An infant with acute decompensated heart failure caused by afterload mismatch due to tumour-induced secondary hypertension: a case report

Abstract

Background

Hypertensive crisis is a relatively rare condition among infants and usually occurs secondary to an underlying disease. If not managed promptly, it is life-threatening and can lead to irreversible damage to vital organs. While secondary hypertension due to tumours has been reported previously, acute decompensated heart failure is rare, especially in the paediatric population.

Case summary

A 2-month-old female infant presented with poor feeding and poor body weight gain. She was extremely ill, and blood gas analysis showed prominent acidosis (pH 6.945). The patient was intubated and referred to our hospital for further care. Her arterial blood pressure (BP) was as high as 142/62 mmHg. Echocardiography showed decreased left ventricular function with an ejection fraction of 19.5% and a left ventricular end-diastolic diameter of 25.8 mm (Z score = 2.71). We promptly started treatment with antihypertensive drugs. She had no congenital heart disease or any lesions that may have caused an increased afterload. There was no palpable mass suggestive of the tumour; however, close examination with abdominal echo and subsequent contrast-enhanced computed tomography confirmed a left kidney mass. Blood tests suggested renin-dependent hypertension due to the tumour causing an excessive afterload. Laparoscopic left nephrectomy improved cardiac function improved as BP decreased.

Discussion

Blood pressure measurement is often omitted in daily practice when examining infants because of difficulty in measurement. However, BP may be the only detectable sign in patients with secondary hypertension before decompensated heart failure, and BP should also be measured in infants.

Introduction

Delayed diagnosis of life-threatening diseases remains a significant clinical challenge because of difficulties in performing accurate medical examinations in infants. Blood pressure (BP) measurement is often omitted when examining infants in the daily practice because it is challenging to measure BP in this population, and BP fluctuates considerably due to reasons such as crying, body movements, and feeding.¹

Although secondary hypertension due to tumours has been reported, cases of acute decompensated heart failure are rare, especially among infants.

Timeline

Case presentation

A female infant was born to a healthy mother at 37-week and 6-day gestation. The pregnancy was unremarkable. Her birth weight was 2835 g. There was no other significant medical history, and the family history was also unremarkable. At the 1-month check-up, her weight gain was +28 g/day, which was slightly poor. There were a little developmental concerns, and the 2-month check-up was scheduled.

At the 2-month check-up, the parents reported poor feeding, and her weight gain was +10 g/day. Therefore, she was referred to local secondary care. The patient appeared extremely ill. Oxygen saturation was 20–30% even after supplying 10 L of oxygen via an oxygen mask, and venous blood gas analysis showed prominent acidosis (pH, 6.945; pCO₂, 42.4 mmHg; HCO₃, 15.5 mmol/L; BE, −17.8 mmol/L; lactate level, 14.3 mmol/L). The patient was intubated and transferred to our hospital for further care.

At the time of admission to the intensive care unit, her vital signs were as follows: heart rate, 235 b.p.m. (normal: 123–164 b.p.m.)²; arterial oxygen saturation, 90%; and BP, 142/62 mmHg (the 95th percentile value for systolic BP: 106 mmHg; the 50th percentile value for systolic BP: 91 mmHg).³ This BP was well above the 95th percentile value in 2-month infants. The patient presented with peripheral coldness, generalised pallor, and reticulitis.

She had developed circulatory failure, caused by afterload mismatch due to secondary hypertension. The reduced cardiac pump function had resulted in systemic and myocardial tissue circulatory failure and hypoxia, leading to cardiogenic shock. She was started on inotropic support with several antihypertensive medications: furosemide, phentolamine, and enalapril.

A cardiovascular examination revealed gallop rhythm and diastolic murmur in the aortic area. Chest auscultation revealed bilateral rales as previously described. The patient had no palpable mass suggestive of a tumour on physical examination.

Blood tests showed elevated levels of brain natriuretic peptide (BNP) (8003 pg/mL), cortisol (160 µg/dL, normal: 3–23 µg/dL), plasma renin activity (110 ng/mL/h, normal: 0.2–2.7 ng/mL/h), and aldosterone (1340 ng/mL, normal: 2–13 ng/dL). The creatine phosphokinase level was not elevated. Electrocardiography showed left ventricular hypertrophy (Figure 1). There were the high R wave in V1, the deep S wave in V6, and the high R wave and negative T wave in V6. Echocardiography showed a diffuse hypokinetic left ventricle with an ejection fraction (EF) of 19.5% and a left ventricular end-diastolic diameter (LVDd) of 25.8 mm (Z score = 2.71) (Figure 2).⁴ The right ventricular myocardial performance index (RV Tei index) was 0.47 (the normal value: 0.24 ± 0.04).⁵ Because of pulmonary hypertension due to significant left ventricular dysfunction, she had haemoptysis at the arrival. Her right heart function was also affected. Chest radiography revealed pulmonary congestion with a cardiothoracic ratio of 54.1% (Figure 3).

