RESUMEN
Endovascular aortic aneurysm repair (EVAR) is a widely accepted treatment for anatomically fitted abdominal aortic aneurysms. The increasing use of this procedure has prompted the need for close surveillance and reliable post-operative imaging. The current tool for assessing EVAR technical success is to perform computed tomography angiography (CTA) in order to exclude endoleaks and to confirm the exclusion of the aneurysm sac. Contrast enhanced ultrasound with low mechanical index is a promising method for follow-up of patients after EVAR. It seems to allow better identification and characterization of endoleaks than unenhanced ultrasound and even than CTA for very low flow endoleaks.
Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Medios de Contraste , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía/métodos , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Estudios de Seguimiento , Tereftalatos Polietilenos , Politetrafluoroetileno , Sensibilidad y Especificidad , Stents , Factores de Tiempo , Ultrasonografía Doppler/métodos , Ultrasonografía Doppler en Color/métodosRESUMEN
Usefulness of magnetic resonance angiography in the screening of renal artery stenosis in hypertensive patients: proposition of a diagnostic algorithm: a study on 245 patients. Different non-invasive techniques, including Duplex, spiral angioscan, and magnetic resonance angiography (MRA) are available for the diagnosis of renal artery stenosis (RAS). The aim of this study was to assess the diagnostic performances of MRA and the MRA-Duplex couple in the diagnosis of RAS. Between September 2003 and January 2005, 245 patients benefited from a renal MRA for the assessment of hypertension etiology. The MRA-Duplex couple was performed in 228 patients. Renal arteriography was performed in case of abnormalities observed with MRA and/or Duplex (n=41). The sensitivity and specificity of MRA were respectively at 100% and 23%. The sensitivity was notably higher in the right renal artery (100 vs. 73%). The sensitivity and specificity of Duplex were respectively at 71 and 85%. The concordance between the two exams was disappointing (kappa at 0.39 for the right side and 0.62 for the left side), leading to the interest of the MRA-Duplex association for excluding the presence of RAS (sensitivity and negative predictive value=100%). However, using the MRA-Duplex couple led to a high number of false positive cases, due to MRA, leading to 11 angiograms out of 41 exams, without any significant RAS. In case of suspicion of RAS, the MRA-Duplex couple permits to exclude definitely the diagnosis of RAS. In case of discordance between the 2 exams, it would be useful to require a spiral angioscan and/or redo a Duplex exam using contrast agents, prior to angiography with a therapeutic goal. These management modalities might be useful to avoid the number of normal angiograms, with an inherent risk of complications and cost excess.
Asunto(s)
Algoritmos , Hipertensión Renovascular/etiología , Angiografía por Resonancia Magnética/métodos , Obstrucción de la Arteria Renal/diagnóstico , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
Real-time three-dimensional echocardiography is currently used in a standard echocardiographic examination. Volume-rendered images better identify and locate anatomic structures and improve our comprehensive approach to various heart diseases. The assessment of mitral valve disease and congenital cardiopathies and the measurement of left ventricular mass, volume, and ejection fraction are the three main applications of three-dimensional echocardiography. Three-dimensional vascular imaging is an emerging and promising application of three-dimensional echography. The near future of three-dimensional echography requires the integration of all modalities of conventional echography in three dimensional probes, a higher image resolution compared to the current situation, as well as the development of real-time three-dimensional probes dedicated to transesophageal cardiac or vascular examination.
Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Ecocardiografía Doppler en Color , Ecocardiografía Tridimensional , Cardiopatías Congénitas/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Prolapso de la Válvula Mitral/diagnóstico por imagen , Estenosis de la Válvula Mitral/diagnóstico por imagen , Adulto , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Cateterismo , Arterias Cerebrales/diagnóstico por imagen , Femenino , Predicción , Atrios Cardíacos/diagnóstico por imagen , Neoplasias Cardíacas/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Estenosis de la Válvula Mitral/terapia , Volumen SistólicoRESUMEN
BACKGROUND: Preservation of annuloventricular continuity through the chordae tendinae aims to maintain left ventricular (LV) function and thus improve postoperative prognosis. This study was designed to prospectively investigate the effect of anterior chordal transection on global and regional LV and right ventricular (RV) function in mitral regurgitation (MR). METHODS AND RESULTS: Sixty-five patients with severe MR underwent radionuclide angiography before and after either mitral valve (MV) repair (42 patients) or replacement with anterior chordal transection (23 patients). LV and RV ejection fractions (EF) were determined at rest. Both ventricles were divided into 9 regions to analyze regional EF and the effect of anteromedial translation related to surgery. After surgery there was a significant decrease in LVEF (P=0.038) and an increase in RVEF (P=0.036). However, LVEF did not change after MV repair (63.8+/-9.9% to 62.6+/-10.3%), whereas RVEF improved (40.7+/-10.1% to 44.5+/-8.1%, P=0.027). In contrast, LVEF decreased after MV replacement (61.7+/-10.1% to 57.2+/-9.9%, P=0.03), and RVEF was unchanged (40.9+/-10.9% to 41.3+/-9.1%). LVEF 4 and 5, in the area of anterior papillary muscle insertion, were impaired after MV replacement compared with MV repair (region 4, 77.6+/-16.7% versus 87.7+/-10.8%, P=0.005, and region 5, 73.9+/-19.3% versus 89.9+/-13.1%, P<0.001). Moreover, anterior chordal transection led to a significant impairment in the apicoseptal region of the RV (RVEF 4, 50.3+/-15.6% versus 59.3+/-13.8%, P=0.02). CONCLUSIONS: Anterior chordal transection during MV replacement for MR impairs not only regional LV function but also regional RV function.
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Procedimientos Quirúrgicos Cardíacos/efectos adversos , Cuerdas Tendinosas/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Derecha/etiología , Procedimientos Quirúrgicos Cardíacos/métodos , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/fisiopatología , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/diagnóstico , Insuficiencia de la Válvula Mitral/fisiopatología , Estudios Prospectivos , Angiografía por Radionúclidos , Volumen Sistólico , Tasa de Supervivencia , Resultado del Tratamiento , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/fisiopatologíaRESUMEN
Carotid stenosis is a common cause of ischemic stroke. The management of patients with a carotid lesion is mainly based on the degree of stenosis. Ultrasonography is a reliable and accurate method of quantification of the stenosis. The sonographic quantification is based on both velocity and morphological criteria. B mode, color or power Doppler as well as spectral Doppler are used for this purpose. The actual velocity criteria for a 70% stenosis (NASCET definition) are as follows: maximal systolic velocity above 230 cm.s-1, telediastolic velocity above 100 cm.s-1, carotid ratio above 4. The morphological quantification of the stenosis relies on Doppler imaging and B-mode coupling. With ultrasound, the residual area can be measured using a short axis plane, and the diameter reduction using a longitudinal plane. The different parameters provide complementary information that must be in agreement with one another. There is a growing interest in plaque characterization. Undoubtedly plaque structure and surface appearance also play a role in the individual risk of stroke. Thus, B-mode plaque analysis must be an integral part of the ultrasonographic examination. Transcranial Doppler is a complementary investigation that can be used to evaluate the hemodynamic consequences of the stenosis and to look for intracranial lesions. Optimal sonographic examination currently allows comprehensive evaluation of a carotid lesion.
Asunto(s)
Isquemia Encefálica/terapia , Arterias Carótidas/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Ultrasonografía Doppler Transcraneal , Ultrasonografía Doppler , Disección Aórtica/diagnóstico por imagen , Aterosclerosis/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Isquemia Encefálica/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Arterias Cerebrales/diagnóstico por imagen , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Síndrome del Robo de la Subclavia/diagnóstico por imagenRESUMEN
OBJECTIVE: To compare helical computed tomography angiography with arterial digital subtraction angiography in the diagnosis of renal artery stenoses. METHODS: Fifty hypertensives (24 men; mean age 53 years) were prospectively studied with computed tomography (Somaton Plus S, Siemens) and digital angiography (double-blind evaluation). Computed tomography was performed both in the sequential (the length of the abdomen) and in the helical (6 cm around renal arteries) modes during injection of 120 cm3 contrast medium. RESULTS: Digital angiography visualized 16 significant (< 50% on quantitative angiography) stenoses (16/131 renal arteries, including 32 accessory), in 14 (28%) patients. On helical computed tomography, 16 stenoses were detected, in 49 patients (16/122 renal arteries, seven accessory arteries were not identified because they were located out side the scan area); two patients had false-positive helical computed tomography results. The computed tomography sensitivity, specificity, positive and negative predictive values were 87.5% (14/16), 98.2% (111/114), 87.5% and 98.2%, respectively. In the sequential mode, two cases of bilateral adrenal hyperplasia, two aortic aneurysms and one renal neoplasm were detected. None of these patients had renal artery stenosis. CONCLUSIONS: Helical computed tomography is a suitable new non-invasive diagnostic modality for the detection of renal artery stenosis or adrenal pathology. With continued development and evaluation computed tomography could prove useful as a screening tool or as a replacement for digital angiography in patients with possible secondary hypertension.
