The ultrasound compression sign to diagnose temporal giant cell arteritis shows an excellent interobserver agreement.

OBJECTIVES: To compare the diagnostic performance between a vascular specialist and a rheumatologist not familiar with vascular ultrasound when applying the compression sign for the diagnosis of temporal arteritis. METHODS: Sixty consecutive patients with suspicion of giant cell arteritis were examined by both examiners. Compression of the temporal artery on both sides (stem and both branches) was performed to define whether signs of vasculitis, no vasculitis or an indefinite result were present. Each examiner was blinded to the result of the other. RESULTS: In 59/60 patients, the examiners found an identical result. The interobserver agreement (Krippendorf alpha) was 0.92. CONCLUSIONS: The new compression sign for the diagnosis of temporal arteritis is a simple and robust sonographic marker with an excellent interobserver agreement.

Risk of falls and bleeding in elderly patients with acute venous thromboembolism.

OBJECTIVE: Whether or not a high risk of falls increases the risk of bleeding in patients receiving anticoagulants remains a matter of debate. METHODS: We conducted a prospective cohort study involving 991 patients ≥ 65 years of age who received anticoagulants for acute venous thromboembolism (VTE) at nine Swiss hospitals between September 2009 and September 2012. The study outcomes were as follows: the time to a first major episode of bleeding; and clinically relevant nonmajor bleeding. We determined the associations between the risk of falls and the time to a first episode of bleeding using competing risk regression, accounting for death as a competing event. We adjusted for known bleeding risk factors and anticoagulation as a time-varying covariate. RESULTS: Four hundred fifty-eight of 991 patients (46%) were at high risk of falls. The mean duration of follow-up was 16.7 months. Patients at high risk of falls had a higher incidence of major bleeding (9.6 vs. 6.6 events/100 patient-years; P = 0.05) and a significantly higher incidence of clinically relevant nonmajor bleeding (16.7 vs. 8.3 events/100 patient-years; P < 0.001) than patients at low risk of falls. After adjustment, a high risk of falls was associated with clinically relevant nonmajor bleeding [subhazard ratio (SHR) = 1.74, 95% confidence interval (CI) = 1.23-2.46], but not with major bleeding (SHR = 1.24, 95% CI = 0.83-1.86). CONCLUSION: In elderly patients who receive anticoagulants because of VTE, a high risk of falls is significantly associated with clinically relevant nonmajor bleeding, but not with major bleeding. Whether or not a high risk of falls is a reason against providing anticoagulation beyond 3 months should be based on patient preferences and the risk of VTE recurrence.

Temporal artery compression sign--a novel ultrasound finding for the diagnosis of giant cell arteritis.

PURPOSE: In patients with suspected giant cell arteritis (GCA), a search for the perivascular halo sign, a sophisticated color duplex ultrasound (CDU) finding, at experienced centers reliably identifies inflamed temporal arteries (TA). We tested whether TA compression in patients with GCA, a simple, largely operator-independent maneuver, elicits contrasting echogenicity between the diseased artery wall and the surrounding tissue (compression sign). MATERIALS AND METHODS: 80 individuals with suspected GCA were prospectively enrolled in this single-center study. In all study participants, bilateral ultrasound examination of the TA established the presence/absence of the halo and compression sign. A positive compression sign was defined as visibility of the TA upon transducer-imposed compression of the artery. Based on ACR criteria, a team of specialized physicians independently grouped patients as GCA versus non-GCA. RESULTS: 43/80 study participants were grouped as GCA. Both the halo sign and the compression sign were positive in 34/43 patients in the GCA group, and negative in all 37/37 of the non-GCA group, resulting in a sensitivity of 79 % and a specificity of 100 % for both the halo and the compression sign. CONCLUSION: In this cohort of individuals with suspected GCA, the halo sign and the compression sign were equal in their diagnostic performance. The simplicity of the compression sign suggests a level of reliability warranting further evaluation.

