Atherosclerosis

Atherosclerosis is a slow change in the walls of the arteries, inside which firm plaques build up out of cholesterol, immune cells and connective tissue. The channel narrows, less blood reaches the organ, and the plaque itself can tear and shut the flow off completely. The process starts long before the first complaints, sometimes as early as young adulthood, and runs silently for years. How fast it moves, though, depends mostly on what a person does every day.

What happens inside the artery wall

It all begins with damage to the inner lining of the vessel. High blood pressure, tobacco smoke, high blood sugar and long-standing inflammation wear it down. Low-density cholesterol particles work their way into the damaged spot, immune cells gather around them, and that is how a plaque appears: soft at first, with a fatty core, and later hard, with calcium in it.

From there two things can happen. The plaque grows slowly and narrows the channel bit by bit, so the organ runs short of oxygen under exertion and the person feels it as pain or breathlessness that eases with rest. Or the thin cap of the plaque tears, a clot forms over the tear within minutes and the artery closes: that is how heart attacks and most strokes happen. Hence a conclusion that is not obvious at all: what is dangerous is not so much the thickness of the plaque as how fragile it is. A small soft plaque ruptures more often than a hard narrowing that has stayed the same for years.

Where the disease makes itself known

Arteries are affected all over the body, and the complaints depend on which stretch has narrowed most.

• Heart. Pressure, burning or heaviness behind the breastbone when climbing stairs, in the cold or after a meal; it lets go after a few minutes of rest. Sometimes there is no pain at all, only breathlessness or unaccustomed weakness.
• Legs. Pain in the calf or thigh muscles that comes on after roughly the same walking distance every time and forces a stop. Later come cold feet, hair loss on the shins and small wounds that will not heal.
• Neck and brain. Brief weakness in an arm, a drooping face, muddled speech, loss of vision in one eye, all of it clearing on its own within minutes. Such an episode is not a lucky escape but a warning of a stroke in preparation.
• Abdomen. A dull pain half an hour after eating, because of which the person starts to fear meals and loses weight.
• Kidneys. Blood pressure that stops responding to the usual medicines.

In a good share of people there are no complaints at all until the first acute event. That is why atherosclerosis is looked for not by symptoms but by risk factors.

What speeds the process up

• smoking, and any way of inhaling tobacco or nicotine, is the quickest way to ruin the lining of the vessels;
• high low-density cholesterol together with a low protective fraction;
• raised blood pressure, including the kind that cannot be felt at all;
• diabetes and prediabetes: excess sugar damages the vessels directly;
• extra weight, especially around the waist, and a sedentary life;
• chronic kidney disease and long-running inflammation: rheumatoid arthritis, psoriasis, an untreated infection;
• age, male sex and early vascular events in close relatives: these cannot be changed, but with them the bar for everything else is lower.

One rare but important cause deserves separate mention: familial hypercholesterolaemia. It is an inherited fault that keeps cholesterol high from birth and ages the arteries two or three decades ahead of time, so a heart attack is possible at thirty-five to forty-five in someone with no bad habits at all. What should raise suspicion is very high cholesterol that barely shifts with diet; heart attacks or sudden death in relatives before fifty-five in men and before sixty in women; firm yellowish nodules on the tendons, thickened patches on the eyelids and a pale ring at the edge of the iris in a young person. Diet is not the problem here, and the whole family should be checked, children included.

Signs that call for an ambulance

• pressing or burning chest pain lasting more than 15 minutes, spreading to the arm, neck, jaw or back, with cold sweat, nausea and a sense of dread;
• a drooping face, weakness of an arm or a leg on one side, slurred speech, sudden loss of vision or of balance, even if it has already passed;
• sudden severe pain in a leg or an arm, with pale or mottled skin, the limb cold, numb and hard to move;
• abrupt abdominal pain far worse than the examination would suggest, particularly with an irregular pulse;
• sudden severe breathlessness at rest.

Call the emergency service, 112 or your local number. Do not drive yourself and do not wait for it to pass: with a closed artery the count is in minutes.

What the tests show

The first step is simple and cheap: blood pressure in both arms, a lipid profile, glucose and glycated haemoglobin, kidney function and an electrocardiogram. To that the doctor adds weight, years of smoking and family history; together they give the risk for the years ahead, and that risk decides how forcefully to treat.

After that it depends. Ultrasound of the neck and leg arteries shows the plaques and the speed of the flow, while comparing the pressure at the arm and at the ankle tells whether the leg arteries are open. For chest pain there is an exercise test, an echocardiogram and, if needed, a scan of the coronary arteries or an angiogram. Calcium in the wall is visible on a scan and sharpens the outlook when the risk sits on the borderline.

What treatment can achieve

Plaques cannot be cleared away completely, and it would be dishonest to promise otherwise. But treatment halts the growth of a plaque and makes its cap sturdier, which means it lowers the chance of rupture and of a clot.

The backbone of drug treatment is the statins; if the effect falls short, the doctor adds medicines from other lipid-lowering classes. Blood pressure drugs, antiplatelet drugs and medicines for blood sugar in diabetes are used as well. Doses and combinations are chosen by the doctor according to the level of risk and to tolerance, which is why somebody else's regimen will not do.

A great many fears circulate about statins. Muscle aches do happen, but more often the cause lies elsewhere, and it can only be sorted out with a doctor, by changing the drug or the dose. Stopping them on your own is the worst option of all: the risk returns to where it started within weeks.

When the channel is critically closed, a procedure is discussed: a stent, a bypass or, for a dangerous plaque in the neck, its removal. For leg pain there is also a method without drugs: walking regularly until the pain appears, with short stops. Over time bypass vessels grow and the distance increases.

Habits that change the outlook

• give up smoking altogether: this starts working within the first months;
• walk, swim or cycle about 150 minutes a week, regularly rather than in bursts;
• less saturated fat and factory baking, more vegetables, pulses, nuts, fish and olive oil;
• alcohol does not protect the vessels: the less of it, the better;
• measure blood pressure at home and write the numbers down instead of going by how you feel;
• sleep enough, and have your breathing in sleep checked if there is loud snoring with pauses;
• take the prescribed medicines without breaks, including when you feel perfectly well.

Online consultation

At an online appointment the doctor goes through your complaints and your family history, judges the risk from the test results you already have, explains which investigations are needed and in what order, helps you make sense of the medicines you have been prescribed and their side effects, and says when a face-to-face visit to a cardiologist or a vascular surgeon is required.

This material is for information only and does not replace medical advice.