Researchers fight the war against heart disease and stroke in a series of battles on multiple fronts.
The American Heart Association, one of the top funders of heart- and stroke-related research worldwide, has been compiling an annual list of major advances in heart disease and stroke science since 1996. Here are the biggest victories for 2019, grouped into 10 subject areas.
Understanding pulmonary hypertension
Pulmonary hypertension is a type of high blood pressure that occurs when the vessels that carry blood from the heart to the lungs become hard and narrow. Although considered rare, it is becoming more common.
New studies helped reveal how the disease works. One, in the American Journal of Respiratory and Critical Care Medicine, looked at the role of a protein known as BMP9, which was low in people who had a specific type of pulmonary hypertension. Another study, in the AHA journal Circulation, explained how a gene known as BOLA3 plays a crucial role in the disease, opening the door for potential therapies down the road.
Statins help children with inherited high cholesterol levels
The condition known as familial hypercholesterolemia causes high levels of LDL, or "bad," cholesterol and can cause heart attacks at an early age. A long-term study published in the New England Journal of Medicine examined whether cholesterol-lowering statins help children with the condition. It found starting the medication in childhood significantly lowered the risk of heart disease in adulthood.
Older women need physical activity – and even a little helps
The connection between staying active and heart health is no secret. But new work that focused on older women showed how important it is, and how much it takes to make a difference.
A study in Circulation examined the effect of sedentary behavior in a group of women averaging age 79. It found reducing sedentary time by an hour a day equated to a 26% lower risk of heart disease and a 12% lower risk of cardiovascular disease overall. Notably, the activity didn't have to happen all at once – it could be accumulated throughout the day.
Another study, in JAMA Network Open, suggested women who engaged in light physical activity – such as gardening or walking – had a 42% lower risk of heart attack or coronary death than the least-active women. The average age of women in that study also was about 79.
Refining the strategies for controlling blood pressure
The importance of keeping blood pressure within a normal range is well established. Research in the European Heart Journal suggested the best time to take blood pressure medication is at bedtime. People who did so had a 45% lower risk of having or dying from a heart attack, stroke or other cardiovascular problem.
The benefits of lower blood pressure might extend to the brain, according to research published in JAMA. That study of people 50 and older with high blood pressure found lowering systolic pressure – the top number in a reading – to a target of less than 120 millimeters of mercury lowered the risk of mild cognitive impairment compared with lowering blood pressure to less than 140.
Mild cognitive impairment is a risk factor for dementia. And while the study did not find a statistically important lowering of dementia rates, it didn't show an increase. Fear of such an increase had been part of a debate about how aggressively blood pressure should be treated, the researchers noted.
Research with practice-changing results that can save lives
These six studies are leading to a shift in care that the selection committee called "momentous for our patients."
– In December, the Food and Drug Administration approved the use of icosapent ethyl, a prescription form of the omega-3 fatty acid EPA, as an add-on therapy to reduce the risk of cardiovascular events among adults with elevated triglyceride levels. It is sold under the brand name Vascepa.
The approval came on the heels of a study in the New England Journal of Medicine that found the fish oil derivative reduced the risk of having or dying from a stroke or heart-related problem by 25% in people with high triglyceride levels who were taking statins. "I believe this is the biggest thing since statins," Dr. Deepak L. Bhatt, lead author of the study and a cardiologist at Brigham and Women's Hospital, told ABC News.
– A STEMI heart attack happens when a coronary artery is completely blocked. It's commonly treated with a procedure known as percutaneous coronary intervention, or PCI, which involves inserting a balloon or stent to open the clogged artery.
A study published in the New England Journal of Medicine found that when the artery that caused the heart attack was opened along with other partially blocked vessels, patients had a 32% lower risk of another heart attack compared with only clearing the artery that caused the attack.
– People with Type 2 diabetes may be treated with the drug dapagliflozin to lower blood sugar levels. In the New England Journal of Medicine, researchers reported that when given to heart failure patients with a low ejection fraction, including those without diabetes, it kept heart failure from worsening and also reduced the risk of death from overall cardiovascular causes.
