Scientists at the University of Chicago have developed a new pacemaker that’s thinner than a human hair, wireless and operated entirely by light from an optic fiber. The non-invasive device could help regulate heart activity or even stimulate neurons in a set pattern to treat symptoms of conditions like Parkinson’s.
The heart pumps thanks to a series of very carefully timed electrical signals, but if those signals fall out of time, they can lead to all sorts of issues, such as strokes, heart attacks or even a fatal failure of the organ. Pacemakers monitor and correct these abnormal rhythms, but they require invasive surgeries and bring their own risks.
The new device is much less invasive – it’s a thin film just one micrometer thick, which is about 100 times thinner than a human hair, or a recent similar device made of graphene which was also 100 micrometers thick. It tips the scales at just one 50th of a gram, making it 250 times lighter than a regular pacemaker. And rather than needing a battery, it’s powered by light.
More than 80% of stroke survivors experience walking difficulty, significantly impacting their daily lives, independence, and overall quality of life. Now, new research from the University of Massachusetts Amherst pushes forward the bounds of stroke recovery with a unique robotic hip exoskeleton designed as a training tool to improve walking function.
This invites the possibility of new therapies that are more accessible and easier to translate from practice to daily life compared to current rehabilitation methods.
Following a stroke, people often experience walking asymmetry, where one step is shorter than the other. The study, published in IEEE Transactions on Neural Systems and Rehabilitation Engineering, reveals that the robotic hip exoskeleton has the potential to effectively train individuals to modify their walking asymmetry, presenting a promising avenue for stroke rehabilitation.
Myocarditis game-changer: We've blamed the wrong culprit
By Paul McClure
March 07, 2024
Inflammation resulting from a viral infection has traditionally been thought to cause acute myocarditis, which can lead to fatal heart arrhythmias in otherwise healthy young adults. Now, a new study has shown for the first time that the virus itself damages heart cells before inflammation sets in, challenging traditional assumptions.
Viral infections are the most frequent cause of acute inflammation of the heart muscle or myocarditis, a condition linked to up to 42% of sudden cardiac deaths in young adults. The common cold (adenovirus), hepatitis B and C, and parvovirus have all been associated with myocarditis.
The traditional explanation for what causes myocarditis focuses on inflammation, triggered by the body’s immune response to a virus, which leads to potentially fatal rapid or irregular heart rhythms called arrhythmias. However, a new study led by researchers at the Fralin Biomedical Research Institute at Virginia Tech may have just turned tradition on its head, finding that the virus itself damages heart muscle before the onset of inflammation.
Heparin, the world's most widely used blood thinner, is used during procedures ranging from kidney dialysis to open heart surgery. Currently, heparin is derived from pig intestines, but scientists at Rensselaer Polytechnic Institute (RPI) have discovered how to make it in the lab. They have also developed a path to a biomanufacturing process that could potentially revolutionize how the world gets its supply of this crucial medicine.
"In recent years, with disease and contamination issues disrupting the global supply chain of pig heparin and potentially putting millions of patients at risk, it's clear we need to diversify the way we make this drug," said Jonathan Dordick, Ph.D., Institute Professor of Chemical and Biological Engineering, and vice president of Strategic Alliances and Translation at RPI. "Our work will make it possible to manufacture heparin that is both consistently available and safe."
A team of engineers led by the University of Massachusetts Amherst and including colleagues from the Massachusetts Institute of Technology (MIT) recently announced in Nature Communications that they had successfully built a tissue-like bioelectronic mesh system integrated with an array of atom-thin graphene sensors that can simultaneously measure both the electrical signal and the physical movement of cells in lab-grown human cardiac tissue.
In a research first, this tissue-like mesh can grow along with the cardiac cells, allowing researchers to observe how the heart's mechanical and electrical functions change during the developmental process. The new device is a boon for those studying cardiac disease as well as those studying the potentially toxic side effects of many common drug therapies.
University of Virginia School of Medicine researchers have discovered a gene on the Y chromosome that contributes to the greater incidence of heart failure in men. The work is published in the journal Nature Cardiovascular Research.
Y chromosome loss in men occurs progressively throughout life and can be detected in approximately 40% of 70-year-old men. UVA's Kenneth Walsh, Ph.D., discovered in 2022 that this loss can contribute to heart muscle scarring and lead to deadly heart failure. That finding was the first to directly link Y chromosome loss to a specific harm to men's health; Y chromosome loss is increasingly thought to play a role in diseases ranging from Alzheimer's to cancer.
