Tetralogy of Fallot with congenital diaphragmatic hernia with right lung aplasia—a rare entity

Abstract

A combination of tetralogy of Fallot with diaphragmatic hernia represents a very rare entity. We present a case of 18-month-old child presenting late with cyanosis and respiratory distress. Chest X-ray and computed tomography angiography showed tetralogy of Fallot with small left pulmonary artery with right lung aplasia with congenital diaphragmatic hernia with liver and bowel loops in right chest cavity. The patient was managed with central shunt on cardiopulmonary bypass and was discharged uneventfully.

Introduction

The combination of congenital diaphragmatic hernia (CDH) and cardiovascular malformations (CVM) has important clinical and management implications [1].

Tetralogy of Fallot (TOF) is the most common type of cyanotic congenital heart disease with a reported incidence of 0.34 per 1000 live births. The classic tetrad was first described in 1673 anatomist Nicolas Steno, but Étienne-Louis Fallot in 1888 studied the anatomy in detail [2].

TOF is associated with many other congenital defects. CDH, a separate entity itself, has a high morbidity and mortality, caused by delayed or disturbed separation of the thoracic and abdominal compartments of the body. This disturbed separation is caused by closure of embryonic pleuroperitoneal canals effected by growth of the post-hepatic mesenchymal plate and of the pleuroperitoneal folds causing congenital diaphragmatic hernia [3].

Combination of TOF with CDH represents a very rare entity.

Case report

We present an 18-month-old female child, weighing 7.8 kg, who was born by normal vaginal delivery at term by home delivery. The patient had feeding difficulties, with forehead sweating since birth, for which she was shown to a local practitioner and was given antibiotics, but condition remained undiagnosed. The patient was never hospitalised. She had cyanosis since birth, which became severe from the last 2 months and progressively increasing dyspnoea of 2-month duration.

On examination, the patient was cyanosed with baseline room air saturation of 54%. On auscultation, there was no air entry on the right side of the chest with holosystolic murmur at the apex.

Chest X-ray showed situs solitus with rudimentary right bronchus with white out of the right lung area. There was presence of bowel loops in the right chest cavity with oligemia of the left lung area (Fig. 1).

Fig. 1.

Chest X-ray posteroanterior view of the patient with rudimentary right bronchus with bowel loops in the right cavity

Echocardiography showed features of TOF with large sub aortic ventricular septal defect with pulmonary stenosis. In addition, there was absence of right pulmonary artery with associated right lung aplasia. The left pulmonary artery was small and was measuring 5 mm. There was no associated major aortopulmonary collateral.

Computed tomography (CT) angiography confirmed the findings of echocardiography. There was right lung aplasia, with associated diaphragmatic hernia, with herniation of the liver and bowel into the right hemi thorax. The right bronchus was rudimentary. There was presence of bilateral superior vena cava. There was associated TOF with severe pulmonary stenosis with the small left pulmonary artery.

In view of the small left pulmonary artery with severe cyanosis, decision was taken to do central shunt at present through midline sternotomy.

Anaesthetic considerations

The patient was kept in supine position and intubated with single lumen endotracheal tube, without bag and mask ventilation. Ventilator settings were kept with peak inspiratory pressure (PIP) of ≤ 25 cm H2O and a positive end-expiratory pressure (PEEP) of 2–5 cm H2O, and the rate was adjusted to achieve PaCO2 of 45 to 60 mmHg, to minimize the lung barotrauma.

The patient was taken for central shunt (aorta to main pulmonary artery) on cardiopulmonary bypass. A 4-mm polytetrafluoroethylene (PTFE) graft was placed and the patient was weaned off cardiopulmonary bypass uneventfully. Saturation of 85% was achieved. The patient was extubated on postoperative day one. Postoperative CT angiography showed a patent central shunt (Fig. 2). Due to presence of only single lung, the patient was kept on diuretics to prevent overflow of shunt leading to pulmonary congestion. The patient had an uneventful postoperative course and was discharged on postoperative day six.

Fig. 2.

CT angiography image of the patient showing the patent shunt between aorta and the main pulmonary artery with the liver in the right chest cavity. CT, computed tomography

Discussion

The reported birth prevalence of CDH ranges from 1.4 to 4.5/10,000 births [1]. CDH is mostly common on the left side and on the right side; it constitutes about 27% [4].

CDH in cases of CVM has been reported with birth prevalence of 9/1549 (5.8%) [1]. The combination of these two entities result from a major abnormality in development, which may be associated with lung hypoplasia and pulmonary vascular disease, leading to difficulty in managing these very sick children.

CVM, in patients with CDH, may range from atrial and ventricular septal defects, to single ventricular physiology. However, an increased frequency of conotruncal CVMs, in association with CDH, is not a consistent finding in the literature [1].

Although it is uncommon for diaphragmatic hernias to present late, Kitano et al. reported late presenting diaphragmatic hernias, with a mean age of 72 days. Out of 79 cases, 10 patients had congenital heart disease (CHD) and one of these 10 patients had TOF [4].

There is significant heterogeneity in managing these patients with a combination of CDH with CHD, besides high morbidity and mortality. There are no guidelines, and hence, management has to be individualized. In most of the developed countries, these conditions are picked during antenatal care, and hence, management becomes a little predictable. Even in those situations, patient may require preoperative ventilation, and sometimes, extracorporeal membrane oxygenation [5].

Management dilemma

These patients present a management dilemma, even if diagnosed during antenatal care, but more so when diagnosed late. They can be managed by three possible pathways:

1. Both CDH and CHD, TOF in the index case, treated during same sitting.

2. CDH is treated first, followed by treatment of CHD [6].

3. CHD treated first, followed by CDH.

Best scenario is when the diagnosis is made antenatally, baby is delivered under proper hospital care, and if stable enough, both conditions are treated in a single stage.

Second scenario is to treat diaphragmatic hernia first, when they present in neonatal period, and to treat cardiac condition later, once they are stabilized.

Third scenario is applicable when the patient presents with cardiac issues, such as severe cyanosis or cyanotic spells, or acute deterioration of stable cardiac symptoms, where cardiac cause should be treated first and once the child is stable, diaphragmatic hernia can be dealt with. However, management decisions of these conditions must go through a multidisciplinary approach and treatment individualized for getting optimum results.

This patient presented with severe cyanosis and failure to thrive of 2-month duration. Recent deterioration of symptoms was attributed to the underlying cardiac condition of TOF. Multidisciplinary team therefore decided to approach this patient in two stages, owing to late presentation, and to manage cardiac condition first and when stable, to correct the diaphragmatic hernia in second stage.

This patient was deemed extremely sick, with suboptimal anatomy for total correction of TOF, and was therefore managed with a shunt. She will now require diaphragmatic hernia repair, which itself is a major surgery, at a later date.

Funding

Nil

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Informed consent

Informed consent was taken from patient’s parents.

Human and animal rights

No experiment involving human or animals.