2Human Heart beats 100,000 time a day Moving 6 quarts of blood through 60, 000 milesOf vessels(that’s 20 times theDistance from coast toCoast)The heart itself holds only 10 ounces of blood, but pumps at such a force that that a severed artery can propel blood several feet into the air.
6Broken Hearts Coronary Heart Disease is the #1 killer in the USA 500, 000 people die from it each year in the USA7.2 million die worldwideMore than 400,000 heart bypasses are performed in the USA each year
8Misconceptions about Heart Disease Most think cholesterol silts into arteries, blocking them like a clogged pipe. Then the artery gets completely blocked causing a heart attack— no blood is getting through to the heart.When actually, Plaque is a pimple-like growth inside an artery wall with a “kind of chronic pus”
11"Heart disease is not a one- or two-gene problem," says cardiac researchers Steven Ellis. Like most researchers, he suspects that dozens of genes end up contributing to a predisposition:Some affect arterial integrity,others inflammation (which both causes and exacerbates arterial cracks),and still others the processing of lipids (the fats and cholesterol that turn into plaques).Of the several dozen genes, each may contribute just one percent to a person's total risk—an amount that may be compounded, or offset, by outside factors like diet. As one doctor told me, any person's heart attack risk is "50 percent genetic and 50 percent cheeseburger."
12Genes plus Other Risk Factors By tracking these genetic mutations, researchers hope to create a comprehensive blood test that could calculate a person's susceptibility to heart disease by adding up the number of risky variables:High unhealthy cholesterol levels (quadruples risk)Smoking (double or triple risk)Abdominal obesity (more than doubles risk)High blood pressure/Hypertension (nearly triples risk in men, doubled it for women)Stress & Depression (almost triples risk)Lack of exercise (increases risk by 20%)Diabetes (quadruples risk for women, doubles it for men)Healthy Diet (decreases risk by 30%)Assessing risk is crucial, Ellis says, because heart disease is often invisible.In fact, 50 percent of men and 64 percent of women who die of heart disease die suddenly, without experiencing any previous symptoms.
13Reducing Risk by Prevention Since detecting Heart Disease and predicting whether a heart attack is imminent is so difficult, prevention for everyone is advised.The only thing proven to reduce the risk of a heart attack in someone with plaque is the same thing that works to prevent plaque from developing in the first place —Lowering blood pressure and blood sugarnot smokingand Controlling cholesterol levels with Statins
14Statins: LipitorIs a Drug that reduces the amount of LDL (“bad” low-density lipoproteins) in the blood made by the LiverMade by Pfizer, it’s best selling drug ever made with $12 Billion in worldwide annual salesStatins in general are the most prescribed class of drugs in the world (11.6 million monthly prescriptions in US alone)
15Statins: How do they work? They work by blocking an enzyme in the liver that is involved in producing cholesterol within liver cells. "This tricks the liver cells into thinking the cholesterol levels are too low within the cell and the cell puts more receptors onto its surface, which drag the bad LDL cholesterol out of the blood," explains Dr. Rory Collins, professor of epidemiology at Oxford University. "The liver then breaks down that cholesterol and it's excreted into the bile and into the gut." Collins has conducted the biggest study of statins to date, covering 20,000 people over five years. The study suggested that a person who has had high cholesterol for decades could reduce their risk of heart attack or stroke by 25 per cent within just a few years of statin treatment. The study also suggested that the risk would continue to decrease, the longer the treatment continued.
16Why do we make “bad” LDL in the 1st place? At one time, millennia ago, it may have been important for the human body to be able to produce cholesterol – because early humans may have gone long periods between meals, which meant they couldn't count on getting enough cholesterol. But Dr. David Jenkins – a Canada Research Chair in nutrition, and a professor of medicine at the University of Toronto – says that's not the case for the modern couch potato. "We've got these ancient bodies with these ancient genes which are all destined to make sure that we've got enough cholesterol to fulfil essential functions," Jenkins told CBC Radio's Quirks and Quarks. "Today, unfortunately, we've taken out all those nice things in the diet that take cholesterol out of the body and have brought in a whole load of very nice refined foods that allow us to sit around, not do too much, and just synthesize cholesterol." Those refined foods help your body produce the bad kind of cholesterol.