Asunto(s)
Hipertensión/diagnóstico por imagen , Obstrucción de la Arteria Renal/diagnóstico por imagen , Arteria Renal/diagnóstico por imagen , Adolescente , Adulto , Anciano , Angiografía de Substracción Digital , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos XRESUMEN
The Ross procedure could provide an ideal aortic valve replacement method in children and young adults. We evaluated midterm echocardiographic results to assess pulmonary homograft function as well as pulmonary autograft dimensions and function. In all, 105 patients (26 women and 79 men) underwent the Ross procedure; median age at implant was 29 years. All patients underwent free root replacement. Transvalvular gradients and autograft dimensions were measured at 3 levels (annulus, sinuses of Valsalva, and proximal aorta) at discharge, at 6 months, and annually thereafter. Perioperative mortality was 4.7%. The mean period for echocardiographic follow-up in 100 patients was 32.7 months (range 0.5 to 7 years), during which 4 noncardiac-related deaths occurred. Two patients underwent late reintervention. No moderate or severe regurgitation was recorded. There was 1 case of mild homograft regurgitation and 4 of mild autograft regurgitation at late follow-up. Autograft peak gradients were low and reproducible (5 +/- 2.8 mm Hg at discharge vs 5.5 +/- 3.5 mm Hg at last follow-up, p = NS). Homograft peak gradients increased significantly without severe obstruction (7.8 +/- 5.7 mm Hg at discharge vs 15.8 +/- 9.2 mm Hg at last follow-up). The diameter of the autograft annulus was stable during follow-up, whereas autograft dimensions at sinuses and proximal aorta increased significantly. One group of patients was identified with sinus diameter increases >20% (group A). The 90 remaining patients were classified into group B. The only parameter significantly different between the 2 groups was the sinus diameters measured at discharge (1.74 cm/m2 (group A) vs 1.92 cm/m2 (group B); p = 0.036). In 100 patients and with echocardiographic follow-up for up to 7 years, the Ross procedure showed excellent results. For 10% of patients, we observed a 20% dilation of sinus diameters, but in only 3 patients (3%) was this beyond the upper normal limit.
Asunto(s)
Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Ecocardiografía , Implantación de Prótesis de Válvulas Cardíacas , Cuidados Posoperatorios/métodos , Adolescente , Adulto , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/mortalidad , Niño , Preescolar , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tasa de Supervivencia , Trasplante Autólogo , Trasplante HomólogoRESUMEN
BACKGROUND AND AIMS OF THE STUDY: In preceding studies, we reported that abnormal Doppler signals of high intensity (HITS) were frequently found in the cerebral arteries of patients with prosthetic mechanical heart valves. These signals should be attributed either to air microbubbles, possibly due to cavitations or to solid emboli elements. On the other hand, the presence of abnormal intracardiac echoes has been reported in patients with mechanical valves. These echoes should be also attributed to air microbubbles or to formed elements. Although in vitro experiments are in favor of the first explanation, the discussion of their origin remains open. METHODS: Among patients subjected to a transesophageal echocardiography (TEE), we selected subjects with mechanical prosthetic heart valves, according to the following criteria: (i) normally functioning valves; (ii) bright echoes suggesting microbubbles, inside the prosthetic valve and/or upstream from it (left ventricular outflow tract or left atrium); (iii) no morphological lesions that could generate solid microemboli at the prosthetic level; (iv) normal carotid arteries, as investigated by color echo-Doppler. RESULTS: Twenty patients were selected: 11 men and nine women of age range 40-64 years. They were implanted with mechanical heart valves (24 Saint-Jude Medical, three Björk-Shiley and one CarboMedics) in the mitral position (10), aortic position (two), or mitral and aortic position (eight) for periods ranging from 10 days to 17 years. There was no major left ventricular dysfunction (mean end-diastolic diameter 51.8 mm; mean ejection fraction 59%). The mean diameter of the left atrium was 46.1 mm. All but three patients were in sinus rhythm; seven had presented with a transient ischemic attack or amaurosis within the six months preceding the investigation. Immediately after TEE, Doppler signals were recorded on the middle cerebral arteries (MCA) during 10 minutes on each side, and the abnormal Doppler signals were counted. Seventeen subjects (85%) exhibited HITS repetition rate from 0.2 to 5.5 per min. CONCLUSION: The percentage of patients with HITS in a non-selected group with mechanical heart valves was about 50%, as observed in previous studies. It appears that in a selected group of patients the percentage with HITS is consistently higher. Therefore, HITS and abnormal intracardiac echoes could have a common origin.
