FATTY-ACID EXERCISE SCINTIGRAPHY AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

We performed a sequential fatty acid exercise-rest scintigraphy in 18 patients with an initially successful percutaneous transluminal corona ry angioplasty (PTCA) to study the concordance of trends in symptoms, exercise tolerance and myocardial metabolism. Eleven patients stopped the exercise because of angina pectoris in the preoperative test; 2 da ys after PTCA this number decreased to two, but again increased to eig ht 3 months later. Exercise time (9.7 +/- 0.6 min, mean +/- SEM) and m aximum exercise heart rate (128 +/- 4 beats min(-1)) were at least as good immediately after the operation as originally (8.8 +/- 0.6 min an d 121 +/- 4 beats min(-1), respectively). After 3 months both paramete rs were significantly (P<0.05) better (10.3 +/- 0.6 min and 136 +/- 4 beats min(-1), respectively) than originally. Some relative improvemen t in washout was noticed in 61% 2 days and in 56% of cases 3 months af ter PTCA. Fatty acid exercise uptake was more homogeneous in 72% of ca ses immediately after angioplasty and in 44% 3 months later. The trend in fatty acid uptake, exercise characteristics, and also in symptoms was most favourable among the eight patients with a dilatated left ant erior descending coronary artery. Although the gamma camera technique possibly underestimated the effects of angioplasty, the impaired fatty acid metabolism could be linked with persistent symptoms after the op eration. We conclude that most patients can safely participate in a sy mptom-limited (maximal) ergometry test already 2 days after PTCA, and that postoperatively myocardial perfusion and metabolism improve rapid ly. However, this advantage is eventually lost to some degree, even if exercise tolerance continues to improve.