>The end result is a progressively increasing blockage to blood flow through the vessel. Many factors contribute to the development of coronary atherosclerosis: a diet high in fat and cholesterol, smoking, hypertension, increasing age and family history. Women of reproductive age are generally at a lower risk due to the protective effects of estrogen. In the United States and other industrialized countries, coronary artery disease is the leading cause of death.
>Fitness and Diving Issue
>Symptomatic coronary artery disease is a contraindication to safe diving: don't dive with it. Coronary artery disease results in a decreased delivery of blood - and therefore, oxygen - to the muscular tissue of the heart. Exercise increases the heart's need for oxygen. Depriving myocardial tissue of oxygen can lead to abnormal heart rhythms and/or myocardial infarction, or heart attack.
>The classic symptom of coronary artery disease is chest pain, especially when it follows exertion. Unfortunately, many people have no symptoms before they experience a heart attack. Cardiovascular disease is a significant cause of death among divers. Older divers and those with significant risk factors for coronary artery disease should have regular medical evaluations and appropriate studies (e.g., treadmill stress test).
>Medication Used in Treatment
>Medications typically used in the treatment of this disease include nitroglycerin, calcium channel blockers and beta-blockers. At some point, someone with coronary artery disease may need a revascularization procedure, or the re-establishment of blood supply, through bypass surgery or angioplasty. If the procedure is successful, the individual may be able to return to diving after a period of healing and a thorough cardiovascular evaluation (see "Coronary Artery Bypass Grafting,").
>For more information on cardiovascular conditions, see the complete article by Dr. James L. Caruso on Cardiovascular Fitness and Diving from the July/August 1999 issue of Alert Diver.