Comparison of echocardiography and radiology in the diagnosis of aortic root dilatation in Marfan's syndrome and in syphilis.

Aortic root dilatation was sought by echocardiography and radiology in 500 consecutive patients referred to an echocardiography laboratory from cardiac or medical clinics and wards. Forty-four of these patients (8.8%) had false echocardiographic evidence of aortic root dissection, but no clinical evidence of the disease. These false findings were attributed to the changing of the transducer angulation, post-stenotic dilatation, calcific aortic stenosis, generalised arteriosclerosis, and thin reverberations behind the posterior wall echo. In one patient with Marfan's syndrome, the chest radiograph was normal and a diagnosis was established by echocardiography. In another patient with syphilis, the dilatation was seen in the chest radiograph while echocardiography revealed a normal proximal aorta. In syphilis the dilatation begins distally and because of the intervening lung tissue echocardiography is unhelpful. Echocardiograms easily detect the aortic valve ring while radiographs show the more distal ascending aorta. These observations may be of added value in the diagnosis of aortic root disease.