'Syringe-in-the-pocket'--a new approach to the outpatient thromboembolic prophylaxis of recurrent atrial fibrillation

Chronic anti-coagulation is not an attractive prospect to patients with atrial fibrillation (AF) after successful restoration of sinus rhythm. We researched the feasibility of self-screening for AF performed by instructed patients and, where necessary, prompt self-administration of an initial dose of low-molecular weight heparin (LMWH) prior to seeking medical attention. MATERIALS AND METHODS: Persistent AF qualified to elective cardioversion was our focus. Two hundred and sixty-three consecutive patients (M/F: 179/84, mean age: 59.8 +/- 8.6) were followed for a mean of 2.6 +/- 1.7 years. All patients were trained to identify AF by palpation of the radial pulse and to self-inject LMWH in the case of arrhythmia recurrence. Two hundred and thirty-two patients who correctly recognized AF recurrence and those without episodes of AF during 4 weeks after cardioversion were equipped with nadroparine after acenocoumarol discontinuation. In 191 patients AF recurred during further observation, 172 of them correctly identified AF episodes, including 162 who performed LMWH injections at home. Seven patients who had performed LMWH injections presented with sinus rhythm on arrival to hospital, six patients had AF. Two out of 21 patients who failed to identify their AF episodes and one patient of those who correctly detected the AF recurrence, but failed to perform LMWH self-injection suffered from ischemic stroke (sensitivity 96.1%, specificity 60.4%). No side effects of domiciliary LMWH self-injection were identified. CONCLUSION: When properly trained, the majority of patients can accurately diagnose AF recurrence and self-inject an initial dose of LMWH, which makes it a feasible and potentially attractive anti-thromboembolic strategy.     

Low molecular weight heparin versus unfractionated heparin for thromboprophylaxis in patients with acute atrial fibrillation: A randomized control trial

While long-term anticoagulation prevents ischemic stroke in high-risk patients with atrial fibrillation (AF), the optimal initial anti-thrombotic regime in acute AF is less well defined. We randomized 96 patients with new onset acute AF in an emergency admission ward to receive (1) once-daily preparation of low molecular weight heparin (LMWH), tinzaparin or (2) conventional intravenous unfractionated heparin (target APTT 50–70 s). 5 patients in unfractionated heparin group compared with no patients in LMWH group (0%, P = 0.04) developed ischemic stroke/transient ischemic attack during the first 48 h. An initial subcutaneous LMWH was safe and effective in ischemic stroke prevention in patients with acute AF.     

Interventional approach to reduce thromboembolic risk in patients with atrial fibrillation ineligible for oral anticoagulation.

The annual incidence of stroke in patients with nonrheumatic atrial fibrillation averages 5% per year and increases with age, left ventricular dysfunction, hypertension, diabetes or prior stroke. Since in nonrheumatic atrial fibrillation 91% of left atrial thrombi are located in the left atrial appendage, in patients ineligible for oral anticoagulation it was suggested the percutaneous closure of left atrial appendage as a therapeutic option to reduce embolic risk. In this article we report our initial experience with this procedure, which was uneventful and efficacious at short-term follow-up. In conclusion, the interventional approach in patients with atrial fibrillation ineligible for oral anticoagulation seems feasible and promising, and deserves further investigation.     

Cardioversion under the guidance of transesophageal echochardiograhy in persistent atrial fibrillation: results with low molecular weight heparin

BACKGROUND: Transesophageal echocardiography (TEE) guided cardioversion to restoration of sinus rhythm is a therapeutic option in patients with atrial fibrillation (AF). Anticoagulation at the time of and after cardioversion is necessary to prevent formation of new thrombus during atrial stunning period. We aimed to evaluate the efficacy and safety to TEE guided cardioversion with low molecular weight heparin (LMWH) in patients with atrial fibrillation. METHODS: We followed up 208 patients with persistent AF (mean age: 65.5+/-10.2 years) who were attempted TEE guided cardioversion. LMWH were used as an anticoagulant and warfarin therapy was continued. RESULTS: Cardioversion were performed in 183 patients. Sinus rhythm restored in 144 patients (78.7%). Mean follow up duration was 155 days. No cardiac death occurred. In the early follow up period (within 30 day) one thromboembolic event (0.54%) occurred in a patient who was cardioverted. Two patients who had not been cardioverted because of left atrial thrombus presented embolic stroke, one in early and another in late follow up period. All embolic complications occurred in patients who had been taking warfarin and whose INR level was subtherapeutic at the time of stroke. Sinus rhythm was maintained in 64% and total hemorrhagic complications occurred in 4.8% of the patients in long-term follow-up. CONCLUSION: TEE guided cardioversion with a short-term anticoagulation protocol using low molecular weight heparin is a safe and effective method in restoring and maintaining sinus rhythm and enables us to make earlier cardioversion in atrial fibrillation.     

