Are patients with thrombophilia and previous venous thromboembolism at higher risk to arterial thrombosis?

Factor V Leiden but not the factor II 20210G>A mutation is a risk factor for premature coronary artery disease: a case-control study in Iran

Background

Factor V Leiden (FVL) and factor II c.∗97G>A (rs1799963) are genetic risk factors for venous thromboembolism. Their contribution to coronary artery disease (CAD) is less clear.

Objectives

This study aimed to investigate the association between FVL, rs1799963, and premature CAD in Iranians.

Methods

We performed a genetic case-control study of 944 cases and 1081 controls from the premature CAD Milano-Iran study, including patients aged 18-55 (female) and 18-45 years (male) who underwent coronary angiography at the Tehran Heart Centre (Iran) in 2004-2011. Cases had luminal stenosis ≥50% in at least 1 main coronary artery or branch. Controls were age- and sex-matched with no CAD history. FVL and rs1799963 were genotyped using TaqMan SNP genotyping assays. Association was tested by logistic regression adjusted for matching factors and ethnicity. Effect modification by sex and cardiovascular risk factors (metabolic [obesity, hypertension, hyperlipidemia, and diabetes], and smoking) was assessed.

Results

The risk of premature CAD was increased by 50% in FVL carriers (adjusted odds ratio [adjOR] 1.54 [95% CI, 0.95-2.48]) and slightly reduced in rs1799963 carriers (adjOR 0.71 [95% CI, 0.40-1.27]). These effects were more pronounced in women than men (FVL, adjOR 1.66 vs 1.25; rs1799963, adjOR 0.60 vs 1.07). The risk of premature CAD was substantially increased in carriers of FVL with at least 1 metabolic risk factor compared with noncarriers without metabolic risk factors (adjOR 25.14 [95% CI, 12.51-50.52]).

Conclusion

FVL but not FII rs1799963 was associated with an increased risk of CAD in young Iranians. This risk increased considerably when combined with metabolic cardiovascular risk factors.

[Two cases of ischemic stroke due to low protein C caused by severe hyperthyroidism]

We reported two patients with acute ischemic stroke who had presented with symptoms of thyroid storm. Case1: A 43-year-old man abruptly developed left hemiparesis caused by the right middle cerebral artery occlusion. Cardiac evaluations revealed atrial fibrillation and left atrial enlargement. He had successful recanalization after reperfusion therapies. Case 2: A 66-year-old woman with severe bilateral middle cerebral artery stenosis presented with right hemiparesis and dysarthria. MRI revealed the acute infarction in the left frontal and parietal lobe. In both cases, protein C activity was decreased which could be related to severe hyperthyroidism. They concomitantly had arterial lesions where blood stasis could occur. Severe hyperthyroidism which could evoke the decreasing of protein C activity could be responsible to develop acute ischemic stroke.

Frequency and incidence of arterial events in patients with venous thromboembolism compared to the general population: A systematic review and meta-analysis of cohort studies

BACKGROUND

Recent literature hypothesized that patients with venous thromboembolism (VTE) are at increased risk of developing arterial ischemic events than general population without VTE. However, data summarizing the epidemiology of arterial events among VTE population compared to the general population are lacking.

METHODS

We conducted a systematic review and meta-analysis from current literature. PubMed, EMBASE, and Cochrane databases were searched between Jan 1, 2000, and December 31, 2020. Eligible studies were observational cohort studies published in English on arterial ischemic events in patients with VTE. Pooled effect size estimates and their 95% confidence intervals were obtained through random-effect models meta-analysis.

RESULTS

Twenty-eight observational studies enrolling 352,014 patients were identified and included. The pooled frequency of all arterial events was 6.1% (95% CI: 3.7-9.1) in patients with VTE and was significantly higher than the pooled frequency of 5.0% (95% CI: 3.1-7.2) found in controls, with a pooled risk ratio (RR) of 1.20 (95% CI: 1.01-1.44; p = 0.0422). The pooled incidence of all arterial events in patients with VTE was 11.3‰ per patient-year (95% CI: 4.6-18.0), and was significantly higher than the 9.2‰ per patient-year (95% CI: 2.0-16.4) obtained in controls (Incidence rate ratio, IRR: 1.32; 95% CI: 1.08-1.61; p = 0.0103). The pooled frequency and pooled incidence of arterial events were also higher in patients with unprovoked VTE than in patients with provoked VTE (RR: 2.12; 95% CI: 1.38-3.24; p = 0.0042; and IRR: 2.26, 95% CI: 1.45-3.49; p = 0.0032).

