99mTc-MIBI myocardial perfusion tomography for prediction and confirmation of restenosis after PTCA

The predictive value of stress 99mTc-MIBI imaging for restenosis and recurrent chest pain is still not well enough clarified. Literature data on 201Tl so far published point to better sensitivity and specificity of tomographic imaging, as compared to ECG-exercise test. Thirty patients (20 after recanalization for chronic occlusions, and 10 after balloon angioplasty) undergo 99mTc-MIBI tomography 1 to 1.5 months after PTCA. Eleven of them are mildly symptomatic, with negative or non diagnostic ECG exercise test. Reversible perfusion defect in the territory of dilated vessel is interpreted as a positive tomographic criterion for restenosis. Positive criterion is found in five of symptomatic patients, and in four asymptomatic ones. Control angiography is performed in 9 patients with positive criterion from tomography, and six symptomatic although with negative perfusion criterion. restenosis is documented in 6/9 patients with positive tomography, one with stenosis distal to angioplasty, and two - false-positive. In none of the patients with negative perfusion criterion is restenosis noted. The inference is reached that stress 99mTc-MIBI tomography and 201Tl as well may be used for prediction and confirmation of restenosis after PTCA. (authors)