Extra-abdominal venous thromboses at unusual sites

Philadelphia chromosome-negative myeloproliferative neoplasms in younger adults: A critical discussion of unmet medical needs, with a focus on pregnancy

Myeloproliferative neoplasms (MPN) are traditionally regarded as a disease of older adults, though a not negligible fraction of cases occurs at a younger age, including women of childbearing potential. MPN in younger patients, indeed, offer several challenges for the clinical hematologist, that goes from difficulties in reaching a timely and accurate diagnosis to a peculiar thrombotic risk, with a relatively high incidence of thromboses in unusual sites (as the splanchnic veins or the cerebral ones). Moreover, the issue of pregnancy is recently gaining more attention as maternal age is rising and molecular screening are widely implemented, leading to a better recognition of these cases, both before and during pregnancy. In the present work we aim at discussing four clinical topic that we identified as areas of uncertainty or true unmet medical needs in the management of younger patients with MPN, with a particular focus on the topic of pregnancy. For each of these topics, we critically reviewed the available evidence that support treatment decisions, though acknowledging that recommendations in this field are mostly based on expert opinion or derived from guidelines of other clinical conditions that share with MPN a high vascular risk, as antiphospholipid syndrome. Taking into consideration both the lack of evidence-based data and the clinical heterogeneity of MPN, we support an individualized strategy of counseling and management for both young patients and for expectant mother with MPN.

Venous Thromboembolism in Denmark: Seasonality in Occurrence and Mortality

Background  Many cardiovascular conditions exhibit seasonality in occurrence and mortality, but little is known about the seasonality of venous thromboembolism.

Methods  Using Danish registries, we identified all patients with deep vein thrombosis, pulmonary embolism, splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis during 1977–2016. We tallied monthly deaths occurring within 90 days of the venous thromboembolism diagnosis. We estimated peak-to-trough ratios and timing of the peak of both diagnoses and deaths summed over all years of the study period. The departure from 1.0 of the peak-to-trough ratio measures the intensity of any seasonal pattern.

Results  We estimated a peak-to-trough ratio of 1.09 (95% confidence interval: 1.07–1.11) for deep vein thrombosis and 1.22 (1.19–1.24) for pulmonary embolism occurrence. The peak-to-trough ratios for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis occurrence were 1.10 (1.01–1.20), 1.19 (1.00–1.40), and 1.12 (1.07–1.17), respectively. The occurrence of all conditions peaked during winter or fall. In time trend analyses, the peak-to-trough ratio increased considerably for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis occurrence. In associated mortality, the peak-to-trough ratio for deep vein thrombosis was larger (1.15, 1.07–1.23) than that for pulmonary embolism (1.04, 1.01–1.08).

Discussion  Excess winter risks were modest, but more marked for pulmonary embolism occurrence than for deep vein thrombosis occurrence. The seasonal pattern intensified throughout the study period for splanchnic vein thrombosis, cerebral vein thrombosis, and retinal vein thrombosis. The winter peak in mortality following pulmonary embolism was smaller than that for deep vein thrombosis.

Retinal vein thrombosis and risk of occult cancer: A nationwide cohort study

Background

Retinal vein thrombosis has in case reports been reported a clinical sign of cancer, especially hematological cancer. However, it is unclear whether retinal vein thrombosis is a marker of underlying cancer, as is the case for deep venous thrombosis and pulmonary embolism. We investigated the risk of occult cancer in patients with retinal vein thrombosis.

Methods

A nationwide population‐based cohort study in Denmark on all patients diagnosed with a retinal vein thrombosis during 1994 and 2013. The main outcome measures were any cancer and site‐specific cancers <6 months, 6‐12 months, and 5 years following a retinal vein thrombosis diagnosis, as registered in the Danish Cancer Registry and the National Pathology Registry. We calculated the absolute cancer risk and computed standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) for cancer within <6 months, 6‐12 months, and 5 years following a retinal vein thrombosis diagnosis.

Results

Among 9589 patients with retinal vein thrombosis, we observed 1514 cancer cases. The risk of any cancer was 1.2% <6 months and 28.8% after 5 years. The <6 months SIR was 1.20 (95% CI 0.99‐1.44), 6‐12 months SIR was 1.15 (95% CI 0.94‐1.39), and the 5 years’ SIR was 1.08 (95% CI 1.03‐1.14). Stratification by age, gender, calendar year, and Charlson Comorbidity Index score did not change overall cancer risk estimates.

