775-5 Increased Incidence of Chlamydia Bacteria Detected within Coronary Arteries of Patients with Atherosclerotic Versus Transplant Induced Coronary Artery Disease

Previous work has suggested an association between Chlamydia pneumoniae infection and coronary atherosclerosis, based on the demonstration of increased serologic titers and the detection of bacteria within atherosclerotic tissue. We sought to strengthen a possible etiologic link by comparing the incidence of Chlamydia infection in coronary atherosclerotic tissue to that in coronary arteries of patients with non-atherosclerotic cardiovascular disease. Coronary tissue specimens obtained from 90 consecutive patients (mean age = 57 yrs) with symptomatic coronary artery disease undergoing directional coronary atherectomy were tested for the presence of Chlamydia species by direct immunofluorescence using mouse monoclonal antibody. Immunofluorescence was positive in 68 (76%), equivocal in 5 (6%) and negative in 19 (21 %) of specimens. Polymerase chain reaction confirmed the specific Chlamydia strain TWAR in 2 cases. No clinical factors except the presence of a primary non-testenotic lesion (odds ratio = 3.0, p = 0.057) predicted the detection of Chlamydia. As a control, coronary tissue specimens from 11 patients with previous cardiac transplantation and subsequent transplant-induced coronary artery disease were also tested. Direct immunofluorescence performed on these diseased coronary artery segments was negative for Chlamydia in every case (p = 0.0001 compared with atherosclerotic specimens). Conclusion This high incidence of Chlamydia detected only in coronary arteries diseased by atherosclerosis suggests an etiologic role for Chlamydia infection in the development of coronary atherosclerosis, which should be further studied.