'Smartphone app better at measuring blood flow'

A smartphone app using the phone's camera has performed better than traditional physical examination to assess blood flow in patients undergoing coronary angiography, scientists said today.

The findings, published in Canadian Medical Association Journal, highlight the potential of smartphone applications to help physicians make decisions at the bedside.

"Because of the widespread availability of smartphones, they are being used increasingly as point-of-care diagnostics in clinical settings with minimal or no cost," said Benjamin Hibbert from the University of Ottawa in Canada.

"For example, built-in cameras with dedicated software or photodiode sensors using infrared light-emitting diodes have the potential to render smartphones into functional plethysmographs (device that measures changes in blood flow), " said Hibbert.

Researchers compared the use of a heart-rate monitoring application with the modified Allen test, which measures blood flow in the radial and ulnar arteries of the wrist, one of which is used to access the heart for coronary angiography.

A total of 438 participants were split into two groups; one group was assessed using the app and the other was assessed using a gold-standard traditional physical examination (known as the Allen test).

The smartphone app had a diagnostic accuracy of 94 per cent compared with 84 per cent using the traditional method.

"The current report highlights that a smartphone application can outperform the current standard of care and provide incremental diagnostic yield in clinical practice," said Hibbert.

"However, while they are not designed as medical devices, it is important that they are evaluated in the same rigorous manner by which we assess all therapies and diagnostic tests," said Pietro Di Santo, lead author of the study.

"Although this application is not certified at present for use in health care by any regulatory body, our study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient's bedside," Hibbert added.