0:00:07.410,0:00:12.980 Approximately 7 million people around the [br]world die from heart attacks every year, 0:00:12.980,0:00:14.901 and cardiovascular disease, 0:00:14.901,0:00:18.060 which causes heart attacks and other[br]problems like strokes, 0:00:18.060,0:00:20.500 is the world's leading killer. 0:00:20.500,0:00:22.650 So what causes a heart attack? 0:00:22.650,0:00:25.140 Like all muscles, the heart needs oxygen, 0:00:25.140,0:00:28.550 and during a heart attack,[br]it can't get enough. 0:00:28.550,0:00:30.541 Fatty deposits, or plaques, 0:00:30.541,0:00:33.241 develop on the walls [br]of our coronary arteries. 0:00:33.241,0:00:37.208 Those are the vessels that supply[br]oxygenated blood to the heart. 0:00:37.208,0:00:39.490 These plaques grow as we age, 0:00:39.490,0:00:40.760 sometimes getting chunky, 0:00:40.760,0:00:41.780 hardened, 0:00:41.780,0:00:43.091 or enflamed. 0:00:43.091,0:00:45.960 Eventually, the plaques can turn[br]into blockages. 0:00:45.960,0:00:48.791 If one of the plaques ruptures or cracks, 0:00:48.791,0:00:52.169 a blood clot will form around it[br]in minutes, 0:00:52.169,0:00:56.252 and a partially closed artery[br]can become completely blocked. 0:00:56.252,0:00:58.712 Blood flow is cut off [br]to the cardiac muscle 0:00:58.712,0:01:03.061 and the oxygen-starved cells start to die[br]within several minutes. 0:01:03.061,0:01:05.911 This is a myocardial infarction, 0:01:05.911,0:01:07.311 or heart attack. 0:01:07.311,0:01:11.302 Things can rapidly deteriorate[br]in the absence of treatment. 0:01:11.302,0:01:14.712 The injured muscle may not be able[br]to pump blood as well, 0:01:14.712,0:01:17.102 and its rhythm might be thrown off. 0:01:17.102,0:01:21.472 In the worst case scenario,[br]a heart attack can cause sudden death. 0:01:21.472,0:01:24.441 And how do you know that someone[br]is having a heart attack? 0:01:24.441,0:01:26.723 The most common symptom is chest pain 0:01:26.723,0:01:29.622 caused by the oxygen-deprived [br]heart muscle. 0:01:29.622,0:01:32.822 Patients describe it as crushing[br]or vice-like. 0:01:32.822,0:01:34.633 It can radiate to the left arm, 0:01:34.633,0:01:35.472 jaw, 0:01:35.472,0:01:36.241 back, 0:01:36.241,0:01:37.473 or abdomen. 0:01:37.473,0:01:41.622 But it's not always as sudden and dramatic[br]as it is in the movies. 0:01:41.622,0:01:43.513 Some people experience nausea 0:01:43.513,0:01:44.932 or shortness of breath. 0:01:44.932,0:01:48.283 Symptoms may be less prominent[br]in women and the elderly. 0:01:48.283,0:01:52.592 For them, weakness and tiredness[br]may be the main signal. 0:01:52.592,0:01:54.513 And surprisingly, in many people, 0:01:54.513,0:01:58.642 especially those with diabetes,[br]which affects the nerves that carry pain, 0:01:58.642,0:02:01.192 a heart attack may be silent. 0:02:01.192,0:02:03.993 If you think that someone might be [br]having a heart attack, 0:02:03.993,0:02:07.163 the most important thing [br]is to respond quickly. 0:02:07.163,0:02:11.032 If you have access to emergency medical[br]services, call them. 0:02:11.032,0:02:13.474 They're the fastest way [br]to get to a hospital. 0:02:13.474,0:02:15.825 Taking aspirin, which thins the blood, 0:02:15.825,0:02:18.624 and nitroglycerin, [br]which opens up the artery, 0:02:18.624,0:02:21.594 can help keep the heart attack[br]from getting worse. 