Samuel Emil Schmidt1, Lene Helleskov Madsen2, John Hansen3, Henrik Zimmermann3, Henning Kelbæk4, Simon Winter2, Dorte Hammershøi5,6, Egon Toft5,6, Johannes Jan Struijk3, Peter Clemmensen7,8. 1. Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7 E4-213, 9220, Aalborg, Denmark. sschmidt@hst.aau.dk. 2. Department of Cardiology, Hospital Unit West, Herning, Denmark. 3. Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7 E4-213, 9220, Aalborg, Denmark. 4. Department of Cardiology, Zealand University Hospital, Køge, Denmark. 5. Department of Electronic Systems, Aalborg University, Aalborg, Denmark. 6. Aalborg University Hospital, Aalborg, Denmark. 7. Department of Cardiology, University Heart Center Hamburg-Eppendorf, Hamburg, Germany. 8. Department of Medicine, Institute of Regional Health Research, Nykoebing F Hospital, University of Southern Denmark, Odense, Denmark.
Abstract
OBJECTIVES: Previous studies have observed an increase in low frequency diastolic heart sounds in patients with coronary artery disease (CAD). The aim was to develop and validate a diagnostic, computerized acoustic CAD-score based on heart sounds for the non-invasive detection of CAD. METHODS: Prospective study enrolling 463 patients referred for elective coronary angiography. Pre-procedure non-invasive recordings of heart sounds were obtained using a novel acoustic sensor. A CAD-score was defined as the power ratio between the 10-90 Hz frequency spectrum and the 90-300 Hz frequency spectrum of the mid-diastolic heart sound. Quantitative coronary angiography analysis was performed by a blinded core laboratory and patients grouped according to the results: obstructive CAD defined by the presence of at least one ≥ 50% stenosis, non-obstructive CAD as patients with a maximal stenosis in the 25-50% interval and non-CAD as no coronary lesions exceeding 25%. We excluded patients with potential confounders or incomplete data (n = 245). To avoid over-fitting the final cohort of 218 patients was randomly divided into to a training group for development (n = 127) and a validation group (n = 91). RESULTS: In both the training and the validation group the CAD-score was significantly increased in CAD patients compared to non-CAD patients (p < 0.0001). In the validation group the area under the receiver-operating curve was 77% (95% CI 63-91%). Sensitivity was 71% (95% CI 59-82%) and specificity 64% (95% CI 45-83%). CONCLUSION: The acoustic CAD-score is a new, inexpensive, non-invasive method to detect CAD, which may supplement clinical risk stratification and reduce the need for subsequent non-invasive and invasive testing.
OBJECTIVES: Previous studies have observed an increase in low frequency diastolic heart sounds in patients with coronary artery disease (CAD). The aim was to develop and validate a diagnostic, computerized acoustic CAD-score based on heart sounds for the non-invasive detection of CAD. METHODS: Prospective study enrolling 463 patients referred for elective coronary angiography. Pre-procedure non-invasive recordings of heart sounds were obtained using a novel acoustic sensor. A CAD-score was defined as the power ratio between the 10-90 Hz frequency spectrum and the 90-300 Hz frequency spectrum of the mid-diastolic heart sound. Quantitative coronary angiography analysis was performed by a blinded core laboratory and patients grouped according to the results: obstructive CAD defined by the presence of at least one ≥ 50% stenosis, non-obstructive CAD as patients with a maximal stenosis in the 25-50% interval and non-CAD as no coronary lesions exceeding 25%. We excluded patients with potential confounders or incomplete data (n = 245). To avoid over-fitting the final cohort of 218 patients was randomly divided into to a training group for development (n = 127) and a validation group (n = 91). RESULTS: In both the training and the validation group the CAD-score was significantly increased in CAD patients compared to non-CAD patients (p < 0.0001). In the validation group the area under the receiver-operating curve was 77% (95% CI 63-91%). Sensitivity was 71% (95% CI 59-82%) and specificity 64% (95% CI 45-83%). CONCLUSION: The acoustic CAD-score is a new, inexpensive, non-invasive method to detect CAD, which may supplement clinical risk stratification and reduce the need for subsequent non-invasive and invasive testing.
Authors: M Becker; A B Roehl; U Siekmann; A Koch; M de la Fuente; R Roissant; K Radermacher; N Marx; M Hein Journal: Herz Date: 2013-06-23 Impact factor: 1.443
Authors: Victoria Delgado; Bogdan A Popescu; Sven Plein; Stephan Achenbach; Juhani Knuuti; Jeroen J Bax Journal: Eur Heart J Date: 2019-02-07 Impact factor: 29.983