Editing Hibernating myocardium

{{Short description|State when some segments of the myocardium exhibit abnormalities of contractile function}}
In [[cardiology]], '''hibernating myocardium''' is a state when some segments
of the [[myocardium]] exhibit abnormalities of contractile function.<ref name="pmid9664095">{{cite journal |vauthors=Wijns W, Vatner SF, Camici PG |title=Hibernating myocardium |journal=N. Engl. J. Med. |volume=339 |issue=3 |pages=173–81 |date=July 1998 |pmid=9664095 |doi= 10.1056/NEJM199807163390307|url=http://content.nejm.org/cgi/pmidlookup?view=short&pmid=9664095&promo=ONFLNS19|url-access=subscription }}</ref> These
abnormalities can be visualised with [[echocardiography]],  [[cardiac magnetic resonance imaging]] (CMR), nuclear medicine (PET) or [[Cardiac ventriculography|ventriculography]].
Echocardiography: A wall motion abnormality at rest which improves during a low-dose dobutamine stress test is classified as "hibernating myocardium." Low dose dobutamine stimulates contractile function and thus helps to predict functional recovery after revascularization.
Cardiac magnetic resonance: The most frequently used MR [[contrast agent]]s based on Gd-chelates accumulate in the extracellular space which is increased in scarred myocardium. This leads to a signal increase which can be visualised with the "late gadolinium enhancement technique." This is probably the most accurate way to visualise scarred myocardium. An alternative (or additional) technique with CMR is the use of low dose dobutamine similar to echocardiography.
PET: The finding of a perfusion or metabolic mismatch between PET-FDG and PET-NH<sub>3</sub> is indicative of decreased metabolism. The wall of the affected segments is hypo-, a-, or dyskinetic.{{cn|date=February 2021}}

The phenomenon is highly significant clinically because it usually manifests itself in the setting of chronic [[ischemia]], that is potentially reversible by [[Revascularization|revascularisation]] via cardiac catheterization. The regions of myocardium are still viable and can return to normal function. There develops a new steady state between myocardial blood flow (MBF) and myocardial function, MBF reduced and in consequence function is reduced too. The clinical situations where one can expect hibernating myocardium are:{{cn|date=February 2021}}
* chronic stable [[Angina pectoris|angina]]
* unstable angina
* silent ischemia
* after [[myocardial infarction|AMI]]

==See also==
* [[Stunned myocardium]]
* [[Myocardial scarring]]

==References==
{{Reflist}}

{{Heart diseases}}

[[Category:Ischemic heart diseases]]

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