Asunto(s)
Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/cirugía , Prótesis Valvulares Cardíacas , Adulto , Válvula Aórtica , Ecocardiografía Transesofágica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Válvula MitralRESUMEN
In patients with mechanical heart valves (MHVs), transcranial Doppler methods commonly detect high intensity transient signals (HITS) representing microemboli. These microemboli, which are presumably gaseous, may cause stroke and cognitive deterioration. A bovine model was therefore developed for studying the relationship between mitral MHV induced HITS and potential etiogenic factors. We placed an 18 mm, 4 MHz Doppler probe in the brachiocephalic artery to detect MHV induced microbubbles at baseline (rest) and under 9 other conditions. To elucidate the gas composition (CO2 or N2) of the microbubbles, we administered 1%, 3%, and 5% CO2, and 100% O2. To determine effect of the heart rate, we paced the heart at 120, 160, and 180 bpm. To alter the myocardial contractility, we gave dobutamine and esmolol. Two independent, blinded observers counted the HITS from recorded doppler spectra. HITS were defined by an initial unidirectional spectral deviation, a signal power of >8 dB relative to the background power, and lack of a cyclic appearance. The electrocardiogram, aortic and LV pressures, and LV dP/dt were obtained telemetrically. The calves were studied 4 to 6, 8 to 10, and 12 to 14 weeks postoperatively, after which the animals were sacrificed at an approximate 4 month study duration, and a postmortem evaluation of the heart and the main viscera was performed. In all, 27 HITS recordings were made in 10 calves. Myocardial contractility was the only factor to significantly affect HITS frequency; the heart rate and blood gas concentrations had minimal effect on HITS frequency. Our bovine model will be useful for assessing valve designs, as well as the mechanism of HITS, the composition of the microemboli, and their possible pathophysiologic effects on the kidneys and brain.
Asunto(s)
Prótesis Valvulares Cardíacas/efectos adversos , Embolia Intracraneal/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal/métodos , Glándulas Suprarrenales/irrigación sanguínea , Animales , Análisis de los Gases de la Sangre , Bovinos , Circulación Cerebrovascular/fisiología , Modelos Animales de Enfermedad , Frecuencia Cardíaca , Enfermedades de las Válvulas Cardíacas/complicaciones , Enfermedades de las Válvulas Cardíacas/cirugía , Embolia Intracraneal/etiología , Riñón/irrigación sanguínea , Contracción Miocárdica , Circulación Renal/fisiología , Ultrasonografía Doppler Transcraneal/instrumentaciónRESUMEN
BACKGROUND: Few studies have compared sensitivities of ankle-to-brachial index (ABI) and transcutaneous oxygen tension (TcPO2) in a large group of patients with Leriche stage II intermittent claudication. METHOD AND RESULTS: 111 patients (138 limbs) with a stable chronic (> three months) intermittent claudication and significant peripheral vascular disease (PVD) proved by angiography were studied. They performed a treadmill test (10%, 3 km/hr) limited by limb pain. ABI and TcPO2 were measured before, just after exercise, and after three and ten minutes of recovery in supine position. Sensitivities per patient for ABI and TcPO2 were respectively at rest: 82.9% and 28.8%, and after exercise: 88.3% and 62.2%. Sensitivities per leg (n = 138) for ABI and TcPO2 were respectively at rest: 73.9% and 26.8%, and after exercise: 82.6% and 34%. The sensitivity of TcPO2 increased to 56.5% after three minutes of recovery but was always less than that of ABI, which was maximal just after exercise (82.6%). The sensitivity of the regional perfusion index was similar to that of TcPO2. The sensitivity of TcPO2 increased with respect to the Leriche stage and the number of lesions but was always lower than that of ABI. There was a weak correlation between TcPO2 and ABI after exercise, but no correlation was noted between maximal walking distance, ABI, and TcPO2. CONCLUSION: TcPO2 is not required in patients with Leriche stage II intermittent claudication but might be useful either in severely affected patients (Leriche stage III or IV) or in selected patients.
