The ABCs of heart disease

Gene Therapy: This heart therapy involves inserting altered genes into dead or unresponsive heart muscle to stimulate the growth of newer blood vessels. Canada entered the competitive gene-therapy research fray when the Heart & Stroke/Richard Lewar Centre of Excellence opened. This multimillion-dollar center focuses on developing novel gene-based approaches to diagnosing and treating two of the most important heart-related problems facing Canadians: hardening of the arteries and heart failure.

Hormone Replacement Therapy: Research once suggested that HRT significantly lowered the risk of heart disease in post-menopausal women. Unfortunately that is no longer the case. The Heart and Stroke Foundation now recommends that women with pre-existing heart disease avoid HRT and that young, healthy women not embark on HRT solely for the prevention of heart disease. Although HRT does help protect against osteoporosis and offers relief of menopausal symptoms, if you are approaching menopause and do not suffer from heart disease, the risks may still be greater than the benefits. Discuss your options with your doctor.

Inflammation: What makes some people with normal blood cholesterol levels drop dead of a heart attack? It might be due to low levels of inflammation attacking the heart. It has been proven that hardening of the arteries, or atherosclerosis, is an inflammatory disease like arthritis. In both cases the disease is the immune system's response to an injury. With arthritis the body attacks its own joints; with inflammatory heart disease its focus is the coronary arteries. In response to an injury in the wall of the artery, possibly caused by high blood cholesterol or smoking, the immune system mounts an inflammatory response that may lead to the rupture of plaque buildup in the artery. Doctors can now measure inflammation, using a simple blood test, to determine who is prone to a heart attack.

J-Curve phenomenon: Blood cholesterol that is too high is linked to heart disease, but so is cholesterol that is too low. This phenomenon, when illustrated on a graph that plots the cholesterol levels in large groups of people against mortality from heart disease, often appears as a J-shaped curve. The curve shows that those with the higher levels of cholesterol closer to the top of the curve are more likely to die from heart disease. However, it also shows that those with the lowest cholesterol also have increased heart-related mortality. This phenomenon does not mean that lowering cholesterol is harmful. Normal cholesterol treatments do not cause the abnormally low levels associated with increased mortality. The same J-curve phenomenon can be seen with high blood pressure.

Kawasaki Disease: This mysterious illness, characterized by fever, rash and swelling of hands and feet and other areas of the body, affects mostly young children. It's a leading cause of heart disease in these kids; in as many as 20 per cent of them, the heart is affected.