Background: It was not until 1919 that the diuretic properties of mercury were observed in patients with syphilis; in the same year the beneficial effects of mercurial diuretics were shown in a patient with severe rheumatic heart disease and anasarca. However, mercury had been used much earlier for the treatment of dropsy without clear guidelines. In this article we describe William Stokes' insights into the treatment of heart failure, focusing on the beneficial diuretic properties of mercury.
Methods: We reviewed the chapter "Treatment of the Weak and Probably Dilated Heart in Connexion With Enlargement of the Liver and Pulmonary Disease" in William Stokes' famous treatise The Diseases of the Heart and the Aorta.
Conclusions: Stokes makes several important clinical observations. First, he provides precise guidelines on when and how to use mercury in these patients. Second, he realizes the importance of mercury for the treatment of decompensated heart failure. Stokes recognizes the cyclical nature of frequent decompensation in congestive heart failure, the relationship of clinical deterioration and reduced urine output, and the importance of reestablishing urinary flow to ameliorate dyspnea. Third, he attempts to define the mechanism of action "... if any of the characteristic action of mercury can be perceived unless we include diuresis." Finally, he gives interesting guidelines on the dosage and side effects of mercury. These observations on the treatment of "congestive" heart failure are an important contribution to the understanding of heart failure pathophysiology and the design of prescription regimens for this disease.