The impact of endovascular lower-limb revascularisation on the aortic augmentation index in patients with peripheral arterial disease.

OBJECTIVES: The aortic augmentation index (AIx), a marker of arterial stiffness, and peripheral arterial disease (PAD) are associated with an increased cardiovascular risk. In claudicants, the effect of balloon angioplasty (percutaneous transluminal angioplasty, PTA) on AIx has not been determined so far. METHODS: Measurements of the ankle-brachial pressure index (ABI) and AIx were performed before and 3 months after PTA and compared to age- and sex-matched PAD patients under best medical treatment. RESULTS: The data of 61 patients (44% female, mean age 68 years) who underwent lower-limb PTA was compared to 48 conservatively treated patients (38% female, mean age 68 years). ABI significantly improved after PTA from 0.73 ± 0.02 to 0.85 ± 0.03 (p = 0.001), but remained unchanged in the control group (0.85 ± 0.23 and 0.80 ± 0.21; p = 0.16). Revascularisation was associated with a significant reduction of AIx from 31.5 ± 1.1% to 28.8 ± 1.1% after 3 months (p = 0.01). In the conservatively treated group, AIx did not change during follow-up (29.9 ± 1.1% to 29.9 ± 1.1%; p = 0.83). CONCLUSION: Lower-limb revascularisation in PAD Rutherford stage II-III is associated with an improvement of markers for arterial stiffness.

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.

Cognitive function in patients with peripheral artery disease: a prospective single-center cohort study.

AIM: The aim of the present study was to examine the association between cardiovascular comorbidities and risk factors, and cognitive function in peripheral artery disease (PAD) patients, as well as to determine the influence of cognitive function on cardiovascular outcome in a two-year follow-up. METHODS: The cognitive function of 104 PAD patients was assessed using the mini-mental test (MMSE). Ankle Brachial Index (ABI), Fontaine stage, PAD localization, cardiovascular risk factors and comorbidities were taken from the electronic patient charts. A multiple logistic regression model, which included myocardial infarction (MI), stroke/transient ischemic attack (TIA), diabetes mellitus (DM), coronary heart disease (CHD) and smoking was performed to compare patients with and without cognitive impairment. All study participants were followed for two years in order to evaluate their cardiovascular outcome, mortality and revascularisation rate. RESULTS: There was no significant difference in mini-mental state between asymptomatic and symptomatic PAD patients. ABI and PAD localization was not related to cognitive function. However, pre-existing stroke, TIA, coronary artery disease (CAD) or DM were associated with a lower MMSE score. When MMSE was dichotomized in ≤27 and >27 points, the presence of CAD, history of cerebrovascular events and DM was associated with a MMSE ≤27 in multivariate analysis. There was no association between MMSE and cardiovascular event rate. CONCLUSION: PAD patients with CAD, stroke, TIA or DM have worse cognitive function than those without these factors. There was no evidence that cognitve function influenced cardiovascular outcome.

Free plasma magnesium following glucose loading in healthy humans.

The recognized existence of a circadian pattern in extracellular magnesium balance might mirror either an inherent rhythm in the homeostasis of this ion or dietary factors. Since in vitro insulin enhances cellular magnesium uptake, the circadian rhythm in extracellular magnesium metabolism might be modulated at least in part by carbohydrate intake. To assess this hypothesis, the effects of oral glucose loading on plasma total and ionized magnesium were investigated in lean healthy humans with a negative family history for essential hypertension and diabetes mellitus. Plasma total and ionized magnesium was similar before glucose loading and 30, 60, 90, 180, and 210 min thereafter. It is therefore concluded that in healthy humans the circadian pattern of extracellular magnesium is not modulated by the metabolic and hormonal mechanisms that adjust the concentration of glucose.

Non-invasive pressure measurement of the great saphenous vein in healthy controls and patients with venous insufficiency.

