INTRODUCTION
Cardiovascular complications of raised intracranial pressure (ICP) are common in adults but have rarely been reported in children. These include bradycardia, hypertension, and rarely ventricular arrhythmias [1]. Common morphological changes on the electrocardiogram (ECG) include ST-segment changes, flat or inverted T waves, prominent U waves, and prolongation of QTc [2]. Autonomic factors are frequently associated with arrhythmogenesis [3]. Autonomic imbalances, including increased vagal tone and hypersympathicotonia, can trigger arrhythmias [3]. The trigeminocardiac reflex and central autonomic network disturbances during elevated ICP have been proposed as the mechanisms underlying cardiac dysrhythmias [1,4].
The most frequent arrhythmias that occur after brain injury are premature ventricular complexes, sinus arrhythmias, and atrial fibrillation. Other arrhythmias, including atrial flutter, supraventricular tachycardia (SVT), ventricular tachycardia (VT), torsades de pointes, ventricular fibrillation, and asystole, have been documented [2]. Although several adult studies have described neurogenic arrhythmias, pediatric reports have been limited to isolated cases. Our study adds to this gap by describing five children with raised ICP who developed malignant arrhythmias, highlighting the neurocardiac link and the need for timely recognition in pediatric neurocritical care.
CASE REPORTS
Case 1
An 8-year-old male presented with a 5-day history of headache and vomiting, altered consciousness, and two generalized tonic-clonic seizures. Neuroimaging revealed a 10-mm cerebellar tonsillar herniation with fourth ventricular compression, suggestive of an Arnold–Chiari malformation. Transcranial Doppler (TCD) showed an elevated pulsatility index (1.35), and bilateral optic nerve sheath diameters (ONSDs) were increased (right, 5.5 mm; left, 5.7 mm). Invasive ICP monitoring revealed an opening pressure of 79 mm Hg. Despite tier 2 management strategies including hyperosmolar therapy and sedation, ICP remained refractory. The patient developed autonomic instability, premature ventricular contractions (PVCs), and sustained monomorphic VT. The arrhythmias were successfully controlled with intravenous amiodarone. His serum electrolyte levels were normal and echocardiography did not reveal any structural causes. Phenobarbitone coma was initiated with EEG-confirmed burst suppression, but ICP remained unrelieved. Neurosurgical decompression was considered but was deferred because of hemodynamic instability. Follow-up TCD revealed absent diastolic flow, and the patient progressed to brain death within 24 hours.
Case 2
A 9-year-old previously healthy boy presented with a 1 day of fever and refractory status epilepticus, accompanied by decerebrate posturing. He presented clinical signs of raised ICP with bilateral enlargement of the ONSD enlargement (right, 6 mm; left, 5.8 mm). Anti-ICP measures, including hyperosmolar therapy and controlled hyperventilation, were initiated. During the preparation for invasive ICP monitoring, the child developed SVT, which resolved with intravenous adenosine. Correctable causes, such as dyselectrolytemia and high-dose vasoactives, were ruled out. Echocardiography was not performed during the episode. Post-stabilization ICP monitoring revealed an opening pressure of 62 mm Hg. One hour later, the patient developed pulseless VT requiring cardiopulmonary resuscitation and defibrillation. A return of spontaneous circulation was achieved. The patient subsequently developed monomorphic VT with pulse and was successfully treated with intravenous amiodarone and lignocaine. The serum electrolyte and calcium levels were normal. Echocardiography revealed a structurally normal cardiac anatomy with a mildly reduced ejection fraction (45%) considered secondary to post–cardiac arrest myocardial dysfunction. Phenobarbitone coma was initiated for the refractory ICP. Extensive infectious and autoimmune workups yielded negative results. A diagnosis of suspected febrile infection-related epilepsy syndrome was made, and intravenous methylprednisolone was administered for 3 days. The ICP and cardiac rhythm gradually stabilized. Antiarrhythmics were weaned off, and the child was extubated on day 7 of hospitalization. The child recovered with intact neurological function and was discharged without any residual deficits. He was able to interact with parents, perform independent activities, but had difficulty with speech and concentration.
