Relationship between the extent of deep venous thrombosis and the extent of acute pulmonary embolism as assessed by CT angiography

Feasibility study of hand-carried ultrasound-guided retrievable inferior vena cava filter placement

Background

With the development of ultrasonic diagnostic techniques in recent years, ultrasound-guided placement of inferior vena cava (IVC) filters has been widely used in clinics, and satisfactory results have been achieved. Our study aims to observe the accuracy of hand-carried ultrasound-guided retrievable vena cava filter placement, evaluate the feasibility and safety of this new method, and provide a scientific and effective interventional method and clinical data to prevent acute pulmonary embolism (PE) after battle injury of limbs.

Methods

Two hundred patients with post-traumatic thrombosis of the extremities were enrolled. The renal vein was located under the guidance of hand-carried ultrasound. The retrievable filter was fixed 1–2 cm below the opening of the renal vein. The self-expanding filter was used after the filter’s position was confirmed by injecting the contrast agent under the digital subtraction angiography (DSA) fluoroscopy.

Results

All the 200 patients underwent the operation successfully. The position of the hand-carried ultrasound localizer was consistent with the DSA localizer. All the filters were expanded smoothly. No complications related to the operation occurred.

Conclusions

The study concluded that the hand-carried ultrasound-guided retrievable vena cava filter placement has a high success rate and can prevent acute PE after limbs’ battle injury.

Detection of Deep Vein Thrombosis by Follow-up Indirect Computed Tomography Venography after Pulmonary Embolism

Background

Information regarding the incidence and risk factors for deep vein thrombosis (DVT) detected by follow-up computed tomographic (CT) venography after pulmonary embolism (PE) is sparse. The aim of the present study was to identify the predictors of DVT in follow-up CT images, and to elucidate their clinical significance.

Methods

Patients with PE were classified into the following three cohorts based on the time of indirect CT venography follow-up: within 1 month, 1 to 3 months, and 3 to 9 months after the initial CT scan. Each cohort was subdivided into patients with or without DVT detected by follow-up CT. Clinical variables were compared between the two groups.

Results

Follow-up CT revealed DVT in 61% of patients with PE within 1 month, in 15% of patients with PE at 1 to 3 months, and in 9% of patients with PE at 3 to 9 months after the initial CT scan. Right ventricular (RV) dilation on the initial CT (odds ratio [OR], 8.30; 95% confidence interval [CI], 1.89–36.40; p=0.005) and proximal DVT at the initial presentation (OR, 6.93; 95% CI, 1.90–25.20; p=0.003) were found to independently predict DVT in follow-up CT images within 1 month, proximal DVT at the initial presentation was found to independently predict DVT in follow-up CT images at 1 to 3 months (OR, 6.69; 95% CI, 1.53–29.23; p=0.012), and central PE was found to independently predict DVT in follow-up CT images at 3 to 9 months (OR, 4.25; 95% CI, 1.22–4.83; p=0.023) after the initial CT scan. Furthermore, the detection of DVT by follow-up CT independently predicted the recurrence of venous thromboembolism (VTE) (OR, 4.67; 95% CI, 2.24–9.74; p<0.001).

Conclusion

Three months after PE, DVT was not detected by follow-up CT in most patients with PE. RV dilation on the initial CT, central PE, and proximal DVT at the initial presentation were found to predict DVT on follow-up CT, which might predict VTE recurrence.

Risk marker associations with venous thrombotic events: a cross-sectional analysis

OBJECTIVE

To examine the interrelations among, and risk marker associations for, superficial and deep venous events-superficial venous thrombosis (SVT), deep venous thrombosis (DVT) and pulmonary embolism (PE).

DESIGN

Cross-sectional analysis.

SETTING

San Diego, California, USA.

PARTICIPANTS

2404 men and women aged 40-79 years from four ethnic groups: non-Hispanic White, Hispanic, African-American and Asian. The study sample was drawn from current and former staff and employees of the University of California, San Diego and their spouses/significant others.

OUTCOME MEASURES

Superficial and deep venous events, specifically SVT, DVT, PE and combined deep venous events (DVE) comprising DVT and PE.

RESULTS

Significant correlates on multivariable analysis were, for SVT: female sex, ethnicity (African-American=protective), lower educational attainment, immobility and family history of varicose veins. For DVT and DVE, significant correlates included: heavy smoking, immobility and family history of DVEs (borderline for DVE). For PE, significant predictors included immobility and, in contrast to DVT, blood pressure (BP, systolic or diastolic). In women, oestrogen use duration for hormone replacement therapy, in all and among oestrogen users, predicted PE and DVE, respectively.

CONCLUSIONS

These findings fortify evidence for known risk correlates/predictors for venous disease, such as family history, hormone use and immobility. New risk associations are shown. Striking among these is an association of PE, but not DVT, to elevated BP: we conjecture PE may serve as cause rather than consequence. Future studies should evaluate the temporal direction of this association. Oxidative stress and cell energy compromise are proposed to explain and predict many risk factors, operating through cell-death mediated triggering of coagulation activation.

Venous thromboembolism management: where do novel anticoagulants fit?

OBJECTIVE

To review novel oral anticoagulant (NOAC) trials in the treatment of venous thromboembolism (VTE) and the possible use of risk-stratification tools to guide their use in practice.

SCOPE

MEDLINE and Cochrane databases were searched to identify relevant journal articles published from January 1982 to February 2013. Additional references were obtained from articles extracted during the database search.

FINDINGS

NOACs have been developed to optimize VTE management and overcome the limitations of heparin and vitamin K antagonists (VKA). The AMPLIFY and EINSTEIN trials of apixaban and rivaroxaban, respectively, investigated single-drug management of VTE, whereas the edoxaban Hokusai-VTE trial and dabigatran RE-COVER and RE-COVER II trials investigated the use of NOACs with a heparin lead-in. The AMPLIFY and Hokusai-VTE trials are ongoing but the EINSTEIN and RE-COVER trials have demonstrated that rivaroxaban and dabigatran, respectively, are non-inferior to parenteral anticoagulants and warfarin in the management of VTE. Differences in study design complicate the application of study results to clinical practice. There are multiple validated DVT protocols that effectively and safely treat patients in outpatient settings. The pulmonary embolism (PE) severity index (PESI), simplified PESI (sPESI), and other prognostic tools have been used to risk stratify patients with PE by estimating mortality risk to guide outpatient eligibility.

CONCLUSIONS

NOACs provide physicians with new therapeutic options in the management of VTE. While heparin and VKAs compose the current standard treatment for VTE, their use will likely disappear as physicians grow comfortable with the adoption of NOACs. As studies have not clearly defined the efficacy of these agents in certain patient populations, further data in special patient populations and risk stratification through the use of VTE severity scores could potentially be adapted to guide anticoagulant management and outpatient treatment eligibility.