What is Myofibrillar disarray?

What is Myofibrillar disarray?

Myocardial disarray, also known as myocyte disarray, is a term to describe the loss of the normal parallel alignment of myocytes (the muscle cells of the heart). Instead, the myocytes usually form circles around foci of connective tissue.

What is a myocyte disarray?

Myocyte disarray is characterized by architectural disorganization of the myocardium in which adjacent hypertrophied myocytes are aligned perpendicularity or obliquely to each other around the central core of collagen in a pinwheel configuration.

What is myocyte hypertrophy?

Abstract. One of the most controversial problem in cardiac muscle pathology is the existence of myocyte hyperplasia. The term hypertrophy indicates an increase in size of the individual muscle cells without changing their total number, whereas in hyperplasia there occurs proliferation of the myocyte.

What is cardiac hypertrophy?

Cardiac hypertrophy is an adaptive response to pressure or volume stress, mutations of sarcomeric (or other) proteins, or loss of contractile mass from prior infarction. Hypertrophic growth accompanies many forms of heart disease, including ischemic disease, hypertension, heart failure, and valvular disease.

What causes myocardial fibrosis?

Coronary heart disease, aortic stenosis and hypertension are the most frequent causes of myocardial fibrosis (13). Aortic stenosis and hypertension result in pressure overload of the left ventricle where the increased wall stress induces hypertrophy and interstitial fibrosis (2–4).

What causes myocyte disarray?

CONCLUSIONS—Myocyte disarray is probably a direct response to functional or structural abnormalities of the mutated sarcomeric protein, while fibrosis and small vessel disease are secondary phenomena unrelated to disarray, but modified by factors such as left ventricular mass, sex, and perhaps local autocrine factors.

What is the function of myocytes?

The muscle myocyte is a cell that has differentiated for the specialized function of contraction. Although cardiac, skeletal, and smooth muscle cells share much common functionality, they do not all share identical features, anatomical structures, or mechanisms of contraction.

What happens to myocytes in MI?

Significant numbers of myocytes die by apoptosis during myocardial infarction. The molecular mechanism of this process, however, remains largely unexplored. To facilitate a molecular genetic analysis, we have developed a model of ischemia-induced cardiac myocyte apoptosis in the mouse.

What are the two types of hypertrophy?

There are two types of muscular hypertrophy:

• myofibrillar: growth of muscle contraction parts.
• sarcoplasmic: increased muscle glycogen storage.

How is cardiac hypertrophy achieved?

Or, to put it in simpler terms: it is an increase in cardiac muscle mass when cardiac muscle fibers thicken, or cells become enlarged, due to chronic and increased stress on the heart.

What are the symptoms of cardiac fibrosis?

The lungs and the lymph glands between the lungs are frequently affected, and symptoms may include coughing and difficulty breathing. The heart may also be affected, resulting in abnormal heartbeat patterns (conduction block, atrial arrhythmia or ventricular arrhythmia) and/or heart failure.

How is myocardial fibrosis diagnosed?

Myocardial biopsies are taken from explanted hearts or during myectomy, open heart surgery or catheter-based endocardial biopsy. With heart biopsies and using appropriate staining methods, histological analysis of the volume fraction of collagen is regarded as the gold standard for detection of fibrosis (7, 10, 17).