Prospective comparison of noninvasive, bedside ultrasound methods for assessing central venous pressure.

PURPOSE: To prospectively evaluate the accuracy of noninvasive central venous pressure (CVP) assessment by compression ultrasound of a forearm vein (CUS), inferior vena cava (IVC-C) and internal jugular vein collapsibility (IJV-C) compared to invasive CVP measurement (invCVP) as the gold standard. MATERIALS AND METHODS: CUS, IVC-C and IJV-C were performed in a random sequence in 81 consecutive intensive care patients with simultaneous invCVP monitoring. Examiners were blinded to invCVP and previous examinations. RESULTS: Median invCVP was 12.0 mmHg (range 1 - 23). CUS, IVC-C and IJV-C could be obtained in 89 %, 95 % and 100 % of cases, respectively, within a median time of 188 sec [IQR 125; 270], 133 sec [IQR 100; 211] and 60 sec [IQR 50; 109], respectively. The Spearman correlation coefficient between invCVP and CUS, IVC-C, and IJV-C was 0.485 95 %-CI [0.25; 0.65], -0.186 [-0.42; 0.07], and -0.408 [-0.59; -0.18], respectively. The median absolute difference between CUS and invCVP was 3 mmHg [IQR 2; 6.75]. CVP was categorized as low (< 7 mmHg; collapsibility > 0.6), normal (7 - 12 mmHg; collapsibility 0.6 - 0.2) and high (> 12 mmHg; collapsibility < 0.2) as prespecified. The proportions of identical CVP classifications compared to invCVP were 61.4% 95%-CI [49.3%; 72.4%] with CUS, 48.7% [37.4%; 60%] with IVC-C and 51.3% [40.3%; 62.3%] with IJV-C (p > 0.10 for all pair-wise comparisons). CONCLUSION: The overall ability of CUS, IVC-C and IJV-C to assess invCVP was only moderate. CUS seems to be the preferable method if absolute CVP values are needed. IJV-C seems to be the fastest and most easily acquirable method, and thus may be especially valuable in emergency rooms.

Clinical relevance of musical murmurs in color-coded duplex sonography of peripheral and visceral vessels.

BACKGROUND: Musical murmurs (MMs) are Doppler phenomena which sound like high-frequency musical sounds. They reflect high and turbulent flow within relevant stenoses and were first described in degenerated bioprosthetic valves and later in intracranial vessels and were associated either with high-grade arterial stenosis, small collateral arteries or carotid cavernous fistulas. Objective of this article is to illustrate the spectrum of imaging of MMs observed in renal, intestinal and peripheral vessels. PATIENTS AND METHODS: Four experienced vascular ultrasound laboratories had been asked to report their cases with documented musical tones in color coded duplex sonography (CCDS) within a two year observational period (2008 and 2009). Documented Doppler findings and corresponding clinical data were analyzed. RESULTS: MMs were found in 18 patients with an incidence of 0.05 % and were observed in high grade stenosis in hemodialysis access (n = 5), in post-biopsy arteriovenous fistulas after renal transplantation (n = 3), in renal transplant artery (n = 1) and vein (n = 3), stenoses in peripheral (n = 2) and intestinal arterial disease (n = 2), and in peripheral veins (n = 2). CONCLUSIONS: The so called musical murmurs are a rare but potentially relevant finding in CCDS. They are caused by a variety of underlying pathologies with different clinical implications, however correct interpretation is mandatory since urgent therapy might be necessary.

Gadofosveset enhanced MR phlebography for detecting pelvic and deep vein leg thrombosis.

