Risk of cardiovascular disease in double heterozygous carriers and homozygous carriers of F5 R506Q (factor V Leiden) and F2 (prothrombin) G20210A: a retrospective family cohort study

Acute Myocardial Infarction in Patients with Hereditary Thrombophilia-A Focus on Factor V Leiden and Prothrombin G20210A

Factor V (FV) Leiden and prothrombin G20210A are the most common hereditary thrombophilias. While their role in venous thromboembolism is well known, there are still uncertainties regarding their relationship with arterial thrombotic events, especially coronary ones. Our research, based on an in-depth analysis of the available literature, provides up-to-date information on the relationship between FV Leiden and prothrombin G20210A and acute myocardial infarction. FV Leiden and prothrombin G20210A screening should be implemented only in select cases, such as acute coronary syndrome in young individuals and/or in the absence of traditional cardiovascular risk factors and/or in the absence of significant coronary artery stenosis at angiography. Their identification should be followed by the implementation of optimal control of modifiable traditional cardiovascular risk factors to reduce the risk of recurrent events and genotyping and genetic counseling of all family members of affected cases for proper prophylaxis. An extended dual antiplatelet therapy (DAPT) may be considered, given the lower risk of bleeding under DAPT conferred by FV Leiden.

How I treat unexplained arterial thrombosis

Most arterial thrombotic events have a clear atherosclerotic or cardioembolic etiology, but hematologists are frequently asked to assist in the diagnosis and management of a patient with a nonatherosclerotic and noncardioembolic arterial event, referred to here as an unexplained arterial thrombosis. Because there is an assorted list of factors that can precipitate an arterial event, we present a systematic diagnostic approach to ensure consideration of not only primary hypercoagulable disorders, but also pro-thrombotic medications or substances, vascular and anatomic abnormalities, and undiagnosed systemic disorders, such as malignancy and autoimmune diseases. We also review existing literature of the role of hypercoagulable disorders in arterial thrombosis and discuss our approach to thrombophilia workup in patients after an unexplained arterial event. We conclude with 3 representative cases to both illustrate the application of the outlined diagnostic schema and discuss common management considerations, specifically the selection of anticoagulation vs antiplatelet therapy for secondary prevention.

Impact of double heterozygosity for Factor V Leiden and Prothrombin G20210A on the thrombotic phenotype

INTRODUCTION

Because of the rarity of double heterozygosity for Factor V Leiden (FVL) and Prothrombin (FII) G20210A, little is known about the thrombotic phenotype in double heterozygotes.

MATERIAL AND METHODS

In a retrospective cohort study of patients referred for a thrombophilia work-up, we investigated whether double heterozygotes (n = 138) exhibit a more severe thrombotic phenotype compared with single FVL or FIIG20210A heterozygotes, single FVL homozygotes, or wildtype carriers.

RESULTS

The risk of venous thromboembolism (VTE) was higher for female but not male double heterozygotes compared with single heterozygotes (FVL: 2.51, 95%CI 1.55-4.08, FIIG20210A: 1.75, 95%CI 1.14-2.68) and wildtype carriers (HR 2.53, 95%CI 1.58-4.05) but not compared with FVL homozygotes (HR 1.31, 95%CI 0.94-1.83). Female double heterozygotes developed VTE nearly a decade earlier than wildtype carriers and FVL heterozygotes (mean 44.2 vs. 52.6 and 52.2 years), most often in association with oral contraceptives. Spontaneous VTE and arterial thromboembolic events were not more frequent in double heterozygotes compared with the other genotype groups. Deep vein thrombosis (DVT) of the lower limb was the predominant VTE location in double heterozygotes, atypical vein thrombosis was rare. A phenomenon that has been described as the FVL paradox, a higher proportion of isolated DVT than pulmonary embolism, was also found for double heterozygotes.

CONCLUSION

The thrombotic phenotype in double heterozygotes resembles the appearance of the thrombotic phenotype in FVL carriers but the thrombotic risk is aggravated by women-specific risk factors.

Genetic and lifestyle predictors of ischemic stroke severity and outcome

BACKGROUND

Different models that include clinical variables and blood markers have been investigated to predict acute ischemic stroke treatment course and recovery.

