Pseudotumour formation in atheromatous coronary arteries.

Three cases with mass like lesions (pseudotumours) surrounding atheromatous coronary arteries were referred to the Royal Brompton Hospital for expert pathology review. All were males with mean age 74 years (range 55-91). In all cases, coronial autopsies were carried out for sudden deaths in the community. Past medical histories of note were hypertension (N = 2) and ischaemic heart disease (N = 1), with one patient having a past history of aortic aneurysm repair. At autopsy, firm, white and whorled masses surrounded both right and left coronary arteries ranging in size from 9 to 25 mm in diameter. Each coronary artery had intimal atheroma with associated stenosis ranging from moderate to severe. A thrombus was identified in one case. Histological sections showed a mixed inflammatory infiltrate extending from the media into the adventitia of each coronary artery, composed predominantly of plasma cells and lymphocytes with rare neutrophils and eosinophils. There was accompanying dense fibrosis accounting for approximately 50% of the mass size on microscopic examination of slides. The presence of intimal circumferential atheroma was confirmed in all cases. Immunohistochemical studies showed staining with IgG4 in two of three cases. Atheroma may be associated with mild chronic inflammation present in the intima or associated with plaques and adventitia. The differential diagnosis for coronary artery inflammatory masses would include vasculitis, syphilis, inflammatory pseudotumor and IgG4 associated disease. This is the first report of isolated coronary artery IgG4 related disease in association with atheroma.

Sudden cardiac death caused by coronary vasculitis.

Coronary vasculitis is a rare and diagnostically challenging cause of sudden cardiac death (SCD). There are currently no large-scale series on this rare entity. A retrospective non-case-control observational study of SCD with coronary vasculitis referred to a tertiary cardiac pathology referral centre at the National Heart and Lung Institute at the Royal Brompton Hospital between 1996 and 2010 was completed. Ten cases of SCD with coronary artery vasculitis were retrieved from a database of 1,980 SCD cases (0.5%) with a 1:1 male/female ratio; median age was 39 years and range 15-71 years. Six deaths occurred in hospital following symptoms or cardiac arrest in the community; the remaining died at rest at home (n = 4). Appearances ranged from aneurysms of the coronary artery to occlusive lesions mimicking atheroma or masses imitating tumour. Types of vasculitis detected were: eosinophilic (n = 5), two associated with Churg-Strauss syndrome; lymphoplasmacytic vasculitis (n = 4); and idiopathic giant cell arteritis (n = 1). This study shows coronary vasculitis as a rare cause of SCD with a variable macroscopic and microscopic presentation that pathologists need to be aware of.