Coronary Artery Disease or CAD is a common condition amongst the human population. As people age, they tend to acquire health problems and CAD is one of the most prevalent. In fact, there are more than 2.5 million Americans with this condition. Unfortunately, divers are not immune to acquiring CAD and when divers have it they might wonder if they can still dive. There is no black and white answer to this question so let's take a look at what it takes to be able to dive with CAD.
First let's take a look at what CAD is. CAD is a condition that begins with a hardening of the arteries, known as atherosclerosis. This is the condition when the arteries become narrowed and eventually blocked by something that is called plaque. Eventually the arteries become blocked and blood cannot flow through them. Once this happens the heart muscle slowly dies to the point where the person has a heart attack.
So what about diving with CAD? Well, in a nutshell, no one should dive with CAD if the condition has remained untreated. Diving with CAD increases the risk of arrhythmia, which is an irregular heartbeat, and can cause unconsciousness and even sudden death when diving. No one should dive unless they have consulted with their physician and knows for certain that their heart can take the stress of the exercise that is required when diving.
It is easy enough for doctors to determine whether or not your heart can take the stress of exercise. A simple stress test on the heart will tell it all. Doctors can measure the blood flow distribution of the heart by adding a certain isotope to the blood via intravenous injection. Then you exercise on a treadmill or stationary bike and a scan is taken of the heart after the exercise session to see whether there are any losses in blood flow and where those losses occur. The doctor can reproduce the type of workload that your heart will undergo when diving and thus will be able to tell if your heart can handle the stress.
Of course, prevention of CAD is your best bet. It is wise to know the risk factors, which include having high cholesterol, smoking, having high blood pressure, obesity, diabetes, and being over age 45 for men and age 55 for women. If your family has a history of CAD you may also be at risk and if you meet the age criteria or meet any two of the other criteria, then you should get a complete physical evaluation done before you dive.
All of these risk factors are manageable, which is a big plus for anyone, a diver or not. The first thing to know is that the cessation of smoking is a huge reduction in risk when it comes to getting CAD. As hard as this is to do, it is worthwhile. You should also get your blood checked annually to test the levels of triglycerides and cholesterol, including both HDL (good cholesterol) and LDL (bad cholesterol). Total cholesterol should be below 200, LDL should be below 130, and triglycerides should be below 120. If any of these are high, then you can immediately start on a program to get these levels back into normal range through a change in diet, exercise, a reduction in weight, and lower alcohol consumption. You should also monitor your blood pressure and keep it down. Maintaining a normal blood pressure can be accomplished by a lowered alcohol intake, less salt in the diet, less stress, and exercise. There are drugs to help with all these conditions if needed.
Once you have these risk factors under control, then you should be able to dive if your doctor gives you the okay to do so. If you have CAD, then diving should be avoided in most cases unless you have had corrective surgery, such as a bypass or balloon angioplasty. After you have had these procedures and have completely healed, the exercise test can be performed to see if your heart can handle the stress of exercise.
Please remember how important it is to find out if you have CAD and to manage it effectively before you dive. The most common cause of sudden death during a dive in a diver over 40 is a blocked artery and fatal ventricular fibrillation, which is a rapid fluttering of the heart. You are also frequently diving in remote locations far away from advanced medical care. If something happened because you had CAD, the chances of survival would be slim. Knowing this is the case, do you really want to take any chances with your own safety while diving? Be smart and be safe. Be sure to be checked for CAD before you dive and if you have it, treat it first.