Diphtheritic cardiomyopathy

This code represents heart muscle damage (cardiomyopathy) specifically caused by the toxins produced during a diphtheria infection. It signifies a serious cardiac complication directly attributable to the bacterial disease, often manifesting as myocarditis, heart failure, or arrhythmias.

Use this code when documentation clearly links cardiomyopathy to a confirmed or suspected diphtheria infection. This typically occurs in patients presenting with cardiac symptoms following a diagnosis of diphtheria, or when diphtheria is identified as the underlying etiology of a newly diagnosed cardiomyopathy.

• Always code the underlying diphtheria infection first (A36.x) as the primary diagnosis, followed by this code.
• Ensure documentation specifies "diphtheritic" or "due to diphtheria" to support the causal link.
• Do not use for cardiomyopathy from other infectious causes; those have specific codes.