Right ventricular to pulmonary artery conduit instead of modified Blalock-Taussig shunt improves postoperative hemodynamics in newborns after the Norwood operation.
OBJECTIVE
Perioperative mortality, prolonged postoperative recovery after the Norwood procedure, and mortality between stage I and stage II might be related to shunt physiology. A right ventricular to pulmonary artery conduit offers a banded physiology in contrast to a Blalock-Taussig shunt. The purpose of this study was to assess the hemodynamic differences and their consequences in the postoperative course between Norwood patients with a Blalock-Taussig shunt and those with a right ventricular to pulmonary artery conduit.


METHODS
From October 1999 until May 2002, 32 unselected consecutive patients underwent a Norwood procedure at the General Hospital Linz. The first 18 patients received a Blalock-Taussig shunt. In the remaining 14 patients we performed a right ventricular to pulmonary artery conduit. Both groups were compared.


RESULTS
The diastolic blood pressure was significantly higher in the right ventricular to pulmonary artery conduit group (P <.001). Despite a higher FIO(2), PO(2) levels tended to be lower in the first 5 postoperative days. At the age of 3 months, catheterization laboratory data showed a lower Qp/Qs ratio in the same group (0.86 [0.78; 1] versus 1.55 [1.15; 1.6]; P =.005) and a higher dp/dt (955 [773; 1110] vs 776 [615; 907]; P =.018). (Descriptive data reflect medians and quartiles [in brackets].) Hospital survival was 72% in the Blalock-Taussig shunt group versus 93% in the right ventricular to pulmonary artery conduit group. Mortality between stage I and stage II was 23% in the Blalock-Taussig shunt group versus 0% in the right ventricular to pulmonary artery conduit group.


CONCLUSIONS
A higher diastolic blood pressure and a lower Qp/Qs ratio were associated with a more stable and efficient circulation in patients with a right ventricular to pulmonary artery conduit. More intensive ventilatory support was necessary during the first postoperative days. We did not note any adverse effects of the ventriculotomy on ventricular performance.
Mair
Rudolf
R
Department of Cardiac Surgery, General Hospital Linz, Austria. rudolf.mair@akh.linz.at
Tulzer
Gerald
G
Sames
Eva
E
Gitter
Roland
R
Lechner
Evelyn
E
Steiner
Jürgen
J
Hofer
Anna
A
Geiselseder
Gertraud
G
Gross
Christoph
C
D000714:Anastomosis, Surgical / Q000379:methods; D006348:Cardiac Surgical Procedures / Q000379:methods* / Q000401:mortality; D005260:Female; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D006352:Heart Ventricles / Q000601:surgery; D006439:Hemodynamics; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D007231:Infant, Newborn; D008297:Male; D011183:Postoperative Complications / Q000517:prevention & control; D011336:Probability; D011379:Prognosis; D011651:Pulmonary Artery / Q000601:surgery; D012189:Retrospective Studies; D018570:Risk Assessment; D012494:Sampling Studies; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D016896:Treatment Outcome