Heart disease or Cardiopathy is a broad term that covers a large range of diseases affecting the heart. As of 2007, it is the leading cause of death in the United States, England, Canada and Wales. It includes the following conditions:
Coronary Heart Disease
This disease involves an obstruction in the transport of blood in the Corony circulation, to the muscles and surrounding tissue that require its supply. It is often closely associated with Coronary Artery Disease which involves a build up of atheromatous plaques in the walls of the vessels that supply the myocardium. This can then go on to cause Angina (severe chest pain) due to restricted blood flow or more serious and sometimes fatal conditions such as a Myocardial Infaction (heart attack).
Myocardial Infarction (MI)
An MI occurs as a result of Coronary heart disease, atherosclerosis and the subsequent formation of a blood clot or thrombus. Once formed, a clot can completely occlude blood flow to a particular area of muscle, depriving it of oxygen and causing an accumulation of poisonous waste products; eventually leading to tissue death.
Cardiomyopathy is the deterioration of the heart muscle tissue itself; the myocardium. Patients with this disease are often at high risk of Arrythmias and sudden cardiac death. The most common cause of Cardiomyopathy is ischemia; a restriction in blood supply.
This condition can result from any structural or functional cardiac disorder, that negatively affects the heart’s abilty to fill its chambers or to pump blood around the body effeciently. This leads to heart and therefore body failure.
Hypertensive Heart Disease
Hypertensive heart disease is caused by hypertension; an elevation in systemic arterial blood pressure above the normal level of 120 mmHg. It can lead to more serious conditions such as heart failure, arrythmias, coronary heart disease and left ventricular hypertrophy.
When there is a problem with the heart’s electrical conduction system, it results in an arrhythmia; a rhythm disorder that creates an irregular heartbeat. Normally the heart beats 60-100 times per minute and in this state it is known as ‘normal sinus rhythm.’ Depending upon the requirements of the body at a particular time, the heart may beat faster, Sinus Tachycardia due to an increase in stress levels, or slower, Sinus Bradycardia as seen during sleep.
There are various forms of Arrhythmias, classified mainly due to place of origin: the atria, AV node or ventricles.
· Ventricular Arrhythmias arise from the ventricles
· Supraventricular Arrhythmias originate from the AV node or atria
Although Heart disease often causes arrhythmias, having an arrhythmia does not necessarily mean a patient has Heart disease. They often have many causes, some of which remain unknown. These include:
· Infection or fever
· Physical or emotional stress
· Diseases such as Anemia or Thyroid disease
· Drugs and other stimulants such as caffeine, tobacco, alcohol, cocaine, amphetamines and certain over the counter medications.