Cerebral T Waves in ECG

Cerebral T Waves in ECG

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1. What is the classical morphological feature of a cerebral T wave on ECG?

A. Tall, peaked T waves
B. Flattened T waves
C. Deep, symmetrical, inverted T waves
D. Biphasic T waves
✅ Correct Answer: C
Explanation: Cerebral T waves are typically deep, symmetrical, and inverted, often found in precordial leads. They are suggestive of increased intracranial pressure or acute CNS insult.

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2. Cerebral T waves are most commonly seen in which ECG leads?

A. Leads I and aVL
B. Inferior leads
C. Precordial leads V1–V6
D. aVR and aVL
✅ Correct Answer: C
Explanation: The precordial leads, especially V1–V4, are most commonly affected and show deep T wave inversions in cerebral T waves.

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3. Which of the following is a typical clinical scenario where cerebral T waves may be observed?

A. Pulmonary embolism
B. Acute ischemic stroke
C. Aortic stenosis
D. Hyperkalemia
✅ Correct Answer: B
Explanation: Acute ischemic stroke, especially involving large vessels like MCA, may produce cerebral T waves due to neurocardiogenic effects.

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4. What is the proposed mechanism for cerebral T wave changes?

A. Coronary vasospasm
B. Electrolyte imbalance
C. Neurogenic myocardial stunning
D. AV node dysfunction
✅ Correct Answer: C
Explanation: Neurogenic myocardial stunning caused by increased sympathetic stimulation during acute brain injury leads to T wave changes.

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5. Which of the following CNS events is least likely to cause cerebral T waves?

A. Subarachnoid hemorrhage
B. Intracerebral hemorrhage
C. Acute spinal cord injury
D. Large ischemic stroke
✅ Correct Answer: C
Explanation: While brain injuries often cause cerebral T waves, spinal cord injury is less likely to directly induce neurogenic ECG changes.

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6. What differentiates cerebral T waves from ischemic T wave inversions?

A. T wave morphology
B. Associated ST elevation
C. Symmetry and distribution of T wave inversions
D. Timing of appearance
✅ Correct Answer: C
Explanation: Cerebral T waves are typically deep, symmetrical, and diffuse, while ischemic T inversions are often asymmetrical and localized to the ischemic area.

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7. Which of the following ECG abnormalities may accompany cerebral T waves?

A. QT prolongation
B. J-point elevation
C. Short PR interval
D. U waves
✅ Correct Answer: A
Explanation: QT prolongation may be observed alongside cerebral T waves due to autonomic dysfunction.

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8. In the setting of stroke, cerebral T waves are a predictor of:

A. Seizure activity
B. Brain herniation
C. Cardiac arrhythmias
D. Cerebellar infarction
✅ Correct Answer: C
Explanation: These ECG changes are associated with an increased risk of cardiac arrhythmias in the setting of acute neurologic injury.

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9. The presence of cerebral T waves can mimic which cardiac condition?

A. Pericarditis
B. Anterior myocardial infarction
C. Left ventricular hypertrophy
D. Brugada syndrome
✅ Correct Answer: B
Explanation: The T wave inversions can mimic anterior MI, making clinical correlation and neuroimaging essential in stroke patients.

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10. Which condition must be excluded before attributing T wave inversion to a cerebral cause?

A. Left atrial enlargement
B. Myocardial ischemia
C. Bundle branch block
D. Atrial fibrillation
✅ Correct Answer: B
Explanation: Myocardial ischemia is the most common cause of T wave inversion and must be ruled out before labeling them as cerebral T waves.

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11. The timing of cerebral T waves typically corresponds to which phase of a stroke?

A. Pre-ictal phase
B. Acute onset
C. Recovery phase
D. Chronic phase
✅ Correct Answer: B
Explanation: These changes occur early during the acute phase of a stroke or CNS insult.

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12. Which part of the brain is most associated with neurocardiogenic ECG changes?
A. Occipital cortex
B. Hypothalamus
C. Parietal lobe
D. Cerebellum
✅ Correct Answer: B
Explanation: The hypothalamus regulates autonomic function and can mediate the neurogenic cardiac effects that cause ECG abnormalities.

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13. In which hemorrhagic CNS condition are cerebral T waves most prominently noted?

A. Epidural hematoma
B. Subdural hematoma
C. Subarachnoid hemorrhage (SAH)
D. Intramedullary hemorrhage
✅ Correct Answer: C
Explanation: SAH is classically associated with dramatic ECG changes including cerebral T waves, due to catecholamine surge.

