Tetralogy of Fallot With Pulmonary Atresia Clinical Presentation

Updated: Dec 22, 2020
  • Author: Michael D Pettersen, MD; Chief Editor: Howard S Weber, MD, FSCAI  more...
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History and Physical Examination

Clinical presentation in tetralogy of Fallot with pulmonary atresia (TOF-PA) depends on the source and volume of pulmonary blood flow. This usually occurs via the ductus arteriosus and/or aortopulmonary collaterals.

Infants and older children

The newborn infant, in whom the ductus arteriosus is the sole source of pulmonary blood flow, is often symptomatic within the first hours to days of life and becomes increasingly cyanotic as the ductus closes. In the presence of significant aortopulmonary collaterals, cyanosis may be absent. If adequate collaterals or additional sources of pulmonary blood flow are lacking, closure of the ductus may produce hypoxemia too severe for survival. Thus, early recognition of the diagnosis along with prompt institution of prostaglandin E1 (PGE1) infusion is life saving in this instance.

Conversely, when the aortopulmonary collaterals constitute the only source of pulmonary blood flow, the clinical presentation may vary from cyanosis with inadequate pulmonary blood flow to no cyanosis with increased pulmonary blood flow. Uncommonly, pulmonary blood flow is sufficiently increased to cause symptoms due to pulmonary overcirculation (poor feeding, excessive sweating, rapid breathing).

Older infants and children commonly present with cyanosis as the child outgrows the source(s) of pulmonary blood flow. The presence and degree of cyanosis depends on the adequacy of pulmonary blood flow and may range from none to severe. Peripheral pulses are normal in most patients, but they may be bounding in patients with exuberant pulmonary blood flow.

On rare occasions, patients with well-developed aortopulmonary collaterals or persistent patency of the ductus arteriosus may present with heart failure. Symptoms develop several weeks after birth as pulmonary vascular resistance (PVR) decreases and pulmonary blood flow increases.

Peripheral pulses and blood pressures are usually normal during the first few days of life. Patients with increased pulmonary blood flow may be noted to have bounding pulses.

Auscultation reveals a normal first heart sound with a single second heart sound. A systolic murmur may be audible along the lower left sternal border. Because the right ventricular outflow tract is atretic, there is no separate loud systolic ejection murmur at the upper left sternal border that is typical of the usual form of tetralogy of Fallot. If a patent ductus arteriosus is present, a continuous murmur usually is heard after the first 4-6 weeks of life. If systemic-to-pulmonary collateral vessels are present, continuous murmurs can be heard over the back or in the axillae.

Patients with palliative surgical history

Patients who have undergone palliative surgical procedures may also present with variable symptomatology. Most palliative procedures are intended to augment pulmonary blood flow and improve growth of the central branch pulmonary arteries by placement of a systemic-to-pulmonary artery shunt. These shunts may distort the pulmonary vasculature, resulting in branch pulmonary artery stenosis, or they may cause stenosis.

Pulmonary artery hypertension and elevated pulmonary vascular resistance has been noted in the presence of large systemic-to-pulmonary connections. This problem was prevalent with the Waterston (direct anastomosis of the ascending aorta to the pulmonary artery) and the Potts (direct anastomosis of the descending aorta to the pulmonary artery) shunts, both of which have been largely abandoned.