Visualisation of cell death in vivo in patients with acute myocardial infarction

Background In-vivo visualisation and quantification of the extent and time- frame of cell death after acute myocardial infarction would be of great int erest. We studied in-vivo cell death in the hearts of patients with an acut e myocardial infarction using imaging with technetium-99m-labelled annexin- V-a protein that binds to cells undergoing annexin-V-a apoptosis. Methods Seven patients with an acute myocardial infarction and one control were studied. All patients were treated by percutaneous transluminal corona ry angioplasty (six primary and one rescue), resulting in thrombolysis in m yocardial infarction (TIMI) III flow of the infarct-related artery. 2 h aft er reperfusion, 1 mg annexin-V labelled with 584 MBq Tc-99m was injected in travenously. Early (mean 3.4 h) and late (mean 20.5 h) single-photon-emissi on computed tomo graphic (SPECT) images of the heart were obtained. Routine myocardial resting-perfusion imaging was also done to verify infarct local isation. Findings In six of the seven patients, increased uptake of Tc-99m-labelled annexin-V was seen in the infarct area of the heart on early and late SPECT images. No increased uptake was seen in the heart outside the infarct area . All patients with increased Tc99m-labelled annexin-V uptake in the infarc t area showed a matching perfusion defect, in a control individual, no incr eased uptake in the heart was seen. Interpretation Increased uptake of Tc-99m-labelled annexin-V is present in the infarct area of patients with an acute myocardial infarction, suggestin g that programmed cell death occurs in that area. The annexin-V imaging pro tocol might allow us to study the dynamics of reperfusion-induced cell deat h in the area at risk and may help to assess interventions that inhibit cel l death in patients with an acute myocardial infarction.