AIM

The aim of the study was to investigate associations between lipid levels, lifestyle factors, hemostatic (F5, F2, SERPINE1, F13A1, and FGB), and atherogenic (APOA5 and ACE) gene variants and acute ischemic stroke (AIS) severity.

MATERIALS AND METHODS

This study included 250 patients with AIS in which F5, F2, SERPINE1, F13A1, FGB, APOA5, and ACE genotypes were determined. Total cholesterol (TC), high-density cholesterol, low-density cholesterol, and triglycerides concentrations were measured within 24 h of the AIS onset. Examination of the neurological deficit was done using National Institutes of Health Stroke Scale/Score (NIHSS).

RESULTS

APOA5 genotype [TC + CC] was more frequent (P = 0.026) in patients with the NIHSS score ≥ 21. Univariate regression analysis has shown that triglycerides (OR 0.55, 95% CI 0.34-0.91; P = 0.019), obesity (0.28, 95% CI 0.10-0.73; P = 0.010), age (OR 1.08, 95% CI 1.04-1.13; P < 0.001), and APOA5 genotype (TC + CC) (OR 2.40, 95% CI 1.10-5.25; P = 0.034) are significantly associated with a severe stroke. When all variables were included in model age (OR 1.06, 95% CI 1.01-1.11; P = 0.018), obesity (OR 0.25, 95% CI 0.08-0.77; P = 0.016) and APOA5 genotype (TC + CC) (OR 3.26, 95% CI 1.29-8.23; P = 0.012) remained significant for the risk of severe AIS.

CONCLUSION

APOA5 genotype (TC + CC), age, and obesity could be used as prognostic risk factors for a very severe stroke (NIHSS ≥ 21).

Thrombophilic risk of individuals with rare compound factor V Leiden and prothrombin G20210A polymorphisms: an international case series of 100 individuals

The risk of thrombosis in individuals with rare compound thrombophilias, homozygous factor V Leiden (FVL) plus heterozygous prothrombin G20210A (PTM), homozygous PTM plus heterozygous FVL, and homozygous FVL plus homozygous PTM, is unknown. We identified, worldwide, individuals with these compound thrombophilias, predominantly through mailing members of the International Society on Thrombosis and Haemostasis. Physicians were sent a clinical questionnaire. Confirmatory copies of the genetic results were obtained. One hundred individuals were enrolled; 58% were female. Seventy-one individuals had a venous thrombosis (includes superficial and deep vein thrombosis, and pulmonary embolism), 4 had an arterial thrombosis and 6 had both. Nineteen individuals had never had a thrombotic event. Thrombosis-free survival curves demonstrated that 50% of individuals had experienced a thrombotic event by 35 yrs of age, while 50% had a first venous thromboembolic event (VTE; includes all venous thrombosis except superficial thrombosis) by 41 yrs of age; 38.2% of first VTEs were unprovoked. 37% of patients had at least one VTE recurrence. Seventy percent of first pregnancies carried to term and not treated with anticoagulation were thrombosis-free. In conclusion, patients with these rare compound thrombophilias are not exceedingly thrombogenic, even though they have a substantial risk for VTE.

Association of Hemostatic Gene Polymorphisms With Early-Onset Ischemic Heart Disease in Egyptian Patients

The association between hereditary thrombophilia and venous thrombosis is well established but controversial data exist with respect to arterial thrombosis. We performed a pilot study on 31 patients with acute myocardial infarction (AMI), 21 patients with unstable angina (UA), and 20 healthy volunteers to investigate the role of various hemostatic gene polymorphisms in young Egyptian patients, who survived their first ischemic heart disease (IHD). Thrombophilic gene polymorphisms were tested using multiplex polymerase chain reaction and reverse-hybridization technique. We showed an increased risk of AMI with factor V (FV) Leiden and prothrombin G20210A heterozygosity. The increased risks of UA was associated with GA and A allele of fibrinogen β-455G→A polymorphism. Conversely, factor XIII (FXIII) Val34Leu GT and T allele were protective in the UA group. Nevertheless, the prevalence of FV H1299R, plasminogen activator inhibitor 1 4G/5G, glycoprotein IIIa C1565T, 5,10-methylenetetrahydrofolate reductase C677T, and A1298C mutations did not differ between patients with IHD and controls. The data have clinical implications regarding screening and thromboprophylaxis in high-risk individuals younger than 40 years.