Heart Attack : a heart attack occurs when the supply of blood and oxygen to the area of the heart muscle is blocked usually by a clot in a coronary artery often, this blockage leads to arrhythmia s, innregular heartbeat or rhythm that causes a severe decrease in pumping of the heart function and may bring sudden death. If the blockage is not treated within a few hours the affected heart muscle will die and be replaced by scar tissue. Congestive heart failure (CHF) or heart failure is a condition in which the heart can t pump enough blood to the body s other organs, this is a result from: . primary diseases of the heart itself, called cardimyopathy .heart defects present at birth - congenital heart defects .Infections of the heart valves and/or heart muscle itself - endorcarditis and/or myocarditis .narrow arteries that supply blood to the heart muscle - coronery artery disease. .past heart attack, myocardial infection with scar tissue that interfers with the hearts muscle normal work .High blood pressure .heart valve disease due to past reheumetic fever or other causes. the failing heart keeps working but not as effciently as it should people with heart failure cant exert themselfs b/c short breath and tired. As blood flow out of the heart slows, blood is returning to the heart through the veins backs - up causing congestion in the tissue often swelling ( edema ) results most often in the legs, and ankles in other parts of the body also, sometimes fluid collects in the lungs interfers with breathing causing shortness of breath especially when a person is lying down. Heart failure also affects the kidneys ablity to dispose of sodium and water. The retainted water increases the edema.