Ultrasonography of contralateral veins in patients with unilateral deep-vein thrombosis

The prevalence of and predictors to indicate bilateral venous duplex ultrasound testing to detect contralateral asymptomatic lower extremity deep venous thrombosis in patients with acute symptomatic lower extremity deep venous thrombosis

OBJECTIVE

The goal of this study was to determine the prevalence of and predictors to indicate bilateral venous duplex ultrasound (DU) to detect contralateral asymptomatic deep venous thrombosis (DVT) in patients with acute symptomatic lower extremity DVT.

METHODS

Venous DU reports along with medical records of the patients were collected from February 2005 to April 2012 in a tertiary university hospital in Botucatu, Brazil. All patients with DVT detected in one lower extremity routinely underwent contralateral limb venous DU examination. Exclusion criteria were previous DVT in the contralateral asymptomatic limb, thrombophlebitis, workup for pulmonary embolism, and bilateral symptomatic lower extremities.

RESULTS

Scans were done in 579 patients to rule out contralateral lower extremity DVT whenever DVT was confirmed in the ipsilateral lower extremity; of these, 108 patients (18.6%) had an abnormal finding on DU examination for DVT in the contralateral limb, which was proximal DVT in 71.5%. Age >60 years (odds ratio [OR], 3.33; 95% confidence interval [CI], 1.447-7.670), malignant disease (OR, 5.21; 95% CI, 1.943-14.015), and the association of trauma plus malignant disease (OR, 7.11; 95% CI, 1.640-30.863) were the main predictors.

CONCLUSIONS

Age >60 years, malignant disease, lower extremity trauma, inpatient status, and recent hospitalization are risk factors associated with a high incidence of asymptomatic contralateral lower extremity DVT in patients with ipsilateral lower extremity DVT. Therefore, we recommend routine performance of a venous DU examination on the contralateral lower extremity whenever these risk factors are present in patients with ipsilateral lower extremity DVT.

Is it useful to also image the asymptomatic leg in patients with suspected deep vein thrombosis?

BACKGROUND

Venous ultrasonography is the cornerstone of the diagnostic work-up in patients with suspected deep vein thrombosis (DVT). Significant variations exist in clinical practice between centers and/or countries, e.g. proximal vs. whole-leg ultrasound, serial tests vs. single test, and combination with clinical probability and D-dimer testing. Fewer data exist on the need for bilateral leg imaging.

OBJECTIVES

To assess the yield of bilateral leg ultrasonography in patients with suspected DVT.

PATIENTS AND METHODS

This was a retrospective cohort study of consecutive patients with clinically suspected DVT. A single whole-leg ultrasound scan was performed in all patients. We extracted information on demographics, risk factors, clinical signs, pretest probability, side of clinical suspicion, and ultrasound results.

RESULTS AND CONCLUSIONS

Among the 2804 included patients, 609 (21.8%) patients had a positive ultrasound finding. A total of 20 patients (0.8%; 95% confidence interval [CI] 0.5-1.2%) had a thrombus diagnosed in both the symptomatic leg and asymptomatic leg. Moreover, five patients (0.2%; 95% CI 0.1-0.5%) did not have a thrombus in the symptomatic leg but had a thrombus in the asymptomatic leg. Two of 2540 patients with unilateral symptoms had no proximal DVT in the symptomatic leg and a proximal DVT in the asymptomatic leg (0.08%; 95% CI 0.0-0.3%). In summary, systematic imaging of both legs in patients with suspected DVT has a very low yield, and therefore does not appear to be justified.

Incidence and risk factors for bilateral deep venous thrombosis of the lower limbs

The incidence of bilateral deep venous thrombosis in patients with single limb or bilateral symptoms was determined using duplex scan examination. In a prospective study, 157 inpatients with clinical suspicion of deep venous thrombosis underwent duplex scan evaluation of the lower extremities. Demographic characteristics, physical examination data, and risk factor information were collected. In all, 57 (36.3%) patients evaluated presented echographic evidence of acute deep venous thrombosis. Forty-six individuals presented unilateral thrombosis, and 11 patients presented bilateral disease (19.3% of all thrombosis, 7.0% of all patients). Sensitivity and specificity of clinical examination in identifying bilateral thrombosis was 27.2% and 93.3%, respectively. For the risk factors evaluated, active human immunodeficiency virus disease and iliofemoral thrombosis presented an increased risk for bilateral thrombosis (P = .045 and P = .049, respectively). The high incidence of bilateral deep venous thrombosis justifies bilateral duplex scan examination. Active human immunodeficiency virus disease and proximal thrombosis were risk factors for bilateral disease.

Site and clinical outcome of deep vein thrombosis of the lower limbs: an epidemiological study

