From the 2018 HVPAA National Conference
Samreen Raza (University of Texas), Rebecca Vigen (University of Texas Southwestern Medical Center), Susan Matulevicius (University of Texas Southwestern Medical Center, Dallas, TX;)
Focused cardiac ultrasound (FCU) is the use of portable ultrasound-devices to rapidly answer clinical questions. Advantages include easy use/portability. Chemotherapy-related cardiotoxicity detection requires serial echocardiography which is resource intensive/burdensome for patients. It is unknown whether FCU can be used to screen for this using advanced practice providers (APPs).
The goal of this study is to determine if FCU can be used to reliably evaluate left ventricular function (LVEF) by an APP to assess for chemotherapy-related cardiotoxicity in Oncology patients. Second objective is to determine if use of this technology was feasible at our institution to impact patient care and establish workflow with an interdisciplinary team. Overall objectives were to determine if we can use this to improve diagnostic services for echocardiography and decrease delays in patient care.
The study was conducted at in the outpatient echocardiography lab and the Oncology clinic at Parkland Memorial Hospital and was divided into three phases. First, an Oncology APP was trained on the use of FCU and LVEF analysis using the Simpson’s Biplane technique. The initial training phase included didactic sessions and scanning with the Sonosite iViz device. The APP was trained to obtained standard 2D views for LVEF assessment. The APP was trained on EF interpretation using Philips Xcelera software. Subsequent LVEF assessment was performed by all blinded observers using TomTec (TomTec Imaging Systems, Germany). The LVEF assessment from these studies were compared to sonographer echocardiograms performed on the same day. LVEF was assessed by a Cardiologist and considered the gold standard. The studies were analyzed by two separate blinded experienced cardiologists and the degree of correlation was analyzed. Linear regression modeling to analyze correlation between EF interpretation between all blinded observers and Bland Altman analysis was performed. Image quality was evaluated for all Handheld FoCUS images by a single blinded cardiologist and segmental endocardial border delineation was scored (IQ score: 2= good, 1= poor, 0=uninterpretable).
A total of 91 patients were scanned in Phase I of the study and a total of 126 patients data was analyzed for EF. The correlation coefficient between cardiologists was r=0.93. The correlation between cardiologist and APP was r=0.77 for Level III echocardiographer and 0.78 for level II. The correlation between APP and LVEF gold standard was r=0.77. The correlation between experienced echocardiographers interpreting FoCUS acquired images was r=0.87. The correlation between TomTec analysis for EF between Cardiologist and APP was r=0.70 for Phase I. All images were determined to be interpretable with >60% reported as good quality with an IQ score of 2.
There was good correlation between experienced echocardiographers with respect to EF analysis. There was also reasonably good correlation between APP and experienced echocardiographers for EF analysis. Image quality from Handheld devices was found acceptable for clinical interpretation. This study demonstrates that it is feasible to train an APP on obtaining images for EF analysis and they can be trained on EF interpretation with good correlation with experienced echocardiographers.
Implications for the Patient
Implications of our work include reducing cost/delay in chemotherapy times for patients in an urban safety-net hospital environment with significant clinical impact on cost/clinical outcomes and potential to streamline future care. We have established a workflow system to enable use of portable hand-held ultrasound technology at our academic institution.