Erin Petkau was born at Morden District General Hospital on December 17, 1994, at 0706 hours. The child of Walter and Barbara Petkau, she was born at 41 weeks gestation and weighed only 2,610 grams.

On December 18, after Erin had cyanotic spells and a heart murmur was detected, she was transferred to the HSC. On admission to the HSC at 2007 hours, her colour was pink and her oxygen saturation was good. She was also noted to have good femoral pulses and peripheral perfusion.

Tests conducted on December 18 and 19 identified:

• Tetralogy of Fallot with a marked aortic override above a large ventricular septal defect and right ventricular hypertrophy
• either an atrial septal defect or a patent foramen ovale
• severe pulmonary valve stenosis
• small pulmonary arteries
• a patent ductus arteriosus.

Erin's aorta was positioned over the top of the ventricular septum (and thus termed an 'overriding aorta'), rather than being attached to the left ventricle. She had a large hole in the septal wall separating the ventricles. In addition, her ductus arteriosus was open and she had either an atrial septal defect or a patent foramen ovale, linking her atrial chambers.

Healthy heart

Diagram 8.9 Erin Petkau - pre-operative heart 1 - Atrial septal defect 2 - Severe pulmonary valve stenosis 3 - Right ventricular hypertrophy 4 - Patent ductus arteriosus 5 - Ventricular septal defect with overriding aorta 6 - Right ventricular outflow tract obstruction

Erin was treated with antibiotics for a possible infection. Dr. Soni saw her at 0400 hours and performed an echocardiogram. Soni assessed Erin as a pink Tetralogy of Fallot and recommended treatment with prostaglandin if there was a decrease in oxygen saturation. Giddins concurred with this assessment and indicated that surgery to insert a shunt was required. According to Barbara Petkau, Soni told the family that Erin would likely need surgery within one or two weeks.