Coronary flow reserve in patients with aortic stenosis and nonobstructed coronary arteries.
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 velocity reserve (CFVR). Recently, it has been shown that CFVR is an independent predictor for future cardiovascular events in AS patients. We investigated parameters representing left ventricular (LV) mass and wall thickness, diastolic dysfunction, LV workload and haemodynamic indexes of AS severity to determine which contributes the most to impaired CFVR in patients with AS and a nonobstructed coronary angiogram.


RESULTS
A total of 77 patients with moderate or severe AS, mean age 65.66 +/- 11.02 y (57.14% males), were enrolled in this prospective study. All patients had standard Doppler-echo study, coronary angiography and adenosine-stress transthoracic Doppler-echo for CFVR measurement. We took 2.5 as a cut-off value for impaired CFVR. Univariate analysis showed that aortic valve area (AVA), maximal velocity (Vmax), mean pressure gradient (Pmean), energy loss index (ELI), aortic valve resistance (AVR) and stroke work loss (SWL) were associated (P = 0.05) with impaired CFVR. Multivariate analysis showed that AVR was the best predictor of impaired CFVR (RR 0.900, Cl: 0.983-0.997, P = 0.007). Using ROC analysis, the AVR value of 211.22 dynes x s x cm(-5) had the highest accuracy in predicting the impaired CFVR (AUC-0.681, P=0.007, sensitivity 72%, specificity 52%, CI: 0.561-0.800).


CONCLUSIONS
Haemodynamic indices of AS severity, together with LV workload parameters, are the main determinants of CFVR. Among all parameters, AVR is the strongest predictor of CFVR in patients with moderate or severe AS and a nonobstructed coronary angiogram.
Department of Cardiology, University Clinical Centre of Serbia, Belgrade, Serbia. markobanovic71@gmail.com
Marko D
MD
Banovic
Bosiljka D
BD
Vujisic-Tesic
Vuk G
VG
Kujacic
Mark J
MJ
Callahan
Ivana P
IP
Nedeljkovic
Danijela D
DD
Trifunovic
Srdjan B
SB
Aleksandric
Milan Z
MZ
Petrovic
Slobodan D
SD
Obradovic
Miodrag C
MC
Ostojic
D000328:Adult; D000368:Aged; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001783:Blood Flow Velocity / Q000502:physiology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D012372:ROC Curve; D012039:Regional Blood Flow / Q000502:physiology; D014463:Ultrasonography