Non-compaction (described but not classified by the World Health Organization (WHO))
In some references, takotsubo may be classified as a genetically passed on trait.
Secondary myocardial diseases may be reversible if the precipitating conditions are treated and resolved.
Secondary myocardial diseases are generally acquired (note: research is now identifying many diseases as having a genetic component) and their etiologies are:
Description of Primary and Secondary Causes
Diseases of the myocardium often fall into the "Big Three" forms of cardiomyopathies. Those are hypertrophic, dilated, and restrictive. The two other forms are arrhythmic and non-compaction which are not as common.
The chart describes the overall appearance of each pathology and possible outcomes.
Primary Myocardial Diseases - most common causes
A disorder of protein metabolism which results in protein deposition in the interstitial infiltration of the myocardium.
A granulomatous disease of unknown cause that results in an abnormal collection of inflammatory cells primarily found in the lungs and lymph nodes.
The term literally means "from unknown cause".
An autosomal dominant disorder that does not always progress to a pathologic stage.
The inability to produce insulin to control blood sugar leading to accumulation of lipids in the endothelial layers of blood vessels.
An abnormal growth of connective tissue which is believed to occur as a result of the body's immune system attacking healthy tissues.
A disease characterized by a persistently elevated eosinophil (a component of blood) count (≥ 1500 eosinophils/mm³) also known as Löffler's endocarditis.
A disease characterized by thickening and retraction of the tricuspid valve resulting in stenosis and regurgitation, pulmonic valve retraction and stenosis, right sided endocardial surfaces, and left sided cardiac valves (uncommon).
The right heart is mostly affected due to systemic tumor substances being inactivated by the lungs.
The histological assessment of the macroscopic and microscopic presence of scarring and interstitial plexiform (network-like) fibrosis.
The side effect of radiation therapy in the treatment of patients with cancer, can cause damage to the heart and pericardium.
The toxic effect of some drugs such as cocaine, glucocorticoids, lipid-lowering drugs, antimalarials, and colchicine can cause direct myotoxicity.
The spread of cancer cells, usually from the liver, cause growth inducing serotonin to spread to the heart leading to cardiac valves and tissues.
The abnormal accumulation of iron in parenchymal organs, leading to organ toxicity, and myocardial rigidity.
Genetic deficiency or absence of specific enzymes required for glycogen breakdown.
•• Most common causes of RCM
Specific determination of the forms of infiltrative processes are achieved by biopsy.
Classification and Description
Hypertension cardiomyopathy is due to systemic elevation of blood pressure and can be both inherited or acquired and presents as a abnormal thickening of the left ventricle with or without decreased ventricular dysfunction. This form of myocardial disease is also considered age related with some thickening over time.
Systemic elevation of blood pressure due to increased vascular resistance increases the workload on the heart causing changes in the size and number of myocites in cardiac muscle. The changes in cardiac thickness and dimensions cause structural abnormalities that can lead to electrophysiologic conduction aberrations, cardiac arrhythmias like atrial fibrillation, coronary artery disease, systolic and diastolic dysfunction, myocardial infarction, renal artery stenosis, and congestive heart failure.
The most commonly used are the Sokolov-Lyon criteria (S wave depth in V1 + tallest R wave height in V5-V6 > 35 mm).
ST elevation in the right precordial leads V1-3 (“discordant” to the deep S waves).
ST segment depression and T wave inversion in the left-sided leads
These criteria are often seen in left ventricular hypertrophy, however, overall evaluation of the heart must be performed in order to determine the root cause of such changes. Measurements may identify the diagnosis as mild, moderate, to severe disease.
Concentric global left ventricular thickening with "ground glass" appearance
Left atrial enlargement
Increased left ventricular mass
Preserved or enhanced global left ventricular function (early stage)
Left ventricular dilatation and reduced ejection fraction (late stage)
Increased left ventricular outflow tract velocities
"Dagger shaped" CW profile
Mitral valve E/A velocity
Possible presence of aortic regurgitation, mitral regurgitation
Morphological changes affect the mean LV-mitral valve angle leading to Doppler mitral inflow and also a greater mean value of LV-aortic root angle which affects flow through the LVOT.
Case study video showing concentric left ventricular hypertrophy from long standing hypertension.
Valvular insufficiency and/or stenosis etiologies pose different effects based on the conditions of the valves and their place in the cardiopulmonary system. The disease is hereditary and/or acquired.
Congenital valvular heart disease is a complex array of conditions that occur in the development of the heart beginning at embryogenesis. These conditions will be reviewed in the Congenital Heart Disease Series with the exception of congenital heart diseases in the adult patient.
Congenital bicuspid aortic valve presents with a normal annulus but commisural fusion, prominent raphae, and "football shaped" orifice in systole. Note: coarctation of the aorta is a co-morbidity in bicuspid aortic valve.
Acquired valvular disease is often due to infection, lifestyle, or heriditary conditions:
A patient with multi-valvular disease
Usually attributed to coronary artery disease, ischemia is due to atherosclerosis in the coronary arteries or in the microvasculature or other obstruction preventing adequate perfusion.
Ischemia may be due to long term coronary artery disease, acute coronary syndrome, or previous myocardial infarction or extensive ventricular remodeling.
The diagnosis lies in the medical history, signs and symptoms, and diagnostic tools such as blood chemistry, electrocardiography, magnetic resonance imaging, cardiac CT imaging, echocardiography, or angiography should the symptoms become severe.