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Effect of Stroke on Heart, Diabetes and Hypertension 137

1.The various ECG changes seen in patients with patients with stroke. The pattern of myocardial dys-
stroke include: function in SAH patients is quite different from that
of a coronary artery disease because apical myocar-
Prolongation of the QT interval, repolarisation ab- dium is typically spared in patients with SAH. The
normalities like-ST segment depression or elevation, proposed mechanism for myocardial dysfunction is
inverted or flat T waves, new Q waves, bradyarrhyth- stroke related increase in myocardial catecholamine
mias, tachyarrhythmias
levels especially in the subendocardium resulting in
‘myocytolysis’ through a cascade of mechanisms.
These electrical changes can be further These myocardial necroses are concentrated around
classified into: the cardiac nerve endings and not in the vascular
territory as seen in coronary artery disease. Adding
1. Life threatening or potentially life strength to this is a study by Banti et.al, in which they
threatening compared echocardiogram, cardiac MIBG scintigrapy
Bradyarrythmias and tachyarrhythmia of all kinds can to assess the myocardial sympathetic innervations
be seen. The proposed mechanism is disturbed auto- and Technitium Sestabamibi scintigraphy to assess
nomic balance as a result of damage to the specif- the myocardial perfusion in patients with neurogenic
ic brain areas. Bradyarrhythmias are more common myocardial injury. In that study they observed cardi-
with right insular lesions and tachyarrhythmias with ac perfusion study to be normal in all the subjects
left sided lesions and animal studies have shown whereas MIBG scintigraphy abnormality was directly
that right insula has a preferential influence over proportional to the myocardial regional wall motion
sinuatrial node(fig.5). One could have a speculation abnormality scores and cardiac enzyme elevation.
that arrhythmia might be the cause for the stroke or The Left ventricular dysfunction observed in such
the stroke has unveiled a subclinical cardiac disease, cases is reversible. Treatment of the primary disease
but there is ample evidence to say arrhythmias are and its associated complication alone are needed in
seen even in patients without any evidence for cardi- such cases unless the ventricular dysfunction causes
ac disease or abnormality. Prompt identification and hemodynamic instability. An important clinical sce-
an appropriate early management are essential for a nario one might anticipate especially in patients with
favourable outcome. (1) sub arachnoid haemorrhage is ventricular dysfunc-
tion which might preclude the use of HHH therapy
2. Innocuous or possibly innocuous which will be counterproductive setting a vicious cy-
cle. When such is the case Intra aortic balloon coun-
This includes repolarisation abnormalities like devia- terpulsation can be used. Patients with subarachnoid
tion of the ST segment, U wave flattening / inversion hemorrhage who are brain dead are potential candi-
and prolongation of the QT interval .In few cases new dates for organ donation. But transient left ventricular
Q waves may be seen. The word “possibly innocu- dysfunction might preclude the donation of heart. A
ous” is used because QT prolongation may be a tran- study has specifically addressed this issue in which
sient finding without causing any hemodynamically they have observed that in 92% of such cases the
significant arrhythmias or at times it may be a har- heart resumed normal function following transplan-
binger for a life threatening arrhythmia. Most of these tation. (1)
findings are transient and will disappear over a period
of time without any treatment or causing any impact. Takotsubo cardiomyopathy: Named after Japanese
A point of caution here is, other possible causes of octopus trapping pot because the Left ventricular
such ECG abnormalities like dyskalemia must be angiogram of such patients resembles the pot. A
ruled out before tagging them as stroke related. special form of stress cardiomyopathy with apical
ballooning seen also in patients with subarachnoid
3. Structural abnormalities/ functional: haemorrhage.
Left ventricular dysfunction: This may be seen in
pre-existing coronary artery disease which is further 4. Biochemical:
worsened by the current stroke related stressors ( Cardiac enzyme abnormalities: Elevation of cardiac
as both of them share many risk factors) or de novo muscle enzymes namely Creatine kinase , Creatine
as evidenced in clinical studies wherein left ventric- kinase -MB, Troponin I are seen in both ischemic and
ular dysfunction have been documented in the pres- hemorrhagic stroke and correlates with the devel-
ence of normal coronary angiogram. Both regional opment of cardiac arrhythmias, Left ventricular dys-
and global l wall motion abnormalities are seen in function and severity of neurologic injury. Female

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