. Diseases of the heart and thoracic aorta. s which have been advocated, possibly hold true. Space does notpermit me to consider the arguments for and against these various theories indetail. Those readers who are interested in the subject should consult thewritings, more especially of Drs Barr and Sansom, where they will find fulldetails.—(See articles in the Medical Times and Gazette of January and February1877, and in the Liverpool Medico-Chirii7gical yourJial, July 1882, by Dr Barr ;and Diagnosis of Diseases of the Heart, by Dr Sansom, p. io5, et seq.) ^ Asynchronism, without any diminutio
. Diseases of the heart and thoracic aorta. s which have been advocated, possibly hold true. Space does notpermit me to consider the arguments for and against these various theories indetail. Those readers who are interested in the subject should consult thewritings, more especially of Drs Barr and Sansom, where they will find fulldetails.—(See articles in the Medical Times and Gazette of January and February1877, and in the Liverpool Medico-Chirii7gical yourJial, July 1882, by Dr Barr ;and Diagnosis of Diseases of the Heart, by Dr Sansom, p. io5, et seq.) ^ Asynchronism, without any diminution in the duration of the mitral andtricuspid first sounds, might account for the condition, if the duration of thewhole cardiac revolution [ of the diastolic portion of the revolution) was muchincreased ; if, for example, the heart were contracting 30 instead of 72 times in aminute, 158 Diseases of the Heart. occupies (roughly) jV^hs of the entire cardiac revolution. (Seefig- 39-) Now, granting that the tricuspid first sound— as is. Fig. 39.—Uiagmmmatic representation of the cardiac = first or short or long silence. probably the case—is of somewhat shorter duration thanthe mitral first sound, say that it occupies xV^^^ ^^ ^^^entire cardiac revolution, it is almost impossible to conceivethat reduplication could be produced by asynchronism alone,that is to say, that reduplication could occur in any case inwhich the mitral and tricuspid first sounds and the wholecardiac cycle (the cycle for both the right and the lefthearts) preserved their normal length. For if such were thecase, joths + jo^hs, iiyths of the entire cardiac revolu-tion, would be occupied by the reduplicated first sound,and to this we must add the interval which is required, must separate the two component elements of thereduplicated sound, in order that each element may be per-ceived as a separate and distinct sound by the ear. Furthe
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectheart, bookyear1884
