Persistence of the left superior caval vein: can it potentiate obstructivelesions of the left ventricle?

Recent evidence has suggested that persistence of the left superior caval v ein is associated with a high incidence of obstructive lesions of the left heart. To shed more light on this issue 1085 patients with congenital heart disease were studied retrospectively, with the aim of estimating the preva lence of a persistent left superior caval vein and its associated anomalies , focusing attention on obstructive lesions in the left and right ventricle s. Patients with isomerism of the atrial appendages, or hypoplastic left he art syndrome, were excluded. A persisting left superior caval vein was pres ent in 57 patients (5.2%). The overall incidence of obstructive lesions of the left heart was higher in patients with than in those without a persiste nt left superior caval vein (31.6 versus 7.8%, p < 0.001). Relative hypopla sia of the left ventricle was also higher in patients with persistent left superior caval vein (14 versus 0.8%, p < 0.001). The obstructive lesions fo und in the left heart, compared with the number in those without a left cav al vein, were: mitral stenosis, 5.2 versus 0.7%; subaortic stenosis, 5.3 ve rsus 6.9%; aortic coarctation, 17.5 versus 5.8% (p < 0.01); all of these in association, 3.5 versus 0.4%. In contrast, the incidence of obstructive le sions of the right heart was similar in the two groups of patients. It is c oncluded that persistence of the left superior caval vein can perturb the n ormal development of the left ventricle, being strongly associated with obs tructions to left ventricular inflow and outflow.