Response to isoproterenol infusion in pediatric patients following atrial repair of transposition of the great arteries.
The postoperative function of the right (systemic) ventricle (SV) was evaluated in eight pediatric patients who had undergone intra-atrial switching for simple transposition of the great arteries (TGA). SV function was evaluated at rest and during isoproterenol (ISP) infusion and compared with left ventricular function in the control group. The control group consisted of five patients including two with postoperative pulmonary stenosis, two with mild pulmonary stenosis and one with postoperative partial anomalous pulmonary venous drainage. SV-graphy was performed at rest. During ISP infusion, the TGA group showed a significant increase in cardiac index (3.50 +/- 0.68 (mean +/- SD) L/min/m2 to 4.94 +/- 1.53 L/min/m2, p less than 0.05) and no significant changes in stroke volume index (SVI). Similar changes were observed in the control group. Resting SV ejection fraction was 0.37 +/- 0.05 in the TGA group. In regard to the relationship between SV end-diastolic pressure and SVI, all but one of the TGA patients showed normal response to the stress. These results indicated that the right ventricle in TGA showed an acceptable response to ISP stress and acted as a systemic ventricle for at least two years after surgery.
D002675:Child, Preschool; D006352:Heart Ventricles / Q000187:drug effects; D006801:Humans; D007223:Infant; D007545:Isoproterenol / Q000494:pharmacology*; D009200:Myocardial Contraction; D005082:Physical Exertion; D011184:Postoperative Period; D012146:Rest; D013318:Stroke Volume; D014188:Transposition of Great Vessels / Q000601:surgery*; D016276:Ventricular Function
D007545:Isoproterenol