Determination of interobserver variability for identifying inducible left ventricular wall motion abnormalities during dobutamine stress magnetic resonance imaging.
OBJECTIVE
To determine the interobserver variability for identifying inducible left ventricular (LV) wall motion abnormalities during high-dose dobutamine/atropine stress cardiovascular magnetic resonance (DSMR).


RESULTS
Four readers from various institutions were supplied with the image data from 150 consecutive DSMR examinations and asked to grade wall motion and image quality throughout graded doses of dobutamine infusion administered to achieve 85% of the maximum age-predicted heart rate. Inducible ischaemia was identified if more than one segment demonstrated a new or worsening LV wall motion abnormality, and significant stenosis was defined as > or =50% luminal diameter reduction by quantitative contrast coronary angiography. Seventy-seven patients (51%) had luminal narrowings > or =50%. Diagnostic performance (sensitivity, specificity, diagnostic accuracy) of all readers was 78.2, 87.0 and 82.5%. Disagreement between two readers occurred in every seventh examination. Agreement on the presence or absence of inducible wall motion abnormalities was moderate (mean kappa value 0.59, range 0.52-0.76). Diagnostic performance and disagreement were independent of the presence of luminal narrowings > or =50% or the number of diseased coronary vessels. Image quality was regarded excellent in 89.3% of standard views.


CONCLUSIONS
In the setting of multiple observers from different institutions performing a diagnostic reading of DSMR examinations carried out at a single centre, the interobserver variability was low for identifying inducible LV wall motion abnormalities indicative of coronary arterial luminal narrowings > or =50%.
Paetsch
Ingo
I
Department of Cardiology, German Heart Institute Berlin, Germany. paetsch@dhzb.de
Jahnke
Cosima
C
Ferrari
Victor A
VA
Rademakers
Frank E
FE
Pellikka
Patricia A
PA
Hundley
W Gregory
WG
Poldermans
Don
D
Bax
Jeroen J
JJ
Wegscheider
Karl
K
Fleck
Eckart
E
Nagel
Eike
E
D002316:Cardiotonic Agents; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000503:physiopathology; D004280:Dobutamine; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods* / Q000592:standards; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000503:physiopathology
D002316:Cardiotonic Agents; D004280:Dobutamine