Dextrocardia and isolated laevocardia. II. Situs inversus and isolated dextrocardia.

Recently, we have reported 20 cases of isolated 1lvocardia (Campbell and Deuchar, 1965), and here we are describing 33 cases of dextrocardia with malformations of the heart. These are nearly always present when the heart is on the right side without inversion of the abdominal viscera (isolated dextrocardia), as they are with isolated levocardia: generally they produce a right-to-left shunt and the patient is cyanotic. Complete situs inversus, on the other hand, is most often found incidentally in a subject whose heart is normal in every other way, but its presence does not exclude the occurrence of other malformations. Among any large group of patients with malformations of the heart, there will be some with situs inversus, and the proportion of 0-8 per cent shown in Table I is so much above that found in the general population that situs inversus must be associated with some extra liability to other malformations of the heart. The proportion so affected, one in each four or five (Campbell, 1963), is much greater than has generally been supposed. Among our first 670 patients with cyanotic congenital heart disease (1947-53), the proportion with situs inversus is 1 per cent (Table I) and the proportion with isolated dextrocardia is larger (288%). The corresponding proportion among patients with acyanotic congenital heart disease (CHD) is much less, 0 4 per cent. Berri (1958) found a similar proportion with dextrocardias (2.2%) among 2695 patients with congenital heart disease in the service of the Hopital de Ninios de Buenos Aires. Since then (1953) we have seen 5 other examples, making 33 in all, but do not know the number of patients with CHD from which they were selected. The sex and age distribution of these 33 with dextrocardia are shown at the bottom of Table I. There were about equal numbers of each sex. Nearly 80 per cent were under 10 years when first seen and