Scientists have developed a new technique that could lower the risk of stroke in people with atrial fibrillation, a heart rhythm disorder affecting millions. The method involves injecting a magnetically guided liquid into the heart that hardens to seal a small pouch called the left atrial appendage, where blood clots often form.
Atrial fibrillation causes the heart's upper chambers to beat chaotically, allowing blood to pool in the left atrial appendage and potentially clot. If a clot travels to the brain, it can cause a stroke. Current treatments include blood-thinning drugs, which increase bleeding risk, and implantable devices that may not seal completely or can damage heart tissue.
The new approach, tested only in animals so far, uses a magnetofluid injected via catheter into the appendage. An external magnetic field holds the liquid in place, and within minutes it reacts with blood to form a soft gel that seals the cavity. Because it starts as a liquid, it adapts to the irregular shape of each patient's appendage, potentially creating a more complete seal than rigid implants.
In pig studies, the magnetogel remained stable for 10 months with no clots or leakage, and the heart's inner lining grew over it smoothly. Compared with conventional metal devices, the gel caused less tissue damage and produced a smoother surface. However, the technique is still experimental and has not been tested in humans.