BACKGROUND: Deep venous thrombosis is mainly diagnosed by ultrasound today. In some instances diagnosis is challenging and magnetic resonance angiography could be an attractive alternative. Gadofosveset is a blood pool contrast agent with some favourable properties for this purpose. PATIENTS AND METHODS: We investigated eight patients with proven deep venous thrombosis by Gadofosveset enhanced MR phlebography. We performed a 3D gradient-echo sequence with an overall measurement time of 9 minutes and 6 seconds. One minute after injection of Gadofosveset in a concentration of 0.12 ml/kg body weight images were acquired. Thrombi were visualised by their lack of luminal contrast filling. RESULTS: Thrombi were visualised in all patients. In one patient with extended thrombosis a previously undiagnosed ovarian adenocarcinoma was detected additionally. CONCLUSIONS: Deep venous thromboses in lower extremities can be visualised reliably by performing MR phlebography with blood pool contrast agent Gadofosveset. Visualisation of the complete venous system is feasible. This investigation method may be performed in patients difficult to investigate with ultrasound or may be used for planning interventional procedures.

Use of B-type natriuretic peptide to predict blood pressure improvement after percutaneous revascularisation for renal artery stenosis.

OBJECTIVES: The purpose of this study was to evaluate the utility of B-type natriuretic peptide (BNP) to predict blood pressure (BP) response in patients with renal artery stenosis (RAS) after renal angioplasty and stenting (PTRA). METHODS: In 120 patients with RAS and hypertension referred for PTRA, 24-h ambulatory BP recordings were obtained before and 6 months after intervention. BNP was measured before, 1 day and 6 months after PTRA. RESULTS: BP improved in 54% of patients. Median BNP levels pre-intervention were 97 pg ml(-1) (interquartile range (IQR) 35-250) and decreased significantly within 1 day of PTRA to 62 pg ml(-1) (IQR 24-182) (p < 0.001), remaining at 75 pg ml(-1) (IQR 31-190) at 6 months. The area under the receiver operating curve for pre-intervention BNP to predict BP improvement was 0.57 (95% confidence interval (CI) 0.46-0.67). Pre-intervention BNP >50 pg ml(-1) was seen in 79% of patients with BP improvement compared with 56% in patients without improvement (p = 0.01). In a multivariate logistic regression analysis, BNP >50 pg ml(-1) was significantly associated with BP improvement (odds ratio (OR) 4.0, 95% CI 1.2-13.2). CONCLUSIONS: BNP levels are elevated in patients with RAS and decrease after revascularisation. Although BNP does not seem useful as a continuous variable, pre-interventional BNP >50 pg ml(-1) may be helpful to identify patients in whom PTRA will improve BP.

Giant arteriovenous fistula after implantation of a percutaneous left ventricular assist device.

INTRODUCTION: Percutaneous left ventricular assist devices are an important tool in the management of patients with severe cardiogenic shock. Limited experiences concerning vascular complications after long term implantation of these devices exist. We report on a large arteriovenous fistula after placement of a left ventricular assist device, which has not been described in the literature. The arteriovenous fistula was of clinical relevance because it represented a supplementary cardiac burden in a patient with impaired left ventricular function after a severe myocardial infarction.

Color Doppler ultrasound and computed tomographic angiography for perforator mapping in DIEP flap breast reconstruction revisited: A cohort study.

INTRODUCTION: Preoperative imaging by Computed Tomographic Angiography (CTA) has been promoted a gold standard tool for perforator mapping in abdominally based microsurgical breast reconstruction, while Color Doppler Ultrasound (CDU) has lost its popularity. As the CTA X-ray exposure might have long-term consequences for patients, CDU has regained importance for preoperative workup in our center. Our aim was to revisit the role of CDU by comparing the reliability of CDU and CTA in predicting intraoperative perforator selection. MATERIALS AND METHODS: We performed a retrospective chart review study of patients who underwent microsurgical breast reconstructions with DIEP flaps at our institution. Both CTA and CDU were performed prior to the surgery, and both imaging entities were thoroughly examined by the surgical team. Perforator identification, number, size, and location were assessed and correlated with CTA and CDU data and with intraoperative findings. RESULTS: We identified 98 patients who received 125 DIEP flap surgeries. A significantly stronger correlation was found between CDU and intraoperative findings of perforator detection and size (p<0.0001) and selection (r = 0.9987, CI 0.9981-0.9991, p < 0.0001 and r = 0.01, CI -0.18-0.2, p = 0.91, respectively), when compared with CTA data. If none of the preoperative imaging studies matched intraoperative perforator selection, an association with a higher incidence of flap loss (Odds ratio 4.483, CI 0.5068-39.65, p = 0.2171) was found. CONCLUSIONS: Our data suggests that CDU might regain relevance as a safe and reliable preoperative imaging study, without the risk and potential consequences of X-ray exposure. Preoperative imaging tools like CDU and CTA should be considered part of the gold standard in abdominally based free flap breast reconstruction.

