机械心脏瓣膜置换术后远期抗凝状态临床观察及意义

目的:机械心脏瓣膜置换术后远期INR与并发症的关系,最佳抗凝强度范围及意义。方法:对机械心脏瓣膜置换术后出院半年以上的患者在门诊检查四项凝血指标(PT,PTR,INR,Fbg,APTT)224例次,按照INR结果不同分为三组:I组INR<1.5,II组INR1.5～2.5,III组INR>2.5。结果:I组26例/次,华发林服用量3.55±1.03mg,INR1.39±0.10,出现脑栓4例/次,并发症15.3%;II组176例/次,华发林服用量3.44±1.02mg,INR2.13±0.11,出现鼻出血、血尿5例/次,并发症2.8%;III组22例/次,华发林服用量2.96±1.07,INR2.91±0.62,出现鼻出血、皮下出血4例/次,并发症18%。结论:II组的例/次占总数的77.8%,INR在1.5～2.5之间并发症最低,说明INR在1.5～2.5之间是安全可靠的,是本地区最佳抗凝强度范围。机械心脏瓣膜置换术后抗凝强度是动态的,术后远期更应高度关注抗凝状态。

血浆D-二聚体在机械心脏瓣膜置换术后不同抗凝强度中的表达及临床意义

目的:了解D-二聚体检查在心脏瓣膜置换术后抗凝治疗中的地位和意义。方法:对行机械心脏瓣膜置换术后出院在2月以上的患者在门诊检查凝血四项(INR、Fbg、APTT、TT)及D-二聚体262例次,按照INR不同分为三组(I组:INR<1.5;II组:INR1.5～2.5;III组:INR>2.5),分析。结果:各组都有D-二聚体阳性的病例,但是发现大多数检验单集中在I及II组。在I组里的D-二聚体阳性和血栓发生率明显高于II组。I组和III组比较差异无统计学意义。II组和III组比较差异无统计学意义。在I组里出现2例脑栓塞和两例下肢血管栓塞患者;II组无栓塞患者;III组1例患者是在当地抗凝不足导致左下肢血管栓塞,加强抗凝及抗血栓治疗后,按INR的改变分到III组的。结论:D-二聚体在心脏瓣膜置换术后抗凝状态检查中占有很重要的地位,应该在心脏外科医生当中引起重视,特别是在前一次INR<1.5的患者中,应同时检查。在没有检查D-二聚体的情况下发现INR<1.5后应补充检查,以防止血栓的发生。

Anticoagulation therapy in intra-aortic balloon counterpulsation： Does IABP really need anti-coagulation ？

Objective: To investigate if intra-aortic balloon pump(IABP) is contraindicated without anticoag-ulation therapy. Methods: Some 153 IABP patients in the King Abdulaziz Cardiac Center(KSA) were random-ly assigned into two groups. Anticoagulation group( Group A) consisted of 71 patients who were given heparin intravenously with target aPTT 50 - 70 seconds. Non-anticoagulation group( Group B) consisted of 82 patients without intravenous heparin during balloon pumping. Hematological parameters including platelet count, D-dimer, Plasminogen activator inhibitor-1 (PAI-1) and fibrinogen degradation products(FDP) were checked respectively at the point of baseline, 24 hours, 48 hours and 24 hours post IABP counterpulsation. Clot deposits on balloon surface, vascular complications from IABP including bleeding and limb ischemia were recorded.Results: Platelet count and PAI-1 level decreased at 24 hours and 48 hours in both groups ( P < 0.05) . D-dimer and FDP level increased at 24 hours and 48 hours in both groups( P < 0.05), but returned to the baseline level 24 hours post IABP removal( P > 0.05) . Three patients in Group A and 2 patients in Group B developed minor limb ischemia( P > 0.05). No major limb ischemia in either group. Two patients in Group A suffered major bleeding and required blood transfusion or surgical intervention, whereas no patient had major bleeding in Group B. Eight patients had minor bleeding in Group A, but only 2 patients in Group B ( P <0.05). No clot deposit developed on IABP surface in either group. Conclusion: IABP is safe without routine anticoagulation therapy. Selecting appropriate artery approach and early detection intervention are key methods for preventing complications.

