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OBJECTIVES: We aimed to evaluate cardiovascular (CV) risk in patients with idiopathic inflammatory myopathies (IIM) compared with healthy controls (HC) and to assess its association with disease-specific features. METHODS: Ninety IIM patients and 180 age-/sex-matched HC were included. Subjects with a history of CV disease (angina pectoris, myocardial infarction and cerebrovascular/peripheral arterial vascular events) were excluded. All participants were prospectively recruited and underwent examinations of carotid intima-media thickness (CIMT), pulse wave velocity (PWV), ankle-brachial index (ABI), and body composition. The risk of fatal CV events was evaluated by the Systematic COronary Risk Evaluation (SCORE) and its modifications. RESULTS: Compared with HC, IIM patients had a significantly higher prevalence of traditional CV risk factors, carotid artery disease (CARD), abnormal ABI and PWV. After propensity score matching (using traditional CV risk factors), the prevalence of CARD and pathological PWV remained significantly higher in IIM than HC. No significant difference in SCORE was observed. The most unfavourable CV risk profile was observed in patients with necrotizing myopathy, especially in statin-induced anti-HMGCR+ patients. The calculated CV risk scores by SCORE, SCORE2 and SCORE multiplied by the coefficient 1.5 (mSCORE) were reclassified according to CIMT and the presence of carotid plaques. SCORE was demonstrated to be most inaccurate in predicting CV risk in IIM. Age, disease activity, lipid profile, body composition parameters and blood pressure were the most significant predictors of CV risk in IIM patients. CONCLUSION: Significantly higher prevalence of traditional risk factors and subclinical atherosclerosis was observed in IIM patients compared with HC.
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Enfermedades Cardiovasculares , Enfermedades de las Arterias Carótidas , Miositis , Humanos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Grosor Intima-Media Carotídeo , Análisis de la Onda del Pulso , Factores de Riesgo , Miositis/epidemiología , Factores de Riesgo de Enfermedad CardiacaRESUMEN
INTRODUCTION: Atrial fibrillation (AF), with a prevalence of 2%, is the most common cardiac arrhythmia. Catheter ablation (CA) has been documented to be superior to treatment by antiarrhythmic drugs (AADs) in terms of sinus rhythm maintenance. However, in obese patients, substantial weight loss was also associated with AF reduction. So far, no study has compared the modern non-invasive (AADs combined with risk factor modification (RFM)) approach with modern invasive (CA) treatment. The aim of the trial is to compare the efficacy of modern invasive (CA) and non-invasive (AADs with risk factor management) treatment of AF. METHODS AND ANALYSIS: The trial will be a prospective, multicentre, randomised non-inferiority trial. Patients with symptomatic AF and a body mass index >30 will be enrolled and randomised to the CA or RFM arm (RFM+AAD) in a 1:1 ratio. In the CA arm, pulmonary vein isolation (in combination with additional lesion sets in non-paroxysmal patients) will be performed. For patients in the RFM+AAD arm, the aim will be a 10% weight loss over 6-12 months, increased physical fitness and a reduction in alcohol consumption. The primary endpoint will be an episode of AF or regular atrial tachycardia lasting >30 s. The secondary endpoints include AF burden, clinical endpoints associated with AF reoccurrence, changes in the quality of life assessed using dedicated questionnaires, changes in cardiorespiratory fitness and metabolic endpoints. An AF freedom of 65% in the RFM+AAD and of 60% in the CA is expected; therefore, 202 patients will be enrolled to achieve the non-inferiority with 80% power, 5% one-sided alpha and a non-inferiority margin of 12%. ETHICS AND DISSEMINATION: The PRAGUE-25 trial will determine if modern non-invasive AF treatment strategies are non-inferior to CA. The study was approved by the Ethics Committee of the University Hospital Kralovske Vinohrady. Results of the study will be disseminated on scientific conferences and in peer-reviewed scientific journals. After the end of follow-up, data will be available upon request to principal investigator. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04011800).
