[Head to head comparison of dobutamine alone and combined with nitrate stress echocardiography and 99mTc-MIBI/18FDG myocardial SPECT image for diagnosis of viable myocardium in patients with severe left ventricular dysfunction].
OBJECTIVE
This study was sought to compare the sensitivity, specificity and accuracy of (1) dual isotope simultaneous acquisition single-photon emission computed tomography (DISA SPECT) myocardial image with (99m)Tc-sestamibi/(18)F-fluorodeoxyglucose ((99m)Tc-MIBI/(18)FDG); (2) low dose dobutamine alone and combined with Isosorbide Dinitrate (ISDN: Isoket) stress two dimensional echocardiography (2DE) to predict regional movement recovery after revascularization (CRV) in patients with old myocardial infarction (OMI) and severe left ventricular dysfunction.


METHODS
Twenty-six patients (mean age 51 +/- 8 years, male 25, female 1) with OMI and severe left ventricular dysfunction (mean left ventricular ejection fraction, LVEF (38.6% +/- 4.9%) underwent low dose dobutamine 10 microg x kg(-1) x min(-1) (Dob10 microg) and ISDN (286 +/- 31 microg/min) combined with Dob5 microg (ISDN-Dob 5 microg) 2DE and DISA SPECT within one week. In echocardiogram and DISA SPECT images: the left ventricle (LV) was divided into 16 segments. The semi-quantitative scoring system was used for both images. Myocardial viability was defined as an improvement of at least >or= 1 grade in at least two contiguous segments at rest 2DE after CRV. The viable segments detecting rate with stress 2DE and DISA SPECT were compared. Compared with the results of post-CRV, the sensitivity, specificity and accuracy of detecting viable segments of two methods were calculated.


RESULTS
Among 272 abnormal segments in 26 patients, 156 (57.4%) segments showed contractile improvement after CRV. The viable segments detecting rate with DISA SPECT was 72.4% (134/254), which was significantly higher than the contractile improved rate after CRV (P < 0.001). During Dob10 microg 2DE and ISDN-Dob5 microg 2DE, the detecting rates were 65.5% (163/249) and 65.7% (176/268), respectively, which were both comparable to the improved rate after CRV (both P > 0.05). With DISA SPECT, the sensitivity, specificity and accuracy were 93.7%, 55% and 76.8%, respectively. Compared with DISA SPECT, Dob10 microg 2DE showed similar sensitivity (88.6%), specificity (64.2%) and the accuracy (77.9%). When ISDN combined with Dob5 microg, the sensitivity (91.4%), specificity (68.1%) and accuracy (81.4%)were comparable to those of Dob10 microg 2DE and DISA SPECT (all P > 0.05), while the specificity was even higher than DISA SPECT (P < 0.05).


CONCLUSIONS
In identifying myocardial viability in patients with OMI and severe left ventricular dysfunction, DISA SPECT has higher sensitivity, lower specificity and better accuracy. Dob10 microg and ISDN-Dob5 microg 2DE are both equivalent to DISA SPECT in sensitivities, specificities and accuracies, and even higher in specificity in ISDN-Dob5 microg 2DE.
Yang
Yue-jin
YJ
Division of Coronary Heart Disease, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China. yyj@public.bta.net.cn
Yang
Wei-xian
WX
Shi
Rong-fang
RF
Hu
Feng-huan
FH
You
Shi-jie
SJ
Tian
Yue-qin
YQ
He
Zuo-xiang
ZX
Wang
Yan-wu
YW
Ye
Ling
L
Chen
Ji-lin
JL
Gao
Run-lin
RL
Chen
Zai-jia
ZJ
D000328:Adult; D004280:Dobutamine; D004452:Echocardiography / Q000379:methods*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007548:Isosorbide Dinitrate; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D009206:Myocardium; D032383:Myocytes, Cardiac / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D019788:Fluorodeoxyglucose F18; D004280:Dobutamine; D007548:Isosorbide Dinitrate