Cardiomyopathy, heart defects, and hypertension are the main causes of enlargement of the ventricles. At the root of all of these conditions is the overworking of the heart, which consists of the blood pumping faster and results in the ventricular system's expansion. The cardiac enlargement develops so the heart can accommodate the amount of blood coursing through it.
In cardiology, the heart is comprised of four sections, or chambers. These are two chambers on top and two on the bottom. The lower chambers are made up of the left and right ventricles and pump blood to the upper chambers, the area known as the atria. Each ventricle has a specific duty. The left ventricle delivers oxygen-rich blood to the body via the aorta, while the right ventricle pumps blood that is weak in oxygen into the lungs via the pulmonary veins. When blood is forced to pump through the ventricles at a faster rate, they naturally expand to adapt to the flow, which can be caused by several factors.
The main factor is hypertropic cardiomyopathy (HCM), often referred to as simply cardiomyopathy. HCM attacks and thickens the heart muscle and causes the left ventricle to become rigid; it also institutes valve and cellular changes. These cellular changes directly affect the left ventricle during the thickening of the heart muscle. The ventricle cannot fully contract as it normally would, and is therefore unable to fill with healthy amounts of fresh blood. As a result, a lower amount of oxygenated blood is delivered to the aorta and pressure rises inside the heart.
Heart defects are another major cause of enlargement of the ventricles. These are birth defects that may or may not be evident from infancy. Heart defects can affect the ventricles of the heart by tampering with the normal, healthy flow of blood through the cardiovascular system.
Enlargement of the ventricles is also frequently caused by pulmonary hypertension. Hypertension is a form of high blood pressure within the heart and lungs. The condition has its source in the pulmonary arteries and capillaries of the lungs, which become restricted and thus unable to provide healthy blood flow into the lungs. The lungs, in turn, have to work harder to get sufficient blood, which causes pressure on the right ventricle of the heart. The right ventricle automatically enlarges to create space for this extra pressure being exerted on it, resulting in enlargement of the ventricles.
