The effect of oral anticoagulant therapy on aptt results from a bedside coagulation monitor

Objective. The Ciba Corning 512 coagulation monitor (CC512) can be used to monitor heparin therapy by performing an activated partial thromboplastin time (APTT) at the patient’s bedside. This study was designed to compare the CC512 results to results using the laboratory system. The relative sensitivities of both systems to the effect of oral anticoagulant therapy also was investigated.Methods. Activated partial thromboplastin times were performed with both the CC512 and laboratory system on 74 specimens from patients receiving IV heparin therapy, and on 14 specimens from patients on warfarin only. Heparin assays were performed on 43 of the specimens from the heparinized patients.Results. When a patient was receiving heparin only, the APTT results of the CC512 proved to be similar to existing laboratory methods. The CC512 APTT results of patients on warfarin only were markedly prolonged, whereas the laboratory APTTs were only slightly affected.Conclusion. The CC512 results were comparable to the laboratory system. However, the CC512 APTT was more sensitive to the effect of warfarin than the laboratory APTT system used in this study. CC512 APTT results on a patient receiving both oral and intravenous anticoagulation could be misleading. The authors wish to thank D.M. O’Brien and the nursing staff of the Coronary Care Unit for providing CC512 data and laboratory specimens, and I. Smith for the preparation of graphics. We also wish to thank Australian Diagnostics Corporation, which provided consumables.     

Chinese herbs and warfarin potentiation by 'Danshen'

Drug interactions with warfarin can be dangerous and although common drug interactions are now well recognized those with Chinese herbs are not widely appreciated. 'Danshen' is a herbal medicine often used for various complaints, particularly cardiovascular, in the Chinese community. We report a case of danshen-induced overcoagulation with severe and dangerous abnormalities of clotting in a patient with rheumatic heart disease.     

Breast fat necrosis secondary to warfarin-induced calciphylaxis,a rare mimicker of breast cancer: A case report and a review of literature

Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease.     

肇庆地区人群华法林相关基因CYP2C9*3和VKORC1的多态性分布研究及指导价值

目的 探讨广东省肇庆地区人群华法林相关基因细胞色素P450复合物亚基2C9（CYP2C9）和维生素K环氧还原酶复合物亚基1（VKORC1）多态性分布,并比较性别和中国西双版纳傣族、北京汉族、南方汉族间差异性的分布,为临床医生精准使用华法林进行抗凝治疗提供理论基础。方法 选取2019年5月-2022年1月于肇庆市第一人民医院进行华法林相关基因检测的患者122例,所有患者均采用数字荧光分子杂交技术对CY92C9^*3和VKORC1进行基因多态性检测,比较患者性别间和中国西双版纳傣族、北京地区汉族、南方地区汉族间的基因多态性分布情况,并对比基于药物基因组学指导下的华法林使用剂量与常规剂量使用华法林治疗后2~3 d后国际标准化比值（INR）达标率。结果 122例检测样本中,CY92C9^*3基因位点AA、AC、CC基因型所占的比例分别为95.90%、4.10%、0,C等位基因和T等位基因频率分别为97.95%和2.05%;VKORC1基因位点GG、GA、AA基因型分别为0.82%、19.67%、79.51%,A等位基因和C等位基因频率分别为10.66%和89.34%。不同性别间CY92C9^*3与VKORC1的基因型分布和等位基因分布差异均无统计学意义（P>0.05）。通过已有的数据库进行对比,肇庆地区的CY92C9^*3基因型、等位基因与1000 Genomes Project （1000 GP）西双版纳傣族、北京汉族与南方汉族对比无统计学差异（P>0.05）;但与1000 GP北京汉族对比,VKORC1的基因型和等位基因频率有统计学差异（P<0.05）;与1000GP西双版纳傣族对比,VKORC1的等位基因频率有统计学差异（P<0.05）;华法林在基因组学指导下的剂量与常规剂量治疗后INR达标率差异有统计学意义（P<0.01）。结论 肇庆地区人群存在CY92C9^*3和VKORC1基因多态性,其中VKORC1基因可能存在地域的差异,进行华法林相关基因检测可以为临床制定个体化华法林抗凝方案提供重要的参考价值。     

Fetal stroke and cerebrovascular disease: Advances in understanding from lenticulostriate and venous imaging,alloimmune thrombocytopaenia and monochorionic twins