OBJECTIVES: Venous pressure measurement using an intravenous catheter is the sole method for the diagnosis of venous hypertension in patients with chronic venous insufficiency. A noninvasive tool to quantify increased venous pressure is essential for studying venous pathophysiology. Aim of the study was to investigate the value of controlled compression ultrasound (CCU) for noninvasive assessment of venous pressure (VP) of the great saphenous vein (GSV) in healthy persons and patients with venous insufficiency to quantify venous hypertension. METHODS: An optimal visible part of the GSV directly above the ankle was marked on the skin and compressed under ultrasound control and pressure needed for complete compression of the vein was recorded using a pressure manometer with a translucent silicone membrane. Complete insufficiency of the GSV (Hach IV) was documented by duplex ultrasound by an independent investigator before start of the study. VP measurement was performed while normal breathing, deep inspiration and expiration and during a standardized Valsalva maneuver. RESULTS: Twenty controls and 19 patients with complete insufficiency of the GSV were included. Valsalva maneuver induced a slight increase in VP in controls (20.1 ± 4.5 vs 25.1 ± 6.6 mbar) but a significant higher increase in patients from 26 to 37 mbar (IQR 18.5-28.0 vs 31.5-43.0; p < 0.001). CONCLUSION: Noninvasive venous pressure measurement of the great saphenous vein using CCU is feasible and documents an increased pressure during Valsalva maneuver in Hach IV patients compared to healthy controls.

Impact of endovascular treatment of atherosclerotic renal artery stenosis on endothelial function and arterial blood pressure.

AIM: Renovascular disease may cause arterial hypertension and decreases renal function, which both impair endothelial function. Endothelial function, a surrogate marker for cardiovascular risk, can be assessed non-invasively by ultrasound. The aim of this study was to investigate the impact of percutaneous transluminal renal artery angioplasty (PTRA) with stenting on endothelial function and arterial blood pressure in patients with renal artery stenosis (RAS). METHODS: Flow mediated dilatation of the brachial artery, flow velocities and shear stress were measured with high resolution ultrasound in 24 hypertensive patients with renal artery stenosis prior and one day after revascularization by PTRA with stenting. Endothelial-independent brachial dilatation was measured after application of nitroglycerin. RESULTS: Endothelial-dependent dilatation improved from 2.4±0.9% to 6.1±1.4% (P=0.03), whereas endothelial-independent dilatation did not change after PTRA. Endothelial-dependent reactive hyperemic blood flow increased from 195±40 mL/min to 536±94 mL/min (P=0.0008), whereas endothelial-independent hyperemia did not increase after revascularization. After PTRA, shear stress at rest decreased from 37±11 to 23±3 dyne/cm² (P<0.0001), and reactive hyperemic shear stress increased from 89±29 to 107±12 dyne/cm² (P=0.014). The impact of PTRA on arterial blood pressure resulted in a mean decrease of 21±5 mmHg in systolic pressure (P<0.0001), of 9±2 mmHg in diastolic pressure (P=0.03), and of 14±5 mmHg in peripheral pulse pressure (P=0.0003), respectively. CONCLUSION: Endovascular treatment of renovascular disease improves endothelial function and decreases in resting shear stress.

Conditions currently associated with erythema nodosum in Swiss children.

UNLABELLED: A review was made of the 36 paediatric patients in whom the diagnosis of erythema nodosum had been established between 1977 and 1996 at the Department of Paediatrics, University of Bern, Switzerland. Infectious diseases were associated with erythema nodosum in 20 (including 10 streptococcal infections) and non-infectious inflammatory diseases in 8 patients. None of the 36 patients had tuberculosis or had been exposed to sulphonamides, phenytoin or hormonal contraceptives. There were eight patients in whom either the associated disease was not diagnosed, or there was no other disease. CONCLUSION: Most cases of erythema nodosum are nowadays caused by non-mycobacterial infectious diseases or by non-infectious inflammatory diseases.

Free circulating magnesium and renal magnesium handling during acute metabolic acidosis in humans.

Ion-selective electrodes have been designed for determining the ionized concentration of magnesium in blood, the biologically active form of this ion. The effect of acute acidosis induced by ammonium loading on circulating and urinary magnesium was investigated in 11 volunteers. No changes in plasma total and ionized magnesium were noted following administration of ammonium chloride. On the contrary, administration of ammonium chloride increased the plasma free magnesium fraction and the urinary magnesium excretion. The study demonstrates that the hypermagnesiuria induced by acute acidosis is not caused by ionized hypermagnesemia and supports the theory that acidosis decreases the circulating magnesium fraction that is bound to proteins.