Colonoscopic polypectomy in anticoagulated patients

AIM:To review our experience performing polypectomy in anticoagulated patients without interruption of anticoagulation.METHODS: Retrospective chart review at the Veterans Affairs Palo Alto Health Care System. Two hundred and twenty five polypectomies were performed in 123 patients. Patients followed a standardized protocol that included stopping warfarin for 36 h to avoid supratherapeutic anticoagulation from the bowel preparation. Patients with lesions larger than 1 cm were generally rescheduled for polypectomy off warfarin. Endoscopic clips were routinely applied prophylactically. RESULTS: One patient (0.8%, 95% CI: 0.1%-4.5%) developed major post-polypectomy bleeding that required transfusion. Two others (1.6%, 95% CI: 0.5%-5.7%) had self-limited hematochezia at home and did not seek medical attention. The average polyp size was 5.1 ± 2.2 mm. CONCLUSION: Polypectomy can be performed in therapeutically anticoagulated patients with lesions up to 1 cm in size with an acceptable bleeding rate.

Acute upper gastrointestinal bleeding in patients on long-term oral anticoagulation therapy: Endoscopic findings, clinical management and outcome

AIM: Acute gastrointestinal bleeding is a severe complication in patients receiving long-term oral anticoagulant therapy. The purpose of this study was to describe the causes and clinical outcome of these patients. METHODS: From January 1999 to October 2003, 111 patients with acute upper gastrointestinal bleeding (AUGIB) were hospitalized while on oral anticoagulants. The causes and clinical outcome of these patients were compared with those of 604 patients hospitalized during 2000-2001 with AUGIB who were not taking warfarin. RESULTS: The most common cause of bleeding was peptic ulcer in 51 patients (45%) receiving anticoagulants compared to 359/604 (59.4%) patients not receiving warfarin (P<0.05). No identifiable source of bleeding could be found in 33 patients (29.7%) compared to 31/604 (5.1%) patients not receiving anticoagulants (P=0.0001). The majority of patients with concurrent use of non-steroidal anti-inflammatory drugs (NSAIDs) (26/35, 74.3%) had a peptic ulcer as a cause of bleeding while 32/76 (40.8%) patients not taking a great dose of NSAIDs had a negative upper and lower gastrointestinal endoscopy. Endoscopic hemostasis was applied and no complication was reported. Six patients (5.4%) were operated due to continuing or recurrent hemorrhage, compared to 23/604 (3.8%) patients not receiving anticoagulants. Four patients died, the overall mortality was 3.6% in patients with AUGIB due to anticoagulants, which was not different from that in patients not receiving anticoagulant therapy. CONCLUSION: Patients with AUGIB while on long-term anticoagulant therapy had a clinical outcome, which is not different from that of patients not taking anticoagulants. Early endoscopy is important for the management of these patients and endoscopic hemostasis can be safely applied.

Anticoagulation therapy prevents portal-splenic vein thrombosis after splenectomy with gastroesophageal devascularization

AIM:To compare the incidence of early portal or splenic vein thrombosis(PSVT) in patients treated with irregular and regular anticoagulantion after splenectomy with gastroesophageal devascularization.METHODS:We retrospectively analyzed 301 patients who underwent splenectomy with gastroesophageal devascularization for portal hypertension due to cirrhosis between April 2004 and July 2010.Patients were categorized into group A with irregular anticoagulation and group B with regular anticoagulation,respectively.Group A(153 patients) received anticoagulant monotherapy for an undesignated time period or with aspirin or warfarin without low-molecular-weight heparin(LMWH) irregularly.Group B(148 patients) received subcutaneous injection of LMWH routinely within the first 5 d after surgery,followed by oral warfarin and aspirin for one month regularly.The target prothrombin time/international normalized ratio(PT/INR) was 1.25-1.50.Platelet and PT/INR were monitored.Color Doppler imaging was performed to monitor PSVT as well as the effectiveness of thrombolytic therapy.RESULTS:The patients' data were collected and analyzed retrospectively.Among the patients,94 developed early postoperative mural PSVT,including 63 patients in group A(63/153,41.17%) and 31 patients in group B(31/148,20.94%).There were 50(32.67%) patients in group A and 27(18.24%) in group B with mural PSVT in the main trunk of portal vein.After the administration of thrombolytic,anticoagulant and antiaggregation therapy,complete or partial thrombus dissolution achieved in 50(79.37%) in group A and 26(83.87%) in group B.CONCLUSION:Regular anticoagulation therapy can reduce the incidence of PSVT in patients who undergo splenectomy with gastroesophageal devascularization,and regular anticoagulant therapy is safer and more effective than irregular anticoagulant therapy.Early and timely thrombolytic therapy is imperative and feasible for the prevention of PSVT.

