Friday, December 16, 2011

Catching heart disease early

Medical illustration by Patrick J Lynch  

 

Heart disease consists of a number of conditions that affect the heart, including coronary artery disease, congestive heart failure, and hypertension. The early stages of these heart diseases are different, but they have similar effects on the body if left untreated – heart failure.

 

Early stages of coronary artery disease

 

Coronary artery disease is what most people mean when they say “heart disease”. This condition results from the accumulation of fatty deposits, called plaques, in the arteries bringing blood to the outer wall of the heart muscle. These plaques gradually block the blood’s pathway in the vessel, preventing oxygen and nutrients from getting to a portion of the heart (called ischemic heart disease). 

 

Atherosclerosis, which can be caused by high cholesterol, is one underlying cause. Plaque formation causes other kinds of heart disease, too, such as aneurysms, and the condition is exacerbated by hypertension. Because of this underlying association, high cholesterol levels are one early stage of coronary artery disease.

 

Sometimes there are no other signs or symptoms that the coronary arteries are being blocked. A person can have a heart attack or even sudden cardiac death without warning. However, in many people, as the arteries become clogged and the amount of oxygen getting to the muscle decreases, pain may be felt. These chest pains are called angina. The earliest onset of angina is stable angina – shortness of breath, chest pressure, and sweating upon exertion – and it is not yet to the stage of permanently damaging the heart muscle. A test is available to determine the extent of artery blockage in individuals with suspected stable angina in order to prevent unstable angina (the symptoms occurring at any time) and the unpredictability that brings in regards to heart attack or heart failure, but research in 2008 found that it is greatly underused.

 

Early stages of hypertension

 

Hypertension is the presence of consistently high arterial blood pressure – so the earliest stages of this disorder involve elevated blood pressure readings. A disorder known as pre-hypertension (blood pressure between 120/80 mmHg and 139/89 mmHg) is now recognized by medical professionals as a way to identify patients who are likely to develop hypertension if something is not done to stabilize their blood pressure. Pinpointing at-risk individuals early is key because hypertension, which is known as the “silent killer”, generally does not have any symptoms until damage occurs to the heart.

A number of mechanisms are involved in the development of this heart disease depending on the individual, as the disease can be genetic or diet and lifestyle related – cigarette smoking, high cholesterol, a family history of the disease, diabetes, obesity, lack of exercise, and high salt intake have all been linked to high blood pressure. It is also an age-related disorder because over time the body’s regulatory functions become less efficient. Research is still trying to determine why hypertension is so prevalent among the elderly.

 

Early stages of congestive heart failure

 

Congestive heart failure occurs when the heart is not working properly. It is due to damage from other heart diseases, such as ventricular hypertrophy caused by hypertension or scarring caused by heart attacks. Blood begins to back up and fluid swells the tissue spaces (called edema, and thus the term “congestive”). The lack of blood flow can cause pooling in the extremities (swollen ankles, hands, or feet) and fatigue. Once shortness of breath and regular coughing occurs, the disorder is past the early stages.

 

Early stages of other forms of heart disease

 

In addition to the signs mentioned above, the early stages of heart disease can include cyanosis, palpitations, and fainting.

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