Fetal stroke is an important cause of cerebral palsy but is difficult to diagnose unless imaging is undertaken in pregnancies at risk because of known maternal or fetal disorders. Fetal ultrasound or magnetic resonance imaging may show haemorrhage or ischaemic lesions including multicystic encephalomalacia and focal porencephaly. Serial imaging has shown the development of malformations including schizencephaly and polymicrogyra after ischaemic and haemorrhagic stroke. Recognised causes of haemorrhagic fetal stroke include alloimmune and autoimmune thrombocytopaenia, maternal and fetal clotting disorders and trauma but these are relatively rare. It is likely that a significant proportion of periventricular and intraventricular haemorrhages are of venous origin. Recent evidence highlights the importance of arterial endothelial dysfunction, rather than thrombocytopaenia, in the intraparenchymal haemorrhage of alloimmune thrombocytopaenia. In the context of placental anastomoses, monochorionic diamniotic twins are at risk of twin twin transfusion syndrome (TTTS), or partial forms including Twin Oligohydramnios Polyhydramnios Sequence (TOPS), differences in estimated weight (selective Intrauterine growth Retardation; sIUGR), or in fetal haemoglobin (Twin Anaemia Polycythaemia Sequence; TAPS). There is a very wide range of ischaemic and haemorrhagic injury in a focal as well as a global distribution. Acute twin twin transfusion may account for intraventricular haemorrhage in recipients and periventricular leukomalacia in donors but there are additional risk factors for focal embolism and cerebrovascular disease. The recipient has circulatory overload, with effects on systemic and pulmonary circulations which probably lead to systemic and pulmonary hypertension and even right ventricular outflow tract obstruction as well as the polycythaemia which is a risk factor for thrombosis and vasculopathy. The donor is hypovolaemic and has a reticulocytosis in response to the anaemia while maternal hypertension and diabetes may influence stroke risk. Understanding of the mechanisms, including the role of vasculopathy, in well studied conditions such as alloimmune thrombocytopaenia and monochorionic diamniotic twinning may lead to reduction of the burden of antenatally sustained cerebral palsy.     

华法林负荷量法抗凝治疗短暂性脑缺血发作的研究

目的 :观察华法林抗凝治疗短暂性脑缺血发作 (TIA)的安全性和疗效。方法 :2 0 0 3年 1月至2 0 0 4年 1月入院的TIA病人 ,适合抗凝治疗者 ,按Roberts依年龄调整华法林负荷量指南用药 ,对照组为 2 0 0 2年 1月至 2 0 0 3年 1月住院的TIA病人 ,并剔除用肝素治疗的病人。结果 :华法林组 10d内无脑卒中发生 ,仅有 4人次再次TIA ,未发现有出血者 ;对照组 10d内脑梗死 6例 ,再次TIA 12人次 ,华法林组于TIA发作后 10d内发生脑梗死及再次TIA较对照组低 (P <0 .0 5 )。结论 :按Roberts华法林负荷量指南抗凝治疗TIA优于非抗凝治疗 ,而且安全     

华法林对老年2型糖尿病合并心房颤动患者的效果观察

目的:观察华法林对老年2型糖尿病合并心房颤动(房颤)患者抗凝治疗的效果。方法:选择132例75岁以上2型糖尿病合并房颤患者,随机分为华法林中等强度组[国际标准化比值(INR)维持在2.1～2.5],华法林低等强度组(INR维持在1.5～2.0),对照组(口服阿司匹林),每组44例。随访1年,记录血栓栓塞和出血事件发生率。结果:华法林中等强度组、低等强度组和对照组血栓栓塞事件呈逐渐增多,对照组血栓栓塞发生率高于华法林中等和低等强度组(P<0.05),中等和低等强度组血栓栓塞发生率差异无统计学意义(P>0.05)。中等强度组、低等强度组和对照组出血事件呈逐渐减少,中等强度组出血发生率均高于低等强度组和对照组(P<0.05),但对照组出血发生率与低等强度组差异无统计学意义(P>0.05)。结论:华法林治疗老年2型糖尿病合并房颤患者,INR维持在1.5～2.0,不仅能够取得最佳的抗凝效果,同时能够有效地避免出血事件的发生。     

低强度抗凝合用洛伐他汀预防房颤患者脑卒中的研究

目的前瞻性研究低强度华法林抗凝合用洛伐他汀对非瓣膜性心房颤动患者脑卒中的预防作用。方法将自愿接受脑卒中预防的628例非瓣膜性心房颤动患者随机分为实验组和对照组各314例。对照组维持目标抗凝强度凝血活酶臣际标准化比率（INR）2．0～3．0;实验组维持目标抗凝强度INR1．5～1．9．并加用洛伐他汀20mg／d,随访7～56个月。结果与对照组比较,实验组出血事件和缺血性卒中的发生率明显降低．5a生存率明显提高。结论低强度华法林抗凝合用洛伐他汀能有效降低非瓣膜性心房颤动患者脑卒中发生率,降低华法林抗凝引起出血的危险性,提高长期生存率。