Despite the significantly poor cardiac function on admission, her BP was elevated, and decompensated heart failure due to secondary hypertension was suspected. Close examination with abdominal echo and subsequent abdominal contrast-enhanced computed tomography revealed a weakly enhanced abdominal mass, later identified as a left renal tumour (Figure 4). We concluded that the infant had secondary hypertension due to a renal tumour causing afterload mismatch, which led to acute decompensated heart failure and cardiogenic shock.

Ten days after the infant’s admission, a laparoscopic left nephrectomy was performed. Histopathological examination revealed a diagnosis of mixed-type congenital mesoblastic nephroma (Figure 5), and chemotherapy was administered in addition to surgical resection. Cardiac contractility, left ventricular enlargement, and hypertension gradually improved as the BP decreased within several weeks. The intravenous antihypertensive medications were terminated 25 days after admission, and she was switched to oral angiotensin-converting enzyme inhibitor and diuretics only. At the time of discharge from the hospital, 101 days after admission, improvements in BP (92/45 mmHg), left ventricular EF (LVEF) (77.4%), LVDd [19.9 mm (Z score = 1.14)],⁴ plasma renin activity (3.1 ng/mL), and aldosterone (24.6 ng/dL) were noted. Six months after discharge from the hospital, the patient was able to cease oral medications. After discharge from the hospital, she was followed up with echocardiography and electrocardiography once every 3 months in the outpatient clinic. We were been able to confirm that the cardiac function was good.

Discussion

Among infants, feeding difficulties, unexplained tachypnoea, apnoea, lethargy, irritability, or seizures may constitute symptoms of unsuspected hypertension.⁶ There have been several reports on resting BP standards among infants. Goble et al. reported that the 95th percentile values were levels above which infants might be considered hypertensive if these levels were sustained. Systolic BP increases sharply between birth and 2 months of age. However, there is no significant difference between the systolic BP measured at 2 months and 1 year. The 95th percentile value for systolic BP in infants aged between 2 months and 1 year was 113 mmHg.³ However, difficulty in maintaining infants at rest and measuring their BP during outpatient visits is not uncommon. Blood pressure can vary based on the level of activity of the infant, from sleeping to a wakeful state or crying, feeding, or even being held head-up. The reliability of repeated BP measurements decreases among infants also when they are in a non-calm state.⁶

During infancy, acute systemic hypertensive episodes are most likely to be unrecognised and may remain underdiagnosed. Hypertension in neonates is rare, with its incidence ranging from 0.2% to 3.0%.⁷ Additionally, in selected groups of hypertensive children who have undergone angiography, renal artery stenosis has been found in 4–20% of children, and caution should be exercised when hypertension is present.⁸

In addition, the rapid progression of organ damage associated with hypertension is called a hypertensive crisis, affecting 1–2% of hypertensive patients. Most patients with the hypertensive crisis are often reported to exhibit non-specific symptoms, such as headache without neurological deficit, dizziness, vomiting, and palpitation. In contrast, heart-related symptoms are less common.⁹ Very little is known about the incidence of acute hypertensive crisis among infants.¹⁰

While the causes of paediatric heart failure are mostly congenital heart disease,¹¹ secondary hypertension due to tumours could lead rapidly to decompensated heart failure with excessive afterload mismatch, as in this case. Infants, especially those under 2 years of age, in response to pressure overload, were more likely to present with congestive heart failure with reduced contractility and cardiac enlargement.¹² In addition, the left ventricle in infants cannot tolerate high afterload because cardiac shortening is depressed more than in older children.¹³ In this case, she also shows compensatory left ventricular hypertrophy, but rather marked left ventricular enlargement.

Blood pressure measurements are an important diagnostic tool in paediatric practice for the early detection of certain diseases, as well as for the management of patients with alterations in BP.¹ Particularly, infants are incapable of expressing their symptoms clearly. In addition, hypertension is often diagnosed in the context of heart failure because of the lack of clinical symptoms and non-specific manifestations.⁶ Decreased feeding and poor liveliness may be signs that may indicate the severity of a condition in the infants. In this case, as BP may be the only sign that can be detected before decompensated heart failure, BP measurement should be performed for infants with weight gain concerns.

Conclusion

We conclude this case report and discussion with a few key learning points. In cases where the tumour size is small, secondary hypertension due to the tumour may not be clinically noticeable until the patient enters vital shock. It is essential to check for vital signs, including BP, for infants with weight gain concerns.

Lead author biography

Shuhei Yoshida graduated from the Kyoto Prefectural University of Medicine in 2018. After completing his residency, he is currently training as a general paediatrician at Kurashiki Central Hospital. He has a particular interest in paediatric intensive care.

Supplementary material

Supplementary material is available at European Heart Journal – Case Reports.

Acknowledgements

We would like to thank Editage (www.editage.com) for English language editing.

Slide sets: A fully edited slide set detailing this case and suitable for local presentation is available online as Supplementary data.

Consent: The authors confirm that written consent for submission and publication of this case report including the images and associated text have been obtained from the patient in line with COPE guidance.

Funding: None declared.

Data availability

No new data were generated in support of the article.

References

Author notes