title: Prognostic value of coronary flow reserve in asymptomatic moderate or severe aortic stenosis with preserved ejection fraction and nonobstructed coronary arteries.
abstract: OBJECTIVE
  Patients with moderate and severe aortic stenosis (AS) and without obstructive epicardial coronary disease have been shown to have an impairment of coronary flow reserve (CFR). We investigated the prognostic significance of CFR in predicting death during mid-to-long-term follow-up in asymptomatic patients with moderate/severe AS, preserved ejection fraction (EF), and with nonobstructed coronary arteries.
  
  
  RESULTS
  A total of 127 patients with moderate or severe AS (effective orifice area of 1.5 cm(2) or less), mean age 66 ± 11 were enrolled in this prospective study. The median follow-up was 32 ± 7 months. All patients had standard Doppler echo study, coronary angiography, and adenosine-stress transthoracic Doppler echo for CFR measurement. Univariate analysis showed that diabetes mellitus, CFR, aortic valve area (AVA), maximal velocity (Vmax ), mean pressure gradient (Pmean ), energy loss index (ELI), aortic valve resistance (AVR), NT-proBNP, E/E', valvulo-arterial impedance (Zva ), and stroke work loss (SWL) were associated (P < 0.05) with death. Multivariable logistic regression analysis revealed that only Zva and CFR were independent predictors of death, with the CFR being the single strongest predictor (Table 2). Using receiver operating characteristics (ROC) analysis, the CFR value of 1.85 had the highest accuracy in predicting the death during mid-to-long-term follow-up (area under the curve; AUC 0.890, P = 0.009, sensitivity 96.3%, specificity 75%; 95% CI 0.287-0.946; Fig. 1). The Zva value of 5.52 Hg/mL per m had a sensitivity 70.0% and specificity 72.0% (AUC 0.766, 95% CI 0.587-0.946; P = 0.005).
  
  
  CONCLUSIONS
  This study demonstrates that CFR has a prognostic value in patients with asymptomatic moderate or severe AS with preserved EF and nonobstructed coronary arteries.
authors.affiliation: Department of Cardiology, University Clinical Center of Serbia, Belgrade, Serbia; Medical School, University of Belgrade, Belgrade, Serbia.
authors.forename: Marko
authors.initials: M
authors.lastname: Banovic
authors.forename: Vujisic-Tesic
authors.initials: VT
authors.lastname: Bosiljka
authors.forename: Brkovic
authors.initials: B
authors.lastname: Voin
authors.forename: Petrovic
authors.initials: P
authors.lastname: Milan
authors.forename: Nedeljkovic
authors.initials: N
authors.lastname: Ivana
authors.forename: Popovic
authors.initials: P
authors.lastname: Dejana
authors.forename: Trifunovic
authors.initials: T
authors.lastname: Danijela
authors.forename: Nikolic
authors.initials: N
authors.lastname: Serjan
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000503:physiopathology; D015331:Cohort Studies; D003326:Coronary Circulation / Q000502:physiology; D023921:Coronary Stenosis; D004452:Echocardiography / Q000379:methods; D018618:Echocardiography, Doppler, Color / Q000379:methods; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012372:ROC Curve; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology*; D015996:Survival Rate
keywords: aortic stenosis; coronary flow reserve; microcirculation; predictive value