Association between cardiac atrioventricular conduction and antibodies to Chlamydia pneumoniae in fibromyalgia patients.

This study supports the hypothesis of an association between atrioventricular conduction and antibodies to Chlamydia pneumoniae in fibromyalgia patients. It suggests that the higher the level of such antibodies, the greater the electrocardiographic PR interval, and therefore the slower the atrioventricular conduction. Potential pathophysiological mechanisms include a chronic inflammatory response to Chlamydia pneumoniae and the action of the bacterial lipopolysaccharide. The latter may involve stimulators of interferon genes, activation of the cardiac NOD-like receptor protein 3 inflammasomes, and downregulation of fibroblast growth factor 5 in the heart.