Acomputer-aided auscultation software program, Sensi, used along with an electronic stethoscope, is able to discern between physiological and patho- logical heart murmurs to accuracies of more than 90% and has been developed by South African medical device company Diacoustic Medical Devices.
The program was produced in collaboration with Stellenbosch University’s medical and engineering faculties, says Diacoustic Medical Devices brand manager Alisha Crous.
“Sensi, used together with a Welch Allyn digital stethoscope and a three-lead electro- cardiography device, helps medical examiners to make informed decisions in cardiac diagnosis by providing an analysis of the heart’s sounds,” she explains.
The acoustic signal-processing algorithm identifies different heart sounds in four auscultation locations of the heart: at the apex (mitral), the second right intercostal space (aortic), the second left intercostal space (pulmonary) and the fourth left intercostal space (tricuspid). The heart sounds recorded through the electronic stethoscope are graphically displayed on a screen for the doctor to visually interpret what he/she hears, which gives them more confidence in diagnosing a patient for possible heart murmurs and referrals to a paediatric cardiologist.
Sensi increases examiners’ confidence in diagnosing patients with congenital heart defects when a heart murmur may seem to be either pathological or physiological. Simultaneously, it enhances their clinical practice and doctor-patient relationship as it saves the patient from unnecessary referral costs and emotional stress they might have undergone in the case of an incorrect diagnosis, notes Crous.
“The device has a definite place in the field of cardiac assessment when a mur- mur is noted and the doctor or nurse would like to exclude pathological murmurs, such as murmurs that are caused by a disease or anatomical abnormality in the heart,” says Dr Pieter Fourie, a Western Cape paediatrician, who uses the system, emphasising that Sensi is reliable and accurate but should only be used by someone that has undergone training.
The device has a place in the First and Third Worlds, such as in a highly sophisti- cated hospital in Europe, because of the complexity of referring patients from a town hospital to a cardiac unit, as well as a rural clinic in Africa, where costs and distance become the major obstacles in referring a patient, he explains.
“I would like to encourage the use of new and innovative technology as it becomes increasingly difficult and costly to have access to doctors and hospitals. The proviso is that the user understands the technology and can use it appropriately,” he says.
The Sensi system was built by combining six specialised decision networks to detect the different types of murmurs that occur for congenital heart defect patients. These networks have each been trained using real data, captured in a real-world clinical environment, to closely match the way it is intended to be used when a patient is undergoing a cardiac examination, Diacoustic Medical Devices reports.
The software addresses the need for timely detection in patients and also for patients who live in areas where no specialist is available. Sensi delivers a simple, com- puter-assisted aid to help each examiner make informed decisions in a timely manner, especially at high heart rates where the physician was previously unable to auscultate, for example up to 180 beats a minute.
Unlike vision and hearing screenings, computer-aided auscultation is not intended for use on every patient but only when the primary care physician hears a suspicious murmur. Given the high incidence of heart murmurs in the paediatric population, it should only be used when a murmur is suspect to make an informed referral decision, taking into account the medical history of the patient.
Healthcare providers must be compensated for this improvement in clinical service and it is recommended that the reimbursement must be in line with similar diagnostic tools, like lung function, and sight and hearing testing of paediatric patients, the Sensi White Paper states.
The Sensi device received US Food and Drug Administration 510(k) clearance on July 1, meaning that the device is viewed as ‘valid, safe and effective’ to market and use on patients within the US.
Source: Engineering News.com
Date: 2 September 2011