Univentricular heart: can we alter the natural history?

Surgical treatment must be considered for patients with univentricular heart in view of their poor natural history. Since one of the major factors influencing the natural history of this malformation is the amount of pulmonary blood flow, we discuss the potential surgical options by separately considering the two main pathophysiological situations: univentricular heart with restricted pulmonary blood flow, and univentricular heart with unrestricted pulmonary blood flow. We have reviewed the early and late results of surgical treatment based on our experience with 19 patients and the data from the literature. Temporary relief of symptoms can be provided by palliative operations (systemic-pulmonary shunt, atrioseptectomy, enlargement of the outlet foramen, pulmonary artery banding, or palliative Mustard or Senning procedure). "Corrective" surgery, by means of either a modified Fontan operation or ventricular septation, carries a high early mortality (about 30%) and a high early and late morbidity, with only 50% of survivors enjoying an asymptomatic life. Studies of the long-term efficacy of palliative operations as well as our experience and that of others with "corrective" operations, which have a relatively short follow-up, do not yet indicate whether presently available surgical procedures can alter the natural history of patients with univentricular heart.