Cardiac hypertrophy:
Hypertrophy occurs due to increased stress on the heart. It generally takes place in ventricles. The most common causes of heart thickening is increased blood pressure in either the lungs or the body. The extra work of pumping blood against the increased pressure causes the ventricle to thicken.
Hypertrophy are can be divided intoof two types:
1) Left ventricular hypertrophy (LVH)
2) Right ventricular hypertrophy (RVH)
1) Left ventricular hypertrophy
High blood pressure, or hypertension, is considered to be the most frequent cause of left ventricular hypertrophy (LVH). LVH can because due to Stenosis of the aortic valve. Stenosis does not allow the heart valve to open fully, thus preventing the pumping of the blood to lungs. Hypertrophic cardiomyopathy, a disease of the myocardium in which a portion of the myocardium is thickened without any obvious cause, are is some one of the most common causes of LVH. Hypertrophic cardiomyopathy is a genetic disease. These fibers need to work harder to pump blood and become thickened over time. Hypertrophic cardiomyopathy occurs in 1 in 500 people.
2) Right ventricular hypertrophy
Harmful lung Diseases such as emphysema and cystic fibrosis are some of the common causes of Right ventricular hypertrophy. These diseases are so fatal that it can even destroy the blood vessels present inside lung which can result in increased pressure in the remaining vessels. Chronic bronchitis and sleep apnea that occurs due to decrease in the level of oxygen also lead to Right ventricular hypertrophy (RVH). Stenosis of the pulmonic heart valve, primary pulmonary hypertension and repeated blood clots to the lungs (chronic pulmonary embolism) are the other causes of RVH that needs to be taken care of.
Cardiac dilation:
Cardiac dilation is also known as dilated (congestive) cardiomyopathy. In cardiac dilation, the heart becomes weak and doesn't pump blood normally becuasebecause the left ventricle, is enlarged and stiff. It can lead to congestive heart failure. Cardiac dilation is caused due to the direct damage to the heart muscle. These damages can be due to prior heart attack, heart muscle inflammation or can be due to long-term alcohol abuse. Heart muscle inflammation, which is also known as myocarditis, is sometimes of unknown cause and is often associated with a viral infection or interaction between the immune system and the heart muscle. Immune reaction can be observed with inflammatory diseases like lupus. It can also be noticed toward the end of pregnancy.
Dilation can also be caused due to cancer chemotherapy, hemochromatosis (iron accumulation), use of cocaine, and or exposure to metals like cobalt, lead, and mercury. Other sources that can lead to cardiac dilation are thyroid disease, diabetes, severe coronary artery disease, and or viral infections of the heart.