Asunto(s)
Presión Sanguínea , Ejercicio Físico/fisiología , Claudicación Intermitente/diagnóstico , Oxígeno/sangre , Descanso/fisiología , Anciano , Análisis de Varianza , Tobillo , Monitoreo de Gas Sanguíneo Transcutáneo/estadística & datos numéricos , Arteria Braquial , Enfermedad Crónica , Femenino , Humanos , Claudicación Intermitente/sangre , Claudicación Intermitente/fisiopatología , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
Microemboli caused by mechanical heart valves have the potential to cause cerebrovascular events. We investigated the effects of myocardial contractility and heart rate on microemboli production in association with conventional and experimental mechanical heart valves implanted in the mitral position in a bovine model. In 10 calves, the mitral valves were replaced with mechanical valves. Doppler recordings were analyzed for high-intensity transient signals, which are ultrasound reflections from circulating microemboli. The animals were studied at rest, during pacing at 160 bpm, after dobutamine infusion, and after esmolol infusion. The incidence of high intensity transient signals was expressed as signal frequency (signals per hour) and as signal rate (signals per 100 heart cycles). With a 68% increase in the heart rate, signal frequency increased by 135%, but signal rate increased by only 41 %. With a 144% increase in myocardial contractility, signal rate increased by 264 %. With a 31 % decrease in contractility, signal rate decreased by 62 %. We conclude that microemboli production by mechanical heart valves varies with myocardial contractility and heart rate. The fact that contractility affects the incidence of high-intensity transient signals suggests that the microemboli are gaseous in nature, that their production is pressure driven, and that cavitation is a possible cause. It is likely that mechanical heart valve design is responsible for the quantity of microemboli production.
Asunto(s)
Embolia/fisiopatología , Prótesis Valvulares Cardíacas/efectos adversos , Contracción Miocárdica , Agonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/farmacología , Animales , Estimulación Cardíaca Artificial , Cardiotónicos/farmacología , Bovinos , Dobutamina/farmacología , Embolia/diagnóstico por imagen , Embolia/etiología , Frecuencia Cardíaca , Válvula Mitral/cirugía , Contracción Miocárdica/efectos de los fármacos , Propanolaminas/farmacología , Ultrasonografía DopplerRESUMEN
A renovascular etiology occurs in 0.2 to 2% of hypertensive patients. Recently, spiral computed tomography (CT) has evolved as a new minimally invasive tool for the diagnosis of vascular pathologic conditions. The purpose of this study was to compare both spiral CT and color Doppler ultrasonography (US) with intraarterial digital subtraction angiography (DA) in the detection of renal artery stenosis (RAS) in hypertensive patients. Between December 1993 and April 1994, 44 hypertensives (men 22, mean age 52 years) suspected secondary hypertension were prospectively studied with spiral CT (Somatom Plus S, Siemens) US (Acuson, 3.5 MHz probe) and DA (double-blind evaluation). DA visualized 11 significant (> 50%) stenoses (11/114 renal arteries, including 27 accessory). On spiral CT, 9/11 were detected and 2 additional stenoses considered false positive. On US 5 stenoses were detected whereas 11 were demonstrated by DA; 2 patients had false positive US results. [table: see text] We conclude that combined spiral CT and color Doppler ultrasonography is an effective and relatively non invasive alternative to intraarterial digital angiography for the detection of renal artery stenosis in a hypertensive population screened for renovascular hypertension.
