[Evaluation of treatment adaptation for low response to ASA in vascular surgery]. / Evaluation einer Therapieanpassung bei ASS-Low-Response in der Gefäßchirurgie.

BACKGROUND: A decreased antiplatelet prophylaxis (low response, LR/high on-treatment platelet reactivity, HPR) with acetylsalicylic acid (ASA) is associated with an increased risk of thromboembolic events. The prevalence of a LR is frequent with about 20% and a therapeutic regimen is not yet established. The aim of this prospective study was to evaluate the effectiveness of a therapeutic regimen for treatment adaptation when LR/HPR is detected in vascular surgery patients. METHODS: Overall, 36 patients under long-term antiplatelet treatment with 100 mg/day ASA and a detected ASA low response (ALR) were included in the study. In this patient group a modification of the prophylactic medication was carried out according to the established treatment plan and a control aggregometry was performed. The therapeutic regimen followed the test and treat principle. To evaluate the effect of ASA impedance, aggregometry with multiple electrodes was used (multiplate). RESULTS: All 36 patients were successfully transferred to response status with the treatment scheme. In 32 (88.89%) patients an increased dose of 300 mg/day ASA was carried out and in 2 (5.56%) patients the medication was changed from ASA to clopidogrel. A further 2 (5.56%) patients were switched to oral anticoagulation with phenprocoumon, due to other indications. Bleeding complications or other side effects did not occur. CONCLUSION: The chosen treatment regime for a low response proved to be effective and safe in vascular surgery patients. A guideline-compliant increase of the ASA dose from 100 mg to 300 mg/day predominantly led to an effective inhibition of platelet aggregation in the aggregometry.

[Pros and cons of classic crossectomy with stripping compared to endoluminal treatment : Competition or team play?] / Für und Wider der klassischen Krossektomie mit Stripping im Vergleich zu endoluminalen Therapieverfahren : Konkurrenzkampf oder Teamplay?

The chronic venous insufficiency (CVI) of the leg veins is one of the most common diseases in our society. Thus, it is important to know the clinical picture of CVI and the pros and cons of the different treatment options. Of the various treatments available for varicose veins (conservative therapy, operative procedures, endoluminal techniques, foam sclerotherapy), an evidence-based, treatment option should be individually chosen for each patient. In this article, the pros and cons of surgery are compared with endoluminal therapy in order to draw practical conclusions for the treatment decision.

[Prevalence of acetylsalicylic acid (ASA) - low response in vascular surgery]. / Prävalenz der ASS-Low-Response in der Gefäßchirurgie.

BACKGROUND: Research has revealed that a decreased antiplatelet effect (low response [LR]/high on-treatment platelet reactivity [HPR]) of acetylsalicylic acid (ASA) and clopidogrel is associated with an increased risk of thromboembolic events. There are extensive ASA low response (ALR) and clopidogrel low response (CLR) prevalence data in the literature, but there are only a few studies concerning vascular surgical patients. The aim of this study was to examine the prevalence and risk factors of ALR and CLR in vascular surgical patients. MATERIALS AND METHODS: We examined n = 154 patients with an antiplatelet long-term therapy, who were treated due to peripheral artery occlusive disease (PAD) and/or arteria carotis interna stenosis (CVD). To detect an ALR or CLR, we examined full blood probes with impedance aggregometry (ChronoLog® Aggregometer model 590). Risk factors were examined by acquisition of concomitant disease, severity of vascular disease, laboratory test results and medication. RESULTS: We found a prevalence of 19.3 % in the ALR group and of 21.1 % in the CLR group. Risk factors for ALR were an increased platelet and leucocyte count and co-medication with pantoprazole. We found no significant risk factors for a decreased antiplatelet effect of clopidogrel treatment. CONCLUSION: The investigated prevalence for ALR and CLR are in the range of other studies, particularly based on cardiological patients. More investigations are needed to gain a better evaluation of the risk factors for HPR and to develop an effective antiplatelet therapy regime to prevent cardiovascular complications.

Functional regions of the human cytomegalovirus protein pUL97 involved in nuclear localization and phosphorylation of ganciclovir and pUL97 itself.

In order to identify functional regions of the human cytomegalovirus protein pUL97 (i) different 5' fragments of the UL97 open reading frame (ORF) were fused to the coding region of the green fluorescent protein and (ii) recombinant vaccinia viruses (rVV) were generated carrying two full-length and 11 mutated UL97 ORFs. The results indicated the presence of an N-terminal region within pUL97 which changed the intracellular distribution of the fusion proteins. pUL97 was localized in the nucleus, but not in the nucleoli, and was detected in the nuclear matrix fraction. Expression of all pUL97 mutants could be confirmed by Western blot analysis. pUL97-associated ganciclovir (GCV) phosphorylation in rVV-infected cells, determined quantitatively by HPLC analysis, was abolished completely using individual UL97 deletion mutants. Phosphorylation of full-length and some of the mutated pUL97 was detected in cells infected with the rVVs. The UL97 constructs carrying point mutations from GCV-resistant HCMV isolates at positions 460M, 520H, 594V, and the 4 aa deletion 590AACR593, also resulted in decreased but not abolished phosphorylation of GCV in the rVV system, whereas the phosphorylation of pUL97 itself was not influenced. The rVV system is a suitable method for quantitatively testing the functional relevance of pUL97 mutations.