subendokardielle

Subendokardielle, often rendered as subendocardial in English, refers to the region of the heart muscle located just beneath the endocardium, the innermost lining of the heart chambers. It represents the inner portion of the myocardial wall, between the endocardium and the deeper layers of myocardium.

The subendocardial layer is particularly susceptible to ischemia, because coronary blood flow is most vulnerable during systole and the intramyocardial pressure may impede perfusion. Injury to this layer can occur in the setting of partial occlusion of a coronary artery, microvascular dysfunction, or systemic hypotension, and it may affect only a portion of the wall thickness.

In clinical cardiology, subendocardial infarction is non-transmural, meaning it does not involve the full thickness of the ventricular wall. It is often associated with non-ST elevation myocardial infarction (NSTEMI) or non-occlusive ischemia. Electrocardiography may show ST-segment depression and T-wave inversions rather than the ST elevation typical of transmural infarction. Cardiac biomarkers, such as troponin, may be elevated. Imaging, including cardiac MRI with late gadolinium enhancement, can reveal a subendocardial pattern of scar or necrosis.

Diagnosis and management hinge on recognizing ischemic risk and coronary event severity. Treatment generally follows NSTEMI guidelines: antiplatelet therapy, anticoagulation, nitrates, beta-blockers, statins, and risk-factor modification, with consideration of coronary revascularization when appropriate.

Etymology traces the term to Latin for “under the endocardium.” The concept is important for understanding patterns of ischemic injury and infarction within the heart wall.