Hypoplastic left heart syndrome

Overview

Board takeaway: Plan dental care from the child’s current single-ventricle physiology, repair stage, medications, and cardiology instructions.

What is hypoplastic left heart syndrome?

The left ventricle, mitral or aortic valves, and ascending aorta are variably underdeveloped. The left heart cannot support normal systemic output. Ductal closure after birth can precipitate severe deterioration, making this a critical congenital defect.

How is hypoplastic left heart syndrome treated?

Prostaglandin support maintains ductal patency initially. Staged palliation commonly includes a Norwood, bidirectional Glenn, and Fontan pathway, with timing individualized by the cardiac team. The right ventricle supports systemic circulation and systemic venous blood is directed toward the lungs. Transplantation is an alternative for selected patients; neither strategy removes lifelong follow-up needs.

What oral risks occur in children with hypoplastic left heart syndrome?

Feeding difficulty, medically necessary calorie supplements, medication-related dry mouth or gingival enlargement, and barriers to hygiene can increase disease burden. Prior hospitalizations or intubation may affect development and the airway. Antithrombotic or transplant-related medications change bleeding or infection planning.

How should dental treatment be planned for hypoplastic left heart syndrome?

1. Clarify current physiology: procedure stage, baseline saturation, ventricular function, symptoms, rhythm, and exercise tolerance.
2. Coordinate with cardiology: determine tolerable procedures, monitoring, anesthesia setting, and medication plans.
3. Prevent and treat infection: avoid unnecessary delay in addressing dental disease before planned cardiac intervention.
4. Plan hemostasis: coordinate any antithrombotic therapy rather than stopping it independently.
5. Confirm endocarditis prophylaxis: many children have qualifying cyanotic disease or palliative shunts or conduits, but document the specific indication and procedure.

What changes dental risk after Fontan palliation or transplantation?

Fontan-related hemodynamic limitations, arrhythmia, thrombosis, liver disease, or ventricular dysfunction can change the plan. Transplant recipients require assessment of immune suppression, infection, drug effects, and cardiac valvulopathy. New cyanosis, poor perfusion, or respiratory distress requires urgent medical review; elective treatment waits for stability.

Exam pearl

Sources

• Supplemental study guide: Hypoplastic left heart syndrome
• AAPD: Management of Dental Patients with Special Health Care Needs (2026)
• CDC: Hypoplastic Left Heart Syndrome
• AAPD: Antibiotic Prophylaxis for Dental Patients at Risk for Infection (2026)
• AAPD: Dental Management During Immunosuppressive Therapy and Head and Neck Radiation (2026)