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Fibrilación Atrial , Ablación por Catéter , Antiarrítmicos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Humanos , Estudios Multicéntricos como Asunto , Estudios Prospectivos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Factores de Riesgo , Resultado del Tratamiento , Pérdida de PesoRESUMEN
Background: Idiopathic inflammatory myopathies (IIM) are associated with systemic inflammation, limited mobility, and glucocorticoid therapy, all of which can lead to metabolism disturbances, atherogenesis, and increased cardiovascular (CV) risk. The aim of this study was to assess the CV risk in IIM patients and healthy controls (HC), and its association with disease-specific features. Methods: Thirty nine patients with IIM (32 females; mean age 56; mean disease duration 4.8 years; dermatomyositis: n = 16, polymyositis: n = 7, immune-mediated necrotizing myopathy: n = 8, anti-synthetase syndrome: n = 8) and 39 age-/sex-matched HC (32 females, mean age 56) without rheumatic diseases were included. In both groups, subjects with a history of CV disease (angina pectoris, myocardial infarction, cerebrovascular, and peripheral arterial vascular events) were excluded. Muscle involvement, disease activity, and tissue damage were evaluated (Manual Muscle Test-8, Myositis Intention to Treat Activity Index, Myositis Damage Index). Comorbidities and current treatment were recorded. All participants underwent examinations of carotid intima-media thickness (CIMT), pulse wave velocity (PWV), ankle-brachial index (ABI), and body composition (by densitometry and bioelectric impedance). The risk of fatal CV events was evaluated by the Systematic COronary Risk Evaluation (SCORE, charts for the European population) and its modifications. Results: Compared to HC, there was no significant difference in IIM patients regarding blood pressure, ABI, PWV, CIMT, and the risk of fatal CV events by SCORE or SCORE2, or subclinical atherosclerosis (CIMT, carotid plaques, ABI, and PWV). The calculated CV risk scores by SCORE, SCORE2, and SCORE multiplied by the coefficient 1.5 (mSCORE) were reclassified according to the results of carotid plaque presence and CIMT; however, none of them was demonstrated to be significantly more accurate. Other significant predictors of CV risk in IIM patients included age, disease duration and activity, systemic inflammation, lipid profile, lean body mass, and blood pressure. Conclusions: No significant differences in CV risk factors between our IIM patients and HC were observed. However, in IIM, CV risk was associated with age, disease duration, duration of glucocorticoid therapy, lipid profile, and body composition. None of the currently available scoring tools (SCORE, SCORE2, mSCORE) used in this study seems more accurate in estimating CV risk in IIM.
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Acute myocardial infarction is a manifestation of atherosclerosis which may be fatal. In-hospital and short-term mortality rates after an acute myocardial infarction have declined in the past few decades. However, although long-term mortality has decreased, it remains unacceptably high. This review paper summarises the non-pharmacological interventions (smoking cessation, physical activity, nutrition, and psychosocial intervention) and pharmacological approaches (antiplatelet and lipid-lowering therapy, renin-angiotensin-aldosterone system inhibitors, beta-blockers, and glucose-lowering drugs) to secondary prevention after a myocardial infarction. The provision of secondary prevention services is established through cardiac rehabilitation, which consists of several discussed components. Finally, we discuss the quality indicators for long-term care after an acute myocardial infarction.