– Siri, do I have AFib? A smartwatch can accurately warn about atrial fibrillation, a type of irregular heartbeat, according to a study published in the New England Journal of Medicine. The study, which involved about 419,000 Apple Watch users, found the device accurately detected the condition in more than a third of participants who received notifications of an irregular pulse.
– When someone has an ischemic stroke – the most common type, where a vessel supplying blood to the brain is blocked – fast treatment to inject the clot-busting drug alteplase is considered essential. Generally, it has been thought the drug needed to be used within 4 1/2 hours of the onset of symptoms. But a study in the New England Journal of Medicine suggests some patients might be helped even if they receive the drug up to nine hours after symptoms begin.
– Aortic stenosis is a common and serious heart valve disease. Treatment options include surgery to replace the faulty valve or a minimally invasive approach called transcatheter aortic valve implantation or replacement, also known as TAVI or TAVR. In that procedure, a replacement valve is inserted via a thin tube and placed inside the old valve.
Researchers published findings in the New England Journal of Medicine that showed people with severe aortic stenosis at low surgical risk who had TAVR had lower odds of stroke, rehospitalization and death than those who had surgery.
Dangers for kids and moms-to-be
Add this to the list of reasons why smoking is a bad idea: An analysis in the Journal of the American College of Cardiology found children exposed to secondhand smoke from their parents were at higher risk for a type of irregular heartbeat called atrial fibrillation. For every pack-a-day increase in parental smoking, their children were 18% more likely to develop AFib.
Gestational diabetes – diabetes that develops during pregnancy – might signal future health problems in African American women, according to a study published in the AHA journal Circulation: Cardiovascular Imaging. Among women who reported a previous pregnancy complication, those who had gestational diabetes were most likely to have coronary artery disease that showed up on an angiogram. These same women also were more likely to have Type 2 diabetes. A commentary on the study said it "highlights the importance of inquiring black women about their pregnancy history and incorporating such history into risk assessment and medical care, especially for those with history of gestational diabetes mellitus."
Gene studies expand knowledge
Two studies of the human genome offered new insights into venous thromboembolism, or VTE, and peripheral artery disease, or PAD.
With VTE, which affects 300,000 to 600,000 Americans each year, blood clots start in a vein. A study published in Nature Genetics examined DNA from more than 650,000 people and found 22 new regions of the human genome that correspond with the potentially deadly problem.
In people with PAD, there is a narrowing of the peripheral arteries serving the legs, stomach, arms and head. In Nature Medicine, researchers who tested DNA from more than 637,000 people identified 18 new parts of the genetic code associated with PAD.
A new understanding of heart failure
Heart failure, when the heart does not pump as well as it should, affects more than 6 million Americans. Heart failure with preserved ejection fraction is a type of heart failure where the heart muscle contracts normally but the ventricles do not relax as they should. As published in Nature (and described in the same publication), researchers developed a model of the disease in mice that uncovered a previously unknown driver of heart failure with preserved ejection fraction, which could help lead to new ways to treat it.
Exploring options to treat congenital heart disease
Single-ventricle physiology results from a congenital heart defect. In children born with this syndrome, the pulmonary valve does not form correctly and is sealed, and/or the right ventricle is malformed, meaning blood can't flow from the heart into the pulmonary artery and on to the lungs. Surgery known as the Fontan procedure is sometimes used to treat it.
The results of a clinical trial published in Circulation indicated teenagers who had the procedure as babies saw some improvements in exercise performance after taking the drug udenafil.
Engineering cells to fight heart damage
Cardiac fibrosis, or scarring, is associated with nearly all forms of heart disease. A mouse study in Nature suggests engineered T cells – a type of white blood cell that's part of the immune system – could be used to treat it.
"The idea that cardiovascular disease, the first cause of death in the U.S. and worldwide, could be cured instructing T cells to kill detrimental cells is revolutionary," Dr. Chiara Giannarelli, a cardiologist at Mount Sinai School of Medicine in New York, told The Scientist, although she said more research is needed before it could be used to treat people.