Low molecular weight heparin versus unfractionated heparin for thromboprophylaxis in patients with acute atrial fibrillation: a randomized control trial

While long-term anticoagulation prevents ischemic stroke in high-risk patients with atrial fibrillation (AF), the optimal initial anti-thrombotic regime in acute AF is less well defined. We randomized 96 patients with new onset acute AF in an emergency admission ward to receive (1) once-daily preparation of low molecular weight heparin (LMWH), tinzaparin or (2) conventional intravenous unfractionated heparin (target APTT 50-70 s). 5 patients in unfractionated heparin group compared with no patients in LMWH group (0%, P = 0.04) developed ischemic stroke/transient ischemic attack during the first 48 h. An initial subcutaneous LMWH was safe and effective in ischemic stroke prevention in patients with acute AF.     

Predictors of atrial fibrillation recurrence in patients with long-lasting atrial fibrillation

BACKGROUND:

Limited data are available on the predictors of atrial fibrillation (AF) recurrence in patients with chronic AF.

OBJECTIVES:

To evaluate potential clinical, echocardiographic and electrophysiological predictors of AF recurrence after internal cardioversion for long-lasting AF.

METHODS:

A total of 99 consecutive patients (63 men and 36 women, mean age 63.33±9.27 years) with long-standing AF (52.42±72.02 months) underwent internal cardioversion with a catheter that consisted of two defibrillating coils. Shocks were delivered according to a step-up protocol. Clinical follow-up and electrocardiographic recordings were performed on a monthly basis for a 12-month period or whenever patients experienced symptoms suggestive of recurrent AF.

RESULTS:

Ninety-three patients (93.94%) underwent a successful uncomplicated cardioversion, with a mean atrial defibrillation threshold of 10.69±6.76 J. Immediate reinitiation of AF was observed in 15 patients (15.78%) of whom a repeated cardioversion restored sinus rhythm in 13 cases. Early recurrence of AF (within one week) was observed in 12 of 93 patients (12.90%). At the end of the 12-month follow-up period, during which seven patients were lost, 42 of the 86 remaining patients (48.84%) were still in sinus rhythm. Multivariate regression analysis showed that left atrial diameter (OR 1.126, 95% CI 1.015 to 1.249; P=0.025) and mitral A wave velocity (OR 0.972, 95% CI 0.945 to 0.999; P=0.044) were significant and independent predictors of AF recurrence, whereas age, left ventricular ejection fraction and AF cycle length were not predictive of arrhythmia recurrence.

CONCLUSION:

The present study showed that the left atrial diameter and mitral A wave velocity are the only variables associated with AF recurrence after successful cardioversion.     

Effective prophylaxis of thromboembolic complications with low molecular weight heparin in relapsed multiple myeloma patients treated with lenalidomide and dexamethasone

The immunomodulatory drugs thalidomide and lenalidomide have enhanced activity in patients with multiple myeloma (MM). Their efficacy is increased with the addition of dexamethasone, but significant rates of venous thromboembolism (VTE) are a severe side effect. Based on this evidence, it is recommended that VTE prophylaxis be prescribed in these patients. However, the optimal prophylaxis remains controversial. We analyzed 45 patients with relapsed MM who were treated with lenalidomide and dexamethasone at our center. The 45 patients received a total number of 192 cycles, respectively a median of three cycles; the median dosage of dexamethasone was 240 mg per cycle. All patients received prophylactic anticoagulation with low molecular weight heparin (LMWH). Moreover, 86.6% of patients had at least one additional VTE risk factor beside the myeloma-related risk. One out of 45 patients developed a deep vein thrombosis and pulmonary embolism. None of the other 44 patients had clinical signs of thrombosis or embolism and none of all patients experienced complications or side effects due to anticoagulation. Our results indicate that prophylactic anticoagulation with LMWH is safe and effective. Therefore, we propose LMWH should be used in patients being treated with lenalidomide and dexamethasone at least for the first 3 months of treatment until randomized trials have proven the equality of other pharmacological prophylaxis.     