Sub-100-nanometre resolution in total internal reflection fluorescence microscopy.

Combining total internal reflection fluorescence microscopy with structured illumination allows optical wide-field imaging with sub-100-nanometre resolution. We present a novel objective-launch set-up for standing wave illumination that takes advantage of a tunable transmission diffraction grating and transparent phase shifters actuated by electro-active polymers to control the excitation pattern in three dimensions. Image acquisition is completed in less than 1 s. To reconstruct the extended image spectrum, we apply a new apodization function that results in a lateral resolution of 89 nm for green emission wavelength.

Diagnostic pitfalls in postinterventional intraarterial magnetic resonance angiography after recanalization of femoropopliteal arterial occlusions.

BACKGROUND: Magnetic resonance (MR)-guided vascular interventions are of increasing interest, and, with the use of contrast-enhanced techniques, intraarterial contrast-enhanced MR angiography (ia-ce-MRA) competes with intraarterial digital subtraction angiography (ia-DSA) for the diagnostic evaluation of the infrainguinal vessel tree. PURPOSE: To assess the diagnostic value of ia-ce-MRA and high-resolution T1-weighted (hr-T1w) imaging compared to the gold-standard ia-DSA for residual stenosis and local dissections after femoropopliteal recanalization in patients with peripheral arterial occlusive disease (PAOD). MATERIAL AND METHODS: Eight patients with PAOD and short vessel occlusion of their femoropopliteal arteries underwent recanalization and balloon positioning under DSA. Patients were transferred to a short-bore MR scanner. Percutaneous transluminal angioplasty (PTA) was accomplished under MR fluoroscopy. Pre- and postinterventional ia-ce three-dimensional (3D) gradient-echo MRA with gadopentate dimeglumine was performed using the intraarterial introducer sheath. Maximum intensity projections (MIP) and multiplanar reconstructions (MPR) were calculated from the data set. High-resolution T1w images of the angioplasty region before and after dilatation were acquired. Control ia-DSA images were obtained. RESULTS: The postinterventional angioplasty results for stenosis grading were comparable in ia-MRA and ia-DSA. Only two of five local dissections in ia-DSA were visualized with the ia-ce-MRA runs including MIPs and MPRs. To clearly depict dissection, hr-T1w images were needed. CONCLUSION: Grading of stenotic lesions with ia-ce-MRA after PTA is comparable to ia-DSA. Intraarterial ce-MRA with calculated MIPs and MPRs is only partially sufficient to visualize local dissections after PTA. High-resolution T1w images are required for precise diagnosis of dissections in magnetic resonance tomography.

Intraoperative color duplex ultrasound during renal transplantation.

The purpose of this pictorial essay is to describe the role of intraoperative color duplex ultrasound in detecting vascular complications during renal transplantation. Intraoperative color duplex scanning during renal transplantation detects vascular complications noninvasively. Reasons for disturbed perfusion can be malposition or external compression, intravascular thrombi, vessel wall dissection and vasospasm. Color duplex ultrasound is a useful procedure in selected conditions with an intraoperatively suspected perfusion problem during renal transplantation.

Long-term outcomes of elderly patients with CYP2C9 and VKORC1 variants treated with vitamin K antagonists.

