The validation of fractional flow reserve in patients with coronary multivessel disease: a comparison with SPECT and contrast-enhanced dobutamine stress echocardiography.
Fractional flow reserve (FFR) is a new but well established parameter for the hemodynamic evaluation of coronary stenoses. A FFR below 0.75 was validated as functionally significant in coronary one or two vessel disease. This study was designed to prospectively define the best FFR cut off value (BCV) in patients with multivessel disease using two noninvasive tests, myocardial perfusion scintigraphy (SPECT) and contrast-enhanced dobutamine stress echocardiography (DSE) as reference methods.


METHODS
47 symptomatic patients (29 male, mean age 64+/-10 yrs) with angiographically intermediate coronary lesions (50-75% diameter stenosis) entered the study. DSE (5-40 microg/min/kg dobutamine) was performed after intravenous injection of a second generation transpulmonary contrast agent. SPECT (Tc-99m-MIBI) was done at peak stress. All tests (DSE, SPECT and FFR) were performed within 4 weeks.


RESULTS
SPECT yielded positive results in 15 and DSE in 16 patients, respectively. Mean FFR measured in the target lesion (RCA n=10; LAD n=22, RCX n=15) was 0.80+/-0.13. FFR was <0.75 in 15 patients. By performing a ROC analysis the BCV (highest sum of sensitivity and specificity) was found at 0.75. At this cut off value using both non-invasive tests as reference method, sensitivity and specificity were 83 and 77%.


CONCLUSIONS
In patients with multivessel disease, a FFR <0.75 identifies a hemodynamically relevant lesion as compared to DSE and SPECT. This study underlines that FFR criteria are also applicable in patients with complex coronary artery disease.
Erhard
I
I
Dept. of Cardiology, Medizinische Poliklinik-Innenstadt, University of Munich, Ziemssenstr. 1, 80336 Munich, Germany. Klauss@med.uni-muenchen.de
Rieber
J
J
Jung
P
P
Hacker
M
M
Schiele
T
T
Stempfle
H-U
HU
König
A
A
Baylacher
M
M
Theisen
K
K
Siebert
U
U
Klauss
V
V
D000368:Aged; D000418:Albumins; D001794:Blood Pressure / Q000502:physiology; D002637:Chest Pain / Q000000981:diagnostic imaging / Q000209:etiology; D003287:Contrast Media / Q000008:administration & dosage; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D025401:Echocardiography, Stress; D005260:Female; D005466:Fluorocarbons; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology; D011379:Prognosis; D011446:Prospective Studies; D012016:Reference Values; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon
D000418:Albumins; D003287:Contrast Media; C099458:FS 069; D005466:Fluorocarbons