Case 3
A 7-year-old boy presented with 4 days of fever, altered sensorium (Glasgow Coma Scale, E1V1M2), and refractory status epilepticus. He was administered a midazolam infusion and tier 1 anti-ICP measures. Persistent low sensorium post-seizure control prompted continuous EEG monitoring, which ruled out nonconvulsive status epilepticus. The bilateral ONSDs were elevated, prompting invasive ICP monitoring, which revealed an opening pressure of 32 mm Hg with stimulus-induced spikes of up to 45 mm Hg. Despite tier 2 interventions, the child developed worsening ICP (peak, 66 mm Hg) and autonomic instability on day 3, followed by VT without hemodynamic collapse. VT was terminated by the intravenous administration of amiodarone. Correctable causes, such as hypoxia, dyselectrolytemia, hypothermia, and acidosis, were ruled out. Extensive workup for infectious and autoimmune encephalitis yielded negative results. A clinical diagnosis of seronegative autoimmune encephalitis was made, and intravenous immunoglobulin and corticosteroids were initiated. ICP and clinical status gradually improved over 72 hours. The child was extubated on day 9 and was discharged on day 15 with full neurological recovery and age-appropriate activities.
Case 4
A 7-month-old infant presented with a 1-week history of fever and altered sensory function for 3 days. magnetic resonance imaging (MRI) imaging performed at a referral center confirmed a fungal brain abscess in the left frontotemporal lobe. On admission, the infant had an elevated ONSD, and cranial ultrasound showed loss of gray-white matter differentiation. TCD revealed elevated pulsatility and resistance indices. Due to the open anterior fontanelle, invasive ICP monitoring was not performed. The child was mechanically ventilated, and medical measures were initiated to control the elevated ICP. On day 3 after admission, the infant developed monomorphic VT without hemodynamic compromise, which resolved spontaneously with continued anti-ICP therapy. Those with reversible causes were excluded. Craniotomy with abscess excision and external ventricular drain insertion was performed on day 6. After a prolonged ICU stay, the child was discharged after 5 months of hospitalization. The child lost most milestones and required assistance in all activities.
Case 5
An 11-year-old previously healthy girl developed headaches and irritability following viral prodrome. Within 48 hours, the patient became unresponsive. Brain MRI revealed symmetrical thalamic involvement suggestive of acute necrotizing encephalopathy. Laboratory evaluation revealed coagulopathy, hyponatremia, transaminitis, and shock. After correction of the coagulopathy, invasive ICP monitoring was initiated, revealing an opening pressure of 80 mm Hg with peaks of up to 130 mm Hg. Despite tier 2 measures for ICP control, including phenobarbitone coma, the ICP remained elevated. She also developed neurogenic shock, for which fluid resuscitation was performed, and vasopressors were initiated. Decompression craniectomy was considered, but could not be performed because of hemodynamic instability. She developed autonomic instability, along with QTc prolongation and ST–T wave changes on ECG. On the second day, she had another peak ICP rise of 110 mm Hg, during which she developed an episode of SVT that was unresponsive to adenosine and required synchronized cardioversion. Serum electrolyte levels and echocardiographic findings remained normal. Although she was receiving high doses of adrenaline and noradrenaline, the temporal rise in ICP preceding SVT suggested that the arrhythmia was likely related to increased ICP. Ultimately, the patient succumbed to refractory intracranial hypertension with progression to multiorgan failure on the third day of admission.
DISCUSSION
This case series highlights a rare but potentially life-threatening complication, malignant arrhythmia, defined as rapid VT lasting more than 30 seconds, causing hemodynamic instability or progressing to ventricular fibrillation in children with elevated ICP [5]. The spectrum of arrhythmias observed included SVT, PVCs, and pulseless VT. The temporal clustering of these arrhythmias with episodes of rising ICP highlights a critical yet often under-recognized neurocardiac interaction in pediatric neurocritical care.
The underlying pathophysiology likely involves disruption of the central autonomic network, particularly in the context of diffuse cerebral edema or posterior fossa lesions including Arnold Chairi malformations [4,6]. These pathologies exert mechanical pressure on the autonomic centers of the brainstem, potentially resulting in vagal overactivity (leading to bradyarrhythmias) or sympathetic overdrive (associated with tachyarrhythmias) [7]. Additionally, rapid ICP elevation may precipitate Cushing’s triad, hypertension, bradycardia, and irregular respiration through brainstem ischemia and the activation of the ventrolateral medullary pathways, as described by Fitch et al. [8].
