As of 2010, heart disease has been the number one cause of death in America for nearly a century. In fact, the American Heart Association reports that one heart disease-related death occurs every 38 seconds. Heart disease refers to any disorder that disrupts the heart's ability to function efficiently. While the terms coronary artery disease and heart disease tend to be used interchangeably, coronary artery disease is only one form of heart disease. Heart disease can result not only from blocked coronary arteries, but also from congenital defects, toxins and infections.
Coronary Artery Disease
Coronary artery disease accounts for more than half of all cardiovascular diseases in the United States, according to 2010 American Heart Association statistics. Narrowing and hardening of the coronary arteries as a result of plaque build-up decreases blood flow to the heart muscle, leading to a heart attack. Heart attacks cause structural damage to the heart muscle and ultimately decrease the functional capacity of the heart to contract forcefully. Additionally, heart attacks can alter the rhythmic electrical impulses that stimulate the heart to beat. This disruption causes the heart to beat erratically and further decreases the heart's efficiency. These structural and functional changes are the basis for the development of heart failure.
Congenital Heart Disease
Congenital heart disease is the result of structural malformations of the heart and blood vessels at birth. The structural defect can vary in severity from small flaws that eventually resolve without surgical intervention, to major defects requiring multiple surgeries and continuous physician supervision to complete the repair. A 2010 report in Cardiovascular Pathology proposes five levels of classification for congenital heart disease based on the degree of structural abnormality and the resulting cardiovascular impairment. Advances in the treatment of congenital heart disease have increased the likelihood of patients surviving into adulthood. In 2009, American Heart Journal reported a greater than 50 percent decrease in the death rate for patients with the most common forms of congenital heart disease from 1973 to 2005.
Cardiomyopathy
Cardiomyopathy is a form of heart disease that causes inflammation of the heart muscle. The National Heart Lung and Blood Institute recognizes four major types of cardiomyopathy: dilated, hypertrophic, restrictive and arrhythmogenic right ventricular. While hypertrophic and arrhythmogenic right ventricular cardiomyopathies are generally considered inherited forms of heart disease, dilated and restrictive are acquired. Dilated cardiomyopathy is the stretching and thinning of the heart muscle, causing it to weaken. Commonly resulting from coronary artery disease, dilated cardiomyopathies can be caused by viral infections, toxins, cocaine and amphetamines, alcohol abuse, and complications during pregnancy. Restrictive cardiomyopathy causes the heart tissue to become stiff and rigid, preventing the heart from relaxing and filling with blood. Restrictive cardiomyopathies can be a toxic response to the build-up of iron or abnormal proteins in the body, or a result of an abnormally functioning immune system.
References
- "Circulation"; Heart Disease and Stroke Statistics 2010 Update; Donald Lloyd-Jones, M.D.; 2010
- "Cardiovascular Pathology"; Anatomical and Pathophysiological Classification of Congenital Heart Disease; Gaetano Thiene, M.D.; 2010
- "American Heart Journal"; Mortality Associated with Adult Congenital Heart Disease; Priya Pillutla, M.D.; 2009
- National Heart Lung and Blood Institute: Cardiomyopathy