Treatment failure of low molecular weight heparin bridging therapy before a cardiac surgery intervention in a patient with atrial fibrillation

From time to time, it may be necessary to interrupt oral anticoagulant therapy in preparation for surgical procedures. In high-risk patients or for longer periods, unfractionated or low-molecular-weight heparin bridging treatment has been reported safe. This case focuses attention on treatment failure of low molecular weight heparin bridging therapy in a patient with atrial fibrillation.     

低分子肝素治疗不稳定型心绞痛近期疗效观察

目的观察低分子肝素(LMWH)治疗不稳定型心绞痛(UAP)近期疗效及安全性。方法72例UAP患者随机分为2组,A组(n=36),阿斯匹林100mg/d,普通肝素300IU.kg-1.d-1,B组(n=36),阿斯匹林100mg/d,LMWH(速避林)86U/kg皮下注射,2次/d,疗效为7d,记录治疗前后心绞痛发作频率及静息心电图、动态心电图状况及凝血指标改变。结果两组治疗后心绞痛发作频率,发作时ST段改变程度、总缺血时间均较治疗前有显著改善(P<0.001),但两组比较仍有显著差异(P<0.05)。B组凝血指标在治疗前后均无显著差异(P>0.05),A组部分凝血指标在治疗前后有显著差异(P<0.05)。结论LMWH抗凝治疗UAP较普通肝素疗效肯定、安全。     

The home treatment of deep vein thrombosis with low molecular weight heparin, forced mobilisation and compression.

BACKGROUND: The aim of this prospective study was to analyse a group of patients with DVT (deep vein thrombosis) treated at home with LMWH (low-molecular weight heparin), compression and intensive mobilisation and to evaluate its feasibility, efficacy and safety from possible risks of pulmonary embolism. METHODS: From March 1997 to September 1999, 96 consecutive patients with diagnosed DVT were enrolled in a prospective study and treated at home with enoxaparin (Clexane Rh ne-Poulenc) administered subcutaneously at doses depending on body weight (1 mg/kg) b.i.d. for a minimum of seven days. Oral anticoagulants were started two days before discontinuing LMWH and given later for three months according to the haemocoagulation parameters. All patients wore elastic second degree compression stockings during the whole period of treatment and for 12 months there after. They were encouraged to walk 1-3 km daily. The sites of thrombosis were ilio-femoral vein--38 patients (40%), femoral or popliteal vein--32 patients (33%), crural veins--26 patients (27%). According to our surgical criteria two years ago 17 patients would have been operated on and trombectomy performed. The diagnosis was made by compression ultrasonography using a colour duplex scanner (Acuscan 125), by contrast phlebography, and platelet scintigraphy (Tromboscint test). Perfusion-ventilation scintigraphy of the lungs was performed only if there were clinical signs or even a suspicion of pulmonary embolism and on all patients with iliofemoral thrombosis. Perfusion gamagraphy of lungs was carried out on 51 patients where thrombosis was localised in proximal veins. RESULTS: In 27 patients there were signs of non-fatal pulmonary embolism (53%), but only seven patients (26%) suffered mild non-specific clinical signs; 20 patients with diagnosed pulmonary embolism (74%) were symptom-free. Out of 96 patients, three admitted to hospital (3%), 67 (70%) injected LMVH themselves and felt comfortable. Eight to 12 weeks after this treatment control sonography and phlebography were carried out in 70 patients to assess the localisation and progress of the thrombosis. In 51% (36 patients) partial and 31% (22 patients) total recanalisation was found. Five out of 96 complained of minor bleeding (5%). No thrombocytopenia was noticed. The first five days on home treatment were crucial. All patients were able to walk and live at home without difficulty. None of our patients with proximal deep vein thrombosis used a vena cava filter. CONCLUSIONS: Home treatment of DVT is possible and is effective, safe and less costly on average and per patient 40% in costs was saved compared with those of a hospital stay in spite of the greater expense of LMWH. The patients who received LMWH spent a mean of 1.2 days in the hospital, as compared with 12.7 days for the standard-heparin group.     

