ABSTRACT
INTRODUCTION: Carotid artery stenting has become a possible treatment of significant carotid stenosis. The risk of stent occlusion and restenosis might be increased by abnormal rheological conditions amplified platelet aggregation and free radical production during the operation. AIMS: The aim of this study was to assess the changes of the rheologic parameters, platelet aggregation, and oxidative stress after endovascular treatment of carotid stenosis. METHODS: 18 patients (11 men, ages 68 +/- 9 years and 7 women, ages 62 +/- 8 years) suffering from significant carotid stenosis and treated with carotid endovascular intervention were examined. Alteration in hemorrheological parameters as well as epinephrine-, ADP-, and collagen-induced platelet aggregation were evaluated. Oxidative stress was characterized by the determination of catalase activity. The measurements were carried out directly before and after the procedure and 1, 2, 5 days and 1 month following the intervention. Preceding the operation the patients were administered a maximum dose (300 mg) of clopidogrel. RESULTS: The hematocrit, the plasma fibrinogen concentration (Pfc) and whole blood-, and plasma viscosity (Wbv and Pv) decreased significantly immediately after stenting ( p < 0.001). By the fifth day following the intervention the Pfc, Wdv, Pv, red blood cell (Rbc) aggregation and ADP-induced platelet aggregation increased significantly ( p < 0.0001) compared to values measured after the procedure. At 1 month follow-up these parameters, excepting Wbv, decreased significantly compared to measurements made on the 5th day. On the other hand, catalase activity showed significant elevation by the end of the first month. CONCLUSION: Hemorrheological parameters and platelet aggregation showed specific changes following carotid stenting. Abnormal changes of the rheological conditions and increasing platelet activation are the most pronounced in the first week following stenting, which may lead to the stent's early occlusion. Oxidative stress production returned to baseline levels only by the end of the first month.
Subject(s)
Carotid Stenosis/physiopathology , Carotid Stenosis/surgery , Free Radicals/metabolism , Hemorheology , Platelet Activation , Stents , Aged , Carotid Stenosis/metabolism , Clopidogrel , Female , Fibrinogen/metabolism , Follow-Up Studies , Hematocrit , Humans , Male , Middle Aged , Oxidative Stress , Platelet Aggregation , Platelet Aggregation Inhibitors/therapeutic use , Recurrence , Risk Factors , Ticlopidine/analogs & derivatives , Ticlopidine/therapeutic use , Time FactorsABSTRACT
INTRODUCTION: It shows the importance of cerebrovascular diseases that they are the third main cause of death exceeded only by coronary artery diseases and cancer. Cerebral ischemia leads to irreversible brain damage, thereby it is important to rescue the hypoperfused areas. Patients without stroke but with chronic cerebral hypoperfusion can also benefit from the increasing of the cerebral blood flow. METHODS: The aim of this review was to summarize the indications and the potential effects of vinpocetine in acute and chronic cerebrovascular diseases based on clinical studies. RESULTS: There is no evidence that vinpocetine treatment is applicable in acute ischemic stroke, only few study with low patient number showed a slight but significant improvement in the patients conditions. In chronic cerebrovascular patients after single dose and long-term vinpocetine therapy, PET, TCD, SPECT and NIRS examinations showed increasing perfusion and elevated glucose and O 2 consumption of the examined areas, furthermore significant improvement of the rheologic factors was detected. A meta-analysis of international clinical studies showed a significant improvement in cognitive achievement in chronic stroke patients after oral therapy. CONCLUSION: The cited studies showed the potential multi-pharmacological effects of vinpocetine and its beneficial hemorheological potential. The drug also improves the blood flow and the metabolism of the affected brain areas. There is increasing evidence that vinpocetine improves the quality of life in chronic cerebrovascular patients.
