Current management of cancer-associated venous thromboembolism in patients with thrombocytopenia: a retrospective cohort study.

Optimal management of venous thromboembolism (VTE) in cancer patients with thrombocytopenia is uncertain. We described current management and clinical outcomes of these patients. We retrospectively included a cohort of cancer patients with acute VTE and concomitant mild (platelet count 100,000-150,000/mm3), moderate (50,000-99,000/mm3), or severe thrombocytopenia (< 50,000/mm3). Univariate and multivariate logistic regression analyses explored the association between different therapeutic strategies and thrombocytopenia. The incidence of VTE and bleeding complications was collected at a 3-month follow-up. A total of 194 patients of whom 122 (62.89%) had mild, 51 (26.29%) moderate, and 22 (11.34%) severe thrombocytopenia were involved. At VTE diagnosis, a full therapeutic dose of LMWH was administered in 79.3, 62.8 and 4.6% of patients, respectively. Moderate (OR 0.30; 95% CI 0.12-0.75), severe thrombocytopenia (OR 0.01; 95% CI 0.00-0.08), and the presence of cerebral metastasis (OR 0.06; 95% CI 0.01-0.30) were independently associated with the prescription of subtherapeutic LMWH doses. Symptomatic VTE (OR 4.46; 95% CI 1.85-10.80) and pulmonary embolism (OR 2.76; 95% CI 1.09-6.94) were associated with the prescription of full therapeutic LMWH doses. Three-month incidence of VTE was 3.9% (95% CI 1.3-10.1), 8.5% (95% CI 2.8-21.3), 0% (95% CI 0.0-20.0) in patients with mild, moderate, and severe thrombocytopenia, respectively. The corresponding values for major bleeding and mortality were 1.9% (95% CI 0.3-7.4), 6.4% (95% CI 1.7-18.6), 0% (95% CI 0.0-20.0) and 9.6% (95% CI 5.0-17.4), 48.2% (95% CI 16.1-42.9), 20% (95% CI 6.6-44.3). In the absence of sound evidence, anticoagulation strategy of VTE in cancer patients with thrombocytopenia was tailored on an individual basis, taking into account not only the platelet count but also VTE presentation and the presence of cerebral metastasis.

Carotid atherosclerosis and risk for ischemic stroke in patients with atrial fibrillation on oral anticoagulant treatment.

BACKGROUND AND AIMS: Whether carotid atherosclerosis is associated with an increased risk for ischemic stroke in patients with atrial fibrillation (AF) on anticoagulant treatment is undefined. To explore this association, patients with AF on treatment with vitamin K antagonists were included in a multicenter, prospective study. METHODS: At inclusion in the study, patients underwent Doppler-ultrasonography for the assessment of carotid atherosclerosis and then were prospectively followed. Ischemic stroke or transient ischemic attack (TIA) were the primary study outcomes; death and its causes were reported. RESULTS: Overall, 587 patients were included in the study. At ultrasonography, 380 patients had carotid atherosclerosis (64.7%) and 45 internal carotid (ICA) stenosis ≥50% (7.7%). During a mean follow-up of 41 ±â€¯15 months, 30 patients had an ischemic stroke or TIA (1.49% per patient-year, 95% CI 0.96-2.03) and 81 patients died (4.01% per patient-year, 95% CI 3.16-4.86). Carotid atherosclerosis was associated with a significant increase in the risk for the composite of ischemic stroke or TIA or death after adjusting for CHA2DS2VASc (6.0% vs. 3.1% patient-year; HR 1.60, 95% CI 0.99-2.59; p = 0.05). ICA ≥50% was associated with a not significant increase in the risk of ischemic stroke or TIA (2.05% vs. 1.45% patient-year; HR 1.39, 95% CI 0.42-4.58) or all-cause death (6.1% vs. 3.8% patient-year; HR 1.66, 95% CI 0.83-3.32). CONCLUSIONS: In patients with AF, carotid atherosclerosis is a predictor for the composite of cerebrovascular events or death while on anticoagulant therapy. In patients with AF and carotid atherosclerosis, the clinical benefit of a more intense antithrombotic treatment should be evaluated.

