The accuracy of 1-day dual-isotope myocardial SPECT in a population with high prevalence of coronary artery disease.
BACKGROUND
In order to evaluate the diagnostic efficacy of the 1-day separate acquisition dual-isotope single-photon emission computed tomography (SPECT) protocol, using 201Tl for the rest and 99mTc-tetrofosmin for the stress images, a consecutive series of patients with suspected or known coronary artery disease (CAD) was studied that also underwent coronary angiography.


METHODS
The results of myocardial SPECT, using a semi-quantitative visual analysis, were acquired in 123 patients and compared with the results of coronary angiography. Sensitivity and specificity were calculated, using thresholds of > or = 50 and > or = 70% stenosis. As an alternative for specificity, the normalcy rate was determined in a separate group of 87 patients with a < 5% pre-test likelihood of CAD.


RESULTS
The prevalence of CAD using > or =50 and > or = 70% stenosis was 88 and 78%, respectively. The sensitivity for detection of patients with > or = 50 and > or = 70% stenosis was 94 and 97%, respectively while specificity was 62 and 59%, respectively. The high rate of false positive perfusion defects resulting in a low specificity could be explained by specific clinical issues. However, the routine assessment with additional clinical and electrocardiographic data resulted in a correct interpretation of most of the false positive perfusion defects. The positive predictive value was 92 and 85% and the negative predictive value 46 and 77%, using thresholds of > or = 50 and > or = 70% stenosis, respectively. The normalcy rate was 91%.


CONCLUSIONS
The one-day separate acquisition rest 201Tl/stress 99mTc-tetrofosmin SPECT protocol is an efficient procedure for myocardial perfusion scintigraphy with high sensitivity for detection of CAD. Specific clinical issues caused a low value for specificity. Therefore, clinical information and knowledge of the electrocardiogram is essential for a correct interpretation of SPECT images.
Groutars
Reginald G E J
RG
Department of Cardiology, University Hospital, Leiden, The Netherlands.
Verzijlbergen
J Fred
JF
Tiel-van Buul
Monique M C
MM
Zwinderman
Aeilco H
AH
Ascoop
Carl A P L
CA
van Hemel
Norbert M
NM
van der Wall
Ernst E
EE
D000241:Adenosine; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D009202:Cardiomyopathies / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D004452:Echocardiography; D005080:Exercise Test; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011237:Predictive Value of Tests; D015995:Prevalence; D019275:Radiopharmaceuticals; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; C078700:technetium tc-99m tetrofosmin; D000241:Adenosine