James Mackenzie was a Scottish physician and one of the leading cardiologists in Europe at the turn of the 20th century. He was a prolific writer and contributed extensively to our understanding of cardiac diseases, particularly cardiac arrhythmias and heart failure.
Mackenzie had a great interest in the study of the arterial and venous pulses and cardiac arrhythmias. His famous ink polygraph appeared in 1892 and he was able to obtain simultanelously the tracing of several pulses. He identified extrasystoles in 1890 and recorded venous tracings with total irregularity compatible with atrial fibrillation. Of great interest is his description of a case in which a female patient with rheumatic mitral stenosis was followed by him for several years. The patient had a presystolic murmur at examination. Mitral valve obstruction worsened in this patient progressively. Mackenzie then noted the occurrence of cardiac arrhythmia with irregular venous tracings which coincided with the disapperance of the presystolic murmur. He initially called this entity "auricular paralysis". Later on, the observation of atrial hypertrophy in autopsy studies led him to abandon this view and influenced him in concluding that that the atria still had electrical activity which was completely disorganized. Mackenzie's investigations were published in a classic monograph, "The study of the pulse," which appeared in 1902. This topic is further discussed in the Sphygmography section.
Mackenzie also discussed the characteristics of cardiac murmur in mitral valve disease in his book, "Principles of diagnosis and treatment in heart affections", which appeared in 1916. The chapter on diastolic murmur of mitral stenosis : "When the murmurs of mitral stenosis appear , and how they alter" is displayed here.
Mackenzie's views of heart failure in patients with valvular pathology deserve to be analyzed as they influenced several generations of cardiologists during the first few decades of the 20th century. His observations were published in his important textbook, "Diseases of the heart," which was first published in 1908. The third revised edition of this work appeared in 1918.
Mackenzie was of the opinion that valvular diseases including mitral stenosis and regurgitation did not have any clinical significance unless myocardial failure has occurred. He considered that "valvular defects can embarrass the work of the heart." Regarding the potential clinical impact of mitral regurgitation, he wrote:
"The really serious trouble in connexion with mitral regurgitation arises when the muscle is impaired and the regurgitation is due to a complication of the dilated orifice and diseased valve. The subsequent results depend on the degree of the exhaustion of the muscle of the heart. The backward pressure resulting from the regurgitation embarrasses the left auricle. The exhaustion also affects the right ventricle and so adds to the embarrassment of the pulmonary circulation. While back-pressure is a factor of importance and may be a predisposing cause, yet it produces comparatively few symptoms until the tonicity gives away, which is manifested by dilatation of the heart...In fact, in the majority of cases, as Graham Steell says, "the change in the valves is altogether inadequate to explain the evidently free regurgitation that occurred during life, and the disastrous dilatation of the heart. The muscle-failure factor, it may be presumed, was the essential one"...It will thus be seen that the symptoms produced by mitral incompetence are only of gravity when there is also muscle failure."
The views of Mackenzie and some of his disciples that valve disease was of little importance compared to the myocardial function were questioned in the 1920's. The pioneering work of surgeons such as Cutler from Boston played a critical role as they placed the emphasis on valvular diseases and attempted to introduce innovative approcahes to treat effectively these affections. Culter performed the first surgical intervention for mitral stenosis in 1923. The same year, in the second edition of "the Principles of diagnosis and treatment in heart affections" Mackenzie wrote: "In these cases there are other factors present in addition to mitral stenosis. The muscle substance is not infrequently damaged and then heart failure is readily induced."
Later in 1925, Mackenzie added humbly the following comments: " How little is known about heart failure can be found by anyone who seeks for information in recent writings of cardiologists. It is perfectly evident that...a far more intimate knowledge of the manner in which the heart performs its work must be acquired , and that the conceptions which have guided investigations so far are unsuited to carry the matter far enough."