[The potential significance of early effort myocardial scintigraphy following PTCA]

Exercise 201Tl scintigraphy before and after successful PTCA was evaluated in 69 patients with coronary stenosis > 60%. Mean luminal stenosis was found reduced from 74 +/- 10% to 31 +/- 11% (58% reduction). Scintitomographic examination within 3 weeks following intervention showed a reduction of the exercise perfusion defect from 17.00 +/- 14.6 to 5.8 +/- 7.8 arbitrary units (66% reduction). Angiographically, re-stenosis was identified in 22/41 patients (54%) after 6 months. Unexpectedly, re-stenosis could not be predicted by early 201Tl scintigraphy (positive and negative predictive value in patients with single-vessel disease: 61% and 41%, resp.). Nevertheless, evaluation of PTCA results was possible (sensitivity 83%). However, postinterventional transient defects, indicating ischemia, were often seen (all patients: 43/69; patients with single-vessel disease: 31/55) and not indicative of failure of the intervention. Thus, post-PTCA scintigrams should be compared with scintigrams recorded before the intervention to ensure reliable follow-up control.