Asunto(s)
Hipertensión Renovascular , Obstrucción de la Arteria Renal/diagnóstico por imagen , Arteria Renal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Doppler en Color , Adolescente , Adulto , Anciano , Femenino , Humanos , Hipertensión Renovascular/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
The aim of the study was to evaluate the clinical results of percutaneous transluminal renal angioplasty in a population of 113 consecutive hypertensive patients who underwent endoluminal revascularization for angiographically significant renal artery stenosis. Retrospective analysis of the case records of 104 patients showed that systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased significantly 6 months after angioplasty (-20.9 mmHg and -8.4 mmHg respectively; p = 0.0001). This decrease was maintained until 19.8 months after the procedure. In cases with suboptimal revascularization (persistence of a residual stenosis more than 30%), only the SBP decreased significantly at 6 months (from 177 mmHg to 156.1 mmHg; p = 0.0061); when DBP decreased from 91.4 mmHg to 86.1 mmHg (NS) at 6 months, and fell to 80.9 mmHg (p = 0.026) at 19.8 months (after the performance of a second transluminal angioplasty for 41% patients of this group due to restenosis). Twenty-nine patients presented a restenosis of the renal artery 6 months after the initial procedure. In this group, only SBP decreased significantly at 6.1 months and at 18.7 months (from 171.9 mmHg to 156.1 mmHg and 146.5 mmHg respectively; p = 0.0064 and p = 0.0001). DBP decreased significantly only at 18.7 months (-12.6 mmHg; p = 0.0001), after a second renal angioplasty in 23 patients (79%). In the 60 patients without restenosis at 6 months, SBP and DBP decreased significantly at 6.1 and 18.7 months. No significant variation of creatinine levels was observed. These results confirm the utility of percutaneous transluminal renal angioplasty for the treatment of renovascular hypertension.
Asunto(s)
Angioplastia de Balón , Hipertensión Renovascular/terapia , Obstrucción de la Arteria Renal/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios RetrospectivosRESUMEN
Six young males, in semi-nude conditions, resting in dorsal reclining position, were exposed successively to a thermoneutral environment (30 min), a cold environment (1 degree C) (Cold) or thermoneutrality (Control) (120 min), and during 60 min recovery in thermoneutral conditions. Cardiac output has been measured using a Dual Beam Doppler. During cold stress a significant increase of heart rate (66.4 +/- 6.4 to 91.0 +/- 14.9 beats.min-1), systolic blood pressure (119.5 +/- 7.8 to 218.7 +/- 18.7 mmHg), diastolic blood pressure (68.1 +/- 11.7 to 114.3 +/- 28.3 mmHg) and cardiac output (5.42 +/- 0.96 to 8.08 +/- 1.28 l.min-1) were observed. On the contrary initial systolic aorta flow acceleration is significantly lowered (1130 +/- 120 to 840 +/- 170 cm.s-2). Systolic ejection volume remained unchanged throughout the whole experiment. Increase in cardiac output during cold air (1 degree C) exposure is thus only imputed to the higher heart rate partly due to hypersecretion of catecholamines. The diminution of the blood flow acceleration could be related to a lesser arterial compliance and/or to the cold induced hemoconcentration. Enhanced heart's mechanical work due to sympathetic stimulation, seems thus to be absorbed by the increase in the peripheral resistance.
