Myocardial infarction associated with Chlamydia pneumoniae.

Area of Science:

• Cardiology
• Infectious Diseases
• Pathology

Background:

• Myocardial infarction (MI) is rare in black South Africans, despite hypertension being common.
• Coronary heart disease (CHD) has been associated with Chlamydia pneumoniae infection.

Purpose of the Study:

• To investigate the potential role of Chlamydia pneumoniae in a rare case of MI in a black South African man.
• To identify the presence and location of C. pneumoniae within the coronary artery lesion and surrounding tissue.

Main Methods:

• Serological testing for C. pneumoniae infection.
• Immunocytochemical, electron microscopy, and polymerase chain reaction (PCR) techniques to detect C. pneumoniae in atherosclerotic plaque.
• Histological examination of the coronary artery and myocardium.

Main Results:

• Chlamydia pneumoniae was identified within the ruptured atherosclerotic plaque in the left anterior descending coronary artery.
• The organism was detected in smooth-muscle cells, foam cells, and interstitially within the plaque.
• C. pneumoniae DNA was also found in the myocardium of the left ventricle at the infarct site.

Conclusions:

• The findings support a strong association between Chlamydia pneumoniae infection and coronary heart disease (CHD).
• This is the first study to identify C. pneumoniae within a ruptured plaque directly causing a myocardial infarction (MI).
• The presence of C. pneumoniae in the infarct area suggests a potential role in the pathogenesis of MI.