In an important follow-up finding, Walsh and his team have discovered how Y chromosome loss triggers changes in heart immune cells that make the cells more likely to cause scarring and heart failure.
Further, the researchers found they could reverse the harmful heart changes by giving lab mice a drug that targets the process of fibrosis that leads to the heart scarring, which could lead to a similar treatment for men.
"Our previous work identified that it was loss of the entire Y chromosome that contributed to heart disease in men," said Walsh, the director of UVA's Hematovascular Biology Center. "This new work identified a single gene on the Y chromosome that can account for the disease-promoting effects of Y chromosome loss."
Taking a single pill that combines medications targeting cardiovascular disease-related conditions was shown long ago to lower the risk of death from such causes, including heart attacks and strokes.
The concept of using such "polypills" to prevent and treat atherosclerotic cardiovascular disease was introduced nearly 25 years ago. Shortly thereafter, the strategy was the focus of a seminal modeling study that promoted polypills to reduce cardiovascular disease at the population level. Still, many years and a body of supportive research later, use of such pills remains low throughout the world.
Now, a new study from researchers at Washington University School of Medicine in St. Louis published in Nature Medicine bolsters previous findings and provides additional evidence that polypills are beneficial in preventing heart attacks and strokes and reducing deaths among people with cardiovascular risk factors, including high blood pressure and high cholesterol.
Coronary artery disease and major depression may be genetically linked via inflammatory pathways to an increased risk for cardiomyopathy, a degenerative heart muscle disease, researchers at Vanderbilt University Medical Center and Massachusetts General Hospital have found.
Their report, published April 5 in the journal Nature Mental Health, suggests that drugs prescribed for coronary artery disease and depression, when used in combination, potentially may reduce inflammation and prevent the development of cardiomyopathy.
"This work suggests that chronic low-level inflammation may be a significant contributor to both depression and cardiovascular disease," said the paper's corresponding author, Lea Davis, Ph.D., associate professor of Medicine in the Division of Genetic Medicine and Vanderbilt Genetics Institute.
The connection between depression and other serious health conditions is well known. As many as 44% of patients with coronary artery disease (CAD), the most common form of cardiovascular disease, also have a diagnosis of major depression. Yet the biological relationship between the two conditions remains poorly understood.
App detects heart failure vibes via a smartphone's existing sensors
By Ben Coxworth
April 09, 2024
Detecting the first stages of heart failure could soon be as simple as placing a smartphone on a patient's chest. That's the conclusion of an ongoing study, which is aimed at developing an app for diagnosing the potentially lethal condition as early as possible.
Heart failure may initially present in the form of fatigue upon exertion, or shortness of breath. These symptoms may of course have other, more innocuous causes. And unfortunately, checking to see if they are caused by heart failure currently requires ultrasound heart scans, blood tests or other special procedures.
Scientists from Finland's University of Turku set out to develop a much simpler diagnostic method, that can be quickly performed in a doctor's office without any special equipment. The result is a machine-learning-based app that uses a smartphone's existing accelerometer and gyroscope to measure tiny telltale cardiac vibrations in the patient's chest.
AI trained on simple heart rate data can predict an episode of the most common heart rhythm disorder, atrial fibrillation, 30 minutes in advance, new research has shown. With plans for it to be incorporated into a smartphone so it can analyze data from a smartwatch, the model would act as an early warning system.
The most common heart rhythm disorder, atrial fibrillation (AF), significantly increases emergency department presentations and the risk of other diseases like stroke and dementia. The condition occurs when the heart’s upper chambers (atria) beat chaotically, out of sync with the lower chambers (ventricles), producing an irregular, often very rapid, heart rhythm.
Reverting a patient from AF back to regular sinus rhythm can require intensive interventions such as cardioversion, delivering a low-energy shock to ‘reset’ the heart’s conduction system. (Yes, it’s the same device used in medical programs, accompanied by a cry of “CLEAR!”) So, being able to detect an episode of AF before it happens would enable early interventions that might improve patient outcomes.
Examining long-term outcomes for people with atrial fibrillation (AF), the most common heart rhythm disorder, a new study found that 55% survived to 10 years. The researchers say AF needs to be treated as a chronic illness with serious long-term consequences.
AF, or AFib, and its close medical cousin, atrial flutter, are associated with complications such as stroke, heart failure, and heart attack. While there’s an understandable focus on treating these conditions to prevent acute complications, less research has looked at what’s happening in the long term.
