Thallium-201 single-photon emission computed tomography: quantitative assessment of left ventricular perfusion and structural change in patients with chronic aortic regurgitation.
BACKGROUND
Previously, perfusion defect in the left ventricle was detected by thallium-201 (201T1) single-photon emission computed tomography (SPECT) in aortic regurgitation (AR). The significance of 201T1 SPECT, however, has not been clarified. Limited information is available regarding the relationship between functional characteristics and scintigraphic findings.


OBJECTIVE
The purpose of this study was to elucidate the role of exercise 201T1 SPECT in assessing myocardial perfusion or structural change in chronic AR. We examined the correlation between 201T1 scintigraphic findings and left ventricular (LV) function parameters in 11 patients.


METHODS
Defect volume ratio (DVR) in exercise 201T1 SPECT was used as a parameter of the range of abnormal thallium distribution. Left ventricular parameters were obtained by right and retrograde left cardiac catheterizations. The relationship between DVR and the parameters was analyzed.


RESULTS
The DVR ranged from 1.0 to 28.3% (average 12.1 + 8.5 %). There was a significant correlation (r = 0.77, p < 0.05) between DVR and end-diastolic volume index (EDVI), a definite correlation (r = 0.66, p < 0.01) between DVR and end-systolic volume index (ESVI), and a good correlation (r = -0.77, p <0.05) between DVR and end-systolic wall stress (ESS)/ ESVI; however, no such correlation was found between DVR and ejection fraction.


CONCLUSIONS
All patients showed abnormal defects in 201T1 accumulation scattered across the entire ventricle. A strong correlation between DVR and ESS/ESVI, an index of myocardial contractility, was a major finding of this study, suggesting a significant association between abnormal myocardial perfusion or structural alteration and reduction in myocardial contractility in chronic AR.
Yasuda
Harumasa
H
Division of Cardiovascular Surgery, Department of Surgery, Osaka University Graduate School of Medicine, Osaka, Japan. hyasjj@ybb.ne.jp
Taniguchi
Kazuhiro
K
Takahashi
Toshiki
T
Sawa
Yoshiki
Y
Matuda
Hikaru
H
D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D006328:Cardiac Catheterization; D002908:Chronic Disease; D003937:Diagnosis, Differential; D005080:Exercise Test; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013793:Thallium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D013793:Thallium