Sudden cardiac death due to angiofibroma: a case report

¹Department of Obstetrics and Gynecology, School of Medicine, University of Nairobi, Nairobi, Kenya, ²Department of Obstetrics and Gynecology, Machakos Level 5 Hospital, Machakos, Kenya, ³Department of Human Pathology, Anatomic Pathology Unit, School of Medicine, University of Nairobi, Nairobi, Kenya, ⁴Department of Pediatrics and Child Health, School of Medicine, University of Nairobi, Nairobi, Kenya

^&Corresponding author
Duncan Mwangangi Matheka, Department of Obstetrics and Gynecology, School of Medicine, University of Nairobi, Nairobi, Kenya

Introduction    

Pediatric neoplasms are rare causes of morbidity and mortality. While malignant pediatric neoplasms such as Wilm's tumor are well known, there is need for awareness concerning the burden of disease due to benign neoplasms. These neoplasms have major clinical consequences requiring multidisciplinary surgical intervention, without which many of them are fatal. Benign pediatric neoplasms involving critical organs such as the heart are associated with high mortality rates. Angiofibromas are benign but locally aggressive vascular tumors that occur in the nasopharynx, neck and face. These are rare soft tissues hamartomas which contain mainly blood vessels and fibrous tissues, and are often found in association with Tuberous Sclerosis (TS) [1]. Angiofibromas located in sites other than head and neck regions are rare. We report a massive interventricular tumor in a 5-month-old who died suddenly, and an autopsy diagnosis of cardiac angiofibroma was made. Cardiac angiofibromas are rare and unique occurrences, whose reports should be published when available to inform medical practitioners.

Patient and observation     

Patient information: JT, a male infant who died at the age of 5 months and was the second born child in his family. His parents were not related and the older female sibling is alive and well, and there was no known family history of cardiac disease or any other known genetic or chronic condition. Three antenatal obstetric scans were all normal and did not detect any morphological abnormality. Delivery was through elective repeat caesarian section at 39 weeks of gestation due to a previous caesarian delivery for the older sibling. His birth weight was 3300 grams, had Apgar score of 10 in 5 minutes, had normal head circumference and no congenital anomalies reported at birth. He received appropriate childhood vaccines and his growth and developmental milestones were normal.

Clinical findings: feeding was normal, but he had a persisting cough, wheezing and dyspnea at three months of age. Occasional sweating was reported even at rest.

Timeline of current episode: when he was three months old, he had persisting cough for a week, with associated occasional wheezing and dyspnea. He had normal SPO2 levels, and was diagnosed with bronchiolitis - following which he was admitted and nebulized severally. He was also put on nasal drops and nasal sprays, antihistamines, antibiotics, salbutamol and protein pump inhibitors. Symptoms resolved temporarily following the symptomatic management above.

Diagnostic assessment: full hemogram, C-reactive protein, procalcitonin and other blood investigations were non-remarkable. A chest X-ray revealed a mild cardiomegaly. Serial echocardiograms showed a well-circumscribed, homogenous, highly vascularized mass filling the left ventricle (Figure 1). Other cardiac sites were normal.

Diagnosis: the results were consistent with cardiac disease, possibly congenital.

Therapeutic interventions: partial surgical excision was planned, but not done due to financial constraints.

Follow-up and outcome of interventions: the patient died suddenly after an abrupt loud unusual scream. He was rushed to the nearby hospital where he was pronounced dead on arrival. On autopsy, the main findings at external examination were a well-developed and well-nourished child. Major findings were in the respiratory and cardiovascular systems. There was a large cardiac tumor involving 80% of the heart mass, located in the interventricular and interatrial septum. This extended into the left ventricular wall (Figure 2). The tumor consisted of blood vessels and fibrous connective tissue with sparsely distributed cardiac myocytes, suggesting a birth defect characterized by disorganized cells into the organ (Figure 3). The heart was enlarged due to the large benign neoplasm within the septum and this compressed all chambers into small slit-like spaces. Both lungs were heavy, soft and with frothy fluid within the airways. On histological examination, the lungs showed diffuse pulmonary edema with marked vascular congestion, while the cardiac neoplasm was an angiofibroma (Figure 4). The sections of the brain showed cerebral edema. The neurons and glia were of normal morphology. All other tissues, systems and organs showed normal morphology.

Informed consent: informed consent was obtained from the patient's parents.