Now, a study led by researchers from the University of Queensland’s (UQ) Faculty of Medicine examined clinical outcomes up to 10 years after an acute hospital admission for AF or atrial flutter. The findings are rather grim.
“AF is the most common heart rhythm disorder and the leading cause of heart-related hospitalizations globally, causing symptoms like palpitations, dizziness, and chest pain,” said Linh Ngo, the study’s lead and corresponding author. “The disorder is closely associated with stroke, but we know much less about the risk of recurrent hospitalizations and other consequences such as heart failure or death.”
A randomized, placebo-controlled clinical trial led by a collaboration between Duke-NUS Medical School, National Heart Center Singapore (NHCS) and Klinikum Nürnberg, Germany, has revealed surprising new insights into how SGLT2 inhibitor drugs, originally developed for diabetes, benefit patients with heart failure.
Contrary to common assumptions, these drugs may improve cardiac outcomes and heart health without acting as diuretics.
Heart failure is a condition where the heart cannot pump enough blood to meet the body's demands, often leading to fluid build-up in tissues and congestion of the blood circulation. This congestion strains the heart and causes symptoms like breathlessness and swelling.
A newly developed molecule, LK-2, could inform new therapies for stroke-related brain injury, find scientists at The Hospital for Sick Children (SickKids).
An ischemic stroke occurs when blood flow to a part of the brain is interrupted, depriving the brain cells of oxygen and nutrients. Without timely treatment, brain cells can die, resulting in permanent damage to the brain and its functions. Stroke is one of the leading causes of death and disability worldwide, affecting millions every year.
An international study published in Nature co-led by Dr. Lu-Yang Wang, a Senior Scientist in the Neurosciences & Mental Health program at SickKids, and clinician scientists at the Shanghai Jiao Tong University School of Medicine, has uncovered a molecule that holds the potential to protect neurons during stroke and prevent stroke-related brain damage.
Since the early 20th century, researchers believed that movements on the right and left sides of the body were controlled by the opposite hemisphere of the brain and that handedness resulted from the dominant side doing a better job at controlling movements.
Nearly 30 years ago, though, a researcher at Penn State proposed the complementary dominance hypothesis—the idea that both hemispheres of the brain contribute to different aspects of movement on both sides of the body. Now, those decades of work—including independent research by other scientists—are informing clinical trials to test new interventions for people who have experienced strokes.
Maglev titanium heart now whirs inside the chest of a live patient
By Michael Franco
July 26, 2024
For the first time, the fully mechanical heart made by BiVACOR, which uses the same technology as high-speed rail lines, has been implanted inside a human being. The feat marks a major step in keeping people alive as they wait for heart transplants.
The total artificial heart (TAH) was implanted as part of an early feasibility study overseen by the US Food and Drug Administration. According to a statement from the Texas Heart Institute where the implantation surgery was carried out, the heart "is a titanium-constructed biventricular rotary blood pump with a single moving part that utilizes a magnetically levitated rotor that pumps the blood and replaces both ventricles of a failing heart."
Laboratory tests show this 3D printed material molds and sticks to organs. Pictured is a porcine heart. Credit: University of Colorado at Boulder
In the quest to develop life-like materials to replace and repair human body parts, scientists face a formidable challenge: Real tissues are often both strong and stretchable and vary in shape and size.
A CU Boulder-led team, in collaboration with researchers at the University of Pennsylvania, has taken a critical step toward cracking that code. They've developed a new way to 3D print material that is at once elastic enough to withstand a heart's persistent beating, tough enough to endure the crushing load placed on joints, and easily shapable to fit a patient's unique defects.
Constipation linked to significantly elevated risk of cardiac events
By Michael Franco
August 19, 2024
Smoking, obesity, and stress. They're all common causes of damaging cardiac events. However, a just-published study says a new culprit should be added to the list of the risks that can hurt our hearts: constipation.
To reach this conclusion, researchers at Monash University in Australia, analyzed health records of individuals in the UK Biobank, an extensive database of 500,000 participants that's been maintained since 2006. The Biobank gathers data from medical imaging, biomarker analysis, and gene sequencing. It also includes information about environmental conditions and lifestyle, including activity levels. Previous analysis of Biobank data has revealed possible genetic markers for loneliness; a link between getting too much light at night and an increased risk of diabetes; how a single night of binge drinking quadruples the risk of liver disease; and much, much more.
