A 3rd ventricular colloid cyst causing acute hydrocephalus with stunned myocardium: A case report

Background: Third ventricular colloid cysts are benign but may cause acute hydrocephalus, raised intracranial pressure, decreased consciousness level, and sudden death. These ventricular colloid cysts associated with stunned myocardium are rarely reported in the literature. This study reported a case of a third ventricular colloid cyst presented as acute hydrocephalus complicated with severe neurogenic pulmonary edema, stunned myocardium, and heart failure, which survived at the end. Case presentation: A 29-year-old woman presented to the emergency department with one day history of headache, vomiting, and altered consciousness level. Early brain imaging showed a cyst in the third ventricle. The patient rapidly deteriorated neurologically and developed severe pulmonary edema and heart failure requiring immediate external ventricular drain and heart failure management. Once stabilized, she underwent endoscopic excision of the ventricular cyst. Histopathology confirmed the diagnosis of colloidal cyst. She survived all these acute life-threatening events, improved, and stabilized, and was discharged home. She was followed up in outpatient clinics after 6 months of discharge with no symptoms or neurological deficit. Conclusion: A third ventricular colloid cyst can cause acute hydrocephalus leading to stunned myocardium requiring immediate surgical intervention, advanced hemodynamic monitoring, and acute heart failure management.


INTRODUCTION
The third ventricular colloid cyst is a rare congenital lesion of endodermal origin. It is one of the causes of headache and sudden death 1 and is more common in individuals in the third to fifth decades of life but can occur in children and young adults as well. 2 Radiological imaging such as brain magnetic resonance imaging (MRI) and computed tomography (CT) scans are essential to diagnose these ventricular cysts. The classical location of these cysts makes it essential to recognize, diagnose, and properly manage it early on to avoid potentially life-threatening complications. These third ventricular cysts causing acute obstruction to cerebrospinal fluid (CSF) flow can lead to hydrocephalus, brainstem herniation, and brain death. Several case reports of third ventricular colloid cysts have been reported in the literature presenting with hydrocephalus only without cardiac involvement. However, a third ventricular colloid cyst, which causes stunned myocardium, neurogenic pulmonary edema, and heart failure, is reported only in six cases in the literature. 3 -7 Five of which had sudden cardiac arrest and died and were diagnosed as colloidal cysts on autopsy. This study presented a young woman with colloid cyst of the third ventricle who developed acute hydrocephalus, severe neurogenic pulmonary edema, and heart failure with a better outcome.

CASE
A 29-year-old woman, previously healthy, presented to the accident and emergency department with complaints of fronto-occipital headache and decreased consciousness level for the last 24 hours. The symptoms suddenly started and included photophobia, neck pain, and nonprojectile vomiting (four times). She had urine incontinence and drowsiness. No further symptoms or signs were present on admission. Her vital signs were stable, and she was afebrile. Her Glasgow coma score (GCS) was 12/15 (E3 M5 V4), and pupils were 3 mm bilaterally and reactive to light. Her laboratory values showed leukocytosis (white blood cell: 22.5 £ 10 3 /mL, neutrophils 42%, hemoglobin 13.3 gm/dL, platelet 318 £ 10 3 /mL), high lactate 4.8 mmol/L, and normal glucose, electrolytes, and liver and kidney function tests. A CT head scan showed isodense rounded lesion seen at the level of the foramen of Monro measuring 13 £ 15 mm, which was likely a cyst with secondary significant dilatation of the lateral ventricles with brain edema.
Few hours later, the patient became unresponsive with drop of GCS to 3/15, tachycardic (heart rate 160 beat/min), and hypertensive (blood pressure 150/110 mm Hg). Pupils were unequal in size; right 8 mm nonreactive and left 6 mm reactive to light. The patient was immediately intubated and escorted to the operating room (OR) for emergency external ventricular drain (EVD) insertion. Upon connecting her to the anesthesia ventilator in the OR, she had pink frothy secretions from the endotracheal tube, high peak airway pressures of 40 cm H2O, and oxygen saturation (SO2) 92%, and she needed fraction of inspired oxygen (FiO2) of 100%. The clinical diagnosis of pulmonary edema was made, and she was given furosemide and morphine and was escorted to the surgical intensive care unit where she was sedated with remifentanil and dexmedetomidine infusions. Her pupils were 2 mm bilaterally equal and reactive to light after the EVD insertion. Noradrenaline infusion was required to maintain adequate hemodynamics. Her chest had bilateral crepitations, and chest X-ray showed bilateral infiltrates ( Figure 1). Her arterial blood gas showed metabolic acidosis (pH 7.26, PCO2 43 mm Hg, PO2 74 mm Hg, lactate 2.5 mmol/L, SO2 94%, BE: 27 mmol/L, HCO3 18 mmol/L, and PO2/ Fio2 148 mm Hg). Cardiac biomarkers were elevated (pro B-type natriuretic peptide 3825 pg/mL and highly sensitive troponin T: first set 1917, second set 1085, and third set 756 ng/L). Electrocardiogram (ECG) showed T-wave inversion in leads I, aVL, V2, and V3 ( Figure 2). A right femoral arterial pulse-induced continuous cardiac output (PiCCO w ) catheter was inserted for