17Angiogram of Healthy Heart The picture of health, an angiogram of a human heart shows blood vessels in sharp detail. To take an angiogram, or arteriogram x-ray, doctors must first inject the patient with a special opaque dye that allows a clear view of the heart's blood vessels, including the large left and right coronary arteries. Narrowed arteries indicate the presence of coronary artery disease. Blockages of either of the coronary arteries could lead to a heart attack. Such x-rays help doctors determine a course of treatment.
18Inside the HeartTissue-paper thin but tough, the valves of the human heart open and close to pump 6 quarts (0.9 liters) of blood a day through 60,000 miles (97,000 kilometers) of vessels. That's equivalent to 20 treks across the United States from coast to coast. The heart is a magnificent machine when it's in good working order. But coronary heart disease is the number one killer of American men as well as women, resulting in 500,000 deaths in the United States and killing 7.2 million people worldwide each year.
19Donor HeartAt Houston's Ben Taub Hospital, careful—and quick—steps are taken to prep a donor heart for transport and transplantation. To preserve the harvested heart, a member of the transplant team flushes it with a cooling solution that slows its metabolic rate. Doctors have a narrow window of only four to six hours to get the heart into the waiting recipient before it is no longer viable.
20Enlarged HeartMartti Tenhu, chief medical examiner in Helsinki, Finland, illustrates the differences between a normal human heart and one enlarged by alcoholism and high blood pressure. Covered in scar tissue, the enlarged organ is nearly twice the normal size. Such alcoholic cardiomyopathy weakens the heart so that it is unable to pump blood adequately.
21Chest X-RayCause for concern is apparent in the chest x-ray of an 82-year-old cardiac patient. Pneumonia in his right lung can be seen as clearly as the pacemaker implanted to regulate the rhythm of his heart. Pneumonia is a common hospital-acquired infection.
22Controlling Risk Factors nearly eliminates heart attacks altogether A 50-year-old man with:No diabetesDoesn’t smokeWith normal cholesterol and blood pressureHas only a 5% chance of having a heart attack or symptoms of heart disease, like chest pain, over the next 45 yearsSame goes for a 50-year-old woman with those risk factors under control. Her chance of symptomatic heart disease is 8 percent, slightly higher than the man’s because women live longer
23So Why does Heart Disease persist? Only 5 percent of 50-year-olds have those risk factors under control.Even with just one major risk factor, such as a high cholesterol level, and a man’s chance of having symptomatic heart disease rises to 50 percent.A woman’s chance rises to 39 percent.
24Prevention gets little attention The fact is people like to eat cheeseburgers, watch TV and go around in carsIt’s hard for a person to worry about a disease that hits 10 or 20 years down the road
29This polyurethane heart can keep critically ill cardiac patients alive while they await a donated human heart. Once the device is surgically implanted, its attached plastic tubes run through the patient's skin to a battery-powered pneumatic pump. Despite the cost—$106,000—the demand is strong. Some 3,000 people await heart transplants in the U.S., but only about 2,100 donor hearts are available each year. While boosting the supply of artificial hearts is a relatively simple technical hurdle, increasing the supply of human hearts is more challenging. Who will be tomorrow's donors? That question lingers for a patient in Germany, who recently received a CardioWest artificial heart like this one.
36Widow-MakerAn angiogram reveals an abrupt closure in a critical coronary artery.This technique uses a catheter, dye, and x-rays to navigate and study blood vessels. In a second angiogram, bottom, after a stent has been inserted, blood flow is restored.
37Figure 1 (a) Angiogram shows critical stenosis in the intracranial right internal carotid artery, intrapetrous segment (arrow). (b) Post-angioplasty angiogram shows 40% residual carotid stenosis (arrow). (c) Follow-up angiogram shows recurrent carotid 70% stenosis (arrow). (d) Post-stent angiogram shows excellent results with no significant residual carotid stenosis (arrow).