ISSN:
1619-7089
Keywords:
Coronary bypass surgery
;
Thallium-201 reinjection
;
Myocardial viability
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Twenty-two patients with single-vessel left anterior descending coronary artery disease were investigated by means of dipyridamole stress thallium-201 myocardial perfusion scintigraphy, using single photon emission tomography (SPET), 1 week before and 2–5 weeks after coronary bypass surgery. The dose of dipyridamole was 0.56 mg/kg, and the injected activity of 201T1 was 74 MBq. Before surgery, and after completion of the redistribution study, a further 37 MBq of 201T1 was injected. Ten minutes and 1 h later, repeated SPET imaging were performed. SPET images were evaluated both subjectively and semiquantitatively, using a five-grade segmental defect score system, with higher scores for more severe perfusion defects. Before surgery, the 3-h redistribution images revealed complete or partial persistence of the perfusion defects in all patients. On the images taken 10 min after reinjection, these defects were completely filled in four cases, and partially filled in ten cases. Further positive changes were observed on the 1-h post-reinjection images in four cases. Three of the 1-h post-reinjection images exhibited a paradox redistribution. The stress images after surgery corresponded well to the 201T1 distribution on the preoperative 1-h post-reinjection images in 11 cases. The average of the segmental defect severity scores was 17.0 after stress, 10.1 at rest, 7.1 10 min after reinjection and 6.4 1 h after reinjection. After surgery, the average of both the post-stress and the 3-h redistribution scores was 3.1. The correlation coefficients between the segmental scores of the postoperative resting study and the preoperative 3-h resting and the 10-min and 1-h post-reinjection studies were 0.72, 0.69 and 0.78, respectively. It is concluded that post-reinjection 201T1 images before surgery are good predictors of myocardial perfusion after revascularization. The best results are obtained if imaging is performed 1 h after reinjection.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00170001
Permalink
