Confirmatory, intraoperative, transesophageal echocardiography in an infant with congenital coronary artery anomalies: A case report

Abstract

Anomalous left coronary artery from pulmonary artery (ALCAPA) is a rare congenital cardiac defect mostly presenting in early infancy. Various imaging modalities are used to make the diagnosis. Circumstances during these investigations should be considered and intraoperative assessment should be interpreted taking preoperative results into account. We are reporting a case of a patient diagnosed preoperatively as an ALCAPA. During intraoperative transoesophageal echocardiography and surgical inspection, the diagnosis was changed to normal left coronary artery with an ostium from the aortic left coronary cusp, with a coronary arteriovenous fistula between the left main stem coronary artery and pulmonary artery. An 8-month-old female presented to pediatric cardiology with symptoms of heart failure and failure to thrive. She was born premature (gestational age 35 weeks) via normal vaginal delivery with a birth weight of 2.2 kg and no neonatal complications or admissions. From the patient's clinical presentation, special investigations were performed, including a chest X-ray (CXR), electrocardiogram (ECG), preoperative transthoracic echocardiography (TTE), cardiac catheterisation, and coronary angiogram. The initial preoperative TTE revealed a dilated left atrium (LA), massively dilated and hypocontractile left ventricle (LV) with moderate mitral incompetence and mild tricuspid incompetence. The ejection fraction (EF) was measured to be 25%. The CXR and ECG were also typical of ALCAPA. She was diagnosed with ALCAPA and presented for surgery. Surgery involves reimplantation of the left coronary artery (LCA) from its abnormal origin.1 On the day of surgery, the patient weighed 6.8 kg. We offered the patient an intravenous induction with fentanyl 15 μg, etomidate 1.5 mg, and rocuronium 5 mg. The anesthesia was maintained with sevoflurane and oxygen at an end-tidal percentage (Et%) of 1.7% and fraction of inspired oxygen (FiO2) of 60%. The course of the induction and maintenance of anesthesia were uneventful. On perioperative transoesophageal echocardiography (TOE), it was confirmed that the LV was severely dilated and hypocontractile with moderate mitral incompetence. It was also noticed that there was a left coronary artery (LCA) originating from the left coronary cusp (LCC) with another communication and Doppler flow from the LCA/LCC to the pulmonary artery (PA) (Figure 1). After consideration of all the preoperative investigations and intraoperative TOE results, it was decided not to proceed with the planned procedure for the diagnosis of ALCAPA. The cardiothoracic surgeons could visualize the fistula between the LCA and PA and ligated the fistula with no hemodynamic sequelae. The patient was hemodynamically stable, extubated in theater at the end of the surgery and transferred to the cardiothoracic intensive care unit with an appropriate postoperative analgesia plan. On follow-up, the patient's cardiac function improved gradually. One week postoperatively, the EF improved from 16% to 32%. Coronary artery anomalies occur in 1% of the population.2 These anomalies can be categorized into congenital and acquired anomalies and may present with signs and symptoms of myocardial ischaemia, infarction, and heart failure requiring surgical intervention, or may be completely asymptomatic, not requiring any intervention.2 Of the many congenital coronary anomalies, anomalous left coronary artery from pulmonary artery (ALCAPA), although still rare at an incidence of one in 300 000 live births, is the most common cause of myocardial ischaemia in childhood.2 ALCAPA has a mortality rate of up to 90% if not treated, while the combined postoperative mortality rate of all surgical techniques ranges between zero and 23%.1, 2 Other congenital coronary anomalies include (i) coronary artery fistula; (ii) a lack of origin or ostial atresia; (iii) an abnormal origin such as ALCAPA; and (iv) an anomalous course.2 Congenital coronary anomalies could have similar clinical features.2 In the case we reported here, the diagnosis of ALCAPA was made based on clinical signs and symptoms and special investigation results. On perioperative TOE, it was found to be a different kind of congenital coronary anomaly. The TOE diagnosis was suggestive of another pathology, which was a coronary arteriovenous fistula (CAVF) between the mainstem LCA and PA. The team involved suspected a coronary steal phenomenon as the reason for the patient presenting with myocardial ischaemia and heart failure, mimicking ALCAPA signs and symptoms. Coronary arteriovenous fistula (CAVF) is present in 1%–2% of the population.1 It is an anomalous connection between a coronary artery and a major vessel or cardiac chamber and usually arises from the right coronary artery (RCA) but could also arise from the LCA and left anterior descending artery (LAD), with termination sites usually in the PA, right ventricle (RV), or right atrium (RA). CAVF is difficult to detect2-4 and appears to represent a persistence of embryonic intratrabecular spaces and sinusoids.2, 3 They are usually asymptomatic, but could present with signs and symptoms of myocardial ischaemia and heart failure.2-4 Although coronary angiography is viewed as the gold standard to diagnose CAVF, intraoperative TOE can be used in conjunction with preoperative investigations to complement each other in confirming a diagnosis.3-5 However, TOE does have limitations. Although having a much better acoustic window in children than adults, it may not detect flow in the distal site of a CAVF.4 In this case, the TOE findings assisted to prevent the patient from having surgery with a high mortality rate. Identifying the CAVF and excluding the diagnosis of ALCAPA preoperatively might have led to a more favorable outcome for this patient. Intraoperative echocardiography is very valuable in confirming a diagnosis and determining the severity of disease. TOE is also useful in monitoring changes and success of surgical interventions for complex congenital cardiac anomalies. Communication between the team members managing the patient is of utmost importance, discussing every aspect of the case, including all investigation results, the procedure planned, and any changes noted perioperatively. Team communication will lead to improved patient management and outcomes. Daleen Struwig, medical writer/editor, Faculty of Health Sciences, University of the Free State, for technical and editorial preparation of the article. The authors have no conflict of interest to declare. Approval to publish this care report was obtained from the Health Sciences Research Ethics Committee (HSREC) of the University of the Free State in Bloemfontein, South Africa (ethics reference number UFS-HSD2024/0028/2603). The patient's mother (single parent) signed consent for the case report to be published. Data sharing is not applicable to this article as no new data were generated or analyzed.