müokardi

Müokardi, also known as the myocardium, is the muscular middle layer of the heart wall, located between the endocardium and the epicardium. It is composed of cardiac muscle tissue (cardiomyocytes) organized into irregularly arranged sheets that enable the heart to contract in a coordinated manner. The müokardi accounts for most of the heart’s mass and its contraction generates the force needed to pump blood through the circulatory system.

Structure and function: Cardiomyocytes are striated, involuntary cells linked by intercalated discs that contain gap junctions and desmosomes. This network supports rapid electrical coupling and synchronized contraction. The left ventricle typically has the thickest müokardi because it must generate the greatest force to propel blood systemically. The muscle relies on a rich vascular supply and abundant mitochondria, reflecting high metabolic demands.

Circulation and metabolism: The müokardi receives blood supply from the coronary arteries, with perfusion primarily occurring during diastole. It has a high capillary density and substantial fatty acid and glucose metabolism to meet energy needs. Oxygen deprivation or supply-demand mismatch can lead to myocardial injury.

Clinical significance: Diseases of the müokardi include myocardial infarction (ischemic injury due to blocked coronary arteries), myocarditis (inflammation of the muscle), and cardiomyopathies (such as dilated or hypertrophic forms) that impair contraction or relaxation. Arrhythmias can arise from disturbed electrical continuity within the müokardi or its conduction system. Diagnostics include ECG, cardiac troponin levels, echocardiography, and cardiac MRI. Treatments target restoring blood flow, reducing workload, managing symptoms, and preventing further damage.

Development and regeneration: The müokardi has limited regenerative capacity in adults. Injury often results in fibrous scar formation rather than complete tissue replacement, underscoring the importance of prevention and early intervention in ischemic heart disease and related conditions.