Cognitive function and adherence to anticoagulation treatment in patients with atrial fibrillation

Background Medication adherence is an integral part of the comprehensive care of patients with atrial fibrillation （AF） receiving oral anticoagulations （OACs） therapy. Many patients with AF are elderly and may suffer from some form of cognitive impairment. This study was conducted to investigate whether cognitive impairment affects the level of adherence to anticoagulation treatment in AF patients. Me- thods The study involved 111 AF patients （mean age, 73.5±8.3 years） treated with OACs. Cognitive function was assessed using the Mini Mental State Examination （MMSE）. The level of adherence was assessed by the 8-item Mot^sky Medication Adherence Scale （MMAS-8）. Scores on the MMAS-8 range from 0 to 8, with scores 〈 6 reflecting low adherence, 6 to 〈 8 medium adherence, and 8 high adherence. Re- sults 46.9% of AF patients had low adherence, 18.8% had moderate adherence, and 33.3% had high adherence to OACs. Patients with lower adherence were older than those with moderate or high adherence （76.6 ±8.7 vs. 71.3 ~ 6.4 vs. 71.1 ± 6.7 years） and obtained low MMSE scores, indicating cognitive disorders or dementia （MMSE = 22.3 ± 4.2）. Patients with moderate or high adherence obtained high MMSE test results （27.5 ±1.7 and 27,5 ± 3.6）. According to Spearman＇s rank correlation, worse adherence to treatment with OACs was determined by older age （rs = -0.372） and lower MMSE scores （rs = 0.717）. According to multivariate regression analysis, the level of cognitive function was a significant independent predictor of adherence （b = 1.139）. Conclusions Cognitive impairment is an independent determinant of compliance with pharmacological therapy in elderly patients with AF. Lower adherence, beyond the assessment of cognitive function, is related to the age of patients.

Role of thrombus precursor protein in assessment of anticoagulation in patients with atrial fibrillation after mechanical heart valve replacement

Objective: To explore the role of thrombus precursor protein (TpP) in assessment of anticoagulation and predict the risk of thromboembolism in the patients with atrial fibrillation (AF) after mechanical heart valve replacement. Methods: TpP plasma concentration and international normalization ratio (INR) were measured in 45 patients with atrial fibrillation and 45 patients with sinus rhythm both after mechanical heart valve replacement. Twenty patients with non valvular heart diseases were selected as the control. Furthermore, the patients with AF were divided into groups based on different TpP plasma concentration and TpP plasma concentration and INR were analyzed. Results: After mechanical heart valve replacement, those with AF had higher TpP plasma concentration than those with sinus rhythm. It was found that discordancy existed between INR and TpP plasma concentration in the patients with AF. There were 28 AF patients with TpP plasma concentration lower than 6 μg/ml and without bleeding, who might be at the optimal anticoagulant state. The 95% confidence of the mean INR value was 1.90-2.30 in these patients and TpP plasma concentration was between 2.84-5.74 μg/ml. Conclusion: Patients with AF might face higher risk of thromboembolism after mechanical valve replacement; INR between 1.90-2.30 and TpP plasma concentration between 2.84-6 μg/ml might be the optimal anticoagulant range for patients with AF after mechanical valve replacement.

