Norwood procedure
| Norwood procedure | |
|---|---|
Diagram of a healthy heart and one with Hypoplastic left heart syndrome. In the heart on the right, note the near absence of the left ventricle, which normally provides systemic circulation. Following the three-stage palliation (Norwood, Glenn or hemi-Fontan, then Fontan), blood flow from the right ventricle is rerouted to serve this function, which means that an alternative source of pulmonary circulation must be provided. | |
| ICD-9-CM | 35.8 |
The Norwood procedure is the first of three palliative surgeries for patients with hypoplastic left heart syndrome (HLHS) and other complex heart defects with single ventricle physiology intended to create a new functional single ventricle system. The first successful Norwood procedure involving the use of a cardiopulmonary bypass was reported by Dr. William Imon Norwood, Jr. and colleagues in 1981.
Variations of the Norwood procedure, or Stage 1 palliation, have been proposed and adopted over the last 30 years; however, its basic components have remained unchanged. The purpose of the procedure is to utilize the right ventricle as the main chamber pumping blood to the body and lungs. A connection between left and right atria (collecting chambers of the heart) is established via atrial septectomy, allowing blood arriving from the lungs to travel to the right ventricle. Next a connection between the right ventricle and aorta is created using a tissue graft from the main pulmonary artery. Lastly, an aortopulmonary shunt is created to provide blood flow to the lungs from the systemic circulation. The most common shunts are the Modified Blalock Taussig shunt (MBTS) or right ventricle- to pulmonary artery shunt (RVPA or Sano shunt).
Most patients who undergo a Norwood procedure will proceed to further stages of single ventricle palliation. A second surgery, also known as the Glenn procedure, occurs at 4–6 months of age. The third surgery is the Fontan procedure, occurring when patients are 3–5 years of age.