Emerson cardiologists discuss advances in cardiovascular medicine


7/20/2017

Heart disease is the most common cause of death in the U.S. However, thanks to an increasing emphasis on controlling cardiac risk factors, prevention efforts and effective treatment options, the incidence of coronary artery disease and heart attacks has decreased. Four Emerson cardiologists recently gathered to discuss progress in the last decade: Anjum Butte, MD; Stephen Dyda, DO, chief of the cardiovascular service at Emerson; Jonathan Greene, MD; and Kay Lee Kim, MD.

What tests determine someone’s cardiac risk level?

Dr. Dyda: The single best tool we have for estimating risk in people who don’t have obvious cardiovascular disease is a respected ten-year risk score, where you plug in gender, age, whether or not they smoke, and cholesterol and blood pressure measures, and it produces a number. It is a bit more sophisticated than, for example, telling someone they are at “moderate risk.” Day to day, that is what I rely on most. If I am considering prescribing a cholesterol drug, I order a blood test that checks for inflammation and a coronary calcium score, which determines the buildup of calcium in the walls of the coronary arteries.

Dr. Greene: We need to be aware of cardiac risk in young adults. This is clear from several recent studies that included young adults and looked at their coronary calcium scores. In these studies, people as young as 27 were found to have plaque in their arteries. Unfortunately, I have several patients in their early 30s who I’ve put on cholesterol medication for this reason because, long- term, we are concerned they could be headed for trouble.

What do we know about the relationship between stress and heart disease?

Dr. Greene: For chronic stress, the guidelines have changed to encourage stress reduction and lifestyle modification, in addition to exercise and diet modification. This is because various trials on yoga, relaxation and mindfulness showed impressive reductions in blood pressure and heart rate and decreases in cardiovascular outcomes, such as coronary artery disease. Now I tell my patients that the third leg of the cardiology stool, in addition to exercise and diet, is stress reduction.

Dr. Butte: The stress mechanism is different in women, possibly because they have smaller blood vessels. We also know their microvascular system reacts differently than that of men. There are gender differences in the outcome of acute stress. For example, the condition known as takotsubo cardiomyopathy, or broken-heart syndrome, can cause a heart attack. This is far more common in women.

Is there anything else we know about women and heart disease?

Dr. Kim: One important point is that women, as a result of the difference in their microvascular system, tend to have more coronary disease where the artery is not blocked; this is different from what we see in men. That can be challenging, although treatment that combines medication and exercise, such as cardiac rehab, can be effective.

Dr. Butte: The latest data indicates that, while they often have atypical symptoms, the most common symptom of heart attack in women is chest pain. We know that women develop heart disease, on average, about ten years later than men, but they are vulnerable to the same risk factors, especially smoking.

Dr. Greene: My major intervention with my female patients is education — that is, emphasizing that the number one cause of death in women is cardiovascular disease. It may happen five or ten years later than men, but it happens at the same rate. Women are not protected from it. One out of three women will die of heart disease; one out of eight women will die of breast cancer. They can’t hear that enough.

Is losing weight one of the most effective ways to reduce one’s cardiac risk?

Dr. Butte: Losing weight improves your lipid profile, blood pressure and the risk of sleep apnea, which in turn causes other problems. Also, when people with atrial fibrillation lose 20-30 pounds, their risk for stroke goes down. Losing weight is a challenge, but we know it’s not enough; you also need to exercise. I mention the metabolic syndrome — the risk factors that increase your chance of having a heart attack — to my patients.

Dr. Dyda: The tough cases are people who are obese and also have diabetes. Once someone has diabetes and cardiovascular disease, that’s a game-changer. Their disease process tends to be more aggressive, and their mortality rate is a lot higher. People with diabetes are at greater risk of developing cardiovascular disease in general. It’s a function of the hyperglycemia — elevated blood sugar — as well as the altered metabolism and hypertension. They are all tied together.

Are people surprised at how cardiac devices, such as pacemakers, have progressed?

Dr. Kim: Yes, but today they are very common; approximately 250,000 pacemakers are implanted in the U.S. annually. As people age, they may not be able to generate the appropriate electrical impulses, which can result in a slowing of the heartbeat and symptoms of lightheadedness, shortness of breath or passing out. Pacemakers are effective at managing the electrical function.

Approximately 150,000 implantable cardioverter-defibrillators, known as ICDs, are implanted annually in patients with heart failure. People with a weakened heart muscle are at higher risk for a heart arrhythmia that can result in cardiac death. An important large trial found a 30 percent reduction in mortality among those who meet the criteria for benefiting from an ICD. Also, for people with heart failure who also have a conduction abnormality resulting in asynchronous activation of the heart, we can add an additional lead that activates the left and right sides of the heart simultaneously. This is shown to reduce hospitalization and mortality.

Dr. Butte: I would like to add that people with one of these devices can now have an MRI scan. This is huge progress.

Is there news relative to cardiac stents?

Dr. Butte: The second-generation drug-eluting stents, which slowly release a drug that keeps the artery open, are very good. They work well and are easy to deliver. But they’re not foolproof, because the metal stent remains in place, which means there is a slight risk for restenosis, where a clot forms in the stented artery. Coming next are bioabsorbable stents — stents that slowly dissolve. They’re not quite ready for prime time.

Dr. Dyda: The other thing with stents is that, for people who are at too high a risk for coronary bypass surgery, we are being a little bit more aggressive with stenting — something we might not have done previously. But we know this treatment can alleviate symptoms, decrease angina and improve their quality of life. For those who have diseased aortic valves and are not good candidates for surgery, we now have transaortic valve replacements (TAVR) — a breakthrough that is much easier for patients.

Are there any new heart medications?

Dr. Butte: We have just been presented with the recent data on the PCSK9 inhibitors, a new class of drugs that can dramatically lower LDL cholesterol levels, and these drugs were shown to significantly decrease heart attacks, strokes and cardiovascular deaths. Many people cannot take statin drugs, such as Lipitor.

Dr. Greene: The PCSK9 inhibitors will also be useful for patients who take statins but don’t get the desired response. If you had a heart attack, and you’re on a cholesterol pill that isn’t lowering your cholesterol very much, this might be good adjunctive therapy for you. Also, we now have empagliflozin, the first diabetes drug that also addresses heart disease.

Dr. Dyda: One of the most exciting new medications is Entresto for heart failure. We finally have a drug that, for certain people with symptomatic heart failure, provides a clear survival benefit. This is an improvement over the medications we previously prescribed. Also, the new anticoagulants appear to be as good or even better than Coumadin at stroke prevention while reducing complications, such as bleeding.

Dr. Butte: I would add that we do not have a medication that is broadly effective for patients with atrial fibrillation. There are procedures that are successful, and we now have the Watchman device, which has a role to play for people who cannot take bloodthinning medication. It reduces the chance of stroke. But I am hopeful that an effective medication for atrial fibrillation will become available.