myocardial disarray
Abnormal arrangement of cardiac muscle fibers characterized by loss of normal parallel alignment, often associated with hypertrophic cardiomyopathy.
Full Definition
Myocardial disarray refers to the loss of normal orderly arrangement of cardiomyocytes, which typically run in parallel bundles. In disarray, muscle fibers intersect at abnormal angles, creating a characteristic whorled or chaotic pattern on histological examination. This finding is most commonly associated with hypertrophic cardiomyopathy, where it affects more than 5% of the myocardium, but small amounts may be seen in normal hearts, particularly around the ventricular septum. The degree of disarray correlates with the risk of sudden cardiac death in hypertrophic cardiomyopathy. Special attention to tissue orientation during processing is required for accurate assessment.
Usage
Usage note: Quantification requires careful attention to tissue orientation and sectioning artifacts.
In Context
- "Extensive myocardial disarray involving 15% of the septum confirmed the diagnosis of hypertrophic cardiomyopathy." — endomyocardial biopsy report
- "The autopsy revealed significant myocardial disarray in the interventricular septum, consistent with the patient's known hypertrophic cardiomyopathy." — sudden death autopsy report