Diagnostic accuracy of combined intracoronary pressure and flow velocity information during baseline conditions: adenosine-free assessment of functional coronary lesion severity.
BACKGROUND
The assessment of functional coronary lesion severity using intracoronary physiological parameters such as coronary flow velocity reserve and the more widely used fractional flow reserve relies critically on the establishment of maximal hyperemia. We evaluated the diagnostic accuracy of the stenosis resistance index during nonhyperemic conditions, baseline stenosis resistance index, compared with established hyperemic intracoronary hemodynamic parameters, because achievement of hyperemia can be cumbersome in daily clinical practice.


RESULTS
A total of 232 patients, including 299 lesions (mean stenosis diameter 55%±11%), underwent myocardial perfusion scintigraphy for documentation of reversible perfusion defects. Distal coronary pressure and flow velocity were assessed with sensor-equipped guidewires during baseline and maximal hyperemia, induced by an intracoronary bolus of adenosine (20-40 µg). We determined stenosis resistance (SR) during baseline and hyperemic conditions as well as fractional flow reserve and coronary flow velocity reserve. The discriminative value for myocardial ischemia on myocardial perfusion scintigraphy of all parameters was compared using receiver-operating-characteristic curves. Baseline SR showed good agreement with myocardial perfusion scintigraphy. The diagnostic performance of baseline SR (area under the curve, 0.77; 95% CI, 0.71-0.83) was as accurate as fractional flow reserve and coronary flow velocity reserve (area under the curve, 0.77; 95% CI, 0.71-0.83 and area under the curve, 0.75; 95% CI, 0.68-0.81 respectively; P>0.05 compared with baseline SR for both). However, hyperemic SR, combining both pressure and flow velocity information during hyperemia, was superior to all other parameters (area under the curve, 0.81; 95% CI, 0.76-0.87; P<0.05 compared with all other parameters).


CONCLUSIONS
Combined pressure and flow velocity measurements during baseline conditions may provide a useful tool for functional lesion severity assessment without the need for potent vasodilators.
Department of Cardiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
Tim P
TP
van de Hoef
Froukje
F
Nolte
Peter
P
Damman
Ronak
R
Delewi
Matthijs
M
Bax
Steven A J
SA
Chamuleau
Michiel
M
Voskuil
Maria
M
Siebes
Jan G P
JG
Tijssen
Jos A E
JA
Spaan
Jan J
JJ
Piek
Martijn
M
Meuwissen
D000241:Adenosine; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D006328:Cardiac Catheterization / Q000379:methods / Q000592:standards; D003326:Coronary Circulation / Q000502:physiology*; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods / Q000592:standards*; D012372:ROC Curve; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D017256:Technetium Tc 99m Sestamibi; D014665:Vasodilator Agents
D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; D017256:Technetium Tc 99m Sestamibi; D000241:Adenosine