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AIMS: Patients on chronic haemodialysis have a wide range of changes in cardiac function and structure, including left ventricular hypertrophy, dilation and diastolic dysfunction or pulmonary hypertension. All these changes were linked to increased mortality in previous studies. High-flow arteriovenous fistulas (AVF) are supposed to be a factor contributing to their development. This study investigated the early effect of surgical AVF blood flow (Qa) reduction on these changes in patients with or without heart failure changes. METHODS AND RESULTS: Forty-two patients in chronic haemodialysis programme with high-flow AVF (Qa over 1500 mL/min), indicated for surgery for ≥1 of the following indications: 1.manifest heart failure; 2.hand ischemia; 3.advanced structural heart changes detected by echocardiography. The patients underwent echocardiography on selection visit, before blood flow reducing surgery and six weeks thereafter. The Qa reduction led to decrease of left ventricular mass (p = 0.02), end-diastolic volume (p = 0.008), end-diastolic diameter (p = 0.003) and left atrial volume (p = 0.0006). Diastolic function improved. Similarly, right ventricular diameter and right atrial volume decreased (p = 0.000001 and 0.00009, respectively) together with the decrease of estimated pulmonary artery systolic pressure. 81% of patients suffered from pulmonary hypertension prior to surgery, only 36% thereafter. CONCLUSION: The surgical restriction of the hyperkinetic circulation leads to several improvements of heart structure and function, which was linked to higher mortality in other studies. The beneficial effect of Qa reduction is present even in patients without symptoms of heart failure. The contribution of AVF must be considered with structural or functional heart changes.
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Derivación Arteriovenosa Quirúrgica , Insuficiencia Cardíaca , Derivación Arteriovenosa Quirúrgica/efectos adversos , Ecocardiografía , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/terapia , Hemodinámica , Humanos , Diálisis Renal/efectos adversosRESUMEN
AIMS: High-flow arteriovenous fistula (AVF) for haemodialysis leads to profound haemodynamic changes and sometimes to heart failure (HF). Cardiac output (CO) is divided between the AVF and body tissues. The term effective CO (COef) represents the difference between CO and AVF flow volume (Qa) and better characterizes the altered haemodynamics that may result in organ hypoxia. We investigated the effects of Qa reduction on systemic haemodynamics and on brain oxygenation. METHODS AND RESULTS: This is a single-centre interventional study. Twenty-six patients on chronic haemodialysis with high Qa (>1500 mL/min) were indicated for surgical Qa reduction for HF symptoms and/or signs of structural heart disease on echocardiography. The included patients underwent three sets of examinations: at 4 months and then 2 days prior and 6 weeks post-surgical procedure. Clinical status, echocardiographical haemodynamic assessment, Qa, and brain oximetry were recorded. All parameters remained stable from selection to inclusion. After the procedure, Qa decreased from 3.0 ± 1.4 to 1.3 ± 0.5 L/min, P < 0.00001, CO from 7.8 ± 1.9 to 6.6 ± 1.5 L/min, P = 0.0002, but COef increased from 4.6 ± 1.4 to 5.3 ± 1.4 L/min, P = 0.036. Brain tissue oxygen saturation increased from 56 ± 11% to 60 ± 9%, P = 0.001. CONCLUSIONS: Qa reduction led to increased COef. This was explained by a decreased proportion of CO running through the AVF in patients with Qa > 2.0 L/min. These observations were mirrored by higher brain oxygenation and might explain HF symptoms and improved haemodynamics even in asymptomatic high Qa patients.
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Fístula Arteriovenosa , Derivación Arteriovenosa Quirúrgica , Encéfalo/diagnóstico por imagen , Hemodinámica , Humanos , Diálisis RenalRESUMEN
Arterial hypertension is one of the main modifiable risk factors for atherosclerotic cardiovascular disease. The prevalence of hypertension remains high, and its compensation is still unsatisfactory. In most patients, we should try to achieve office blood pressure values below 140/90 mm Hg, and in those who tolerate treatment well, values around 130/80 mm Hg, as soon as possible, ideally within three months of diagnosis. While lifestyle interventions are essential and should not be overlooked, most hypertensive patients cannot avoid pharmacotherapy, primarily using a combination of two or more antihypertensives. Achieving blood pressure targets, which determine the patients prognosis, is still not ideal. Factors on both the physicians side and the patients side contribute to achieving blood pressure targets. The review article offers various approaches to achieving blood pressure targets, such as using fixed combinations.