Discussion     

Large cardiac tumors are sometimes seen in infants and can be a cause of sudden cardiac death as reported in the current case [1]. Although the majority are benign and non-invasive, they may have significant hemodynamic consequences depending on their size and location. The most common type of tumors reported in children and adolescents are rhabdomyomas, which are associated with TS complex in 50% of the cases [1]. Other benign tumors are fibromas, myxomas and teratomas [2]. On the other hand, sarcoma is the largest group of primary cardiac malignant neoplasms [3].

For angiofibromas, the usual location is mainly the nasopharynx, head and neck region where it presents with nasal obstruction and nose bleeding. It is most common in adolescent males and thus also referred to as juvenile nasopharyngeal angiofibroma [4]. Histologically, these tumors are well-circumscribed but not encapsulated and are composed of collagenized fibrous stroma with vessels ranging from small slit-like spaces to dilated lumens. No significant cytologic atypia is observed, but multinucleated stromal cells are sometimes seen [5]. The vascular nature is highlighted by angiograms that show a rich blood supply. Angiofibroma is rare to present as cardiac tumor [6].

The clinical features described in the current case show a large cardiac angiofibroma involving the septum and the left ventricular wall. It was associated with pulmonary edema and vascular congestion. The clinical presentation of a patient with a cardiac tumor is determined more by the tumor's location than by its histologic type, varying widely from asymptomatic presentations to life-threatening cardiac events possibly due to sudden or critical inflow or outflow obstruction at the lumen, valve or outflow tract therefore causing significant hemodynamic consequences that could explain the sudden cardiac death witnessed in our patient. Moreover, based on the tumor's size and position, it may induce arrhythmias and interfere with ventricular compliance [7].

Following the rapid growth of tumor mass in small-sized cavities, Congestive Heart Failure (CHF) can be evident and surgical treatment may be lifesaving. Cardiac tumors often present with CHF manifested by fatigue, edema, jugular venous distention, ascites, shortness of breath, syncope and night sweats. Pericardial effusions, venacaval syndrome, pulmonary embolism and restrictive cardiomyopathy may be some of the complications. Because tumors may embolize, they can also lead to seizures, transient ischemic attacks and cerebrovascular and peripheral-vascular accidents [8]. Echocardiogram is an excellent tool to diagnose the tumor. However, precise information on the tumor histotype is not attainable by echocardiography [9]. A correct therapeutic plan requires an accurate histopathologic diagnosis of the resected mass to rule out the rare case of a malignancy. Computerized Tomography (CT) scan, Magnetic Resonance Imaging (MRI) and Electrocardiography (ECG) are also useful in making the diagnosis.

In the current case, we lost the child as surgical intervention was being planned. With the huge extension of the cardiac tumor, involving the interventricular and interatrial septum, it was only amenable to partial surgical resection as had been discussed and planned. The radical solution of cardiac transplantation was out of reach, due to the local situation and the age of the patient. Generally, the mode of management of these tumors varies and cannot be easily simplified because the kind of tumor (whether benign or malignant, or infiltrative or localized) dictates therapy. Location and extent of the tumor, as well as symptoms, are clinical variables that direct treatment. Watchful observation is sufficient when the mass is small and does not interfere with vascular hemodynamics. However, when the tumor is causing hemodynamic problems by either obstructing the outflow tract, valve or causing rhythm abnormalities, aggressive management by surgical intervention should be done [8]. In occasional cases, implantation of a pacemaker may be needed if atrioventricular block occurs.

Conclusion     

Cardiac angiofibromas are rare and unique pediatric neoplasms and as seen in this report, invariably fatal. There are no series describing the definitive management of these rare cardiac tumors. More insights into their pathogenesis, prevention and treatment are required. There is no definite genetic basis for cardiac angiofibromas and consequently, no notable inheritance patterns. Cardiac centers in low- and middle-income countries should be better resourced to manage unique cases like for the current infant.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Patient management: Christine Yuko Jowi and Edwin Walong. Manuscript drafting: Duncan Mwangangi Matheka. Manuscript revision: Duncan Mwangangi Matheka, Edwin Walong, Christine Yuko Jowi. All authors approved the final version of the manuscript.

Figures     

Figure 1: echocardiograph of the cardiac mass

Figure 2: gross appearance of the interventricular cardiac mass after autopsy

Figure 3: photomicrograph of the cardiac mass on histology at high power

Figure 4: photomicrograph of the cardiac mass on histology at low power

References