Classic manifestations on EKG of the so-called cerebrovascular accidents, (most commonly associated with subarachnoid hemorrhage or other intracranial bleeds) are symmetrically and deeply inverted giant T waves.

The mechanisms are not fully delineated but may relate to excessive catecholamine stimulation causing direct myocardial injury (myocytolysis).

The ECG may be notable for marked QT-U prolongation (sometimes a giant U wave appears to be embeded in the T wave, creating a slight discontinuity in the waveform morphology). The long QT-U may predispose to torsade(s) de pointes. Takostubo syndrome may occur in some cases. Apical hypertrophic cardiomyopathy (Yamaguchi’s syndrome) is associated with deep narrow (spade-like) T wave inversions, most marked in the mid-precordial leads.

1. EKG changes seen in 71.5% of patients with subarachnoid hemorrhage, and 57.1% of those with cerebral hemorrhage.
2. Most common abnormalities are
   • Large, upright, or deeply inverted T waves
   • Prolongation of the QTc interval
   • Prominent U waves
3. Can persist for 11 days
4. Rarely can ST segment elevation or depression
5. Rhythm disturbances
   • Sinus bradycardia
   • Sinus tachycardia
   • Wandering atrial pacemaker
   • AV junctional rhythm
   • Premature ventricular contractions PVCs
   • Ventricular tachycardia (VT)
6. Reason for changes is thought to be altered autonomic tone

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  Patient with subaracnoidal hemorrhage
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  EKG of a patients with CNS Disorders
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  Inverted and deep T waves in the precordal leads due to subaracnoidal aneurysm [Image courtesy of Dr Jose Ganseman Dr Ganseman’s webpage: An ultimate source of EKG

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