Heart failure occurs when the pumping capacity of the heart is compromised. It is a condition which the heart has trouble pumping blood because it has become weak or stiff; thereby decreasing its ability to meet the demand of the body’s need for oxygen and nutrients.
It is significant to understand that the symptoms of heart failure may be due to systolic dysfunction emanating from the right or left side of the heart, or may occur with preserved systolic function with symptoms due to the abnormal diastolic function of the heart. Systolic failure happens when the heart is not contracting well, meaning the blood can’t get out of the heart so the blood can’t get in because there is still blood in the heart. In diastolic failure, the blood can’t come into the heart because the ventricle is too thick and as a result of that, if the blood can’t come into the heart there is no blood to pump out causing HF. Heart failure can manifest in many ways, depending on how extent ventricular remodeling and dysfunction have advanced.
Heart failure may be discovered because of a known clinical condition such as MI or because decreased exercise tolerance, fluid retention, or admission to the critical care unit for an unrelated condition (https://www.clinicalkey.com/nursing/).