Severe thrombocytopenia induced by tirofiban after percutaneous coronary intervention: a case report.

BACKGROUND: Tirofiban is a nonpeptide glycoprotein IIb/IIIa receptor antagonist used widely in patients subjected to percutaneous coronary intervention. While the usage of tirofiban sets an important clinical benefit, severe thrombocytopenia can occur with use of this agent. CASE PRESENTATION: A 76-year-old Chinese man was admitted with 1-month history of sudden onset of chest tightness. He was diagnosed as having subacute inferior myocardial infarction, and percutaneous coronary intervention was performed. After the procedure, patient received tirofiban at 0.15 µg/kg/minute for 4 h. A blood sample was obtained for a complete blood count; severe thrombocytopenia was reported according to routine orders at our hospital. All antiplatelet drugs including tirofiban, aspirin, and clopidogrel were immediately discontinued. The patient received platelet transfusions and was treated with immunoglobulin G. Two days later, the patient's platelet count had increased to 75 × 109/L. There was a significant improvement after day 5, and the platelet count was 112 × 109/L. Seven days after the acute thrombocytopenia, he was discharged with normal platelet count. CONCLUSIONS: Clinicians should be particularly aware of tirofiban-induced thrombocytopenia in routine practice.

Increased stromal-cell-derived factor 1 enhances the homing of bone marrow derived mesenchymal stem cells in dilated cardiomyopathy in rats.

BACKGROUND: Stem cell transplantation has been shown to have beneficial effects on dilated cardiomyopathy. However, mechanism for stem cell homing to cardiac tissue in dilated cardiomyopathy has not yet been elucidated. METHODS: Mesenchymal stem cells were obtained from rat bone marrow, expanded in vitro, and labeled with (99m)Tc. Cardiomyopathy model was induced by doxorubicin in rats. (99m)Tc labeled cells were infused into the left ventricles in cardiomyopathy and control rats. Sixteen hours after injection, animals were sacrificed and different tissues were harvested to measure specific radioactivity. By use of real-time polymerase chain reaction and immunohistochemistry, mRNA and protein expressions for stromal-cell-derived factor 1 in cardiac tissue were measured. RESULTS: Labeling efficiency of mesenchymal stem cells was (70.0 ± 11.2)%. Sixteen hours after mesenchymal stem cell transplantation, the heart-to-muscle radioactivity ratio was increased significantly in cardiomyopathy hearts as compared to control hearts. Both mRNA and protein expressions of stromal-cell-derived factor 1 were up-regulated in cardiomyopathy hearts as compared with control hearts. CONCLUSION: In dilated cardiomyopathy induced by doxorubicin up-regulated expression of stromal-cell-derived factor 1 in heart may induce mesenchymal stem cells home to the heart.