Medical Bulletin 27/ December/ 2024

Researchers from the City University of Hong Kong unveiled their work in wearable technology in SmartMat. Their study provides a comprehensive overview of the latest advancements in wearable heart sound sensors, examining sensor types, material innovations, design principles, denoising techniques, and clinical applications. The research demonstrates how technological innovations can bridge gaps in cardiac health monitoring.

The review highlights a transformative journey from traditional stethoscopes to state-of-the-art wearable sensors that enable continuous cardiac activity monitoring. Key innovations include the development of mechanoacoustic sensors with soft, flexible designs that prioritize user comfort while maintaining high sensitivity and specificity. The research emphasizes the importance of advanced materials and optimized design principles in addressing these challenges. Denoising techniques are also spotlighted as crucial for accurate heart sound analysis, tackling the low-frequency nature of cardiac sounds and their vulnerability to environmental interference. Additionally, the study delves into the clinical applications of these sensors, envisioning a future where personalized healthcare and remote monitoring are seamlessly integrated into cardiovascular disease management. The findings pave the way for actionable, real-time insights that could significantly enhance patient outcomes and healthcare efficiency.

"Our work on wearable heart sound devices marks a significant step forward in the early detection and monitoring of cardiovascular diseases," says Dr. Bee Luan Khoo, Associate Professor at the City University of Hong Kong and a leading researcher in the field. "These devices have the potential to provide more accurate, real-time cardiac health data, revolutionizing the way we manage and understand heart health."

Reference: Ahmad RuS, Khan MS, Hilal ME, Khan B, Zhang Y, Khoo BL. Advancements in wearable heart sounds devices for the monitoring of cardiovascular diseases. SmartMat. 2024;e1311. doi:10.1002/smm2.1311

The research team at the Korea Institute of Science and Technology along with Dr. Indong Jun from KIST Europe, has developed a novel stent surface treatment technology using laser patterning. This technology promotes endothelial cell growth while inhibiting smooth muscle cell dedifferentiation in blood vessels. By controlling cellular responses to nanostructured patterns, the technique holds promise for enhancing vascular recovery, especially when combined with chemical coating methods.

The research team applied nanosecond laser texturing technology to create nano- and micro-scale wrinkle patterns on nickel-titanium alloy surfaces. The wrinkle patterns inhibit the migration and morphological changes of smooth muscle cells caused by stent-induced vascular wall injury, preventing restenosis. The wrinkle patterns also enhance cellular adhesion, promoting re-endothelialization to restore the vascular lining.

The team validated the effectiveness of this technology through in vitro vascular cell studies and ex vivo angiogenesis assays using fetal animal bones. The laser-textured metal surfaces created favorable environments for endothelial cell proliferation while effectively suppressing smooth muscle cell dedifferentiation and excessive growth. Notably, smooth muscle cell growth on the wrinkled surfaces was reduced by approximately 75%, while angiogenesis increased more than twofold.

The surface patterning technology is expected to be applicable not only to metal stents but also to biodegradable stents. When applied to biodegradable stents, the patterns can prevent restenosis and enhance endothelialization before the stents dissolve, improving treatment outcomes and reducing complication risks.

Dr. Jeon stated, “This study demonstrates the potential of surface patterns to selectively control vascular cell responses without drugs. Using widely industrialized nanosecond lasers allows for precise and rapid stent surface processing, offering significant advantages for commercialization and process efficiency.”

Reference: Jun, I., Choi, H., Kim, H., Choi, B. C., Chang, H. J., Kim, Y., ... & Jeon, H. (2025). Exploring the potential of laser-textured metal alloys: Fine-tuning vascular cells responses through in vitro and ex vivo analysis. Bioactive Materials, 43, 181-194.

A research team has unveiled an innovative technique to convert fibroblasts—common connective tissue cells—into mature and functional induced cardiomyocytes (iCMs). Their method relies on combining fibroblast growth factor 4 (FGF4) with vitamin C, a pairing that accelerates cell maturation and enhances function. The findings are published in experimental and molecular medicine.

“Our findings bring us closer to transforming regenerative medicine into practical therapies,” says Dr. Song, who is based at Korea University’s Department of Cardiology and in Seoul, South Korea. “This research takes an important step toward using a patient’s own cells to repair their heart.” Direct cardiac reprogramming, a process that bypasses the intermediate stem cell stage, allows fibroblasts to be converted into induced cardiomyocytes. While this approach holds significant promise, scientists have struggled to produce mature and fully functional cardiomyocytes. The Korea University team addressed this hurdle by activating a critical cellular mechanism: the JAK2–STAT3 signaling pathway.

Through their research, the scientists employed advanced techniques like RNA sequencing, fluorescence imaging, and electrophysiological testing. Their results revealed key improvements: better cell structure with well-defined sarcomeres and T-tubules, enhanced electrical activity with improved ion channel function, and a higher efficiency in generating mature, fully reprogrammed cardiomyocytes.

By promoting mature cardiomyocytes from a patient’s own tissue, it may one day be possible to repair damage from heart attacks or other cardiovascular conditions. Such an approach could reduce reliance on heart transplants and potentially revolutionize treatments for millions of patients.

Reference: Jun, S., Song, MH., Choi, SC. et al. FGF4 and ascorbic acid enhance the maturation of induced cardiomyocytes by activating JAK2–STAT3 signaling. Exp Mol Med 56, 2231–2245 (2024). https://doi.org/10.1038/s12276-024-01321-z

A new scan method for lung scanning has enabled the team, led by researchers at Newcastle University, UK, to see how air moves in and out of the lungs as people take a breath in patients with asthma, chronic obstructive pulmonary disease (COPD), and patients who have received a lung transplant. The findings are published in Radiology.

Publishing two complementary papers in Radiology and JHLT Open, the team explain how they use a special gas, called perfluoropropane, that can be seen on an MRI scanner. The gas can be safely breathed in and out by patients, and then scans taken to look at where in the lungs the gas has reached.

Using the new scanning method, the team are able to reveal the parts of the lung that air doesn't reach properly during breathing. By measuring how much of the lung is well-ventilated and how much is poorly ventilated, experts can make an assessment of the effects of a patient's respiratory disease, and they can locate and visualise the lung regions with ventilation defects.

The new scanning technique allows the team to quantify the degree of improvement in ventilation when patients have a treatment, in this case a widely used inhaler, the bronchodilator, salbutamol.

A further study, published in JHLT Open, examined patients who had previously received a lung transplant for very severe lung disease.

The team scanned transplant recipients' lungs over multiple breaths in and out, collecting MRI pictures that show how the air containing the gas reached different areas of the lung. The team scanned those who either had normal lung function or who were experiencing chronic rejection after lung transplant, which is a common issue in lung transplant recipients as their immune system attacks the donor lungs. In those with chronic rejection, the scans showed poorer movement of air to the edges of the lungs, most likely due to damage in the very small breathing tubes (airways) in the lung, a feature typical of chronic rejection also known as chronic lung allograft dysfunction.

Reference: https://www.ncl.ac.uk/press/articles/latest/2024/12/newscanmethodunveilslungfunctionsecrets/