The study hinges on the early detection of atrial fibrillation (AFib), which is an irregular heart rhythm that causes poor blood flow and is a leading cause of stroke. While the link between atrial fibrillation and stroke is thoroughly understood, AFib has very few warning signs, making it difficult to diagnose until a stroke occurs. Johnson & Johnson and Apple are hoping that apps and the Apple Watch’s electrocardiogram (ECG) features will help detect AFib before a stroke occurs. This trial follows a Stanford study that found that the Apple Watch’s irregular heart rate monitoring features are accurate enough to use in a medical setting.

Since this is a virtual trial, participants don’t have to travel to a clinical trial site — they can partake remotely via a proprietary app. The Heartline study could help prevent strokes and deaths — AFib leads to 158,000 deaths per year — and could lead the way toward a new approach to clinical trials that leverage greater sample sizes and more consistent reporting. Those interested in participating can sign up at Heartline.com.

Dialysis replicates some of the kidney’s key functions, but it requires a machine that pulls blood out of a blood vessel, filters it and pumps it back into the body. Typically, an extra blood vessel — either synthetic or donated — is implanted into the patient’s arm, and that channels blood into the dialysis machine. But a new method is heading to clinical trials, and it would allow the patient’s own cells to create that extra blood vessel.

The researchers behind this work lined a biodegradable polymer tube with vascular cells from a deceased donor. For eight weeks, the cells multiplied and formed a new tube while the polymer scaffolding broke down. The researchers then took the cellular tube and implanted it into a patient’s arm. All told, 60 patients participated. Gradually, their cells migrated into the tubes and multiplied to create mature blood vessels — though that took between one and two years.

The process is similar to the one by medical device company Aditlys that we reported on last year. Aditlys hopes to implant a polymer tube into a person’s arm. The patient’s cells would form a new blood vessel around the synthetic tube, which would then dissolve. According to the company’s website, that project is entering its final phase. It’s hard to say which solution might hit the market first, but if these clinical trials are a success, the hundreds of thousands of dialysis patients in the US could eventually have more options.