Your heart fails when it can no longer service the needs of your body. Your heart can certainly fail due to problems within the heart itself. But it can also fail if problems outside of the heart do not allow it to properly function. It can be a sudden failure, or it can take a period of time, getting progressively worse.
Hypertension
You are diagnosed as having hypertension if your blood pressure reading is at least 140/90 on three separate occasions. According to William Graettinger, M.D., chief of the Division of Cardiology at the University of Nevada School of Medicine, approximately 62 million people are thought to have hypertension, but only 70 percent of them have actually been diagnosed. Your heart has four chambers; the two upper chambers are called atria and the two lower chambers are called ventricles. Your left ventricle pumps blood from your heart to circulate throughout your whole body. Hypertension can lead to heart failure because the high blood pressure forces your heart to work harder, especially your left ventricle. Working harder will make it thick, but weak. It won't function properly and eventually will fail to function at all.
Myocardial Infarction (MI)
The muscle layer of your heart is called your myocardium. An infarction is when part of an organ or tissue dies because it stopped getting enough blood. So, a myocardial infarction (MI) is when part of your heart muscle is damaged because it stopped receiving the blood and oxygen it needed. This usually happens because your coronary arteries have atherosclerotic plaques; areas of fat and cholesterol deposits with a "cap" that has formed over them. A blood clot breaks away from the plaque, blocks the flow of blood and causes the infarct. The damage can lead to heart failure. As of 2007, 400,000 to 500,000 people died from a MI, according to James Warnica, M.D., professor of medicine at the University of Calgary.
Myocarditis
Myocarditis is the inflammation of your myocardium. It can be due to various causes, but Thomas Bashore, M.D., writes in "Current Medical Diagnosis & Treatment" that the most common cause for myocarditis is infection by the coxsackie B virus. You may not have any symptoms at first. But then, you may feel tired and have difficulty breathing. You may have sudden heart failure or it may develop gradually over a period of time, getting progressively worse.
Endocarditis
Endocarditis is the inflammation of your heart's endocardium layer, which includes the valves. Blood in the right side of your heart must pass through valves to get to the lungs to pick up oxygen. Blood in your heart's left side passes through valves to exit the heart to circulate throughout your body. If the damage to a valve is severe enough, usually a valve in the left side, then your heart can fail.
References
- "Current Diagnosis & Treatment: Cardiology"; Michael Crawford, M.D.; 2009
- "Current Medical Diagnosis & Treatment 2009"; Stephen McPhee, M.D., Maxine Papadakis, M.D.; 2009
- The Merck Manual: Acute Coronary Syndrome
