Excerpt from Text-Book on Diseases of the Heart Thus it became necessary to indicate, in the text, the lines along which knowledge has recently progressed, and is likely in the future to progress, and the work of Mackenzie and Wenckebach has been specially drawn upon for the purpose. It must not be supposed, however, that the advance in our knowledge referred to had been preceded by a prolonged period of stand-still. This is very far from being the case: though progress had been slow, it had been steady. In 1873 the writer had the good fortune of being House Physician to the late Dr. G. W. Balfour, in the Edinburgh Royal Infirmary, and he well remembers how the views of his master were, then, regarded. The great work done by Balfour can hardly be realised now: suffice it to say that up to that time the prevailing idea had been that mitral disease and mitral incompetence were practically equivalent terms. That this was so seems all the more strange in view of the fact that every physiology text-book of the period taught the so-called safety-valve action of the tricuspid-valve apparatus. The application of the same principle to the mitral-valve apparatus was not made earlier no doubt because of the great proclivity to disease of the valves of the left ventricle in comparison with the practical immunity of those of the right ventricle. Curable mitral regurgitation was the term used by Balfour to call attention to the then new doctrine, the cases he took for illustration being chiefly examples of chlorosis. Unfortunately, all cases of mitral regurgitation the result of muscle failure are not curable, inasmuch as the cause of the muscle failure cannot be removed as it can be in chlorosis. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.