Mending Broken Hearts - IELTS Reading Answers & Explanations

You should spend about 20 minutes on Questions 27-40 which are based on READING PASSAGE 3 on the following pages.

Mending Broken Hearts

A Although hearts suffer many maladies-valves leak, membranes become inflamed – coronary heart disease, which can lead to heart attack and ultimately to heart failure, is the number one killer of both men and women in the United States, where 500,000 the annually. Worldwide, it kills 7.2 million people every year. Exacerbated by the export of Western lifestyle – motorized transport, abundant meat and cheese, workdays conducted from the comfort of a well-padded chair – incidence of the disease is soaring.

B To help stem this lethal tide, cardiologists can prescribe such cholesterol-lowering drugs as statins to help keep arteries clear. They can advise patients to change their habits, or they can operate to fix an immediate problem. Angioplasty is one procedure, and surgery to bypass the diseased arteries is another – each year more than 400,000 bypasses are performed in the U.S. Transplants can replace severely damaged hearts, and artificial ones can keep people alive while they wait for a donor heart. But in the face of an impending global epidemic, none of these stopgap measures addresses the essential question: Who gets heart attacks and why?

C The human heart beats 100,000 times a day, propelling six quarts (5.6 liters) of blood through 60,000 miles (96,560.6 kilometers) of vessels – 20 times the distance across the U.S. from coast to coast. The blood flows briskly, surging out of a ten-ounce (283.5 gram) heart so forcefully that large arteries, when severed, can send a jet of blood several feet into the air. Normally the relentless current helps keep blood vessels clean. But where an artery bends, tiny eddies form, as in a bend in a river. This is where bits of sticky, waxy cholesterol and fat can seep into the artery wall and oxidize, like butter going rancid. Other matter piles up too. Eventually, the whole mass calcifies into a land of arterial stucco, or plaque.

D Until recently, cardiologists approached heart disease as a plumbing problem. Just as mineral deposits restrict the flow of water through a pipe, an accretion of plaque impedes the flow of blood through an arterial channel. The more crud in the system, the greater likelihood that a dammed artery will trigger a heart attack. Doctors now dismiss this "clogged-pipes model" as an idea whose time has passed. It's just not that simple.

E Most heart attacks are caused by plaque embedded within the artery wall that ruptures, cracking the wall and triggering the formation of a blood clot. The clot blocks the flow of blood to the heart muscle, which can form the lack of oxygen and nutrients. Suddenly, the pump stops pumping.

F Contrary to the clogged pipes model, heart attacks generally occur in arteries that have minimal or moderate blockage, and their occurrence depends more on the kind of plaque than on the quantity. Scientists have been struggling to figure out what type is most responsible. Paradoxically, findings suggest that immature, softer plaques rich in cholesterol are more unstable and likely to rupture than the hard, calcified, dense plaques that extensively narrow the artery channel. But understanding the root cause of the disease will require much more research. For one thing, human hearts, unlike plumbing fixtures, are not stamped from a mold. Like the rest of our body parts, they are products of our genes.

G Don Steffenson was putting duck-hunting decoys out on a small lake one fall afternoon in South Western Iowa when his heart attack hit. The infarction was massive and unexpected. It's likely that Steffensen survived only because a buddy was carrying nitroglycerin tablets and quickly slipped one under his friend's tongue. Nitroglycerin is used to make dynamite; in the body, a heavily diluted form releases nitric oxide, which signals the smooth muscle cells in veins and arteries to relax, dilating the vessels.

H The Steffensen clan is enormous: more than 200 relatives spread over three generations, many of the youngest are now dispersed from Iowa to New York and beyond. Although heart trouble is common in the family, it had never struck anyone as unusual. "I attributed it to diet," shrugs Tina, a slim 38-year-old and the family's only vegetarian.

I It was a reasonable conclusion. The Steffensens were raised on the kind of farm food that the state is famous for – ham balls, meatloaf, pie, macaroni and cheese – and still popular even as careers have moved indoors. Driving north through cornfields to meet some of the family in Buffalo Center, I dined at a restaurant offering deep-fried sandwiches. A single ham and cheese hoagie – clunked in hot fat and served sizzling – seemed capable of stopping a heart all on its own.