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Antihipertensivos , Hipertensión , Antihipertensivos/uso terapéutico , Presión Sanguínea , Combinación de Medicamentos , Humanos , Estilo de Vida , Factores de RiesgoRESUMEN
Movement is the basic attribute of life. It is not surprising that the return to regular physical activity is a very effective and cheap means of preventing and treating most non-cummunicable diseases. Therefore, every physician should be able to prescribe a suitable physical activity. The minimum amount of physical activity with proven effects in primary prevention of chronic diseases is relatively low: 150 minutes of moderate physical activity or 75 minutes of high intensity exercise per week or a combination of the two. The simplest and safe way of physical activity is walking (at least 10â¯000 steps/day or 6â¯000 steps/day on top of daily activities). The FITT model is a more sophisticated way of prescribing physical activity that already requires a stress test. Patients at risk of atherosclerosis or with any manifestation of atherosclerosis (patients with coronary artery disease, post-stroke, peripheral artery disease) benefit from exercise as well as patients with chronic heart failure. Physical activity also helps patients with lung disease (COPD, asthma), metabolic diseases (diabetes mellitus, obesity, osteoporosis) and also rheumatologic diseases. Regular exercise improves cognitive function, reduces depression and anxiety, and helps addicted people. Recently, it has been shown that exercise also changes the gut microbiome. One of the mechanisms that contribute to the beneficial effect of exercise is so-called "exercise factors" - myokines. Physical activity, when properly prescribed, is an inexpensive and universal medication with minimal side effects. It is our "home pharmacy" we always have with us.Key words: cancer - cardiovascular diseases - neuropsychiatric diseases - physical activity - type 2 diabetes.
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Ejercicio Físico/fisiología , Femenino , HumanosRESUMEN
OBJECTIVE: Cardiopulmonary fitness depends on daily energy expenditure or the amount of daily exercise. Patients with narcolepsy spent more time being sleepy or asleep than controls; thus we may speculate that they have a lower quantity and quality of physical activity. The aim of the present study was thus to test the hypothesis that exercise tolerance in narcolepsy negatively depends on sleepiness. PATIENTS AND METHODS: The cross-sectional study included 32 patients with narcolepsy with cataplexy, 10 patients with narcolepsy without cataplexy, and 36 age- and gender-matched control subjects, in whom a symptom-limited exercise stress test with expired gas analysis was performed. A linear regression analysis with multivariate models was used with stepwise variable selection. RESULTS: In narcolepsy patients, maximal oxygen uptake (VO2peak) was 30.1 ± 7.5 mL/kg/min, which was lower than 36.0 ± 7.8 mL/kg/min, p = 0.001, in controls and corresponded to 86.4% ± 20.0% of the population norm (VO2peak%) and to a standard deviation (VO2peakSD) of -1.08 ± 1.63 mL/kg/min of the population norm. VO2peak depended primarily on gender (p = 0.007) and on sleepiness (p = 0.046). VO2peak% depended on sleepiness (p = 0.028) and on age (p = 0.039). VO2peakSD depended on the number of cataplexy episodes per month (p = 0.015) and on age (p = 0.030). CONCLUSIONS: Cardiopulmonary fitness in narcolepsy and in narcolepsy without cataplexy is inversely related to the degree of sleepiness and cataplexy episode frequency.
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Cataplejía/fisiopatología , Ejercicio Físico/fisiología , Narcolepsia/fisiopatología , Consumo de Oxígeno , Vigilia/fisiología , Acelerometría , Adolescente , Adulto , Factores de Edad , Anciano , Cataplejía/complicaciones , Cataplejía/tratamiento farmacológico , Estudios Transversales , Prueba de Esfuerzo , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Narcolepsia/complicaciones , Narcolepsia/tratamiento farmacológico , Consumo de Oxígeno/fisiología , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
Familial hypercholesterolemia (FH) is a genetic disorder with well-known genetic transmission and clinical course. Despite great recent progress, FH is still underestimated, under-diagnosed and thus undertreated. Furthermore it represents a significant healthcare challenge as a common risk factor for the premature development of coronary heart disease. The ScreenPro FH Project is an international network project aiming at improving complex care - from timely screening, through diagnosis to up-to-date treatment of familial hypercholesterolemia in Central, Eastern and Southern Europe. An important task for the project is to harmonise and unify diagnostic and therapeutic approaches in participating countries, where the situation differs from country to country. Countries with more experience should serve as a model for countries developing the FH network.Key words: diagnosis - familial hypercholesterolemia - screening - treatment optimization.