Essentials The long-term effects of VKORC1 and CYP2C9 variants on clinical outcomes remains unclear. We followed 774 patients ≥65 years with venous thromboembolism for a median duration of 30 months. Patients with CYP2C9 variants are at increased risk of death and non-major bleeding. Patients with genetic variants have a slightly lower anticoagulation quality only. SUMMARY: Background The long-term effect of polymorphisms of the vitamin K-epoxide reductase (VKORC1) and the cytochrome P450 enzyme gene (CYP2C9) on clinical outcomes remains unclear. Objectives We examined the association between CYP2C9/VKORC1 variants and long-term clinical outcomes in a prospective cohort study of elderly patients treated with vitamin K antagonists for venous thromboembolism (VTE). Methods We followed 774 consecutive patients aged ≥ 65 years with acute VTE from nine Swiss hospitals for a median duration of 30 months. The median duration of initial anticoagulant treatment was 9.4 months. The primary outcome was the time to any clinical event (i.e. the composite endpoint of overall mortality, major and non-major bleeding, and recurrent VTE. Results Overall, 604 (78%) patients had a CYP2C9 or VKORC1 variant. Three hundred and thirty-four patients (43.2%) had any clinical event, 119 (15.4%) died, 100 (12.9%) had major and 167 (21.6%) non-major bleeding, and 100 had (12.9%) recurrent VTE. After adjustment, CYP2C9 (but not VKORC1) variants were associated with any clinical event (hazard ratio [HR], 1.34; 95% confidence interval [CI], 1.08-1.66), death (HR, 1.74; 95% CI, 1.19-2.52) and clinically relevant non-major bleeding (sub-hazard ratio [SHR], 1.39; 95% CI, 1.02-1.89), but not with major bleeding (SHR, 1.03; 95% CI, 0.69-1.55) or recurrent VTE (SHR, 0.95; 95% CI, 0.62-1.44). Patients with genetic variants had a slightly lower anticoagulation quality. Conclusions CYP2C9 was associated with long-term overall mortality and non-major bleeding. Although genetic variants were associated with a slightly lower anticoagulation quality, there was no relationship between genetic variants and major bleeding or VTE recurrence.

Efficient haemodialysis despite complete central venous thrombosis.

Two cases with a fully functional haemodialysis access, in spite of complete thrombotic occlusion of the ipsilateral subclavian and/or brachiocephalic vein are reported. The coincidentally detected complete venous occlusions may indicate that occult venous stenosis or thrombosis is more frequent than generally assumed. In order to avoid deterioration of the haemodynamic situation interventions may be withheld unless clinical problems related to a diminished outflow occur.

Quality of life improvement after hospital- based rehabilitation or home-based physical training in intermittent claudication.

BACKGROUND: The magnitude of potential changes in Quality-of-Life (QoL) after structured institution-based or home-based peripheral arterial disease (PAD) rehabilitation programs are largely unknown at present. This pilot study provides first QoL data after PAD rehabilitation or a home-based PAD training. PATIENTS AND METHODS: In a non-randomized, open-label pilot study three groups of out-patients were compared: group 1 (n = 18) PAD rehabilitation; group 2 (n = 17) PAD rehabilitation + clopidogrel 75 mg once daily; group 3 (n = 20) home-based training. The training period was 3 months, which was followed by a 3-month observation phase (without prescribed training). The institution-based rehabilitation program consisted of 3 training hours per week whereas patients training at home were instructed to walk for 1 hour per day on an outdoor track. QoL assessment was performed using MOS SF-36, PAVK-86 and PAD-WIQ questionnaires. RESULTS: At baseline background variables, demographics and claudication distances were comparable between groups. After three months of training the percentage changes for the initial and the absolute claudication distance (ICD, ACD) for groups 1, 2, and 3 amounted to 164%, 201%, 44% (ICD) and 83%, 131%, 5% (ACD), respectively. Statistically significant QoL improvements were recorded for physical functions, pain and disease related anxiety in all three study groups; statistically significant inter-group differences were not found. CONCLUSIONS: In sharp contrast to the development of the claudication distances the improvement in QoL, found after 3 months of training, was comparable and not consistently different between the groups.