Conclusion

Retinal vein thrombosis was not an important clinical marker for occult cancer. An extensive diagnostic cancer workup does not appear warranted for retinal vein thrombosis patients.

Prescribing patterns of target-specific oral anticoagulants: an academic hospital perspective

Target-specific oral anticoagulants have been rapidly adopted into clinical practice for stroke prophylaxis and venous thromboembolism treatment, raising concerns about off-label prescribing practices. We conducted a retrospective review of consecutive patients prescribed dabigatran, rivaroxaban or apixaban prior to inpatient hospitalization over an 18-month period to examine the off-label prescribing frequency, contraindications and related complications. Chart review included baseline demographics, hospital admitting service, outpatient prescribing service, renal function, therapeutic indication, echocardiographic findings, contraindications, major bleeding events and vital status. We identified 160 patients who received a target-specific oral anticoagulant prior to hospitalization. Over half (53.1%) of the patients received rivaroxaban, 43.7% received dabigatran and 3.1% received apixaban. Atrial fibrillation (68.1%) and venous thromboembolism treatment (25.6%) were the most common indications. Ninety percent of patients had a U.S. Foods and Drugs Administration (FDA)-approved indication for therapy. Major bleeding events occurred in 4.4% of patients. Cardiology was the most common prescribing and admitting service (43.8 and 31.3%), and more frequently adhered to FDA-approved indications (97 vs. 84%, P = 0.01). There were no significant differences between prescribing services regarding major contraindications (P = 0.14) and major bleeding events (P = 0.77). Off-label prescription rates for target-specific oral anticoagulants were infrequent and not associated with increased adverse events.

[Sinus thrombosis and idiopathic intracerebral hypertension: Thrombophilia and hormonal influence as potentially relevant causal connections]

BACKGROUND

Cerebral venous sinus thrombosis and idiopathic intracerebral hypertension (IIH) can lead to impaired vision, which is why the suspected diagnosis is often initially made by an ophthalmologist.

PROBLEM AND AIMS

This study aimed at discovering common features between the two underlying conditions and provide ophthalmologists with concrete measures for differential diagnosis and for the management of affected patients based on these similarities.

MATERIAL AND METHODS

This article presents detailed profiles of the underlying conditions and compares the two, focusing on similarities with respect to risk factors.

RESULTS

The following common risk factor profiles of the two underlying conditions could be determined: (1) women before menopause, (2) administration of female hormones and (3) thrombophilia.

DISCUSSION

Based on these findings at least a partial overlap of both pathophysiologies is suspected. In particular, undiagnosed cerebral thrombosis or microthrombosis can cause IIH. This mechanism could explain the typical thrombophilic risk profile of IIH, which is analogous to that of cerebral venous sinus thrombosis, including the well-established interaction of estrogens and thrombophilic risk factors.

Cerebral thrombosis and myeloproliferative neoplasms

Myeloproliferative neoplasms (MPN) are acquired clonal disorders characterized by the proliferation of bone marrow myeloid cells. Different somatic mutations have been recently associated with MPN, the most common being JAK-2 V617F. Among MPN, polycythemia vera and essential thrombocythemia are particularly associated with an increased risk to develop thrombotic complications, either arterial or venous. Cerebrovascular events (stroke and transient ischemic attacks) are prevalent, accounting for approximately two-thirds of all events. Also cerebral vein thrombosis can complicate MPN and can be the first manifestation of the disease. Risk factors for thrombosis in patients with MPN are related or unrelated to the disease. Among the former there are cellular risk factors, such as increased white blood cell counts, vascular cell activation, endothelial dysfunction, and plasmatic risk factors, such as increased plasma viscosity, reduced levels of protein S, increased thrombin generation. The latter include increased age and previous thrombotic events. In addition, common cardiovascular risk factors (smoking, hypertension, diabetes, dyslipidemia, obesity) contribute to the pathogenesis of arterial events, whereas circumstantial risk factors (particularly oral contraceptive use and pregnancy/puerperium) to that of venous events. Primary prevention of arterial thrombosis with antiplatelet therapy is warranted in the majority of patients with MPN, whereas primary prevention of venous thrombosis is limited to anticoagulant prophylaxis during high-risk situations. Secondary prevention includes long-term antiplatelet therapy for arterial and short- or long-term anticoagulant therapy for venous thrombosis, depending on the risk factors present at the first event.