Rahko P S, Shaver J A, Salerni R
Department of Medicine, University of Wisconsin Medical School, Madison.
J Am Coll Cardiol. 1993 Apr;21(5):1114-23. doi: 10.1016/0735-1097(93)90233-q.
The purpose of this study was to evaluate functional and hemodynamic factors that determine the mitral-tricuspid and aortic-pulmonary valve closure sequence in patients with dilated cardiomyopathy.
The physiologic factors determining closure sequence of cardiac valves in various forms of heart disease have been found to be complex. Few data exist for dilated cardiomyopathy, particularly for differentiating the effects of a conduction delay versus changes in ventricular performance.
A group of 64 patients were compared with 36 control subjects. Timing of valve closure and electromechanical intervals were determined by combined M-mode echocardiography, phonocardiography and apexcardiography. Hemodynamic data from right heart catheterization were available in 46 patients.
In all control subjects, the aortic valve closed before the pulmonary valve and the mitral valve closed before the tricuspid valve. In the study group, 30 patients (49%) had reversed aortic-pulmonary valve closure and 27 (90%) of these had a left-sided conduction delay. There were 38 patients (60%) who had reversed mitral-tricuspid valve closure, but this was unrelated to the presence of a left-sided conduction delay. The presence of high ventricular filling pressures and poor systolic function was associated with delayed closure of both the mitral and the tricuspid valve. This caused the closure sequence to be related to the size of the difference between mean pulmonary artery wedge pressure and mean central venous pressure and also the magnitude of right ventricular dysfunction. Patients with a low wedge pressure (< 16 mm Hg) and a low central venous pressure (< 10 mm Hg) had a low prevalence of mitral-tricuspid valve closure reversal (30%). Those with a high wedge pressure (> 16 mm Hg) but a low central venous pressure had a high prevalence (86%) of reversal of mitral-tricuspid valve closure. Patients with high wedge and central venous pressures had a moderate prevalence (47%) of mitral-tricuspid valve closure reversal. Similar findings were observed for right ventricular dysfunction. If the right ventricle was normal or severely dysfunctional, a reversed closure sequence was less common (52% and 41%, respectively) than if moderate dysfunction was present (78%).
Aortic-pulmonary valve closure sequence is strongly related to the presence of a left-sided conduction delay. The mitral-tricuspid valve closure sequence is unrelated to a conduction delay but can be reversed by relative differences in the severity of systolic dysfunction and filling pressures between the two ventricles.
本研究旨在评估决定扩张型心肌病患者二尖瓣-三尖瓣及主动脉瓣-肺动脉瓣关闭顺序的功能和血流动力学因素。
已发现决定各种形式心脏病中心脏瓣膜关闭顺序的生理因素很复杂。关于扩张型心肌病的数据很少，尤其是区分传导延迟与心室功能变化的影响。
将一组64例患者与36例对照者进行比较。通过M型超声心动图、心音图和心尖搏动图联合测定瓣膜关闭时间和机电间期。46例患者可获得右心导管检查的血流动力学数据。
在所有对照者中，主动脉瓣在肺动脉瓣之前关闭，二尖瓣在三尖瓣之前关闭。在研究组中，30例患者（49%）出现主动脉瓣-肺动脉瓣关闭顺序逆转，其中27例（90%）存在左侧传导延迟。有38例患者（60%）出现二尖瓣-三尖瓣关闭顺序逆转，但这与左侧传导延迟的存在无关。高心室充盈压和收缩功能差与二尖瓣和三尖瓣的延迟关闭有关。这导致关闭顺序与平均肺动脉楔压和平均中心静脉压之间差异的大小以及右心室功能障碍的程度有关。楔压低（<16 mmHg）且中心静脉压低（<10 mmHg）的患者二尖瓣-三尖瓣关闭顺序逆转的发生率低（30%）。楔压高（>16 mmHg）但中心静脉压低的患者二尖瓣-三尖瓣关闭顺序逆转的发生率高（86%）。楔压和中心静脉压均高的患者二尖瓣-三尖瓣关闭顺序逆转的发生率中等（47%）。右心室功能障碍也观察到类似结果。如果右心室正常或严重功能障碍，关闭顺序逆转的情况比中度功能障碍时少见（分别为52%和41%）（中度功能障碍时为78%）。
主动脉瓣-肺动脉瓣关闭顺序与左侧传导延迟的存在密切相关。二尖瓣-三尖瓣关闭顺序与传导延迟无关，但可因两个心室收缩功能障碍和充盈压严重程度的相对差异而逆转。
