Late results of palliative atrial switch for transposition, ventricular septal defect, and pulmonary vascular obstructive disease

Background. Palliative atrial switch (PAS) procedures that reroute pulmonary and systemic venous drainage and leave a ventricular septal defect (VSD) open have been used in the treatment of deeply cyanotic patients who have severe pulmonary vascular obstructive disease (PVOD). Palliative atrial switch is beneficial for patients with transposition of the great arteries or other complex lesions with VSD who show higher arterial oxygen saturation in the pulmonary artery than in the aorta (transposition hemodynamics/unfavorable streaming). We reviewed the early and late results of PAS (Mustard, n = 25; Senning, n = 3) in patients at two institutions. Methods. Between April 1965 and March 2000, PAS was performed in 28 cyanotic patients (18 male, 10 female). Median age was 10 years (range, 1 to 27). Mean preoperative pulmonary arterial pressure was 68 mm Hg (range, 30 to 121 mm Hg). Mean systemic arterial oxygen saturation was 65% (range, 47% to 80%). The majority of patients (95%) were in New York Heart Association (NYHA) functional class III or IV preoperatively. Results. Overall early mortality was 21%; for patients after 1972 (n = 23), the early mortality was 8.7%. Mean follow-up was 8.3 years (maximum 20). Mean postoperative systemic arterial oxygen saturation was increased significantly to 88% (p < 0.0001). Late survival for early survivors at 5, 10, and 15 years respectively was 84% (59%, 97%), 64% (39%, 88%), and 54% (15%, 72%). The NYHA functional class was significantly improved; 94% of late survivors (n = 17) were in functional class I or II (p = 0.002). Conclusions. The PAS operation significantly improves systemic arterial oxygen saturation and quality of life in selected patients with transposition hemodynamics, VSD, and severe PVOD.