Myocarditis in Minnehaha County, South Dakota, 1880-1939

Area of Science:

• Cardiovascular Pathology
• Medical History
• Epidemiology

Background:

• An observed increase in myocarditis diagnoses occurred in Minnehaha County between 1920 and 1940.
• This trend included both fatal and chronic myocarditis cases.

Purpose of the Study:

• To investigate the cause of the apparent increase in myocarditis incidence in Minnehaha County during the specified period.
• To determine if the observed rise reflected actual disease prevalence or diagnostic practices.

Main Methods:

• Analysis of interment records from Mt. Pleasant Cemetery.
• Word frequency studies in two major American medical journals.
• Review of related medical publications from the era.

Main Results:

• No evidence suggests a genuine increase in inflammatory myocardial disorders in Minnehaha County.
• The observed increase in myocarditis diagnoses appears to stem from physician diagnostic choices.
• Local diagnostic terminology was not aligned with contemporary clinical and pathophysiologic literature.

Conclusions:

• The apparent rise in myocarditis incidence was an artifact of diagnostic terminology, not an epidemiological event.
• Physician discretion in applying diagnostic terms influenced the recorded frequency of myocarditis.
• Historical medical records require careful interpretation regarding diagnostic trends.