myocardial stunning
Temporary mechanical dysfunction of viable myocardium following brief ischemia, despite restoration of normal perfusion.
Full Definition
Myocardial stunning represents a reversible form of myocardial dysfunction that occurs when viable heart muscle exhibits prolonged contractile abnormalities following transient ischemia, even after restoration of normal coronary blood flow. This phenomenon is commonly observed in cardiovascular surgery following cardioplegic arrest and reperfusion. Unlike myocardial necrosis, stunned myocardium retains metabolic activity and cellular viability, with function typically recovering over hours to days. Recognition of this condition is important for postoperative management and distinguishing it from irreversible myocardial damage.
Usage
Usage note: Distinguish from hibernating myocardium, which occurs with chronic hypoperfusion.
In Context
- "The patient exhibited myocardial stunning with gradual improvement in ventricular function over the first postoperative week." — Postoperative echocardiography report
- "Delayed recovery of contractile function was attributed to myocardial stunning rather than perioperative infarction." — Cardiology consultation note