DISCUSSION
The ventricular colloid cysts are benign cysts filled with mucin and covered by epithelial cells. They usually arise from the roof of the third ventricle immediately posterior to the foramen of Monro. 8 Depending on their site, size, and CSF obstruction degree, they can cause various neurological symptoms, ranging from headache to sudden death due to brainstem herniation. 1 Several case reports of colloid cyst presenting with headache, hydrocephalus, or increased ICP but without cardiac involvement have been reported. However, only six cases of a third ventricular colloid cyst associated with neurogenic pulmonary edema and cardiac complications were reported in five articles and found in the literature. 3 -7 Table 2 summarizes these cases with their outcomes. Only one of them survived and had a resection of the cyst surgically with only mild memory disturbance on follow-up. This case was a young female presented with a third ventricular colloid cyst causing acute hydrocephalus leading to severe pulmonary edema, stunned myocardium, and heart failure. The survival of this case was attributed to early detection and proper intracranial pressure (ICP) management with early bilateral EVD insertion and heart failure control with inotropic support and vasopressors guided by invasive cardiac output monitoring and PiCCO line measurements. The patient survived and underwent complete endoscopic resection of the colloid cyst and discharged home. Previously reported colloid cyst cases and sudden cardiac death diagnosed on autopsy mentioned the histopathological appearance of coagulative myocytolysis and contraction band necrosis (CBN) of myocardial specimens. 3 CBN is observed as a histological hallmark of an adrenergic overstimulation. Neurogenic myocardial stunning due to hyperacute sympathetic overstimulation may represent the cardiac events that occur because of increased ICP 9 . As the hypothalamic cardiovascular regulatory centers are located close to the walls of the third ventricle, these structures can be compressed by the growing cyst and can explain the reflex cardiac events associated with it. The resultant neurological crisis that occurs because of hypothalamus compression and high ICP stimulates the vasomotor centers, which leads to massive autonomic sympathetic discharge, pulmonary edema, and stunned myocardium. The increased catecholamine levels can lead to an increase in the left atrial pressure and systemic hypertension, which negatively affects left ventricular performance. Sympathetic discharge can also cause pulmonary venoconstriction, increase vascular permeability, and develop pulmonary edema. 10 This patient was followed up in outpatient clinics for 6 months. She had no symptoms and no neurological deficit. Follow-up head MRI showed complete removal of the cyst, and follow-up ECHO was within normal limits. The limitation of this study is that this neurogenic pulmonary edema and stunned myocardium were presented in a single case. A case series is required for better data and conclusion.

CONCLUSION
The proximity of the third ventricular colloid cyst to the hypothalamus and vasomotor centers of the brainstem can cause sympathetic overstimulation and lead to life-threatening pulmonary edema, stunned myocardium, and heart failure, which requires immediately relieving raised ICP, advanced hemodynamic monitoring, taking anti-pulmonary edema measures, and continuing heart failure management, which can lead to survival.

CONSENT
Written informed consent was obtained from the patient for publication of this case report and any relevant investigations and imaging studies.

ETHICS APPROVAL
We obtained permission from the Medical Research Center (Project Ref. No: MRC-04-18-224) of Hamad Medical Corporation for the publication of this case report on the condition of no patient identifiable data (including patient name and photograph).