左旋氨氯地平对阵发性房颤并高血压患者房颤的影响

目的观察左旋氨氯地平对阵发性房颤并高血压患者P波离散度（Pd）、左房内径、高敏C反应蛋白（hs—CRP）水平、房颤发作情况的影响。方法将阵发性房颤并高血压患者100例随机分为治疗组（50例）和对照组（50例）。降压药物治疗组给予左旋氨氯地平,对照组给予坎地沙坦,随访1年,观察治疗前后Pd、左房内径、hs—CRP水平及房颤发作情况。结果至随访结束,在长期应用胺碘酮的患者中,对照组房颤复发17例,占81．0％,治疗组房颤复发22例,占95．7％,两组之间差异无统计学意义（x^2=1．122,P〉0．05）。未长期应用胺碘酮的患者,对照组、治疗组在7-12个月时房颤发作次数均较治疗前减少（t=2．823,P〈0．01;t=2．655,P〈0．05）,但两组之间差异无统计学意义（t=0．594,P〉0．05）。与治疗前比较,对照组、治疗组的Pd、左房内径、hs—CRP均降低（t=4．025-13．546,P〈0．01）,治疗后两组之间Pd、左房内径、hs—CRP比较,差异无统计学意义（t=1．234-1．514,P〉0．05）。结论左旋氨氯地平可减少阵发性房颤并高血压患者房颤的复发,降低Pd、左房内径和hs—CRP水平,其效果与坎地沙坦没有差异。     

Prevention of atrial fibrillation recurrence by statin therapy in patients with lone atrial fibrillation after successful cardioversion

The aim of this study was to investigate the effect of statin therapy on arrhythmia recurrence in patients with lone atrial fibrillation (AF). From July 1998 to December 1999, 62 patients with lone persistent AF lasting >/=3 months underwent successful external cardioversion. After a mean follow-up of 44 months, 85% had recurrence of AF. The use of statins was associated with a significant decrease in the risk of arrhythmia recurrence after successful cardioversion of AF. The result of this retrospective study demonstrates that the use of statins in patients with lone AF was associated with a significant decrease in the risk of arrhythmia recurrence after successful cardioversion.     

Predictors of arrhythmia recurrence in patients with lone atrial fibrillation.

AIMS: The need for antiarrhythmic drugs (AAD) after a first episode of atrial fibrillation (AF) is determined by the probability of recurrence. The aim of this study was to asses the probability of relapse and the predictors of recurrence in patients with idiopathic AF. METHODS AND RESULTS: A cohort of 98 consecutive patients younger than 65 years admitted at the emergency room because of an episode of symptomatic idiopathic (lone) AF was included in this study. On admission, a complete medical history was taken, and an echocardiogram and 24-h Holter monitoring were performed. Patients were seen at 3 and 6 months after the index episode. There were 35 (35.7%) patients with a new-onset AF episode and 63 (64.3%) with a recurrent AF episode. A majority of them were male (71%), with a mean age of 48+/-11 years. Patients with new-onset AF episodes did not receive AAD. At 6 month follow-up, 57% of all patients suffered at least one symptomatic AF relapse. Patients with AF relapses belong more often to the recurrent group vs. new-onset group of AF (65.1 vs. 34.9%, respectively, P = 0.03); they had larger LA diameter indexed for body surface area (BSA) (22.6+/-3.7 vs. 19.8+/-3.2 mm/m(2), P = 0.001), larger left ventricular end-systolic diameter (18.4+/-3.1 vs. 17.2+/-2.5 mm/m(2), P = 0.05) and a tendency towards a higher proportion of atrial tachycardia runs on Holter (66.7 vs. 50%, P = 0.09). Logistic regression analysis showed that the presence of previous episodes of AF (OR: 3.2; 95% CI; 1.0-8.0, P = 0.04) and a larger anteroposterior LA diameter (OR: 1.3; 95% CI; 1.1-1.6, P = 0.001) were independent predictors of AF recurrences at 6 months. CONCLUSIONS: The recurrence rate in lone AF patients is high. The presence of previous episodes and a mildly enlarged anteroposterior LA diameter increase the probability of relapse of lone AF.     