0:02:21.594,0:02:24.933 In the emergency room, [br]doctors can diagnose a heart attack. 0:02:24.933,0:02:27.524 They commonly use an electrocardiogram 0:02:27.524,0:02:30.034 to measure the heart's [br]electrical activity 0:02:30.034,0:02:33.294 and a blood test to assess [br]heart muscle damage. 0:02:33.294,0:02:36.765 The patient is then taken to a high-tech[br]cardiac suite 0:02:36.765,0:02:40.105 where tests are done [br]to locate the blockages. 0:02:40.105,0:02:42.734 Cardiologists can reopen [br]the blocked artery 0:02:42.734,0:02:47.365 by inflating it with a balloon[br]in a procedure called an angioplasty. 0:02:47.365,0:02:50.794 Frequently, they also insert a metal[br]or polymer stent 0:02:50.794,0:02:53.148 that will hold the artery open. 0:02:53.148,0:02:57.625 More extensive blockages might require[br]coronary artery bypass surgery. 0:02:57.625,0:03:01.730 Using a piece of vein or artery[br]from another part of the body, 0:03:01.730,0:03:05.866 heart surgeons can reroute blood flow[br]around the blockage. 0:03:05.866,0:03:09.389 These procedures reestablish circulation[br]to the cardiac muscle, 0:03:09.389,0:03:11.367 restoring heart function. 0:03:11.367,0:03:13.111 Heart attack treatment is advancing, 0:03:13.111,0:03:15.448 but prevention is vital. 0:03:15.448,0:03:19.070 Genetics and lifestyle factors[br]both affect your risk. 0:03:19.070,0:03:22.174 And the good news is that you can[br]change your lifestyle. 0:03:22.174,0:03:24.566 Exercise, a healthy diet,[br]and weight loss 0:03:24.566,0:03:27.039 all lower the risk of heart attacks, 0:03:27.039,0:03:29.019 whether you've had one before or not. 0:03:29.019,0:03:32.006 Doctors recommend exercising[br]a few times a week, 0:03:32.006,0:03:35.180 doing both aerobic activity[br]and strength training. 0:03:35.180,0:03:38.826 A heart-healthy diet is low[br]in sugar and saturated fats, 0:03:38.826,0:03:41.096 which are both linked to heart disease. 0:03:41.096,0:03:42.567 So what should you eat? 0:03:42.567,0:03:44.237 Lots of fiber from vegetables, 0:03:44.237,0:03:46.683 chicken and fish instead of red meat, 0:03:46.683,0:03:49.946 whole grains and nuts like walnuts[br]and almonds 0:03:49.946,0:03:52.356 all seem to be beneficial. 0:03:52.356,0:03:56.737 A good diet and exercise plan can also[br]keep your weight in a healthy range, 0:03:56.737,0:03:59.548 which will lower [br]your heart attack risk as well. 0:03:59.548,0:04:03.167 And of course, medications can also[br]help prevent heart attacks. 0:04:03.167,0:04:06.267 Doctors often prescribe low-dose[br]aspirin, for example, 0:04:06.267,0:04:09.976 particularly for patients who've[br]already had a heart attack 0:04:09.976,0:04:12.847 and for those known to be[br]at high risk. 0:04:12.847,0:04:14.956 And drugs that help manage risk factors, 0:04:14.956,0:04:18.337 like high blood pressure, cholesterol,[br]and diabetes, 0:04:18.337,0:04:21.038 will make heart attacks less likely, too. 0:04:21.038,0:04:25.057 Heart attacks may be common, [br]but they don't have to be inevitable. 0:04:25.057,0:04:26.176 A healthy diet, 0:04:26.176,0:04:27.599 avoiding tobacco use, 0:04:27.599,0:04:28.728 staying fit, 0:04:28.728,0:04:31.528 and enjoying plenty of sleep[br]and lots of laughter 0:04:31.528,0:04:35.769 all go a long way in making sure[br]your body's most important muscle 0:04:35.769,0:04:37.417 keeps on beating.