Thrombus precursor protein for monitoring anticoagulation in patients with mechanical valve prosthesis

Objective: To evaluate the plasma concentration of thrombus precursor protein (TPP) in patients after mechanical heart valve replacement, and to explore whether it can be used as a marker for monitoring anticoagulation. Methods: Totally 60 patients who took warfarin after mitral valve replacement and 20 control patients with non-valvular heart diseases were subjected in this study. Their plasma TPP concentration and international normalized ratio (INR) were determined, and compared not only between the anticoagulant patients and the control patients, but also between the patients with atrial fibrillaiton (AF, n=37) and the patients with sinus rhythm (SR, n=23) after mechanical valve replacement. The relationship between plasma TPP concentration and INR in the 60 anticoagulant patients was analyzed with linear regression. Results: It was found that the anticoagulant therapy effectively decreased plasma TPP concentration and elevated INR. In the anticoagulant group, the patients with AF had higher plasma TPP concentration than the others with sinus rhythm (P<0.05), although there was no significant difference in INR level between these 2 groups of patients (P>0.05). No significant correlation was found between plasma TPP concentration and INR in the anticoagulant patients (P>0.05). INR did not accord with plasma TPP concentration in several patients. Conclusion: INR can’t reflect the coagulation status and guide the anticoagulation correctly sometimes; TPP may be a valuable assistant marker for monitoring anticoagulation in patients with mechanical heart valve prothesis; Patients with AF may require higher density of anticoagulation and TPP is strongly suggested to be monitored in these patients.

Heparin bridge therapy and post-polypectomy bleeding

AIM To identify risk factors for post-polypectomy bleeding(PPB), focusing on antithrombotic agents. METHODS This was a case-control study based on medical records at a single center. PPB was defined as bleeding that occurred 6 h to 10 d after colonoscopic polypectomy and required endoscopic hemostasis. As risk factors for PPB, patient-related factors including anticoagulants, antiplatelets and heparin bridge therapy as well as polyp- and procedure-related factors were evaluated. All colonoscopic hot polypectomies, endoscopic mucosal resections and endoscopic submucosal dissections performed between January 2011 and December 2014 were reviewed. RESULTS PPB occurred in 29(3.7%) of 788 polypectomies performed during the study period. Antiplatelet or anticoagulant agents were prescribed for 210(26.6%)patients and were ceased before polypectomy except for aspirin and cilostazol in 19 cases. Bridging therapy using intravenous unfractionated heparin was adopted for 73 patients. The univariate analysis revealed that anticoagulants, heparin bridge, and anticoagulants plus heparin bridge were significantly associated with PPB(P < 0.0001) whereas antiplatelets and antiplatelets plus heparin were not. None of the other factors including age, gender, location, size, shape, number of resected polyps, prophylactic clipping and resection method were correlated with PPB. The multivariate analysis demonstrated that anticoagulants and anticoagulants plus heparin bridge therapy were significant risk factors for PPB(P < 0.0001). Of the 29 PPB cases, 4 required transfusions and none required surgery. A thromboembolic event occurred in a patient who took anticoagulant. CONCLUSION Patients taking anticoagulants have an increased risk of PPB, even if the anticoagulants are interrupted before polypectomy. Heparin-bridge therapy might be responsible for the increased PPB in patients taking anticoagulants.

Atrial fibrillation in older patients reducing stroke risk is not only about anticoagulation

Atrial fibrillation （AF） is associated with a five-fold increased risk of ischaemic stroke, stroke recurrence and mortality. Anticoagulant therapy may reduce the risk of recurrent stroke by approximately 60% and is more efficacious than anti-platelet agents.

Anticoagulation in elderly patients at high risk of atrial fibrillation without documented arrhythmias

Recent studies have suggested that patients with high CHA2DS2VASc-score [Congestive Heart failure, hyperten- sion, Age ≥ 75 years （doubled）, Diabetes, Stroke （doubled）, Vascular disease, Age 65-74 years, Sex category （female sex）] thromboembolic complications occurred irrespective of the presence of atrial fibrillation （AF） and anticoagulant therapy may be initiated irrespective of documented AF.

Analysis thrombolysis with anticoagulation treatment for early stage of deep vein thrombosis in the lower extremities

Objective: To explore the effect of thrombolysis with anticoagulation treatment for early stage of deep vein thrombosis of lower extremity. Methods: The clinical data of 106 patients at the early stage of deep vein thrombosis (DVT) in the lower extremities treated by thrombolysis with anticoagulation and dispersion drugs were analyzed retrospectively. Results: The thrombolytic effect was significant. After treatment, the deep veins were recanalized without regurgitation in 75.3% of the patients. The total effective rate was 100%. Only three patients had hemorrhagic complication, but none of the patients died. Conclusion: Thrombolysis with anticoagulation treatment is an effective and safe method for DVT at the early stage.