CONCLUSION

The frequency and incidence of arterial events in patients with VTE are considerably higher than in the general population, without VTE. Further studies are urgently needed to understand these differences and reduce the burden related to these diseases.

FUNDING

None.

Isquemia arterial aguda de las extremidades: ¿cómo abordarla?

La isquemia arterial aguda de las extremidades se define como la interrupción abrupta del flujo sanguíneo a determinado tejido, lo cual afecta la integridad, la viabilidad de la extremidad, o ambas. Las causas son múltiples y pueden resumirse en dos procesos fisiopatológicos, trombóticos o embólicos, con lo que se puede establecer el pronóstico y el tratamiento según su causa. El cuadro sindrómico es variable, y típicamente, se identifica con las cinco “P” de Pratt (pain, pallor, pulselessness, paralysis and paresthesia); se cuenta con múltiples ayudas diagnósticas, pero la arteriografía sigue siendo el método estándar para el diagnóstico. Con el advenimiento de los avances tecnológicos y los procedimientos vasculares, el salvamento de las extremidades ha venido en aumento y ha disminuido la extensión de las amputaciones, lo cual conlleva una mayor tasa de rehabilitación y de reincorporación a la vida social.

[ST elevation myocardial infarction in young adults: Is there an interest for thrombophilia screening?]

BACKGROUND

Coronary lesions characteristics as well as patient thrombogenicity can explain coronary events manifestation. In young patient, local conditions are usually less important and thrombogenicity could play a significant role. Assessing thrombophilia could be justified in young patients and may induce an adapted therapeutic management.

PURPOSE

We aimed to assess the prevalence of thrombophilia and therapeutic modification in young adults aged≤55 years admitted in our department for ST elevation myocardial infarction (STEMI).

METHODS

From January 2013 to January 2017, data on all patients aged≤55 years with STEMI admitted in emergency were retrospectively retrieved from our database. Thrombophilia investigation was made regarding clinical (with or without cardiovascular risk factors [CVRF]), biological and/or angiographic evaluation.

RESULTS

A total of 133 patients aged≤55 years with STEMI were included. Cardiac arrest occurred in 15 patients (11%). One or less CVRF were found in 47 patients (35%). Smoking was reported in 93 patients (70%) and drug addiction (cannabis, cocaine) in 19 patients (14%). A subset of 51 patients (38%) were screened for thrombophilia. Patients with thrombophilia assessment were younger, less active smokers and presented less CVRF than patients without investigation (P<0.001). Single vessel diseased was found in 88 patients (66%). No differences regarding coronary procedural characteristic were found between the two groups. The most frequently encountered aetiology, found in 122 patients (92%), was de novo intra-arterial thrombosis related to atherosclerosis. In patients with thrombophilia assessment (n=51), one or more abnormal biological results was found in 22 patients (43%) and a therapeutic adjustment was made in 6 patients (12%).

CONCLUSION

Thrombophilia screening in young STEMI adults showed an abnormality in 43% of cases. Antithrombotic treatment can be modified after its demonstration.

The Typical Presentation Spectrum of Deep Vein Thrombosis Associated with Inferior Vena Cava Malformations

Congenital malformations of the inferior vena cava (IVC) are rare and underreported. They can be a risk factor for deep venous thrombosis (DVT) as a result of inadequate venous drainage of the lower extremities through collateral circulation. The significant number of cases reported in the literature highlights their importance, warranting investigating their existence in younger individuals with idiopathic DVT of the lower extremities and pelvic veins. In this systematic review, we depict the typical presentation of IVC malformations, their management, and the management of their associated DVT.

The association between statin therapy during intensive care unit stay and the incidence of venous thromboembolism: a propensity score-adjusted analysis

Background

Studies have shown that statins have pleiotropic effects on inflammation and coagulation; which may affect the risk of developing venous thromboembolism (VTE). The objective of this study was to evaluate the association between statin therapy during intensive care unit (ICU) stay and the incidence of VTE in critically ill patients.

