengthening rate did not differ from normal (6.2 (3.5) v 8.5 (3.5) cm/s, NS) though it occurred significantly later. Post-ejection shortening was unrelated to age, amplitude of left ventricular wall motion, or QRS axis on the surface electrocardiogram. Post-ejection shortening was commoner when QRS duration was > 115 ms, but an absent septal q wave predicted its presence with a specificity of 90% and sensitivity of 86%. In patients with a post-ejection shortening, the onset of left ventricular systolic long axis shortening was delayed and the extent of its lengthening during the pre-ejection period increased, indicating delayed and incoordinate onset of tension development. During diastole, post-ejection shortening was associated with a prolonged isovolumic relaxation period and the time from A2 to the onset of transmitral flow. Peak mitral E wave flow velocity was reduced due to a fall in acceleration time although acceleration rate itself was unchanged.
Loss of the normal septal q wave is associated with considerable mechanical consequences throughout the cardiac cycle, from the pre-ejection period to atrial systole, and apparently causes asynchronous subendocardial function.
研究间隔q波存在与否可能的机械关联。
对63例患有各种左心室疾病的患者和10例对照者进行回顾性和前瞻性研究，采用心电图、超声心动图和脉冲多普勒记录。
三级心脏转诊中心。
共研究了73名受试者。26例间隔q波缺失且QRS时限<120 ms，25例有典型左束支传导阻滞，其余心电图正常。病理检查发现，34例有左心室疾病，29例心脏结构正常。选取10例心脏结构正常且间隔q波正常的受试者作为对照。
激活异常的患者左心室短轴运动时间始终正常，但长轴运动有显著改变，“射血后缩短”延迟，平均幅度为4 mm。射血后缩短在主动脉瓣关闭（A2）后10（15）ms开始，90（20）ms达到峰值。峰值延长率与正常情况无差异（6.2（3.5）对8.5（3.5）cm/s，无显著性差异），尽管其发生时间明显延迟。射血后缩短与年龄、左心室壁运动幅度或体表心电图QRS轴无关。当QRS时限>115 ms时，射血后缩短更为常见，但间隔q波缺失预测其存在的特异性为90%，敏感性为86%。在有射血后缩短的患者中，左心室收缩期长轴缩短的起始延迟，射血前期其延长程度增加，表明张力发展延迟且不协调。在舒张期，射血后缩短与等容舒张期延长以及从A2到二尖瓣血流开始的时间相关。由于加速时间缩短，二尖瓣E波峰值流速降低，尽管加速率本身未改变。
正常间隔q波的缺失在整个心动周期中，从射血前期到心房收缩期，都伴有相当大的机械后果，并且显然会导致心内膜下功能不同步。
