Periarteritis of coronary arteries with severe eosinophilic infiltration. A new pathologic entity (eosinophilic periarteritis)?

A 40 year-old male presented symptoms of angina pectoris for about nine years and expired with symptoms of unstable angina, changing pattern at the terminal stage. At autopsy, both right and left coronary arteries of the subepicardial region were grayish white and elastic hard. Histologically, inflammatory infiltration was localized in adventitia of coronary arteries located in the subepicardial region. Inflammatory cells infiltrated into the adventitia were mostly eosinophiles. The medial smooth muscle cells were well preserved and the intima showed irregular thickening with fibrosis. Vascular obstruction or recanalization could not be observed. As a result of these findings, it was considered that these inflammatory changes of the coronary arteries could be termed eosinophilic periarteritis. These inflammatory changes could not be found in the intramural coronary arteries. Rather extensive fibrosis could be seen in the muscle layer centering about the posterior wall of the left ventricle. No findings of angiitis could be detected in the blood vessels except subepicardial coronary arteries.