Nearly 200 years after the introduction of the stethoscope, the accuracy of a pocket ultrasound device that enables a physician to “look” at a patient’s heart during routine physical exams has been validated for the first time in peer-reviewed research led by Scripps Translational Science Institute (STSI) and Scripps Health.
Roughly the size of a smart phone, the Vscan pocket ultrasound used for point of care assessment of heart health could significantly reduce costs from traditional echocardiograms and improve the quality of care. Research was published in the July 5 issue of the Annals of Internal Medicine.
“Pocket echos used during physical examinations may have the potential to reduce the number of unnecessary echocardiograms, particularly when used by a clinician trained in obtaining and interpreting the images,” said Dr Eric J Topol, cardiologist at Scripps Clinic, chief academic officer at Scripps Health, director of Scripps Translational Science Institute and principal investigator on the study. “Approximately 20 million echocardiograms are conducted in the US every year, each costing $ 1,500 or more and requiring a return appointment for a hospital or clinic echo laboratory for an extended session of about 45 minutes. A pocket echocardiogram could significantly reduce costs and improve the quality of the patient experience.”
Research showed that Vscan provided accurate assessments of ejection fraction, a measurement of how well the heart is pumping, and other measures for assessing heart health in patients. In the study, physicians evaluated the hearts of 97 patients using the Vscan pocket ultrasound device to visually assess various heart structures within a five-minute timeframe in order to simulate the length of time of a physical examination. Conclusions drawn from these imaging results were compared to conclusions drawn from imaging results also obtained from standard transthoracic echocardiography (TTE) machines. The study evaluated the ability of the observer to visualize heart structures as well as accuracy in interpreting the images. The study also calculated difference in accuracy between cardiology attending physicians and less experienced cardiology fellows with two months or less training in echocardiographic interpretation.
“The traditional stethoscope was invented in 1816, but that instrument is more accurately described as a ‘stethophone’ as it only allows us to listen rather than look at the heart. The Vscan allows the doctor and patient together to look at the patient’s heart during a routine physical exam,” said Dr Topol. “The echocardiogram and other current imaging techniques offer a view inside the chest, however, these are big expensive machines that require a significant amount of time to get test results. A convenient pocket device could provide doctors and patients with important information about heart health immediately, right at the point of care.”
In the study, pocket ultrasound images were adequate for visualizing ejection fraction 95 percent of the time, wall motion abnormality 83 percent of the time, left ventricular end-diastolic dimension 95 percent of the time, pericardial effusion 94 percent of the time, mitral valve 90 percent of the time, aortic valve 82 percent of the time, and inferior vena cava (the large vein carrying blood to the heart) size 75 percent of the time. Accuracy of interpretation of pocket ultrasound images was highest when assessing ejection fraction and aortic valve, and lowest when assessing inferior vena cava size. Accuracy and between-physician agreement was higher for experienced cardiologists than for less experienced cardiology fellows.
“Cardiologists rarely review echocardiogram images with their patients. With this pocket ultrasound device, a cardiologist can educate a patient about his or her heart condition while looking at real-time images, restoring a more intimate doctor-patient experience,” added Dr Topol. “Looking ahead, medical schools might one day be giving these devices to students on their first day of school to become facile with pocket ultrasound as a powerful imaging tool which in many ways will replace the traditional stethoscope.”
This study is an extension of Scripps’ leadership in heart care and research. Scripps recently broke ground on the $ 456 million Scripps Cardiovascular Institute (SCI), a centre for innovation that will bring together top researchers, physicians and staff. SCI will incorporate leading-edge wireless technologies and individualized medicine for the best in patient care when it opens in 2015. Annually, more than 55,000 patients receive their cardiovascular care from Scripps, making it San Diego County’s largest heart care provider. Scripps is the region’s only cardiovascular programme consistently recognized by US News & World Report as one of the best in the country.
Vscan manufacturer General Electric provided no funding for the study. The study was funded by the National Institutes of Health’s flagship Clinical and Translational Science Award grant awarded to The Scripps Research Institute, which then partnered with Scripps Translational Science Institute.
Scripps Translational Science Institute (STSI) is an initiative of Scripps Health, in collaboration with The Scripps Research Institute. STSI initiates research designed to help move basic research from the lab to the patient bedside, bridging the gap between basic science and clinical trials. It aims to replace the status-quo of one-size-fits-all-medicine with individualized health care that is based on the known genetic factors influencing health and disease and that takes advantage of advances in digital technology for real-time health monitoring.