Each year, heart disease causes 19 million deaths worldwide – nearly twice the number of deaths caused by cancer – yet public perceptions of heart disease and cancer are markedly different.
Most Americans between the ages of 40 and 75 undergo regular cancer screenings such as mammograms and colonoscopies, and if diagnosed with cancer, they are diligent in pursuing the recommended treatment. Many are aware of a family history of inherited cancer risks. Similar screening tests, effective medications, and genetic tests are available for heart disease, but few patients know about them, and fewer doctors offer them.
Michael V. McConnell, M.D., a preventive cardiologist and clinical professor of medicine at the Stanford University School of Medicine, has encountered this dismissive attitude toward heart disease in both his patients and his own family. In his new book, Fighting heart disease like cancerMcConnell explains the biological similarities between cancerous tumors and the plaque that grows inside blood vessels, a major cause of heart disease, and why we should take a similar approach to preventing and treating the two diseases.
It is similar to a tumor growing within the cardiovascular system and can become malignant and require serious treatment.
Michael McConnell
“We continue to think of heart disease as a simple problem of clogged pipes that need to be opened,” he writes in his book, “rather like a tumor growing in the heart’s blood vessels, potentially becoming malignant, and requiring serious treatment and frank discussion to stop it.”
We spoke to McConnell to speak candidly about this more aggressive approach to fighting heart disease.
How did you realise that heart disease needed to be fought in the same way as cancer?
It comes from both personal and professional experiences. The impetus for writing this book comes from something that unfortunately happened to my father-in-law. He was a scientist, an expert in early cancer detection. One day, he was feeling great, he was giving a talk, he was on his way to a celebratory dinner, but he ended up not making it. He had a heart attack, the blood flow to his heart was cut off, and his heart stopped. My daughters were only 10 and 13 years old at the time, and I don’t want this to happen to any other family.
Experts have known for some time that plaque (originally called atheroma, which means “fatty tumor” in Greek) can silently build up in the walls of the arteries of the heart. However, science now makes it very clear that these plaque “tumors” can become biologically active, dividing cells, attracting inflammatory cells, and growing within the artery walls for quite a long time without causing symptoms. Plaque can rupture and cause a blood clot. You can go from no blockage to a complete blockage in no time.
There are balloons, stents and bypass surgeries to treat severely blocked arteries, but waiting until the end of heart disease is often too late, and many people die before they even reach hospital.
The message I want to get across is that this is not just a plumbing disease, it’s a biological disease. Just like an oncologist looks for cancer, we need to look for early tumors and biological activity. If we can catch it early, we can do a lot to stop this and reverse it.
How does plaque develop in arteries?
Plaque usually develops when fat infiltrates the artery wall. The three main “growth factors” are high cholesterol, blood pressure, and blood sugar (if you have diabetes). The immune system then sends in macrophages, cells that devour and remove material. The macrophages ingest large amounts of fat, but instead of removing it, they die in the blood vessel wall. The dead cells continue to cause more inflammation. These factors make the plaque more “malignant” and more likely to rupture.
Then there’s the iceberg problem: plaque can grow very large on the inside of the artery wall, but only a small part of it protrudes into the area where blood is flowing.
Michael McConnell
Then there’s the iceberg problem: plaque can grow very large on the inside of an artery wall, but only a small amount protrudes into the area where blood is flowing, causing no symptoms. Angiograms, which show images of blood flow, only see the tip of the iceberg.
This silent plaque can suddenly crack, tear, or rupture, and then blood flowing over the plaque can form a blood clot to seal the problem in. One study found that the blood clots that cause heart attacks don’t usually occur in the places where the plaque was most noticeable.
You say no one should have a heart attack, but how do we prevent plaque growth?
We should not wait until the disease is terminal, because the first symptoms may be the last, as happened to my father-in-law, and we should be serious about early detection, when it is most treatable and reversible.
Non-invasive imaging techniques can see beyond the tip of the iceberg, right down to where plaque is growing inside the wall. The primary screening test is called a coronary artery calcium scan (CAC), which is an x-ray scan that can detect calcium deposits in plaque. It works in much the same way as a mammogram, which looks for calcifications in breast cancer tumors.
Preventive approaches include a heart-healthy lifestyle as well as lowering bad cholesterol (LDL) as much as possible with drugs such as statins or PCSK9 inhibitors. This is what we call preventive chemotherapy. This can inhibit or reverse the biological activity of plaque. There are also several drugs under investigation that directly address inflammation, some originally developed to treat cancer, that may also help make plaque more benign and less likely to cause a heart attack.
What do you want people to take away from this book?
Make sure you know your numbers: Talk to your doctor about your heart disease risk score, now known as PREVENT, which predicts your 10- and 30-year risk of heart attack, stroke and heart failure. Many men in their 50s and women in their 60s, and even younger if they have a family history, are at high enough risk that they should undergo preventive therapy or screening tests such as a CAC scan to see if they have plaque buildup.
There are many more people we can help.
Michael McConnell
Even though highly effective drugs are available, only half of U.S. patients who would benefit from cholesterol-lowering medications take them. In low- and middle-income countries around the world, that figure is just 8 percent. There are many more people we can help.
Should we be more concerned about heart disease than we are now?
People should definitely be aware of how serious heart disease is, I titled one of my chapters “Heart Disease is Like Cancer, But Worse,” because not only does it kill more people, it can kill you faster.
Although I strongly encourage preventive healthy behaviors in my patients, once plaque has built up in the arteries of the heart, a little more exercise or a few improvements in diet cannot stop the plaque from growing, rupturing, and causing death. There are drugs that are very effective at stopping or reversing the growth, but it needs to be treated like a growing tumor.
When you tell a patient that they have what is essentially the equivalent of a cancer growing in the arteries of their heart, it is often a very serious and visceral experience.
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