[Single ventricle. II. Clinical study. Special studies and surgical treatment]

A study was made of 29 cases of single ventricle confirmed by autopsy, hemodynamic study, or both. It must be emphasized that the term single ventricle excludes whatever malformation which shows traces of an intraventricular septum. Thus conceived, the malformation has been seen to have different clinical courses, which only permit partial diagnosis that may suggest the possibility of "single ventricle". In live patients this can only be diagnosed with specialized studies. In outline, there exist 4 types of clinical hemodynamic behavior: 1) The type with marked increase of pulmonary flow, in which the single cavity vascular systems, pulmonary and aortic, had similar pressures. This type behaves, in a certain way, like large interventricular communications. 2) The type which behaves hemodynamically like a large hypertensive communication with delayed cyanosis of rapid evolution and with few manifestations of heart failure. 3) The third type also has pulmonary hypertension with delayed cyanosis. This differs from the preceeding in that there is a preferential flow in such a way that the venous blood proceeding from the right atrium empties into the aorta and the arterial blood from the left atrium empties into the pulmonary artery. 4) The fourth type is characterized by rapid cyanosis and from the anatomical point of view has stenosis or atresia of the pulmonary artery. An analysis was made of the varieties which within these four classes actually ocurred or cases which were present as theoretical possibilities: single ventricle with crossed great arteries; single ventricle with transposition of the great arteries; single ventricle with partial distortion of the great arteries; single ventricle with common trunc. A detailed analysis was made of the clinical, hemodynamic, electrocardiographic, and radiological manifestations which are seen in these combinations and an anatomic-embriologic classification is proposed on the basis of the systematization of the 29 cases of the present study. Finally brief considerations are made of the operability of those cases of single ventricle according to their anatomic variety.