Summary: Subaortic stenosis has been described with increasing frequency as an ominous feature of atrioventricular septal defect (AVSD), especially following surgical correction of the anomaly in non-Down's syndrome patients. In order to study the surgical anatomy of the left ventricular outflow tract in this malformation, 48 hearts featuring AVSD were examined. Obstructive lesions wcre classified into unequivocal forms (class A, 13.5%) and potential ones (class B, 10.8%). In the remaining hearts (class C, 75.7%) no obstruction was noted. In class A, subaortic stenosis was due to exaggeration of the anticipated anomalous arrangement of atrioventricular valve tensor apparatus, to the persistence of a subaortic muscular infundibulum, and to a discrete fibrous diaphragm. A potential for subaortic stenosis is provided by the unwedged position of the aortic valve. The left ventricular outflow tract is transformed into a long, forward-displaced fibromuscular channel. Morphometric analysis showed in AVSD (with both common annulus and separate orifices) a significantly (p

Abstract

The known species of the flea beetle genus Collartaltica Bechyné, endemic to the Afrotropical Region, are revised. A brief diagnosis of the genus is given and two new species, C. meridionalis sp.n. and C. alluaudi sp.n., respectively from the Southern Africa and Kenya, are described. Line drawings of male and female genitalia and scanning electron micrographs of particular morphological aspects of the species considered are also included. Finally, a cladistic analysis of this genus using maximum parsimony is presented.

No abstract

No abstract