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14. Which diagnostic tool is essential when cerebral T waves are suspected?

A. Coronary angiography
B. Brain imaging (CT or MRI)
C. Electrophysiologic study
D. Holter monitor
✅ Correct Answer: B
Explanation: Neuroimaging is critical to identify the underlying neurologic cause of the T wave abnormalities.

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15. What is the implication of cerebral T waves in stroke patients?

A. Predicts a smaller infarct size
B. Benign finding
C. Marker of poor prognosis
D. Indicates hemorrhagic conversion
✅ Correct Answer: C
Explanation: Their presence is associated with more severe stroke and higher likelihood of complications like arrhythmias.

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16. What role do catecholamines play in cerebral T waves?

A. Inhibit myocardial depolarization
B. Increase vagal tone
C. Induce myocardial repolarization abnormalities
D. Reduce cardiac output
✅ Correct Answer: C
Explanation: Excess catecholamine release from CNS injury alters myocardial repolarization, leading to T wave inversion.

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17. A 70-year-old with right-sided weakness shows deep T inversions in V2–V6. Troponins are normal. Next best step?

A. Cardiac catheterization
B. Repeat troponin in 12 hours
C. Urgent brain imaging
D. Treat as STEMI
✅ Correct Answer: C
Explanation: In the absence of biochemical evidence of MI, brain imaging is warranted to rule out acute stroke.

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18. Which of the following is not part of the differential diagnosis of cerebral T waves?

A. Takotsubo cardiomyopathy
B. Early repolarization
C. Wellen’s syndrome
D. CNS hemorrhage
✅ Correct Answer: B
Explanation: Early repolarization causes ST elevation but not deep symmetrical T wave inversions.

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19. Which population is most at risk for developing cerebral T waves?

A. Elderly with atrial fibrillation
B. Patients with epilepsy
C. Patients with acute CNS insults like stroke or SAH
D. Diabetics with neuropathy
✅ Correct Answer: C
Explanation: Acute brain injuries such as stroke and subarachnoid hemorrhage are high-risk scenarios.

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20. Which ECG change typically resolves with recovery from stroke or CNS insult?

A. PR prolongation
B. Cerebral T wave inversion
C. RBBB pattern
D. Q wave formation
✅ Correct Answer: B
Explanation: Cerebral T waves are usually reversible and resolve as the brain injury recovers or is managed.

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Cerebral T Waves in ECG

Cerebral T Waves in ECG

#	Point
1	Definition Cerebral T waves are deep, symmetrical, inverted T waves seen in the ECG, usually related to acute central nervous system (CNS) events.
2	Classic Leads Affected Most commonly seen in precordial leads V1–V6, especially V3–V5.
3	Morphology T waves are typically deep, symmetrical, and inverted — sometimes >10 mm depth.
4	Common Causes Subarachnoid hemorrhage, large ischemic strokes, and intracerebral hemorrhage.
5	Mechanism Catecholamine surge and neurogenic myocardial stunning following brain injury.
6	Associated ECG Changes QT prolongation, ST depression, U waves, and possible arrhythmias.
7	Neuroanatomy Link Hypothalamus and insular cortex are responsible for autonomic cardiac modulation.
8	Clinical Mimic Can mimic anterior myocardial infarction (MI), especially STEMI.
9	Important Differential Wellen’s syndrome – also causes deep anterior T inversions but is cardiac in origin.
10	Resolution Usually resolves within days to weeks as CNS injury improves.
11	Clinical Implication May indicate severe CNS pathology and predict worse neurologic outcomes.
12	Risk of Arrhythmia These patients are at higher risk for ventricular arrhythmias and sudden cardiac death.
13	Stroke Type Association More commonly associated with large vessel strokes like MCA infarctions.
14	Timing of Appearance Occurs early in the course of acute neurologic insult.
15	Troponin Levels May be mildly elevated due to neurogenic myocardial injury without true ischemia.
16	False Diagnosis Risk Misinterpreting cerebral T waves as MI can lead to inappropriate anticoagulation.
17	Additional Monitoring These patients often need cardiac telemetry and QT monitoring.
18	Diagnosis Confirmation Requires clinical context and neuroimaging (CT/MRI brain) for confirmation.
19	Reversibility Changes are typically transient and non-ischemic, reversible with treatment of CNS insult.
20	Take-Home Message Always correlate ECG findings with neurologic symptoms to avoid misdiagnosis.