Criteria for and against primary correction of Fallot's tetralogy.

The operability of tetralogy of Fallot (TOF) depends on the development of the pulmonary arteries which must be large enough to accomodate the post-repair blood flow. In contrast to later in life, this is not always true during the first 2 years. In the presence of an urgent surgical indication, therefore, the decision must be made whether to opt for primary correction or palliation. While palliation is unavoidable in patients with hypoplastic pulmonary arteries, the surgeon may choose this operation even in the presence of favorable anatomical conditions, as a result of personal experience. From 1978 through December, 1983 primary intracardiac correction of TOF was performed in 46 children, aged 4 months to 2 years (mean 13.1 months) in our clinic. Twenty-two (48%) were infants under the age of one year. Indications for operation were clinically derived from hypoxic spells or severe persistent hypoxemia. Amongst the diagnostic measures, angiographic delineation of both pulmonary arteries and the descending aorta was most important. A relationship of the diameter of the aorta (at diaphragmatic level) to the sum of the right and left pulmonary arteries: Ao.desc./(R + LPA) less than or equal to 0.6 indicated pulmonary arteries of sufficient size for primary correction, while higher values commanded palliative surgery.(ABSTRACT TRUNCATED AT 250 WORDS)