Clinical outcomes of patients diagnosed with venous thromboembolic disease (VTED) have rarely been assessed on large series of patients from single institutions. This was work based on our practice to routinely screen all suspected pulmonary embolism (PE) and deep venous thrombosis (DVT) patients with bilateral proximal and distal venous US was designed to evaluate survival, recurrence and cancer occurrence in patients diagnosed with symptomatic or asymptomatic DVT and to assess their relationship with the site of the DVT (proximal vs. distal, bilateral vs. unilateral). Our study is based on the cross-matching of the VTED register of the Grenoble University Hospital with the local Cancer Register and community mortality data. Survival analyses were performed with the Kaplan-Meier method; prognostic variables were tested using the log-rank test. A total of 1913 patients with a DVT of the lower limbs from 1993 to 1998 were included (57% women; mean age, 69 years). Of these, 1018 patients were diagnosed with proximal DVT (156 bilateral) and 895 distal DVT (112 bilateral). PE was associated in 760 patients. Patients with PE and no detected DVT were not included. At 2 years, adjusted survival rates were 80% in patients with unilateral-distal DVT, 67% in bilateral-distal, 72% in unilateral-proximal and 65% in bilateral-proximal DVT patients. The cumulated VTED recurrence rates were 7.7% in unilateral-distal DVT, 13.3% when DVT was bilateral-distal, 14% when unilateral-proximal and 13.2% when bilateral-proximal. The rate of new cancer was 6.4% in unilateral-distal DVT, 10.8% when it was bilateral-distal, 6.5% when unilateral-proximal and 6.1% when bilateral-proximal. Based on a large series of unselected patients, our results show that the site of the DVT and principally the bilaterality provides important prognostic information that may be used in the setting up of medical strategies.

Is bilateral duplex scanning necessary in patients with symptoms of deep venous thrombosis?

BACKGROUND

Venous duplex ultrasound scanning (VDUS) has been shown to be an accurate non-invasive means to diagnose symptomatic deep venous thrombosis (DVT). The aim of our study was to determine whether bilateral VDUS is necessary in patients who present with symptoms of DVT.

METHODS

We retrospectively reviewed the results of bilateral lower extremity VDUS performed on 1029 inpatients at Royal Prince Alfred Hospital in the 24 months from 1 January 1998 to 31 December 1999.

RESULTS

Of the 1029 patients, 705 (69%) presented with unilateral symptoms and 324 (31%) with bilateral symptoms. The overall incidence of DVT was 168 (16% of 1029 patients). In 705 patients with unilateral symptoms the diagnosis of DVT was confirmed in 120 (17.0%), of whom 20 (16.7%) had unsuspected bilateral DVT. There were 12 patients (1.7% of the 705 patients) who had DVT in the asymptomatic limb, without DVT identified in the symptomatic limb. Overall there were 32 (5% of 705) patients with unilateral symptoms who had unsuspected DVT in the asymptomatic limb. Of the 20 patients with bilateral DVT, only one patient had more extensive DVT in the asymptomatic limb than in the symptomatic limb, that was therefore likely to alter treatment. Bilateral symptoms of DVT were present in 324 (31.5%) patients, 48 (14.8%) of whom were found to have DVT. Nineteen (39.6%) of these DVTs were bilateral.

CONCLUSION

Overall the diagnostic yield of VDUS was low in this study, with an incidence of 16% of DVT detected in symptomatic patients. Techniques that improve the diagnostic yield of VDUS in symptomatic patients are required. A significant proportion (23%) of the DVT detected in this study were bilateral, and a small but significant proportion (10%) of DVT found in patients presenting with unilateral symptoms were only in the asymptomatic contralateral limb. Our study supports bilateral VDUS in symptomatic inpatients, as the detection of DVT in asymptomatic limbs aids future patient management if symptoms develop in the asymptomatic limb.

Is bilateral ultrasound scanning of the legs necessary for patients with unilateral symptoms of deep vein thrombosis?

PURPOSE

The purpose of this study was to determine the necessity of bilateral lower-extremity venous duplex ultrasound scanning in patients with unilateral symptoms of deep vein thrombosis (DVT).

PATIENTS AND METHODS

A retrospective review of 1080 bilateral venous duplex scans was performed. Patients were randomly selected from a total of 7922 studied between May 1998 and May 2000. Data on patient age, sex, comorbidity, and the reason for ultrasound scan were compiled. Forty percent (435/1080) of patients presented with unilateral symptoms of lower-extremity DVT. This group was further analyzed according to their status as inpatients or outpatients.

RESULTS

DVT was diagnosed in 26.9% (117/435) of the patients. Of the inpatients found to have DVT, the thrombus was confined to the symptomatic leg in 23.8% (38/159), thrombus was present just in the asymptomatic leg in 8/159 (5.0%), and thrombus was found in both legs in 8/159 (5.0%). In the outpatient group, thrombus was confined to the symptomatic leg in 21.0% (58/276) and found in both legs in 1.8% (5/276). None of the 276 outpatients had DVT isolated in the asymptomatic leg.

CONCLUSION

Routine bilateral lower-extremity venous duplex studies are not necessary in outpatients presenting with unilateral symptoms. In many outpatients, a single-limb study will suffice. If a patient is found to have a DVT on the symptomatic side, then we believe that a bilateral study is indicated. We do believe that routine bilateral scanning of inpatients remains justified. This algorithm may save technician time and increase vascular laboratory efficiency.

Idiopathic deep vein thrombosis and subsequent cancer: suggestions for a patient-oriented and practical approach

The relationship between an idiopathic deep vein thrombosis and a cancer is well established. It is not clear yet whether all patients with an idiopathic deep vein thrombosis should be thoroughly investigated for an occult cancer or only some. As a matter of fact, once a physician is faced with a patient who has an idiopathic deep vein thrombosis, three approaches are possible, mainly: 1) a wait and see approach; 2) a limited investigation: and 3) an extensive or invasive investigation. No sure criteria for the selection of the patients who should be extensively investigated are available. Suggestions have been made in this regard. Negative family or personal history for thrombosis, advanced age, deep vein thrombosis of upper limbs, existence of silent deep vein thrombosis in contralateral leg, tendency to relapse and/or to migrate, constitutional symptoms, or smoking may represent important clues that may justify an extensive study. This patient-oriented approach is mainly based on the experience of the caring physician.