P1850 - Prospective validation of an acoustic-based system for the detection of obstructive coronary artery disease in a high prevalence population(VALIDATE)

Background: Recent guidelines recommend a risk-adjusted non-invasive workup in patients presenting with chest discomfort to support or exclude the diagnosis of stable coronary artery disease (CAD). However, a risk-adjusted diagnostic approach remains challenging in clinical practice. An acoustic detection device for analyzing micro-bruits induced by stenosis-generated turbulence in the coronary circulation has now been developed and has shown potential for ruling out CAD in patients with low to intermediate likelihood.Objective: To examine the diagnostic value of an acoustic detection device in a high-prevalence cohort.Methods: Between 1/2016 and 2/2017, a total of 226 patients without prior invasive coronary angiography (ICA) were prospectively enrolled at two centers and were examined using a portable acoustic detection system. In a double-blinded fashion, the acoustic analysis was performed both prior to ICA with quantitative coronary analysis and following percutaneous coronary intervention (PCI).Results: A CAD score was obtained in 213 of 226 patients (94%). The mean CAD score prior to ICA was 41.2±11.9 in patients with obstructive CAD compared with 33.8±13.4in patients without obstructive CAD (p<0.001). ROC analysis revealed an AUC of 0.661 (95% CI 0.584-0.737) for the diagnosis of obstructive CAD. The sensitivity was 97.6% (95% CI 91.5-99.7%), the specificity was 14.5% (95% CI 9.0-21.7%), the negative predictive value was 90.5% (95% CI 69.6-98.8%), and the positive predictive value was 41.7% (95% CI 34.6-49.0%). Following PCI, a significant decrease in the mean CAD score was observed (38.3±13.7 vs. 40.5±11.2; p=0.039).Conclusion: Use of an acoustic detection device allowed the identification of individuals with CAD in a high-prevalence cohort with a high sensitivity of 97.6% but with a lower specificity. The negative predictive value of 90.5% was within the predicted range for a high-prevalence cohort and could potentially allow a rapid rule-out of obstructive CAD even in a high-prevalence population.