Clin Res Cardiol 107, Suppl 3, October 2018

Droplet digital PCR for quantification of miR-21, miR-208a and miR-499 in patients with coronary artery disease

L. Benning1, J. E. Walter2, M. Follo3, R. M. Mayr2, S. E. Robinson4, U. Honegger2, D. Stallmann1, R. Twerenbold2, P. Badertscher2, J. Du Fay de Lavallaz2, D. Dürschmied1, C. Puelacher2, C. Bode1, I. Ahrens5, C. Müller2, M. Hortmann1

1Abteilung für Kardiologie und Angiologie I, Herzzentrum Bad Krozingen, Freiburg im Breisgau; 2Abt. für Kardiologie, Universitätsspital Basel, Basel, CH; 3Zentrum für Translationale Zellforschung (ZTZ), Core Facility - Universitätsklinikum Freiburg, Freiburg; 4Baker Heart and Diabetes Institute, Melbourne Victoria, AU; 5Innere Med. - Klinik für Kardiologie, Krankenhaus der Augustinerinnen, Akademisches Lehrkrankenhaus, Köln;

Introduction Circulating microRNAs (miRNAs) have shown potential as new biomarkers for myocardial ischemia. Recently, droplet digital polymerase chain reaction (ddPCR) has been introduced as a method for absolute quantification that exhibits superior technical qualities in quantifying circulating miRNAs. Methods In this study, droplet digital PCR was used to quantify serum miRNA levels in patients with functionally relevant coronary artery disease (CAD). We obtained blood samples for measurement of high-sensitivity troponin I (hs-cTnI) and for miRNA quantification before, immediately after peak stress and 2 hours after stress testing in a blinded manner in consecutive patients admitted for rest/stress myocardial perfusion single-photon emission tomography/computed tomography (MPI-SPECT/CT). Serum concentrations of miR-21, miR-208a and miR-499 were quantified with the help of ddPCR to assess the potential of these miRNAs as valid biomarkers for myocardial injury or ischemia. Expert interpretation of MPI-SPECT/CT, coronary angiography and fractional flow reserve, if performed, was used to identify functional relevant CAD. Results Functionally relevant CAD was detected in 85 patients of the total 200 patients who were included in this study (42%). When comparing patients with functionally relevant CAD to those without functionally relevant CAD, neither the concentrations of miR-21, miR-208a, nor miR-499 differed significantly at rest, stress, or 2 hours after stress testing while hs-cTnI concentrations were significantly increased in patients with functionally relevant CAD (p<0.001). Changes in miRNA or hs-cTnI concentrations induced by exercise have not shown any relevant diagnostic utility and were similar in patients with and without functionally relevant CAD. Conclusion This pilot study shows that concentrations of miR-21, miR-208a and miR-499 at rest, after exercise and 2 hours after stress testing do not provide any additional value in diagnosing functionally relevant CAD.

http://www.abstractserver.de/dgk2018/ht/abstracts//BS239.htm