Laboratory tests

ECG () at 22 years of age showed normal sinus rhythm with no signs of overload, and normal ventricular repolarization. PA = +10º , QRSA = +50º , TA = +50º (lower tracing). ECG prior to operation, at 10 months of age (upper tracing), showed marked left ventricular overload, with QRSA = +70º , PA = +20º and TA = +80º ; RS morphology (amplitudes of 24 and 30 mm) from V1 to V3 and QRs (amplitudes of 10, 50 and 3 mm) from V4 to V6; Sokolow index of 90 mm; no ventricular repolarization abnormalities.

Chest radiograph showed normal cardiac silhouette (cardiothoracic ratio = 0.46) and pulmonary vasculature (). In the image prior to surgery, these parameters were markedly increased, with a cardiothoracic ratio of 0.85 ().

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