Both of our cases are examples of antecedent giant cell arteritis of the temporal arteries followed five to seven years later by new onset of aortic regurgitation secondary to involvement of the aorta by giant cell arteritis. Giant cell arteritis results in destruction of the elastic fibers of the arterial wall with giant cell reaction. This leads to dilatation and distortion of the aortic valve ring and the aortic root (annuloaortic ectasia). Case 1 is the only case in the literature that has a clear-cut, well-documented giant cell arteritis of the temporal artery leading to a histologically documented aortic giant cell arteritis and resultant severe aortic regurgitation. The giant cell arteritis found in the aortic biopsy specimen was similar to the temporal artery biopsy specimen five years earlier.
Both biopsy specimens revealed similar intimal thickening, disruption of internal elastic lamina, and prominent infiltrate of chronic inflammatory cells in the outer media and serosa. Giant cell infiltrates comprised a prominent component of the infiltrate. This provides strong evidence that these diseases were one and the same process involving different sized vessels.