Today we’re going to talk about the heart...
Maybe you’re thinking to yourself, “wow, that’s a big topic!” If so, you’re right. In the last half century, scientists have made huge advances in their understanding of the heart. They know an incredible amount about how it works, how to keep it healthy, and how to heal it when it’s sick. And, they are learning more all the time. Even so, heart disease is still a big problem in Canada. Heart disease affects both men and women. While more men died of coronary artery disease and heart attacks in 2000, more women died of congestive heart failure during the same period.[1] The good news is that death rates from heart disease and stroke actually decreased between 1969 and 1999. We all need to take heart disease very seriously. Yet, not all Canadians are taking steps to reduce their risk of cardiac disorders. Over 5 million people over age 15 still smoke.[2] A whopping 48 percent of adults are overweight or obese,[3] and 23 percent of adults have been diagnosed with high blood pressure (about 5 million Canadians).[4] T hese are all controllable risk factors, as we’ll see a little later on. For now, these risk factor statistics tell us there is still plenty of room for improvement. Today’s presentation will help you identify your risk factors and show you what you can do to control them. It will also give you an overview of heart diseases and how doctors diagnose and treat them. We’ll start by reviewing how the heart works, so that you understand what can go wrong with it, and why. Then we’ll discuss the warning signals of a heart attack and what to do if you think you’re having one. Next, we’ll spend some time discussing common conditions and risk factors for heart disease. We’ll look at common tests to diagnose heart disorders and at modern medicine for the broken heart. Finally, we’ll profile some of the work the Heart and Stroke Foundation is doing. We’ll be covering a lot of ground in a short time. Don’t worry — you don’t need to remember everything you’ll hear in the next few minutes. The goal is to give you a very broad overview of heart issues and information, help you recognize the warning signals of a heart attack, and give you practical tips on how to improve your own heart health. Alright then — let’s talk about the heart. As you know, the heart is a muscle. It’s about the size of a clenched fist, and it’s located more or less in the centre of the chest, just slightly to the left side and behind the breast bone. Its job is to pump blood around the body — and it does this with incredible efficiency. The average heart pumps about 100,000 times a day, or two and half billion times during a 70-year lifetime. Each day it pumps about 7,600 litres of blood through the 96,000 kilometres of blood vessels in the human body. [5] That’s a whole lot of pumping action! The heart has four hollow chambers, two on top and two on the bottom. The top chambers are called atria, and the bottom ones are called ventricles. These chambers are separated by valves. Here’s how it works: the left atrium receives freshly oxygenated blood from the lungs, and pumps it into the left ventricle, immediately below. The left ventricle, which is the most powerful chamber of the heart, pumps this fresh blood throughout the body. This blood supplies your cells with the oxygen and nutrients they need to function. As blood circulates thought the body, it delivers oxygen and nutrients to cells on its route. By the time it returns from its trip though the body to the right atrium of the heart, it has dropped off most of its life-giving cargo — and is ready to pick up a fresh supply. Oxygen-depleted blood flows into the right atrium of the heart and is pumped into the right ventricle. From there, it travels to the lungs, where it picks up a fresh load of oxygen. Then, it is pumped back into the left atrium — and the cycle begins again. The pumping action is controlled by a complex electrical system, which ensures the heart speeds up when your body needs more blood, and slows down when you’re at rest. To do all this pumping, the heart muscle itself needs blood — lots of it. This blood is supplied by the coronary circulation —the blood vessels, both veins and arteries, which surround the heart. There are two main coronary arteries, each about as thick as a drinking straw. These coronary arteries branch out into smaller blood vessels which supply every part of the heart muscle with blood. The coronary arteries play a very important role in heart health. As we age, these vital arteries often become clogged by atherosclerosis — narrowing of the arteries due to the slow build-up of a fatty substance called plaque on the artery walls. This is known as coronary artery disease, and we’ll talk about it in a little while. If a coronary artery is suddenly blocked, for example by a blood clot, the result is a heart attack. Heart attacks occur when blood flow through one or more coronary arteries is blocked. When this happens, the vital blood supply to part of the heart muscle is cut off. If blood flow isn’t restored within a minute or two, the heart muscle starts to die. There are about 70,000 heart attacks each year in Canada.[6] Heart attack victims can often survive and make full recoveries— if they reach hospital soon enough and receive treatment. Heart attacks warning signals are all too often ignored — and the results are tragic. Let’s take a moment right now to review them, and what to do if you experience them. The classic warning signal of a heart attack is crushing squeezing pain in the chest, often accompanied by pain in the left arm. However, many people experience heart attacks differently. A heart attack can cause pain in the chest, neck, jaw, shoulder, arms or back. The pain can be a burning or squeezing sensation. Some people experience heart attack pain as heaviness, tightness or pressure. Other people, especially women, may experience only vague chest discomfort. Or, the pain may feel like heart burn. Other signs of a heart attack may include shortness of breath or difficulty breathing, nausea, indigestion or vomiting , sweating or cool, clammy skin. Heart attacks also produce emotional symptoms. Fear and denial often go with a heart attack. Many people tell themselves they can’t really be having a heart attack, when they actually are! Denial is an especially deadly symptom because it delays the proper response — that is, seeking treatment right away. Heart attack warning signals can be mild or severe. They can occur in any combination. If you —or someone you know — is having ANY of these symptoms, call 9-1-1 or your local emergency number immediately. If you have been prescribed nitroglycerine by your doctor, take as directed. Because it’s so important, I’ll say it once again. If you even suspect you are having a heart attack – stop all activity and get help right away. Don’t wait until it’s too late. I can’t emphasize this point enough. If you go the hospital and you find you’re not really having a heart attack, that’s good news. Don’t waste a single second feeling embarrassed, or wondering if you did the right thing. You did! And if you really ARE having a heart attack, your quick action may well save your life. Or, it may make the difference between full recovery and long-term disability. While we’re on the topic of heart attacks, it’s worth mentioning Cardiopulmonary Resuscitation, or CPR for short. CPR is a life-saving skill that enables trained individuals to save the lives of heart attack victims, as well as people with other life threatening conditions. Anyone can learn CPR — and the more people who do learn it, the greater the chances of victims surviving heart attacks. That’s because CPR is the most important factor in reducing pre-hospital deaths from heart attacks. A CPR course shows you how to recognize heart attack symptoms and what action to take if someone has one. The course also teaches lifesaving skills such as opening a victim’s airway, artificial respiration and external circulation of blood. The Heart and Stroke Foundation of Canada sets the guidelines for CPR training in Canada. These guidelines are developed based on the latest scientific research and updated as new information becomes available. In the last few years, technology has given emergency responders an amazing new tool to help people at risk of sudden cardiac death. It is called an automated external defibrillator, or AED for short. For up-to-date, reliable information on heart disease and stroke, visit the Heart and Stroke Foundation Web site. DISCLAIMER: THIS IS NOT INTENDED IN ANY WAY AS MEDICAL ADVICE. IF YOU BELIEVE YOU HAVE A HEALTH PROBLEM, PLEASE CONSULT A PHYSICIAN IMMEDIATELY.