Why Heart Fails
Heart fails when the heart is unable to pump blood effectively. So, why does this happen? Now, let us look at the various causes of heart failure. The major causes of this failure, according to cardiologist, are coronary artery disease, high blood pressure, cardiomyopathy, and valvular heart disease.
First of all, excessive weight leads to increased blood volume in the body. This is only natural, since the excess body mass requires adequate blood flow, just like any other body tissue. However, this means the heart must continually pump a larger volume of blood. In other words, the workload of the heart is being increased; proportionally to the weight. Just like any other muscle in the body, the heart muscle responds to this increased workload by becoming hypertrophied, i.e. by increasing its size. This condition is called left ventricular hypertrophy (LVH), and is often associated with some degree of hypertension (increased blood pressure).
Up to a point, the heart can accommodate this and continue to function normally. Later however, the following problem develops: As the heart muscle grows larger, the coronary arteries (the vessels supplying blood to the heart muscle) fail to proliferate at the same rate. Although additional coronary branches are being formed, their number soon becomes insufficient to sustain the increased mass of the heart muscle. Therefore, a relative ischemia (lack of blood) occurs, which tends to become manifest during states of high demand (physical exercise, febrile illnesses, etc). The heart tissue affected by this phenomenon is being damaged over time, and gradually looses is ability to contract normally. Moreover, the hypertrophied cardiac muscle looses elasticity, and therefore fails to relax completely in between cardiac contractions. This cause’s insufficient filling of the heart muscle with blood prior to a contraction, which in turn decreases the amount of blood pumped out during the contraction. Resulting in heart failure.