Abstract 4369956: A Single Parasternal-long-axis-view-sweep of the Heart (SPLASH) + color Doppler Screening Protocol for the Detection of Hypertrophic Cardiomyopathy

Abstract

Background: Hypertrophic cardiomyopathy (HCM) is the most common heritable cardiac disease, yet it remains profoundly underdiagnosed; it is estimated that 6 out of 7 (86%) individuals with HCM have not been identified and are unaware of their diagnosis. HCM is typically diagnosed using routine echocardiography. However, the cost, time to perform each study, need for patient privacy, and inherent issues with transporting large echocardiogram machines, has limited the use of echocardiography for wide-scale community-based screening. Hypothesis: Given that the parasternal long axis (PLAx) view can visualize many of the characteristic findings seen in HCM, we hypothesized that a streamlined, cost-effective approach to the diagnosis of HCM would utilize a point-of-care echo probe for obtaining a single PLAx sweep of the heart (SPLASH) + color Doppler to screen for HCM. Here we report the sensitivity and specificity of our SPLASH screening. Methods: We studied 108 consecutive patients presenting to our echocardiography laboratory for exercise stress testing on days that HCM patients and patients with chronic kidney disease (CKD) and end stage renal disease are routinely screened. SPLASH echocardiograms were performed by an experienced sonographer. Each was read independently in random order by 2 echo attendings and 2 independent sonographers, all blinded to patient diagnosis. Results were categorized as definite HCM, probable HCM, possible HCM, probably not HCM, and no evidence of HCM. Readers also indicated whether obtaining additional views for further assessment was indicated. Results were compared to the gold standard of full echocardiographic result combined with clinical diagnosis. Results: The mean age of the cohort was 57.3 years (53% women; 22% self-reported as Black). 63% had hypertension and 35% had CKD. Time to perform one SPLASH study was, on average, less than 5 minutes. Specificity of the SPLASH was 91.0% for attendings and 83.7% for sonographers. Sensitivity was 84.5% for attendings and 85% for sonographers. When the studies that the reader indicated needed additional views for further assessment were included, the sensitivity increased to 92.5%. Conclusions: We report a novel and streamlined method for performing echocardiographic screening for HCM with high sensitivity and specificity. If validated in community settings, this method has the potential to change medical practice and improve access to rapid yet accurate diagnostic testing for HCM.