Relationship of transient ischemic dilation in dipyridamole myocardial perfusion imaging and stress-induced changes of functional parameters evaluated by Tl-201 gated SPECT.
BACKGROUND
This study assessed whether transient ischemic dilation (TID) of the left ventricle is related to ischemic stunning, manifested by stress-induced decrease of left ventricular ejection fraction (LVEF) and worsening of wall motion, by use of dipyridamole-stress and redistribution thallium 201 gated single photon emission computed tomography (SPECT).


RESULTS
Ninety-two consecutive patients undergoing dipyridamole Tl-201 gated SPECT were included. Patients with a TID ratio in the highest quartile were defined as having TID. In patients with TID, end-diastolic volume (EDV) and end-systolic volume (ESV) were both significantly greater on dipyridamole-stress images than on redistribution images (P < .001). The degree of enlargement was much greater for ESV than EDV. In patients without TID, EDV and ESV were both decreased after stress (P < .001). Patients with TID had a lower mean LVEF on dipyridamole-stress images than on redistribution images (P < .001). Patients without TID had a higher mean LVEF on dipyridamole-stress images than on redistribution images (P < .001). Patients with TID had a significant worsening of global wall motion on dipyridamole-stress images than on redistribution images (P < .001), but patients without TID did not.


CONCLUSIONS
TID was significantly correlated with ischemic stunning, and the enlargement of ESV was an important factor resulting in TID.
Hung
Guang-Uei
GU
Department of Nuclear Medicine, Changhua Christian Hospital, Taiwan.
Lee
Kung-Wei
KW
Chen
Ching-Pei
CP
Lin
Wan-Yu
WY
Yang
Kuang-Tao
KT
D000368:Aged; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control; D004176:Dipyridamole; D005080:Exercise Test; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D017202:Myocardial Ischemia / Q000145:classification / Q000150:complications / Q000000981:diagnostic imaging; D017682:Myocardial Stunning / Q000150:complications / Q000000981:diagnostic imaging*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013223:Statistics as Topic; D013318:Stroke Volume; D013793:Thallium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014665:Vasodilator Agents; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology
D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; C027549:thallium chloride; D004176:Dipyridamole; D013793:Thallium