Clonal populations of hematopoietic cells with paroxysmal nocturnal hemoglobinuria phenotype in patients with splanchnic vein thrombosis.

INTRODUCTION: Splanchnic vein thrombosis (SVT) is a serious complication in patients with paroxysmal nocturnal hemoglobinuria (PNH). Mutant PNH clones can be associated with an increased risk of SVT even in the absence of overt disease, but their prevalence in non-selected SVT patients remains unknown. MATERIALS AND METHODS: Patients with objective diagnosis of SVT and without known PNH were tested for the presence of PNH clone using high-sensitivity flow cytometric analysis. RESULTS: A total of 202 SVT patients were eligible, 58.4% were males, mean age was 54.6years (range 17-94), site of thrombosis was portal in 103 patients, mesenteric in 67, splenic in 37, and supra-hepatic in 10. SVT was associated with JAK2 V6167F in 28 of 126 (22.2%) screened patients, liver cirrhosis in 15.3% patients, recent surgery in 10.9%, and myeloproliferative neoplasm in 10.6%, whereas in 34.6% of patients neither permanent nor transient risk factors were detected. None of the patients had a clearly demonstrable PNH clone, but in two patients (0.99%, 95% CI 0.17-3.91) we observed very small PNH clones (size 0.014% and 0.16%) confirmed in two independent samples. One patient had portal vein thrombosis and no associated risk factors, the second had superior mesenteric vein thrombosis and inflammatory bowel disease. CONCLUSIONS: Very small PNH clones can be detected in patients with SVT and no clinical manifestations of disease. Future studies are needed to explore the potential role of this finding in the pathogenesis of SVT.

Incidence of thromboembolic complications in patients with atrial fibrillation or mechanical heart valves with a subtherapeutic international normalized ratio: a prospective multicenter cohort study.

Subtherapeutic international normalized ratio (INR) is frequently encountered in clinical practice, and patients with high-risk atrial fibrillation (AF) and with mechanical heart valve (MHV) with inadequate anticoagulation may be exposed to an increased risk of thromboembolic events (TE). However, there are no prospective data evaluating this risk. Consecutive patients with a history of stable anticoagulation, but with a subtherapeutic INR, were prospectively included. Data on use and dose of low-molecular weight heparin (LMWH) bridging therapy were collected. The incidence of objectively confirmed TE and of major bleeding events within 90 days after the index INR was assessed. Five hundred and one patients with INR value 0.5-1 INR units below the lower limit of the patient-specific target INR were included in the study (280 with MHV and 221 with AF and CHADS2 score ≥3). LMWH was prescribed for 64 patients (12.8%). During follow-up, seven patients had a TE (1.40%; 95% confidence interval 0.68, 2.86%; 5.58 events for 100 patients year). All the events occurred within 14 days after the index INR. When we consider only patients who did not receive bridging therapy, the incidence of TE was 1.14% (5 of 437 patients; 95% confidence interval 0.49, 2.64%; 4.58 events for 100 patients year). There were no major bleeding events. The risk of TE in this population was not negligible. Given the frequent observation of subtherapeutic INR levels when monitoring vitamin K antagonists, this finding warrants additional investigation to improve the management of these patients.

Risk of bleeding in low-risk atrial fibrillation patients on warfarin waiting for elective cardioversion.