All five children in this series exhibited clinical, sonographic, or radiologic indicators of increased ICP, including elevated ONSD, abnormal TCD indices, and high opening ICP values (ranging from 32 to 80 mm Hg) (Table 1). Arrhythmias appeared during phases of refractory ICP elevation despite tiered anti-ICP measures. These episodes were frequently associated with autonomic instability characterized by marked fluctuations in heart rate and blood pressure, which temporally correlated with ICP surges (Fig. 1) [3].
These observations align with the neurogenic arrhythmia hypothesis, wherein arrhythmias are associated with central nervous system dysfunction rather than that with primary cardiac disease or any dyselectrolytemia [9]. Chatterjee [10] described frequent ECG abnormalities, including VT, in adults with subarachnoid hemorrhage, attributable to central autonomic dysfunction. Pediatric data are limited; however, similar findings have been reported (Table 2) [6,10,11,12], with multiple types of arrhythmias arising from various etiologies. However, most of these studies did not include ICP values. Grosse et al. [11] reported a case of an 8-year-old patient with traumatic brain injury who developed VT during elevated ICP episodes and was unresponsive to antiarrhythmic therapy until the ICP was definitively managed [13].
In our series, as shown in Fig. 2, four children (cases 1–4) developed VT, with case 1 exhibiting frequent PVCs that preceded sustained VT. SVT was observed in two children (cases 2 and 5), one of whom (case 5) required synchronized cardioversion following adenosine failure. Notably, none of the patients had electrolyte disturbances, hypoxia, or structural cardiac anomalies, strongly suggesting that an increased ICP is a probable arrhythmogenic trigger.
Management was individualized based on the arrhythmia type and hemodynamic stability. Amiodarone was effective in three patients with VT, and lignocaine was added in one patient with VT. SVT responded to adenosine in one case but required electrical cardioversion in another [12,14]. Remarkably, in case 4, VT resolved spontaneously following successful ICP control, underscoring the central role of ICP in arrhythmogenesis. Hence, ICP reduction via cerebrospinal fluid diversion, osmotherapy, sedation, or decompressive surgery should be prioritized, with antiarrhythmics serving as supportive adjuncts rather than as primary therapy.
Clinical outcomes differed among the patients. Three children (cases 2, 3, and 4) survived with moderate ICP elevation and responded to medical management. In contrast, two children (cases 1 and 5) succumbed to multiorgan failure and refractory intracranial hypertension, both having severe ICP elevations (≥80 mm Hg) and profound autonomic instability, despite maximal therapy.
These findings highlight the fact that malignant arrhythmias with increased ICP may serve as potential indicators of brainstem compromise and impending herniation. The evolution from minor ECG changes to life-threatening VT calls for the early recognition of neurogenic triggers and aggressive ICP control. Continuous ECG and neuromonitoring, heightened awareness of neurocardiac complications, and timely neurosurgical collaboration are crucial to improving outcomes [15].
This study also underscores the need for integrated neurocardiac monitoring protocols in pediatric intensive care units. Recognizing the bidirectional communication between the brain and heart, particularly in critically ill children, may allow earlier intervention and better prognostication. Our experience emphasizes the need for structured bedside protocols in pediatric neurocritical care that incorporate continuous ECG and ICP monitoring, timely escalation of ICP therapies, rapid exclusion of systemic causes, and readiness for antiarrhythmic interventions. Nurse-led vigilance for autonomic instability with clear escalation pathways is vital to ensure timely, coordinated management, and improved outcomes.
This case series highlights that life-threatening arrhythmias, including both ventricular and SVTs, are critical and underrecognized manifestations of increased ICP in children. These arrhythmias often emerge in the context of autonomic instability, and may serve as clinical markers of brainstem herniation/involvement or refractory ICP. In such scenarios, prompt and effective ICP control remains the cornerstone of management, with antiarrhythmic therapy playing both supportive and adjunctive roles. The early identification of neurocardiac interactions through multimodal neuromonitoring combined with aggressive ICP-directed interventions may improve outcomes. However, the presence of refractory ICP and autonomic storms typically implies a poor prognosis. This series underscores the need for heightened awareness of the neurocardiac interplay in pediatric neurocritical care, where anticipation, timely recognition, and integrated management may be life-saving.