Effect of trimetazidine on Tc-99(m)-tetrofosmin uptake in patients with coronary artery disease

Myocardial uptake of Tc-99(m)-tetrofosmin in vivo is determined by a combin ation of flow and metabolic status of myocytes. The accumulation of tetrofo smin in the mitochondria is related to their ability to transduce metabolic energy into electronegative membrane potential. Trimetazidine (TMZ), an an tiischaemic drug, appears to have a metabolic cytoprotective effect related to mitochondrial function, since it does not induce systemic or coronary h aemodynamic changes. In this study, we evaluated the effects of TMZ on tetr ofosmin uptake in hypoperfused myocardial regions in patients with coronary artery disease (CAD). Twenty-two patients, 14 with previous myocardial inf arction (group A) and eight with a history of angina (group B), with angiog raphically documented CAD were studied. All patients underwent two tetrofos min SPET studies at rest, before (baseline) and 1 week after TMZ administra tion (post-TMZ). On quantitative analysis, 131 segments showed less tetrofo smin uptake at baseline. In these segments, tetrofosmin uptake was 51 +/- 1 3% at baseline and 55 +/- 15% post-TMZ (P < 0.001 vs control), in the 86 hy poperfused segments of group A, tetrofosmin uptake was 48 +/- 14% at baseli ne and 52 +/- 17% post-TMZ (P < 0.001 vs control). In the 45 hypoperfused s egments of group 8, tetrafosmin uptake was 56 +/- 9% at baseline and 60+/-1 0% post-TMZ (P < 0.001 vs control). In the remaining 309 segments, no signi ficant difference in tetrofosmin uptake before and after TMZ was observed. In conclusion, our results suggest that TMZ administration may increase myo cardial uptake of tetrofosmin in hypoperfused regions at rest in patients w ith CAD, based on its metabolic effect. ((C) 2000 Lippincott Williams & Wil kins).