Thomas Schwarz

Complete compression ultrasonography of the leg veins as a single test for the diagnosis of deep vein thrombosis.

Noninvasive diagnosis of deep vein thrombosis (DVT) is based on ultrasound examination of the leg veins, usually restricted to only compression of the proximal veins (CUS). Patients with negative CUS findings require a second examination or a combination with other tests, which impairs clinical efficiency. In this prospective outcome study, 1646 consecutive patients with clinically suspected DVT were examined once by a standardized protocol of complete compression ultrasound comprising all proximal and distal veins (CCUS) as the only diagnostic test. The examination was equivocal in 15 patients (1% technical failure rate). Another 366 patients (22%) were tested positive for proximal DVT, distal DVT, muscle vein thrombosis, or phlebitis. Of 1265 patients in whom CCUS findings were negative, 242 met exclusion criteria for follow-up (age <18, life expectancy <3 months, other reasons for anticoagulation, postthrombotic lesions of the leg veins, or lack of informed consent). During the 3 months of follow-up, three of 1023 patients with negative CCUS findings experienced a symptomatic venous thromboembolic event (0.3% [95% CI 0.1%-0.8%]). We conclude that the CCUS protocol has a low technical failure rate and is safe with respect to excluding DVT, thereby reducing the diagnostic workup of patients with suspected DVT to a single ultrasound examination.

Therapy of isolated calf muscle vein thrombosis with low-molecular-weight heparin

There are no data from prospective studies concerning the treatment of isolated calf muscle vein thrombosis (soleal and gastrocnemial muscle veins), found in 20–40% of patients with lower extremity thrombosis of the calf. We investigated the outcome in two cohorts of consecutive patients, the first receiving low-molecular-weight heparin for 10 days at therapeutic doses and compression therapy; the second cohort, compression therapy alone. In patients on therapeutic heparin (n = 52), no progression to deep vein thrombosis occurred [0%; 95% confidence interval (CI), 0–6.8%]. Patients without anticoagulation (n = 32) showed a statistically significant higher percentage of progression into the deep calf veins (25%; 95% CI, 11.5–43.4%) as well as recurrent muscle vein thrombosis. No symptomatic pulmonary embolism or bleeding event occurred; one patient died in each group, both related to malignancy. The data suggest a need for short-term anticoagulation in such patients to prevent further thromboembolic complications. Randomized prospective studies are now warranted in a larger study population.

Interobserver Agreement of Complete Compression Ultrasound for Clinically Suspected Deep Vein Thrombosis

The interobserver variability of compression ultrasound of proximal and distal veins in clinically suspected deep vein thrombosis was assessed. One hundred one symptomatic legs of all patients referred for clinically suspected deep vein thrombosis on 21 consecutive workdays were examined by two investigators independently according to a standardized protocol of complete compression ultrasound (CCUS) with 28 predefined venous segments between groin and ankle. Incompressible vein segments were defined as thrombotic. Cohens kappa coefficient was used to calculate interobserver variability regarding diagnosis of deep vein thrombosis. Kappa for entire lower extremity was 0.94 (95% CI, 0.87-1). Kappa for proximal veins was 1; for calf veins 0.9 (95% CI, 0.79-1). For the posterior tibial veins and peroneal veins, kappa was 0.84 (95% CI, 0.66-1) and 0.77 (95% CI, 0.59-0.94), respectively. The results show that almost complete interobserver agreement can be achieved in compression ultrasound of both proximal and distal deep veins conducted according to a standardized examination protocol in clinically suspected deep vein thrombosis.

Eligibility for home treatment of deep vein thrombosis : prospective study

Low molecular weight heparin is safe and effective for the treatment of deep vein thrombosis.1 We have recently shown in a randomised study that immobilisation is not necessary.2 The results challenge the traditional notion that these patients must be treated in hospital. For selected patients, outpatient treatment has been shown to be safe and effective. 3 4 We determined the proportion of patients who still require admission to hospital and why.nnBetween 1 November 1998 and 15 August 1999 all patients presenting to the vascular diagnostics unit of the University Hospital Dresden, Germany, as outpatients with acute deep vein thrombosis in the leg were prospectively evaluated regarding eligibilty for home treatment. We defined acute deep vein thrombosis as non-compressible deep veins on ultrasonography (UM9 …

Deep vein and isolated calf muscle vein thrombosis following long-haul flights : pilot study

The risk of venous thromboembolism associated with long-haul flights is the subject of controversy. In a prospective, controlled study, we examined 160 passengers before and after return from a long-haul flight and 160 age-matched and sex-matched, non-travelling volunteers using venous compression ultrasound. Deep vein thrombosis was not observed in either group. Isolated calf muscle vein thrombosis (ICMVT) was present in 4/160 (2.5%) flight passengers and in 1/160 (0.6%) controls. All subjects with ICMVT were clinically asymptomatic, and ICMVT was located in the soleal muscle veins in all four subjects. Three of the four passengers with ICMVT had other risk factors for thrombosis.

Frequency of Polymorphisms in the B-domain of Factor V Gene in APC-resistant Patients ☆

In this study we investigated a group of patients in whom a resistance to APC (activated protein C) was found but no Leiden mutation existed in the presence of missense mutations in the first 1200 bp of the Exon 13 (B-domain) in the factor V (FV) gene. The determination of the APC response was performed using the Immunochrom(R) APC response Test Kit. The mutations were determined by temperature gradient gel electrophoresis and DNA sequencing. In the APC-resistant patients without the FV Leiden, we found 4 silent mutations (2298C>T, 2325T>C, 2379A>G, 2391A>G) and 4 missense mutations (2540A>C, 2663A>G, 2684A>G, 2863A>G), which code for the amino acids N789T (GenBank Accession # AF119360), K830R, H837R, and K897E. In all of the patients and controls, the polymorphisms at nucleotide positions 2391, 2663, 2684, and 2863 appeared to be associated. In the major allele all bases are A (A allele) and in the minor allele are G (G allele). A significantly lower G allele frequency was observable in the patient group than in the control group (0.14 vs. 0.31; p<0.05). The frequency of the 2540C allele, which is associated with the 2379G and the 4070G allele (non-Leiden!), did not differ significantly between the patient and the control groups. We suggest that the G allele, which is not associated with the FV Leiden mutation, as well as the [2379G; 2540C; 4070G] allele have no influence on the APC cofactor function itself, or only subtly as determined in the test systems used.

