New wearable cardiac acoustic monitoring technology for evaluation of subclinical leaflet thrombosis after transcatheter aortic valve replacement

Background Subclinical leaflet thrombosis (SLT) is a common complication after transcatheter aortic valve replacement (TAVR). Multidimensional CT (MDCT) is the main imaging mortality for the diagnosis of SLT but it enhances the risk of contrast-induced nephropathy. Our study aimed to use an innovative wearable acoustic cardiography (ACG) device to diagnose SLT as an alternative option. Methods This prospective cohort study consecutively enrolled patients with severe symptomatic aortic stenosis who underwent successful TAVR. We collected and analysed clinical data including ACG measurements and imaging results. Discrimination capability analysis (ie, area under the curve (AUC), sensitivity, specificity) of a composite feature from ACG readings in predicting SLT during follow-up was performed. Based on the severity of SLT, patients were categorised into three groups: Group 1 (no SLT), Group 2 (mild SLT) and Group 3 (moderate-to-severe SLT). Results 116 patients consented and enrolled in the stud y . At the 1-month follow-up, MDCT revealed a 25% prevalence of SLT with 11.2% classified as moderate-to-severe. ACG analysis revealed distinctive patterns of early systolic, baseless and high-energy murmurs exclusively in patients in Group 3 but not in group 2. The diagnostic performance of ACG for moderate-to-severe SLT showed a sensitivity of 84.62%, specificity of 91.26% and AUC of 0.920 (95% CI: 0.855 to 0.962, p<0.001). At 6 months, both MDCT and ACG indicated that nine (70%) patients in Group 3 who received anticoagulant therapy achieved complete resolution of SLT. Conclusion ACG can be considered as an effective tool to assist in the diagnosis of SLT based on deterioration of transvalvular haemodynamics post-TAVR. Further studies are required to confirm its utility as a valuable non-invasive diagnostic and monitoring tool. Trial registration number ChiCTR2300072300.