Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
These concerns need timely assessment but are not always emergencies.
Seek emergency care for severe trouble breathing, blue or gray lips or skin, collapse, inability to wake normally, or a sudden major decline in responsiveness.
Follow any emergency plan provided by the congenital heart team.
Contact the clinical team promptly for worsening feeding, new sweating with feeds, poor weight gain, increasing breathlessness, swelling, fewer wet diapers, unusual sleepiness, fever after a recent procedure, or redness and drainage from a surgical wound.
Regular congenital cardiology follow-up remains important after a successful repair.
The cardiologist will check growth, blood pressure, heart sounds, exercise tolerance, and oxygen level.
Echocardiograms may be used to look for a residual opening, narrowing near the repair, pressure in the lung arteries, or changes in heart function.
Some people need only periodic routine visits after a complete repair, while those with residual problems or pulmonary hypertension need closer monitoring.
Children should transition to an adult congenital heart disease specialist as they reach adulthood rather than relying only on general adult cardiac care.
The article also says
The schedule varies according to the repair and the presence of other heart defects.
The care team can advise about physical activity.
Many people with a fully repaired defect and normal heart and lung pressures can participate in ordinary activities.
Restrictions may be needed when there is pulmonary hypertension, vessel narrowing, abnormal heart function, or another heart condition.
Every sign above is quoted from the sofidex article on Aortopulmonary window. If you are not sure, err upward — it is always reasonable to be checked.