Objective: To determine whether one and one half ventricular repair (1.5 VR) is definitely superior to the Fontan procedure in patients having hypoplastic right ventricle (RV) in the setting of pulmonary atresia with intact ventricular septum (PA/IVS) or its relatives, in terms of results in the longer term.
Method: Since 1987, 1.5 VR has been chosen in seven patients with PA/IVS and in six having PS with hypoplastic RV. On preoperative catheterization, right ventricular end-diastolic volume (RVEDV) was 47+/-23% of the anticipated normal value, and annular diameter of the tricuspid valve (TVD) 72+/-22% of normal (Z value being -2.4+/-2.1). Follow-up term was 3-15 (10+/-4) years.
Results: All patients survived 1.5 VR, but one patient died of arrhythmia 9 years later. Freedom from arrhythmia was 80 and 20% at 10 and 12 years, respectively. Two patients have undergone conversion to the Fontan circulation, but none to true biventricular physiology. Consecutive catheterization (1, 5, and 10 years after 1.5 VR) demonstrated no changes in %RVEDV or %TVD. Cardiac index was 2.4+/-0.6 l/min per m(2) at either 5 or 10 years. RA pressure was 9+/-3 and 12+/-2 mmHg at 5 and 10 years, respectively. Smaller %RVEDV and %TVD were associated with episodes of atrial arrhythmia and higher RA pressure. Exercise testing showed anaerobic threshold of 16.6+/-3.4 ml/kg per min and 13.1+/-2.7 ml/kg per min at 5 and 10 years, respectively. These values were equivalent to those in patients with classical tricuspid atresia or PA/IVS undergoing the Fontan procedure, and unequivocally inferior to those in patients having PA/IVS. who could have undergone biventricular repair.
Conclusion: Although we previously expected reasonable functional results after 1.5 VR between the Fontan circulation and biventricular physiology, this was not always the case in patients having pulmonary atresia or stenosis with intact ventricular septum.