"White Coat Syndrome" refers to a higher than usual blood pressure measurement when one visits his or her doctor. Just thinking about coming to see me strikes terror into the hearts of some and yet others begin to twitch in their seats. This makes diagnosing true hypertension that much more difficult. February is Heart and Stroke Prevention Month. These two entities account for almost a third of the deaths in Canada.
I often compare the body's circulation to my cottage plumbing system. There is a baseline pressure that exists all the time. Medically, this is called the diastolic reading. When the pump kicks in, the pressure rises to a peak level after which it begins to fall. This peak is the systolic value. Water flows in the cottage as long as the pressure stays between these two values. Each time the heart contracts, it too raises blood pressure to a peak systolic value. Blood vessels are elastic structures with the ability to somewhat regulate pressure. With time, they stiffen up with plaque deposits and it takes more pressure to drive the blood through them. When your cottage plumbing is plugged with silt or corrosion, one option is to try and increase the pump pressure. As I found out, this risks a valve bursting or a fitting becoming loose and results in everything getting wet. When the heart pump needs to increase pressure, it enlarges but with time it becomes boggier and less efficient. A thin vessel area can weaken, dilate and burst causing a hemorragic stroke. In another scenario, a piece of plaque can break off and be carried with the blood flow lodging in a small vessel of the brain or heart cutting out flow and oxygen. This is called an ischemic stroke or ischemic heart infarction.
The diagnosis of hypertension is much more than reading the numbers off the monitor. It takes months of monitoring and evaluation, and must meet certain criteria. Hypertension or high blood pressure is one of the most treatable risk factors for stroke and heart disease. Most people with hypertension have no symptoms and feel fine. Convincing someone to use medication for a condition without symptoms is indeed difficult. It is a relative intervention without certainty. The only thing that I can tell them for sure is that controlling hypertension reduces the chances but does not prevent strokes and heart attacks. The diagnosis starts with measuring your blood pressure using a mercury manometer and a properly fitted arm cuff. There is usually a small difference between the left and the right side. Ideal systolic-diastolic pressure values are under 120-80. Values over 180-110 are worrisome. A systolic-diastolic pressure greater than 140-90 is only suspicious. If you are healthy, I generally follow these persons for a number of months before any diagnosis is made. A complete physical examination is booked to look for hidden signs that the pump system is overworking. Your lifestyle and risk factors are assessed. We look for heart enlargement, bruits which are swishing sounds in partially clogged vessels, directly visualize the blood vessels in the back of the eyes, check for elevated sugar or cholesterol values, and evaluate your kidneys. An electrocardiogram is also performed. You may require further testing, which involves wearing a small automatic measuring device and recorder for 24 hours. All this information is amalgamated to decide on a diagnosis. This is why you might have the same blood pressure as your neighbor yet not considered to be hypertensive while he does.
I urge you to visit Heart and Stroke Foundation of Canada and take the risk assessment quiz. See your doctor and have your pressure measured if it has been a while. It is a simple non-painful step that might buy you a few extra laps around the frozen pond!
● Your Guide to Lowering High Blood Pressure from U.S. Department of Health and Human Services, National Institutes of Health
● Understanding Hypertension from Understanding-Hypertension.com.
● High Blood Pressure - News and Links from MEDLINEplus
● Many Women Ignore Greatest Health Risk: Heart Disease - Health News from Medical College of Wisconsin.