Massive choroidal hemorrhage associated with low molecular weight heparin therapy.

An 84-year-old woman with unstable angina pectoris was treated with subcutaneous enoxaparine (Clexane) for several days before presenting with severe pain and decreased vision in her left eye. The intraocular pressure was 70 mmHg, and fundus examination showed a pigmented choroidal lesion and associated choroidal and retinal detachment. Ultrasonography was consistent with choroidal hemorrhage, and she was diagnosed as having acute glaucoma secondary to massive subchoroidal hemorrhage. Medical control of the intraocular pressure resulted in a significant clinical improvement. Intraocular hemorrhage and angle-closure glaucoma are rare and previously unreported complications in patients treated with low molecular weight heparin. It is important to be aware of this ocular complication as these drugs are so often used.     

Pharmacokinetic studies of standard heparin and low molecular weight heparin in patients with chronic renal failure

The disappearance of the anticoagulant activities of a standard commercial heparin and of a low molecular weight (LMW) heparin (PK 10169), administered as single intravenous injections, was studied in patients with chronic renal failure. Heparin and LMW heparin anticoagulant activities were determined by activated partial thromboplastin time (APTT) and chromogenic assays of anti-Xa and anti-IIa activities. Following heparin injection, a fast initial decay of anticoagulant activities preceded a slow convex disappearance curve, in semilogarithmic plots. These experimental data are in agreement with a model based on a predominant saturable mechanism of elimination of heparin in patients with renal failure. The disappearance of LMW heparin anti-Xa activity was obviously different, with linear or concave elimination curves, and longer apparent half-life. Taken together, our kinetic data and those previously reported in normal subjects strongly suggest that the mechanism of elimination of the LMW heparin studied is not saturable (at least for the tested dosages), and that the kidneys play a minimal role in the elimination.     

Anticoagulant management by low-dose of low molecular weight heparin in patients with nonvalvular atrial fibrillation following hemorrhagic transformation and complicated with venous thrombosis: Five case reports and literature review

For patients with nonvalvular atrial fibrillation (NVAF) following hemorrhagic infarction (HI)/hemorrhage transformation (HT) and complicated with venous thrombosis, the management of anticoagulation is controversial. Our study intends to explore the safety and effectiveness of using low-dose of low molecular weight heparin (LMWH) to treat NVAF patients with HI (or HT) and complicated with venous thrombosis.Between January 2018 and January 2019, NVAF related acute ischemic stroke patients with HT/HI, hospitalized in the department of neurology or rehabilitation in our hospital, are enrolled retrospectively. Among them, those who were found to have venous thrombosis and undergo anticoagulation (LMWH) during the treatment were extracted. We investigate the efficacy and safety in those patients who have been treated with anticoagulant of LMWH.Five cases accepted LMWH within 3 weeks attributed to the appearance of venous thrombosis, and all of them did not display new symptomatic bleeding or recurrent stroke. However, based on the results of a head computed tomography scan, there were 2 cases of slightly increased intracranial hemorrhage, and then we reduced the dose of anticoagulant. In addition, color ultrasound showed that venous thrombosis disappeared or became stable.Patients with NVAF following HI/HT have a higher risk of thromboembolism. Early acceptance of low-dose LMWH as an anticoagulant is relatively safe and may gain benefit. However, in the process of anticoagulant therapy, we should follow-up head computed tomography/magnetic resonance imaging frequently, as well as D-dimer values, limb vascular ultrasound. Besides, the changes of symptoms and signs should be focused to judge the symptomatic bleeding or recurrent stroke. Furthermore, it is better to adjust anticoagulant drug dosage according to specific conditions.