What is the difference between stunned and hibernating myocardium?
Definitions: Stunned myocardium is viable myocardium salvaged by coronary reperfusion that exhibits prolonged postischemic dysfunction after reperfusion. Hibernating myocardium is ischemic myocardium supplied by a narrowed coronary artery in which ischemic cells remain viable but contraction is chronically depressed.
What is myocardial hibernation?
The term hibernating myocardium was first proposed by S. Rahimtoola in 1985 to describe a state of left ventricular dysfunction at rest caused by reduced coronary blood flow, which can be reversed by restoring myocardial oxygen supply or reducing myocardial oxygen demand.
How is myocardium hibernating diagnosis?
Hibernating myocardium has also been diagnosed by assessing contractile reserve, usually using echocardiography or magnetic resonance imaging (MRI) and low‐dose dobutamine. A region of the myocardium not initially contracting may contract when stimulated inotropically by low‐dose dobutamine.
How common is hibernating myocardium?
Between 20% and 50% of people with heart failure caused by coronary artery disease (CAD) may have a substantial amount of hibernating myocardium. Hibernating myocardium typically causes no discernible symptoms, although some people experience chest pain or shortness of breath.
How long does it take for stunned myocardium to recover?
In stunned myocardium, contractile function improved significantly at 3 months, without further improvement at 14 months; 61% of the stunned segments improved at 3 months, and 9% improved at 14 months.
How do you reverse myocardial ischemia?
Treatment for myocardial ischemia involves improving blood flow to the heart muscle. Treatment may include medications, a procedure to open blocked arteries (angioplasty) or bypass surgery. Making heart-healthy lifestyle choices is important in treating and preventing myocardial ischemia.
Why does myocardial stunning occur?
Predisposing factors for myocardial stunning include a history of left ventricular systolic dysfunction, male sex, higher left ventricular mass index, increased age, and higher ultrafiltration rates. Repetitive myocardial stunning may also predispose to development of permanent segmental abnormalities.
What causes a stunned heart?
Stunned myocardium is a condition of transient left ventricular dysfunction following an ischemic event to the myocardium. It occurs if coronary blood flow was impaired for a brief period of time (5 to 15 minutes).
What is stunned disease?
“Stunned” myocardium is myocardium that suffers transient reversible myocardial contractile dysfunction induced by acute ischemia wherein the blood supply is almost completely restored on reperfusion and suffers no metabolic deterioration.
What does a stressed heart mean?
Broken heart syndrome, also known as stress cardiomyopathy or takotsubo syndrome, occurs when a person experiences sudden acute stress that can rapidly weaken the heart muscle.
How is hibernating myocardium related to tracer uptake?
On F-18 FDG PET, hibernating myocardium demonstrates metabolism (tracer uptake) at levels equal or even more intense than the normal myocardium. Thus, on comparison of the two studies, hibernating myocardium is indicated by a perfusion metabolism mismatch (reduced perfusion but preserved metabolism).
Is the myocardium still viable after hibernating?
Hibernating myocardium is myocardial tissue that has reduced contractility due to poor perfusion, but remains viable. It is important as hibernating myocardium can recover normal contractility with revascularisation.
Which is a differential diagnosis of hibernating myocardium?
Differential diagnosis. Hibernating myocardium represents a viable target for revascularization and should be distinguished from infarcted myocardium, where an attempt to revascularize would be futile. myocardial ischaemia : rest images will demonstrate reversal of stress perfusion abnormality.
Why is hibernating myocardium important in ischemic heart disease?
In ischemic heart disease, evaluating myocardial viability is important because hibernating myocardium can recover function after revascularization. Hibernating myocardium is most commonly seen in the setting of chronic ischemia when myocardial cells adapt to longstanding poor perfusion by entering a state of low metabolic activity.