The heart which has always believed to be a symbol of life and love of joy and happiness of courage and faith is usually put through relentless abuse. Nevertheless it functions incessantly at its best capacity beating all odds. Hence in yoga we say that the heart can be thought of as a karma yogi - an individual who puts in the best effort in the task at hand expecting nothing in return. After all the pain that heart endures it starts showing warning signs which we ignore and then when it eventually starts giving put when are in a