Congenital Heart Disease (CHD) is the most common congenital malformation in children and the leading cause of death from birth defects in infancy. Preoperative anxiety is prevalent in children with CHD, but current preoperative care mainly focuses on physical preparation, with insufficient attention to psychological stress, and conventional intervention measures have limitations. As a non-pharmacological method, therapeutic play has been proven effective in relieving children's anxiety, but randomized controlled trials (RCTs) of therapeutic play for preoperative anxiety in children with CHD are still lacking in China. This study adopts a randomized controlled design, in which children with CHD before surgery are randomly divided into the experimental group and the control group. The experimental group receives therapeutic play (including parents' participation, with intervention content designed according to children's cognitive characteristics), while the control group receives routine preoperative nursing. The effect of therapeutic play on relieving preoperative anxiety in children with CHD will be evaluated multi-dimensionally through anxiety scale scores, vital signs, and salivary cortisol levels, providing scientific evidence for clinical intervention of preoperative anxiety in children with CHD.

Inclusion Criteria:

Children diagnosed with congenital heart disease via clinical and imaging examinations, scheduled for elective cardiac surgery (e.g., open-heart surgery under cardiopulmonary bypass, open chest device closure, or percutaneous interventional treatment).

• Aged 0 to 12 years old, with basic communication and comprehension abilities to respond to play interventions and complete anxiety scale assessments.
• Clear consciousness, no severe intellectual, hearing, or speech communication disorders, or pervasive developmental disorders (e.g., autism), and being able to interact with researchers.
• Primary caregivers (father or mother) provide written informed consent and have the ability to understand the study and assist the child with the intervention.

Exclusion Criteria:

• Children with complex critical CHD requiring emergency surgery or admission to the intensive care unit (ICU) upon hospitalization.
• Children with severe neurological disorders (e.g., cerebral palsy, epilepsy), severe hepatic/renal insufficiency, or other major congenital diseases that may affect psychological status or perioperative progress.
• Children who have taken sedatives, anxiolytics, or antidepressants long-term preoperatively, whose anxiety levels have been altered by medication.
• Participants who cannot complete the intervention or outcome assessments for any reason (e.g., surgery cancellation, withdrawal of consent).

Individual participant data (IPD) will not be shared publicly due to patient privacy and confidentiality requirements.