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Hiperlipoproteinemia Tipo II/diagnóstico , Anticolesterolemiantes/uso terapéutico , Eliminación de Componentes Sanguíneos , Enfermedad Coronaria/epidemiología , Europa (Continente)/epidemiología , Europa Oriental/epidemiología , Humanos , Hiperlipoproteinemia Tipo II/epidemiología , Hiperlipoproteinemia Tipo II/terapia , Tamizaje Masivo , Factores de RiesgoRESUMEN
INTRODUCTION: Despite great recent progress, familial hypercholesterolemia (FH) is still underestimated, under-diagnosed and thus undertreated worldwide. We have very little information on exact prevalence of patients with FH in the Central, Eastern and Southern Europe (CESE) region. The aim of the study was to describe the epidemiological situation in the CESE region from data available. METHODS: All local leaders of the ScreenPro FH project were asked to provide local data on (a) expert guess of FH prevalence (b) the medical facilities focused on FH already in place (c) the diagnostic criteria used (d) the number of patients already evidenced in local database and (e) the availability of therapeutic options (especially plasma apheresis). RESULTS: With the guess prevalence of FH around 1 : 500, we estimate the overall population of 588â¯363 FH heterozygotes in the CESE region. Only 14â¯108 persons (2.4 %) were depicted in local databases; but the depiction rate varied between 0.1 % and 31.6 %. Only four out of 17 participating countries reported the the LDL apheresis availability. CONCLUSION: Our data point to the large population of heterozygous FH patients in the CESE region but low diagnostic rate. However structures through the ScreenPro FH project are being created and we can hope that the results will appear soon.Key words: diagnosis - epidemiology - familial hypercholesterolemia - screening.
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Hiperlipoproteinemia Tipo II/epidemiología , Bases de Datos Factuales , Europa (Continente)/epidemiología , Europa Oriental/epidemiología , Heterocigoto , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Tamizaje Masivo , PrevalenciaRESUMEN
Context: Catecholamines may contribute to the accumulation of collagen fibers and extracellular matrix in the arterial and myocardial wall due to various mechanisms. Reversibility of this process has not been studied on both structures simultaneously. Objective: To clarify the long-term effect of excess normalization of catecholamines on carotid and myocardial wall changes in patients with pheochromocytoma or functional paraganglioma (PHEO) after tumor removal. Design, Settings, and Patients: Carotid intima-media thickness (IMT) and the left ventricular (LV) mass index were studied in 50 patients with PHEO before tumor removal and 5 years after tumor removal, and in 50 blood pressure- and age-matched essential hypertensive patients before follow-up and after 5 years of follow-up. Main Outcome Measures: Common carotid artery (CCA)-IMT and LV mass indexed to lean body mass (LBM). Results: Elimination of catecholamine excess in the PHEO group resulted in a significant decrease in CCA-IMT and LV mass index from 0.86 ± 0.17 to 0.83 ± 0.18 mm (P < 0.05) and from 3.2 ± 0.9 to 2.9 ± 0.9 g/LBM (P < 0.001), respectively. In contrast, CCA-IMT and LV mass index increased significantly from 0.78 ± 0.14 to 0.81 ± 0.15 mm (P < 0.05) and from 3.1 ± 0.7 to 3.2 ± 0.6 g/LBM (P < 0.05), respectively, in patients with essential hypertension. Conclusion: In patients with PHEO, carotid IMT and LV mass index can significantly regress after tumor removal, in contrast to the impairment of these parameters in essential hypertensive patients during the same long-term period.
