Absence of the left pulmonary artery in Fallot's tetralogy

Management of tetralogy of Fallot with unilateral absence of pulmonary artery: an overview

Tetralogy of Fallot with unilateral absence of pulmonary artery (PA) is a rare congenital anomaly that has been reported in isolated case reports and small case series. There is no well-defined treatment algorithm for these patients, and repair has been associated with high mortality, although survival is improving in the more recent era. Recent reports suggest strict case selection criteria based on PA dimensions and size of the left ventricle.

Tetralogy of Fallot with unilateral absent pulmonary artery

BACKGROUND

Tetralogy of Fallot is a common congenital cardiac malformation. A rare subgroup includes unilateral absence of the pulmonary artery, either the left or the right main branch. The literature lacks an established treatment for these cases, and surgical options carry certain mortality and morbidity.

PATIENTS AND METHODS

There were five patients who had single pulmonary artery and received surgical treatment among the 126 patients with the diagnosis of Tetralogy of Fallot, who were admitted to our institution between July, 2010 and November, 2011. All the patients were male. Ages ranged between 12 months and 8 years. The mean body mass index was 17.1 plus or minus 3.4 kilograms per square metre. Pulmonary artery Nakata index, Nakata index Z-score, and the McGoon index were used for the quantitative assessment of the pulmonary artery and to determine the surgical strategy.

RESULTS

Urgent modified Blalock-Taussig shunt operations were performed in two patients with very low oxygen saturation and haemodynamic instability. These patients are scheduled for corrective procedures on an elective basis. There was one patient who received an elective shunt procedure; however, the post-operative course was complicated with the overflow phenomenon and the patient underwent total correction with a check-valved patch used to close the ventricular septal defect. The patient required extracorporeal membrane oxygenator support in the post-operative period. There were two patients who underwent total correction of the pathology uneventfully. Mortality did not occur. Mean durations of hospital stay and follow-up were 14 plus or minus 13.4 days and 184.5 plus or minus 89.3 days, respectively.

CONCLUSION

Our modest series with Tetralogy of Fallot with unilateral absent pulmonary artery indicates the feasibility of surgical correction in patients with appropriate unilateral pulmonary artery size and palliative procedures when the pulmonary artery size is smaller than that predicted for the age. Multi-centre long-term data of larger series are warranted in order to establish a treatment protocol.

Surgical correction of tetralogy of Fallot with unilateral absence of pulmonary artery

BACKGROUND

Tetralogy of Fallot with unilateral absence of the pulmonary artery is a rare congenital heart defect that still represents a surgical challenge. The purpose of this study is to summarize our experience of surgical treatment of this complex lesion.

METHODS

From 1983 to 2003, 27 patients with tetralogy of Fallot and unilateral absence of the left (n = 25) or right (n = 2) pulmonary artery underwent different surgical interventions. The age of patients ranged from 40 days to 37 years (median, 5.3 years). Pulmonary arterial Nakata index and Nakata index Z-score were used for the quantitative assessment of the contralateral pulmonary artery. Twenty patients underwent various palliative procedures, namely Blalock-Taussig or Gore-Tex shunt, transluminal balloon pulmonary valvuloplasty, and reconstruction of right ventricular outflow tract without ventricular septal defect closure. At a median interval of 3.6 years after palliation, 13 patients underwent complete repair of tetralogy of Fallot. In the other 7 patients, complete repair was performed as a primary intervention.

RESULTS

Hospital mortality after palliation and after a complete repair was the same and reached 5%. Sixteen patients with the Nakata index greater than 200 mm2/m2 and Z-score greater than -4 survived after a complete repair. One of 4 patients with Nakata index less than 200 mm2/m2 and Z-score less than -4 died after surgery.

CONCLUSIONS

Majority of patients with tetralogy of Fallot and unilateral absence of the pulmonary artery require palliative intervention as a first step of surgical treatment. Nakata index greater than 200 mm2/m2 and Nakata index Z-score greater than -4 are criteria for a successful complete repair.

Thoracic arterial arch anomalies

Forty-one well-studied thoracic arterial arch anomalies are related to cases previously reported in the literature and presented with simplified drawings in an attempt to provide a workable understanding of these anomalies.

ABSENCE OF A PRIMARY DIVISION OF THE PULMONARY TRUNK. AN ONTOGENETIC THEORY

An ontogenetic theory is proposed to explain the absence of a primary division of the pulmonary trunk on the basis of an error in the septation of the truncus arteriosus, and the two common varieties of the syndrome are discussed in detail. It is suggested that:

Both lateral pulmonary arteries are present in this syndrome, but one of them arises anomalously from the systemic circulation.

The aberrant origin of one lateral pulmonary artery derives from the dorsal shifting of one of the two ridges responsible for the septation of the truncus arteriosus. The sixth arch on the side of the dorsorotated truncal ridge then becomes incorporated into the newly formed ascending aorta.

The combination of tetralogy of Fallot, right aortic arch, and absent left primary pulmonary division results from a single primordial error: a dorsorotation of the left ridge extending throughout the truncoconus.

The initial portion of the aberrant (systemic) pulmonary artery may obliterate postnatally, thus impairing maturation of the terminal portion. This would explain the frequent failure to demonstrate the artery by angiography and, occasionally, at dissection.

Distal ductal origin of the right pulmonary artery: prospective diagnosis and primary repair in infancy

Absence of the proximal segment of the right pulmonary artery was diagnosed by echocardiography in two neonates. In both a right-sided duct communicated with the right pulmonary artery at the hilum of the lung. Successful surgical repair was undertaken at seven months and 10 weeks, respectively

Investigating the small lung: which imaging procedure?

Ventilation and perfusion radionuclide lung scans, using krypton 81m and technetium-99m macroaggregates, were performed together with a variety of other imaging procedures in 18 children aged between 1 week and 13 years in whom radiology had shown a small lung. Radionuclide scans provided an assessment of regional ventilation and perfusion unobtainable by other means, and 4 main categories of disturbed function could be seen in the radiological small lung--namely, absence of ventilation and perfusion, absent perfusion with preserved ventilation, generalised or segmental decreases in ventilation, and perfusion and segmental perfusion defects in areas of decreased ventilation. The clinical history and other imaging procedures, including fluoroscopy and penetrated mediastinal views, enabled a firm diagnosis to be made in each of these 18 patients. In 3 main pulmonary arteries were absent, 2 had lung aplasia, 2 had lobar aplasia, 9 had varying degrees of pulmonary hypoplasia (two with additional sequestrated segments), 1 had lobar emphysema, and 1 had post-infective lung mal-development (MacLeod's syndrome).

Lung tumor in a patient with congenital unilateral hypoplasia of the pulmonary artery

The occurrence of an undifferentiated carcinoma in the affected lung of a cigarette smoker with asymptomatic congenital hypoplasia of the right pulmonary artery is reported.

ABSENT PULMONARY VALVE IN TETRALOGY OF FALLOT: CLINICAL AND ANGIOGRAPHIC CONSIDERATIONS WITH REVIEW OF THE LITERATURE

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Congenital "absence" and anomalous origin of the main pulmonary arteries. Variations of the same congenital defect

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Right-sided aorta. I. Occurrence of right aortic arch in various types of congenital heart disease. II. Right aortic arch, right descending aorta, and associated anomalies

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Agenesis of Lung

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The aorta and pulmonary arteries in Fallot's tetralogy

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An unusual cause of a continuous murmur simulating persistent ductus arteriosus and associated with other congenital cardiac defects

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