First of all, here are some of the basics about hypertension. Blood pressure (BP) is simply defined as the pressure the blood exerts on the walls of the blood vessels. Hypertension is elevated blood pressure (above 140/90). Blood pressure is normally expressed as a number over a number (___/___). The top number is the systolic blood pressure, a measurement taken while the heart is contracting. The diastolic blood pressure is the bottom number, taken while the heart is relaxing. A “normal” BP is less than 120/80. A BP that is 120-139/80-89 is considered pre-hypertension. Stage I hypertension is a BP ranging from 140-159/90-99 and Stage II is >160 / >100.
Why is this all so important?
Hypertension (HTN) can cause damage to many body organ systems. It can cause damage to the brain, kidneys, eyes, lungs, reproductive system and of course the cardiovascular system. For this discussion we will focus on the heart and blood vessels.
The heart is a pump, and its job is to pump the blood out of the heart into the blood vessels. The heart has to overcome the force (BP) in the blood vessels to pump effectively. The higher the BP is, the greater the workload on the heart, and this can lead to damage over time. The harder the heart muscle has to work, the bigger it gets and that can eventually lead to a condition called left ventricular hypertrophy. HTN can cause heart attacks and cause heart failure as the heart muscle gives out.
Hypertension damages the blood vessels by causing microscopic tears and scars in the vessel walls. The damaged blood vessels collect more fat and cholesterol, which leads to plaque formation. Over time the plaque causes the vessels to narrow and harden, a term called atherosclerosis. Blood clots can form in these narrowed vessels and block the blood flow to the heart or other tissues. When blood vessels are blocked and blood is not reaching the tissues, damage can occur causing heart attack, stroke and damage to the organs.
A person may not necessarily know that they have high BP — all too often we find out when it is too late and damage has been done. This is why sometimes HTN is referred to as the “silent killer.” Here are some scary statistics… For every 20/10 increase in blood pressure (over 115/75), it is estimated that the risk of heart disease doubles! According to the American Heart Association, 77% of Americans treated for a first stroke have BP over 140/90; 69% of Americans who have a first heart attack have BP over 140/90; 74% of Americans with congestive heart failure have blood pressure over 140/90.
What is the moral of the story? Know your BP numbers – have it checked often and keep track of it. When you are at a normal BP, do your best to maintain it! If you are in the pre-hypertension stage, work hard to get that BP down by diet and exercise. If you are a person with HTN, take your medications as directed, make lifestyle changes and keep in regular contact with your health care provider to stay as healthy as you can!
answer submitted by: Melissa Leguillon, APN CNP, Nurse Practitioner, Cardiovascular Services