Wearable devices have become small, sophisticated and stylish, to the extent that smart rings are now highly-effective remote monitoring devices for health and fitness measurements.
The CART-I (Cardio tracker) ring from preventive healthcare company Sky Labs harnesses the latest technologies to offer continuous remote monitoring and has been shown to help in the detection of the heart irregularity Atrial Fibrillation (AF).
But as with any wearable monitoring device, it is crucial that it fits properly and is worn correctly, in order to deliver the most effective, appropriate, and accurate levels of data.
Range of sizes
Recognising that a ring is often a bespoke item for wearers, and not a one-size-fits-all piece of jewellery, the CART-I is available in a range of eight different sizes, offering the best possible fit for people with different finger measurements.
This is important because CART-I – the world’s first ring-type smart wearable heart rhythm monitoring medical device – utilises photoplethysmography (PPG) signals to measure heart rate from screening the bloodstream 24/7 through the wearer’s finger.
PPG measures the amount of light that is absorbed or reflected by blood vessels in living tissue and is regarded as an effective low-cost technology that can be applied to various aspects of cardiovascular monitoring.
The ring also uses electrocardiogram (ECG) signals to provide additional, and more precise, cardiac information to the user’s doctor, often without user intervention, if necessary.
The ring transmits all the data gathered from the finger to a cloud platform where Artificial Intelligence (AI) technology detects and analyses AF.
The system allows the heart to be monitored easily in daily life by people who have suffered from AF, or have a family history of AF.
The finger is acknowledged as providing greater sensitivity for the sensors, with more accurate and better signal quality, compared to other parts of the body such as the earlobe or wrist, and is recognised as an ideal measurement site for blood flow.
That is because the finger has a higher volume of atrial blood flow, the smallest pulse peak time and reflection index, provides highest amplitude, and has better signal quality.
Also, wearing a ring on the finger continuously is more convenient than wearing a wristband for a whole day.
Choosing a ring
When choosing a ring, wearers should sample one that is comfortable and not too tight but also not spinning on the finger.
If it is overly tight, it will put pressure on the blood vessels and cause reduced blood flow, while if it is too loose, the sensor will be unable to detect blood flow in the vessel.
To measure correct blood flow, the proper tightness is critical and underlines: the importance of ring size; of having a comfortable fit; and choosing a product such as the CART-I where there is a range of sizes available.
Sky Labs’ CART-I offers a finger-size measuring facility before purchase to ensure a good fit, and deliver the most accurate monitoring from the ring, which is made of surgical steel, weighs around 4 grams, is dustproof and waterproof, and can last up to 48 hours per charge.
Smart rings have the technology to gather continuous, real-time, data on various body indicators such as heart rate, and also being able to accurately measure blood pressure outside of a clinical setting.
They are proving of particular value in detection of AF, because of the continuous monitoring aspect, as the condition remains relatively difficult to diagnose and symptoms can be intermittent.