SPONTANEOUS THROMBOSIS OF THE DEEP DORSAL PENILE VEIN IN A PATIENT WITH THROMBOPHILIA

While superficial dorsal penile vein thrombosis has been associated with inherited thrombophilia, 1 and deep dorsal penile vein thrombosis following trauma 2 and thrombosis of the corpora cavernosa have previously been described, to our knowledge there are no reports of spontaneous deep dorsal penile vein thrombosis. We report such a case and discuss the functional and therapeutic issues of this disorder. CASE REPORT

Complete compression ultrasound for the diagnosis of proximal and distal deep venous thrombosis: a retrospective outcome study

Background: Compression ultrasound is considered the preferred test for the diagnosis of deep vein thrombosis of the leg (DVT). Since sensitivity for distal thrombosis is low additional tests are required. We developed a protocol of complete compression ultrasound of all venous segments of the leg (CCUS). A retrospective outcome study was performed to get an estimate of the rate of indeterminate results necessitating repeated testing as well as for the clinical safety of CCUS in a cohort of consecutive, unselected patients. Patients and methods: Case records of all patients referred for clinical suspicion of deep vein thrombosis within a three months period were reviewed. Patients with negative CCUS were followed directly or via the general practitioner in order to know whether an episode of venous thromboembolism had been documented since the initial CCUS. Results: 132 inpatients and 154 outpatients were identified. Clinical probability was high in 50 patients, medium in 142, and low in 94. The first CCU...BACKGROUNDnCompression ultrasound is considered the preferred test for the diagnosis of deep vein thrombosis of the leg (DVT). Since sensitivity for distal thrombosis is low-additional tests are required. We developed a protocol of complete compression ultrasound of all venous segments of the leg (CCUS). A retrospective outcome study was performed to get an estimate of the rate of indeterminate results necessitating repeated testing as well as for the clinical safety of CCUS in a cohort of consecutive, unselected patients.nnnPATIENTS AND METHODSnCase records of all patients referred for clinical suspicion of deep vein thrombosis within a three months period were reviewed. Patients with negative CCUS were followed directly or via the general practitioner in order to know whether an episode of venous thromboembolism had been documented since the initial CCUS.nnnRESULTSn132 inpatients and 154 outpatients were identified. Clinical probability was high in 50 patients, medium in 142, and low in 94. The first CCUS was negative in 209 cases. Five patients (1.8%) had repeated CCUS within the next 7 days because of incomplete visualisation of the distal veins and turned out to be negative as well. Of all 214 patients with negative CCUS a clinical follow-up information was obtained after 168 +/- 25 days. Five patients had died, none due to pulmonary embolism. In two patients deep vein thrombosis had been documented (0.9% [95% CI: 0.1-3.3%]) 148 and 172 days after CCUS, respectively.nnnCONCLUSIONnCCUS for diagnosis of DVT needs to be repeated in very few cases only. Clinical safety seems to fall into the same range as with combined algorithms and should be tested in a prospective design. Patients with medium and high probability showed a very low incidence of DVT within three months following CCUS; therefore, they may be included in a prospective outcome study.

Popliteal entrapment syndrome: non-invasive diagnosis and complete recovery after surgery in an 11-year-old boy

Abstract We present an unusual case of popliteal entrapment syndrome type I in an 11-year-old boy. Presenting symptoms were exercise-related pain and pallor in his left lower leg. The diagnosis of popliteal entrapment syndrome was established by acral plethysmography, colour-coded Doppler sonography and MRI. After myotomy of the gastrocnemius muscle the symptoms resolved completely. Post-operative duplex scan showed normal blood flow, even in plantar flexion of the foot.

Investigation of genotype-dependent differences in factor V activity as well as response to activated protein C by application of different methods.

Coagulation factor V has been at the centre of investigation for several years. In addition to factor V Leiden, various other polymorphisms are becoming the object of interest. Different results have been published about the association of the HR2 haplotype with decreased factor V levels and with reduced response to activated protein C (APC). Due to the central position of factor V in the clotting process, its activity can be determined in both thromboplastin-based and activated partial thromboplastin time (aPTT)-based assays. A multitude of assays are known for the determination of APC response. The aim of our study was to investigate whether different methods disclose genotype-dependent differences in factor V activity as well as APC response. Three wild-type carriers, three carriers homozygous for the R2 allele (4070G), and three carriers homozygous for the G allele (2391G, 2663G, 2684G, 2863G) were investigated. For each individual plasma sample, the factor V activity was determined using 12 different reagent combinations of three different thromboplastins, three different aPTT reagents, and two different factor V deficient plasma sources. The determination of factor V activity in the thromboplastin system revealed differences between the genotypes. These differences were independent of the thromboplastin reagent and the factor V-deficient plasma. The aPTT system exhibited a dependency on the aPTT reagent and the factor V-deficient plasma. Analysis of APC response disclosed genomic differences in specific test systems only. One type of assay could be more appropriate than other types in dependence of the position of genomic variations. Therefore, the applied assay is an important influential factor in investigations of functional consequences of genomic variations.