INTRODUCTION: Systemic embolism is the most serious complication of cardioversion of atrial fibrillation (AF) and the immediate post-cardioversion period is associated with increased risk for thrombus formation. For this reason, treatment with vitamin K antagonist (VKA) is recommended for patients with AF. No information is available about bleeding risk related to this practice. METHODS: We performed a prospective multicentre study on 242 low-risk AF patients (CHADS(2) score 0-1) that started on warfarin for elective cardioversion to evaluate their bleeding risk. RESULTS: 178 were males (73.6%), mean age 63.9 ± 9.8 years, 60 patients (25%) were aged ≤ 59 years. Patients with CHADS(2) score = 0 were 73 (30%), those with CHADS(2) score = 1 were 169 (70%). Patients were on VKA treatment, maintained at INR intended therapeutic range 2.0-3.0, for a median time of 159 days (range 30-631)total follow-up period 127 patient-years (pt-yrs). Quality of anticoagulation and occurrence of bleeding events were recorded. Patients spent 23%, 64% and 8% of time below, within and above the intended therapeutic range, respectively. When we observed the INR levels, we found that 62 patients (25.6%) had INR>4.5 at least in one occasion, and 23 (9.5%) in ≥ 2. During follow-up, 2 patients had major bleeds (rate 1.6% pt-yrs), one fatal. No embolic complications were recorded. CONCLUSION: Our results show that low-risk AF patients, treated with VKA for elective cardioversion, carry a not irrelevant risk of bleeding. Efforts are required to properly select patients who could benefit from this procedure, reducing the time of warfarin exposure.

Seasonal and monthly variability in the incidence of venous thromboembolism. A systematic review and a meta-analysis of the literature.

Many studies showed that the occurrence of cardiovascular and cerebrovascular events exhibits a seasonal and monthly variation. Evidences of a seasonal and monthly variation in the incidence of venous thromboembolism (VTE) are more conflicting. We conducted a systematic review and a meta-analysis of the literature to assess the presence of an infradian rhythm of this disease. MEDLINE and EMBASE databases were searched up to January 2010. Monthly and seasonal variation in the incidence of VTE were analysed. We included studies analysing seasonal or monthly aggregation in the incidence of deep-vein thrombosis (DVT) and/or pulmonary embolism (PE) with an objective diagnosis of VTE. Two authors independently reviewed and extracted data. Seventeen studies for a total of about 35,000 patients were included. Twelve studies analysed the seasonal variation and 10 studies the monthly variation of VTE. Our results showed a significantly increased incidence of VTE in winter (chi-square 146.04, p <0.001), with a relative risk (RR) of VTE of 1.143 (99% CI [1.141, 1.144]), and a significantly increased incidence of VTE in January (chi-square 232.57, p <0.001) with an RR of VTE of 1.194 (99% CI 1.186, 1.203). Subgroup analyses including only idiopathic venous thromboembolic events confirmed the results of principal analyses. In conclusion, our data support the presence of an infradian pattern in the incidence of venous thromboembolic events, with a significantly higher risk in Winter and in January. Future studies are needed to better clarify the mechanisms behind this pattern.

Fondaparinux for the treatment of superficial vein thrombosis in the legs: the CALISTO study.

Superficial vein thrombosis (SVT) is quite a common disease that is associated with a non-negligible risk of progression to the deep venous system and, in some cases, of embolization to the lungs. However, SVT has traditionally been regarded as a benign disease and its optimal management has been poorly studied. Recently, fondaparinux, a subcutaneous, selective, indirect Factor Xa inhibitor, has been assessed in the treatment of SVT in the CALISTO study, with encouraging results. Fondaparinux was found to be more effective than placebo in reducing the risk of SVT extension or progression to deep vein thrombosis or pulmonary embolism without a significant increase in the risk of bleeding. Treatment of SVT with a once-daily, 2.5 mg injection of fondaparinux without the need for platelet monitoring appears as a simple, effective, and well-tolerated strategy, and has the potential to change the clinical management of SVT.

Managing bleeding complications in patients treated with the old and the new anticoagulants.

An increasing number of patients receive anticoagulant therapy to prevent and treat arterial or venous thromboembolism. The major complication of anticoagulant therapy is the increase of the individual bleeding risk. All anticoagulant drugs can cause haemorrhages, that can sometimes be life-threatening. Although heparins and the vitamin K antagonists have been the most widely used anticoagulants for decades, the correct management of bleeding complications associated with these agents has been poorly studied. More recently, new anticoagulant drugs, both parenteral and oral, have been approved for clinical use. Currently, none of these new agents has a specific antidote, and little advise can be given on how to manage a major bleeding event. The aim of this article is to describe the haemorrhagic risk and the management of bleeding complications associated with the principal anticoagulant drugs.