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Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Hipertensión/complicaciones , Evaluación de Resultado en la Atención de Salud , Feocromocitoma/cirugía , Remodelación Ventricular , Adulto , Anciano , Hipertensión Esencial , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: The patency of arteriovenous grafts (AVG) for hemodialysis is mostly limited by growing stenoses that lead to decreasing of blood flow, thromboses and finally to access failure. The aim of this study was to find out if detection of any pathology by duplex Doppler ultrasonography (DDU) early after creation of AVG could identify those with lower survival. METHODS: We retrospectively enrolled AVG examined by DDU in our center within 40 days after their creation during the last 10 years. The findings were divided into 4 subgroups: (1a) normal finding, (1b) DDU risk factor (low flow volume, medial calcinosis of the feeding artery, presence of intimal hyperplasia in the venous anastomosis), (2a) non-significant or (2b) significant stenosis. The primary outcome measure was the cumulative survival of people with AVGs, and the secondary was the primary (unassisted) survival. All patients underwent DDU surveillance every 3 months with pre-emptive treatment of significant stenoses. RESULTS: Overall, 340 cases were found; the median follow-up was 565 days. Normal DDU finding had 60% cases, DDU risk factor 18% cases, non-significant stenosis 13% cases and significant stenosis 9% cases. Occurrence of early significant stenosis was associated with high risk of access loss (hazards ratio (HR) 14.73; 95% CI 5.10-42.58; p < 0.0001). Similarly, the presence of a DDU risk factor and of a non-significant stenosis were related to significantly shorter access lifespan (HR 2.86; 95% CI 1.10-7.40; p = 0.03 and HR 2.83; 95% CI 1.12-7.17; p = 0.03, respectively). CONCLUSION: DDU examination of AVG early after their creation can identify those at higher risk and may contribute to individualize the surveillance strategy.
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Derivación Arteriovenosa Quirúrgica , Prótesis Vascular , Oclusión de Injerto Vascular/diagnóstico por imagen , Fallo Renal Crónico/terapia , Neointima/diagnóstico por imagen , Calcificación Vascular/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Implantación de Prótesis Vascular , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Diálisis Renal/métodos , Estudios Retrospectivos , Factores de Riesgo , Ultrasonografía Doppler Dúplex , Adulto JovenRESUMEN
PURPOSE: Patency of mature vascular access for hemodialysis is mostly limited by the growing stenoses leading to acute access thrombosis. The therapy of choice is usually percutaneous balloon angioplasty (PTA). However, PTA injures the vessel wall and subsequent re-stenosis develops faster than de novo stenosis. Therefore, the key is in appropriate timing of PTA procedures--as late as possible but before access thrombosis develops. Ultrasonography combines the morphologic and functional access assessment, but the former is less precise than angiography. The aim of this study was to compare ultrasonographic and angiographic measuring of residual diameter as the additional criterion of significant stenoses used in our center. METHODS: Residual diameter of significant stenoses was measured by B-mode ultrasonography three times in 20 patients. All the patients were indicated for angiography and the residual diameter of the stenoses was re-analyzed by this method. The repeatability of ultrasonographic residual diameter measurements and reproducibility in comparison to angiography were expressed by coefficients of variation (CV). RESULTS: The residual diameter was 1.69 ± 0.05 mm by ultrasound and 1.65 ± 0.59 mm measured by angiography. In the ultrasound repeatability study, CV was 3.17 ± 2.76% and in the reproducibility study CV was 18.0 ± 15.6%. All the stenoses found to be significant by ultrasound were above 65% by angiography and PTA was performed. CONCLUSIONS: Ultrasonographic measurement of the residual diameter is stable in experienced hands and is well comparable to angiography results. These findings advocate residual diameter of 2.0 mm as the strong additional criterion of the significant stenoses, which can also be used in ultrasound surveillance of arteriovenous grafts.
