title: Comparison of exercise testing and CMR measured myocardial perfusion reserve for predicting outcome in asymptomatic aortic stenosis: the PRognostic Importance of MIcrovascular Dysfunction in Aortic Stenosis (PRIMID AS) Study.
abstract: OBJECTIVE
  To assess cardiovascular magnetic resonance (CMR) measured myocardial perfusion reserve (MPR) and exercise testing in asymptomatic patients with moderate-severe AS.
  
  
  RESULTS
  Multi-centre, prospective, observational study, with blinded analysis of CMR data. Patients underwent adenosine stress CMR, symptom-limited exercise testing (ETT) and echocardiography and were followed up for 12-30 months. The primary outcome was a composite of: typical AS symptoms necessitating referral for AVR, cardiovascular death and major adverse cardiovascular events. 174 patients were recruited: mean age 66.2 ± 13.34 years, 76% male, peak velocity 3.86 ± 0.56 m/s and aortic valve area index 0.57 ± 0.14 cm2/m2. A primary outcome occurred in 47 (27%) patients over a median follow-up of 374 (IQR 351-498) days. The mean MPR in those with and without a primary outcome was 2.06 ± 0.65 and 2.34 ± 0.70 (P = 0.022), while the incidence of a symptom-limited ETT was 45.7% and 27.0% (P = 0.020), respectively. MPR showed moderate association with outcome area under curve (AUC) = 0.61 (0.52-0.71, P = 0.020), as did exercise testing (AUC = 0.59 (0.51-0.68, P = 0.027), with no significant difference between the two.
  
  
  CONCLUSIONS
  MPR was associated with symptom-onset in initially asymptomatic patients with AS, but with moderate accuracy and was not superior to symptom-limited exercise testing. ClinicalTrials.gov (NCT01658345).
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby road, Leicester, LE3 9QP, UK.
authors.forename: Anvesha
authors.initials: A
authors.lastname: Singh
authors.affiliation: Multidisciplinary Cardiovascular Research Centre & The Division of Cardiovascular and Diabetes Research, Leeds Institute of Genetics, Health & Therapeutics, Leeds University, Leeds, LS2 9JT, UK.
authors.forename: John P
authors.initials: JP
authors.lastname: Greenwood
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Berry
authors.affiliation: Cardiovascular Medicine Research Unit, School of Medicine and Dentistry, University of Aberdeen, Polwarth Building, Foresterhill, Aberdeen AB25 2ZD, UK.
authors.forename: Dana K
authors.initials: DK
authors.lastname: Dawson
authors.affiliation: Cardiology department, Kettering General Hospital Foundation Trust, Rothwell Rd, Kettering NN16 8UZ, UK.
authors.forename: Kai
authors.initials: K
authors.lastname: Hogrefe
authors.affiliation: Cardiology department, Royal Derby Hospital, Uttoxeter Rd, Derby DE22 3NE, UK.
authors.forename: Damian J
authors.initials: DJ
authors.lastname: Kelly
authors.affiliation: Cardiology department, University Hospital, Clifford Bridge Rd, Coventry CV2 2DX, UK.
authors.forename: Vijay
authors.initials: V
authors.lastname: Dhakshinamurthy
authors.affiliation: Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK.
authors.forename: Chim C
authors.initials: CC
authors.lastname: Lang
authors.affiliation: Cardiology department, Grantham and district hospital, 101 Manthorpe Rd, Grantham NG31 8DG, UK.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Khoo
authors.affiliation: Northampton General Hospital, Cliftonville, Northampton NN1 5BD, UK.
authors.forename: David
authors.initials: D
authors.lastname: Sprigings
authors.affiliation: Cardiovascular Medicine, Queen Elizabeth Hospital, Mindelsohn Way, Birmingham B15 2TH, UK.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Steeds
authors.affiliation: Brigham and Woman s Hospital and Harvard Medical School, 75 Francis St, Boston, Massachusetts 02115, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Jerosch-Herold
authors.affiliation: Department of Cardiovascular Sciences, University of Oxford, Level 6 West Wing, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK.
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.affiliation: Department of Cardiovascular Sciences, University of Oxford, Level 6 West Wing, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK.
authors.forename: Bernard
authors.initials: B
authors.lastname: Prendergast
authors.affiliation: Department of Cardiovascular Sciences, University College London, Gower St, Kings Cross, London WC1E 6BT, UK.
authors.forename: Bryan
authors.initials: B
authors.lastname: Williams
authors.affiliation: Roberston Centre for Bisotatistics, University of Glasgow, Level 11, Boyd Orr Building, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Ruiqi
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Cardiology department, Glenfield Hospital, Groby road, Leicester LE3 9QP, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Hudson
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby road, Leicester, LE3 9QP, UK.
authors.forename: Iain B
authors.initials: IB
authors.lastname: Squire
authors.affiliation: Roberston Centre for Bisotatistics, University of Glasgow, Level 11, Boyd Orr Building, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Ford
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby road, Leicester, LE3 9QP, UK.
authors.forename: Nilesh J
authors.initials: NJ
authors.lastname: Samani
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby road, Leicester, LE3 9QP, UK.
authors.forename: Gerry P
authors.initials: GP
authors.lastname: McCann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000503:physiopathology*; D019540:Area Under Curve; D003326:Coronary Circulation / Q000502:physiology*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D055815:Young Adult
keywords: Aortic stenosis; Exercise testing; Magnetic resonance imaging; Myocardial perfusion reserve