Association between thyroid dysfunction and venous thromboembolism in the elderly: a prospective cohort study.

BACKGROUND: Venous thromboembolism (VTE) and subclinical thyroid dysfunction (SCTD) are both common in elderly patients. SCTD has been related to a hypercoagulable state and an increased thromboembolic risk. However, prospective data on the relationship between SCTD and VTE are lacking. OBJECTIVES: To investigate the relationship between SCTD and recurrent VTE (rVTE), all-cause mortality, and thrombophilic biomarkers. Patients Elderly patients with VTE were studied. METHODS: In a prospective multicenter cohort, thyroid hormones and thrombophilic biomarkers were measured 1 year after acute VTE, as both may be influenced by acute thrombosis. We defined subclinical hypothyroidism (SHypo) as elevated thyroid-stimulating hormone (TSH) levels (4.50-19.99 mIU L(-1) ), and subclinical hyperthyroidism (SHyper) as TSH levels of < 0.45 mIU L(-1) , both with normal free thyroxine levels. Outcomes were incidence of rVTE and overall mortality during follow-up starting after the 1-year blood sampling. RESULTS: Of 561 participants (58% with anticoagulation), 6% had SHypo and 5% had SHyper. After 20.8 months of mean follow-up, 9% developed rVTE and 10% died. The rVTE incidence rate was 7.2 (95% confidence interval [CI] 2.7-19.2) per 100 patient-years in SHypo participants, 0.0 (95% CI 0.0-7.6) in SHyper participants, and 5.9 (95% CI 4.4-7.8) in euthyroid participants. In multivariate analyses, the sub-hazard ratio for rVTE was 0.00 (95% CI 0.00-0.58) in SHyper participants and 1.50 (95% CI 0.52-4.34) in SHypo participants as compared with euthyroid participants, without increased levels of thrombophilic biomarkers. SHyper (hazard ratio [HR] 0.80, 95% CI 0.23-2.81) and SHypo (HR 0.99, 95% CI 0.30-3.29) were not associated with mortality. CONCLUSION: In elderly patients, SHyper may be associated with lower rVTE risks. SHypo showed a non-statistically significant pattern of an association with rVTE, without increased mortality or differences in thrombophilic biomarkers.

Physical activity and risk of bleeding in elderly patients taking anticoagulants.

BACKGROUND: Although the possibility of bleeding during anticoagulant treatment may limit patients from taking part in physical activity, the association between physical activity and anticoagulation-related bleeding is uncertain. OBJECTIVES: To determine whether physical activity is associated with bleeding in elderly patients taking anticoagulants. PATIENTS/METHODS: In a prospective multicenter cohort study of 988 patients aged ≥ 65 years receiving anticoagulants for venous thromboembolism, we assessed patients' self-reported physical activity level. The primary outcome was the time to a first major bleeding, defined as fatal bleeding, symptomatic bleeding in a critical site, or bleeding causing a fall in hemoglobin or leading to transfusions. The secondary outcome was the time to a first clinically relevant non-major bleeding. We examined the association between physical activity level and time to a first bleeding by using competing risk regression, accounting for death as a competing event. We adjusted for known bleeding risk factors and anticoagulation as a time-varying covariate. RESULTS: During a mean follow-up of 22 months, patients with a low, moderate, and high physical activity level had an incidence of major bleeding of 11.6, 6.3, and 3.1 events per 100 patient-years and an incidence of clinically relevant non-major bleeding of 14.0, 10.3, and 7.7 events per 100 patient-years, respectively. A high physical activity level was significantly associated with a lower risk of major bleeding (adjusted sub-hazard ratio 0.40, 95% confidence interval 0.22-0.72). There was no association between physical activity and non-major bleeding. CONCLUSIONS: A high level of physical activity is associated with a decreased risk of major bleeding in elderly patients receiving anticoagulant therapy.