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Angiografía de Substracción Digital , Derivación Arteriovenosa Quirúrgica/efectos adversos , Oclusión de Injerto Vascular/diagnóstico por imagen , Diálisis Renal , Ultrasonografía Doppler Dúplex , Anciano , Angioplastia de Balón , Constricción Patológica , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/terapia , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Ultrasonografía Doppler en ColorRESUMEN
PURPOSE: Arteries continuously respond to changing tissue demands and to hemodynamic conditions by altering their diameter and wall structure. The relatively slow dilatation of the feeding artery of vascular accesses continues at least two years after access creation with a continuous decrease in wall shear rate (WSR), which however, remains highly supra-physiological. The aim of this study was to test the hypothesis that after a longer time period the WSR returns to its baseline value. METHODS: In a cross-sectional study patients with arteriovenous fistulae were classified into four groups according to the access vintage (from new access to accesses older than six years). The WSR, cross-sectional area, and mean circumferential wall stress were measured and compared between groups. RESULTS: WSR decreased from group 1 (fistula < ninety days old) to group 4 (fistulae > six years old) with a concomitant increase in internal diameter. Patients with the oldest access had normal WSR values (compared to the contralateral brachial artery) and the largest internal diameter of the feeding artery. In diabetic patients the absolute values of WSR were higher and internal diameter was lower compared to nondiabetic patients. CONCLUSIONS: Brachial artery WSR is normal in accesses older than six years with an increased internal diameter and wall cross-sectional area as compared to "younger" accesses. This suggests a process of vascular remodeling with an increase in vascular wall mass and normalization of WSR to physiologic values at the price of increased mean cross-sectional wall stress.
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Derivación Arteriovenosa Quirúrgica , Arteria Braquial/fisiopatología , Hemodinámica , Flujo Sanguíneo Regional , Diálisis Renal , Extremidad Superior/irrigación sanguínea , Adaptación Fisiológica , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/patología , Distribución de Chi-Cuadrado , Estudios Transversales , Europa (Continente) , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estrés Mecánico , Factores de Tiempo , UltrasonografíaRESUMEN
BACKGROUND: Vascular accesses (especially polytetrafluoroethylene grafts) with a permanently low flow (Qa <600 ml/min) are prone to thrombosis and thus have short patency. The reason for a permanently low flow is usually medial calcinosis of the inflow artery in diabetics. We retrospectively studied the long-term patency of low-flow grafts with careful ultrasound surveillance and preemptive interventions. METHODS: Twenty subjects with Qa permanently <600 ml/min were included. Ultrasound surveillance was performed every 3 months in addition to classical monitoring techniques. Significant stenosis was strictly defined as the combination of B-mode narrowing >50% + >2-fold peak systolic velocity increase + 1 additional criterion (residual diameter <2.0 mm or flow volume decrease by >20%). Such stenoses were treated by preemptive percutaneous intervention. Primary and secondary patencies were calculated. RESULTS: The primary patency was 357 ± 316 days and the secondary (cumulative) patency was 996 ± 702 days. The number of interventions was 2.09/patient year, but >10 in 6 (33%) subjects. 93 and 80% of grafts were patent 1 and 2 years after access creation, respectively. CONCLUSION: Low-flow accesses undergoing ultrasound surveillance with strict diagnostic criteria and preemptive interventions had patencies similar to accesses with normal Qa in our study. This was enabled by a relatively high rate of interventions.
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Velocidad del Flujo Sanguíneo , Prótesis Vascular/normas , Enfermedades Cardiovasculares/diagnóstico por imagen , Politetrafluoroetileno/normas , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Prótesis Vascular/tendencias , Enfermedades Cardiovasculares/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , UltrasonografíaRESUMEN
BACKGROUND: Vascular access is the lifeline for end-stage renal disease patients needing hemodialysis treatment. For dialysis treatment two needles are placed into the vascular access. Few studies on needle hemodynamics have been published. METHODS: We investigated needle hemodynamics by means of Doppler ultrasonography, both in B-mode and in pulsed Doppler mode. RESULTS: Direct visualization of the needles, turbulence around the arterial needle and blood flow jet from the venous needle are presented. CONCLUSIONS: Ultrasound investigation of the hemodynamics of the dialysis needles is feasible. The extreme blood flow jet through the arterial needle was directed in all patients to the anterior vessel wall.