Methods

This was a post-hoc analysis of a prospective observational cohort study of patients admitted to the intensive care unit between July 2006 and January 2008 at a tertiary care medical center. The primary endpoint was the incidence of VTE during ICU stay up to 30 days. Secondary endpoint was overall 30-day hospital mortality. Propensity score was used to adjust for clinically and statistically relevant variables.

Results

Of the 798 patients included in the original study, 123 patients (15.4%) received statins during their ICU stay. Survival analysis for VTE risk showed that statin therapy was not associated with a reduction of VTE incidence (crude hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.28-1.54, P = 0.33 and adjusted HR 0.63, 95% CI 0.25-1.57, P = 0.33). Furthermore, survival analysis for hospital mortality showed that statin therapy was not associated with a reduction in hospital mortality (crude HR 1.26, 95% CI 0.95-1.68, P = 0.10 and adjusted HR 0.98, 95% CI 0.72-1.36, P = 0.94).

Conclusion

Our study showed no statistically significant association between statin therapy and VTE risk in critically ill patients. This question needs to be further studied in randomized control trials.

Factor V Leiden thrombophilia

Factor V Leiden is a genetic disorder characterized by a poor anticoagulant response to activated Protein C and an increased risk for venous thromboembolism. Deep venous thrombosis and pulmonary embolism are the most common manifestations, but thrombosis in unusual locations also occurs. The current evidence suggests that the mutation has at most a modest effect on recurrence risk after initial treatment of a first venous thromboembolism. Factor V Leiden is also associated with a 2- to 3-fold increased relative risk for pregnancy loss and possibly other obstetric complications, although the probability of a successful pregnancy outcome is high. The clinical expression of Factor V Leiden is influenced by the number of Factor V Leiden alleles, coexisting genetic and acquired thrombophilic disorders, and circumstantial risk factors. Diagnosis requires the activated Protein C resistance assay (a coagulation screening test) or DNA analysis of the F5 gene, which encodes the Factor V protein. The first acute thrombosis is treated according to standard guidelines. Decisions regarding the optimal duration of anticoagulation are based on an individualized assessment of the risks for venous thromboembolism recurrence and anticoagulant-related bleeding. In the absence of a history of thrombosis, long-term anticoagulation is not routinely recommended for asymptomatic Factor V Leiden heterozygotes, although prophylactic anticoagulation may be considered in high-risk clinical settings. In the absence of evidence that early diagnosis reduces morbidity or mortality, decisions regarding testing at-risk family members should be made on an individual basis.

Cytomegalovirus infection is associated with venous thromboembolism of immunocompetent adults--a case-control study

Cytomegalovirus (CMV) seems to contribute to the development of venous thromboembolism (VTE) in immunocompromised patients whereas literature data on the role in immunocompetent individuals are mainly limited to case reports. This study aimed to investigate if cytomegalovirus infection contributes to the development of VTE in immunocompetent individuals. CMV-IgG and CMV-IgM antibody titres, CMV-IgG avidity and CMV-DNA were identified in samples from 166 VTE patients and from 166 healthy blood donors matched for gender and age. CMV-IgG antibodies were found more frequently in VTE patients compared to controls [57.8% vs. 44.0%; adjusted OR 1.75 (95% CI 1.13-2.70); p = 0.016]. Accordingly, median CMV-IgG titres were significantly higher in the case group (89.4 vs. 1.8 AU/ml; p = 0.002). Although the overall rate was low, CMV-IgM antibodies were detected more often among cases than controls. The difference was significant in patients with an unprovoked VTE event [7.4% vs. 0.6%; adjusted OR 5.26 (95% CI 1.35-20.8); p = 0.017]. CMV-IgG antibodies of almost all VTE patients (98.9%) and controls (98.6%) were found to be of high avidity. The rate of positive CMV-DNA samples was low and not different between cases and controls. With the exception of age, no association was found between CMV seropositivity and established VTE risk factors within the VTE group. CMV infection seems to play a role in the development of VTE in immunocompetent patients. Recurrent infection might be more important than acute CMV infection.