The Annals of Thoracic Surgery, Vol 44, 128-134, Copyright © 1987 by The Society of Thoracic Surgeons
Optimal flow of aorta-pulmonary artery shunt in patients with cyanotic heart disease
K Kusuhara, S Miki, Y Ueda, Y Ohkita, T Tahata and M Komeda
An aorta-pulmonary artery shunt with an expanded polytetrafluoroethylene
(Gore-Tex) tube graft (3 to 6 mm in diameter) was done in 33 cyanotic
patients with complex congenital heart disease. The patients ranged from 14
days to 22 years old. In 28, the shunt flow (QB) was measured, and the
optimal QB and graft size were determined. Nine patients had severe heart
failure because of an excessively large shunt. Seven of these patients
died, 5 early and 2 late after operation. The QBS in these 9 patients were
extremely high; the QB index and the ratio of shunt flow to systemic flow
(QB/QS) were 3.86 +/- 0.91 L/min/m2 (mean +/- standard deviation) and 52.4
+/- 9.7%, respectively. The QB index and the QB/QS of patients without
severe cardiac failure were 1.49 +/- 0.92 L/min/m2 and 27.2 +/- 11.4%,
respectively. In conclusion, the QB index, the QB/QS, or both should be
maintained in the range of 1.6 to 2.4 L/min/m2 and 30 to 40%, respectively.
In infants, however, it is advisable to control the flow at less than the
range just given. Analysis of graft size in relation to body weight (BW, in
kilograms) and body surface area (BSA, in square meters) showed that the
optimal diameter (D, in millimeters) could be calculated by the following
formulas: D = 1.88 In(BW) + 1.8 (r = .86) D = 0.87 In(BSA) + 5.3 (r = .73).
