Remarks on Failure of the Heart from Overstrain
Remarks on Failure of the Heart from Overstrain
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关于劳损心力衰竭的论述
DOI：
10.1136/bmj.2.1459.1321
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发表时间：
1888
影响因子：
--
通讯作者：
J. Adami
中科院分区：
文献类型：
--
作者：
Roy;J. Adami
更频繁地受到影响。众所周知，某些形式的心脏病，即所谓的心脏“过度劳累”，是由于心脏被要求完成的工作超过了它在不损害其复杂机制的某一部分的情况下所能完成的工作。这种形式的过度劳损的主要公认的原因是积极或长时间的肌肉运动，我们知道，这涉及到比平均正常更高的动脉压，并增加血液供应的收缩肌肉。此外，人们还认识到，除了上述这些疾病之外，还有许多其他疾病会增加心脏的负担，并可能导致器官疾病，如某些形式的急性或慢性肾脏疾病、梅毒，以及一般情况下动脉血压高于正常水平的所有这些疾病。在某些情况下，引起这种情况的心脏疾病主要表现在瓣膜上；而对另一些人来说，器官的肌肉壁是过度劳累影响最明显的部分。我们还可以提到，在瓣膜疾病中，无论如何产生，功能不全或狭窄的影响是给心脏增加更多的工作，因此瓣膜疾病的一个主要结果是增加器官或部分器官的工作。因此，过度工作的病理必然是瓣膜疾病导致心脏衰竭的病理基础。lWhen也从任何引起心脏的肌肉力量减弱,无论是不完美的供血,脂肪变性,或血液质量受损,或从任何已知的许多原因,心脏的收缩的力量受损,我们有条件的所需的工作关系的器官和它的力量在一个类似的方式影响工作,发生在心脏的工作增加,它的力量是不变的。这些考虑促使我们做了一系列的实验，研究在健康和疾病的情况下，心脏被要求进行的工作的变化对心脏的影响。说到心脏所做的功，我们指的是器官在一定时间内所做的功的机械单位，它可以用心脏排出的血量乘以血液排出的压力来求得；也就是说，要考虑两个因素——心室在给定时间内排出的血液量和动脉压。因此，在研究心脏的工作与其对器官的作用之间的关系时，我们必须处理这两个因素。它们最容易被分开考虑，而且这种分开考虑或调查在许多情况下是可取的，因为它们作为疾病的原因并不一定是同时发生的；事实上，在某些情况下，其中一个可能是唯一活跃的。[1459]在血压计中的变化；最重要的是，我们来看看动脉压力的变化对心脏的影响，我们要说的是对左右心脏的影响是一样的。当然，用人类的方法来实验性地改变动物的动脉压是很容易的。例如，通过刺激
more frequently affected. It is known, also, that certain forms of heart disease, socalled "ooverstrain" of the heart, are due to the organ being called upon to perform more work than it is capable of compassing without harm to one or other part of its complicated mechanism. The chief recognised cause of this form of overstrain is active or prolonged muscular exertion, which, as we know, involves a higher arterial pressure than the mean normal, and an increased supply of blood to the contracting muscles. It is, moreover, recognised that there are many other conditions besides those mentioned which throw increased work upon the heart, and which may lead to disease of the organ, such as certain forms of acute or chronic renal disease, syphilis, and, in genaeral, all those conditions in which the arterial blood-pressure is higher than normal. The diseases of the heart which result in such cases are, in some instances, chiefly evident in the valves; while in others the muscular wall of the organ is the part in which the effects of the overwork are most marked. We may mention, also, that in disease of the valves, however produced, the effect of the incompetence or stenosis is to throw more work upon the heart, so that one main result of valvular disease is to increase the work of the organ, or part of the organ. The pathology, therefore, of overwork necessarily underlies the pathology of failure of the heart from disease of its valves. lWhen, also, from any cause the muscular power of the heart is diminished, whether from imperfect blood-supply, fatty degeneration, or impaired quality of the blood, or from any of the many known causes by which the power of contraction of the heart is impaired, we have a condition in which the relation between the work required of the organ and its power of doing that work is affected in an analogous way to that which occurs when the work of the heart is increased, and its power remains constant. These considerations induced us to make a series of experiments on the effect upon the heart of variations in the work which it is called upon to perform in conditions of health and disease. Inspeakingof thework doneby the lheart, werefer to the mechanical units of work done by the organ in a certain given time, and whiclh can be foundbymultiplyingthe quantity of brood thrownout by the heart by the pressure against which that blood is thrown out; that is, the two factors to be considered are-the quantity of blood expelled by the ventricles in a given time, and the arterial pressure. Thus, in investigating the relation of the work of the hleart to the effects of that work upoIn the organ, it is with these two factors that we have to deal. They can most conveniently be considered separately, and such separate consideration or investigation is, many cases, desirable, seeing that as causes of disease they do not necessarily go hand-in-hand; indeed, in certain caes one of them may be exclusively active. [1459] CUANGES IN THE BLOOD-PRESS';BE. Let us take, frit of all, the effect upon the heart of changes in he artenral ressure, what we have to say applying equally to the eft and to the right heart. It is, of course, easy to vary the arterial pres.sure experimentily in animals by manly methods. For example, by stimulation