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Gasto Cardíaco/fisiología , Frío , Descanso , Adulto , Metabolismo Basal , Presión Sanguínea/fisiología , Temperatura Corporal , Exposición a Riesgos Ambientales , Frecuencia Cardíaca/fisiología , Hemodinámica/fisiología , Humanos , Masculino , Respiración/fisiologíaRESUMEN
The intracardiac hemodynamic responses to short periods of 70 degrees head-down and head-up tilts were studied in 12 normal male subjects, ages 19-24 years. Echo-Doppler techniques were used to measure the transmitral and transaortic flow velocities as well as cardiac index, and to evaluate the peripheral impedance. Head-down tilt (HDT) rapidly induced an increase (9.7%, p < 0.05) in the early passive filling of the left ventricle (ME peak of the transmitral flow velocity curve) and in transaortic flow velocity (8%, p < 0.05), as well as in cardiac output (6%, p < 0.05). In spite of a peripheral vasodilation, the blood pressure increased (7%, p < 0.05 for the systolic; 15%, p < 0.01 for the diastolic) and remained at a high level for the 5 min of the experiment. Head-up tilt (HUT) induced inverse responses; i.e., a large initial decrease in the transmitral (-15%, p < 0.05) and transaortic (-16%, p < 0.001) flows. The shape of the arterial peripheral flow indicated an increased vascular impedance. After a short drop, the blood pressure rapidly recovered a level statistically close to that of the pretest. In both cases, tachycardia occurred. We conclude that, in man, the cardiac responses to the changes in posture appear to be related more to the passive changes in ventricular filling due to the blood shift than to the nervous regulation by the arterial baroreflexes, whereas these reflexes mainly act in the control of the vascular impedance.
Asunto(s)
Corazón/fisiología , Hemodinámica/fisiología , Postura , Adulto , Velocidad del Flujo Sanguíneo , Ecocardiografía Doppler , Humanos , Masculino , Factores de TiempoRESUMEN
Several studies have shown that estrogen replacement therapy protects postmenopausal women against coronary artery disease. This protective effect has been ascribed to the hormone's effect on serum lipids, as well as a direct action on the vascular wall. Concurrent administration of a progestin to protect women from the risk of endometrial hyperplasia may alter the protective effects of estrogen. The aim of this study was to assess the evolution of the endothelial function in postmenopausal women given a sequential combination of oral 2 mg estradiol valerate for 11 days, followed by 2 mg estradiol valerate associated with 1 mg cyproterone acetate for ten days (Climène). Each 21-day sequence was followed by a seven-day treatment-free interval. The women received a three-month treatment course. Thirty-one healthy postmenopausal women participated in the study (median age: 51 years; range: 45-59 years). Flow-mediated dilatation (FMD), a reflection of endothelium-dependent vasomotor function, increased from 8.47% at baseline (range: 4.57-11.02%) to 9.64% (range: 7.07-13.12%) at the end of the first treatment cycle; i.e., a 15% increase over baseline (P < 0.0001). FMD further increased after three treatment cycles to 10.59% (range: 8.09-15.22%); i.e., a 28.6% increase over baseline (P < 0.0001). FMD at the end of the first combined sequence or after the 11 days of estradiol only were similar (delta = 0.25%; range: -2.31-5.81%; not significant). In conclusion, in postmenopausal women, a three-month sequential treatment combining estradiol valerate and estradiol valerate plus cyproterone acetate (Climène) has beneficial effects on endothelial function as demonstrated by the evolution of the FMD. There was no decrease in the effect of estradiol on FMD when cyproterone acetate was added to estradiol.
Asunto(s)
Acetato de Ciproterona/administración & dosificación , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiología , Estradiol/análogos & derivados , Estradiol/administración & dosificación , Posmenopausia , Congéneres de la Progesterona/administración & dosificación , Arterias/efectos de los fármacos , Arterias/fisiología , Acetato de Ciproterona/uso terapéutico , Estradiol/uso terapéutico , Terapia de Reemplazo de Estrógeno , Estrógenos Conjugados (USP)/administración & dosificación , Estrógenos Conjugados (USP)/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Congéneres de la Progesterona/uso terapéutico , VasodilataciónRESUMEN
Stroke is a frequent and severe disorder. Most strokes are ischemic in nature and 20% are due to atherosclerosis of the cerebral arteries. Sonographic examination plays a key role in the diagnosis and management of patients with cerebrovascular disease. However, shortcomings can be encountered in the ultrasound evaluation of cervical and intracranial arteries. Contrast agents are known to improve the signal / noise ratio and they can therefore compensate for these shortcomings in most cases. They have proved to be helpful in unfavorable examinations in daily practice. Moreover, their use increases the accuracy and the potential of the technique especially in the intra-cranial examination, increasing the role of ultrasound techniques.
Asunto(s)
Arterias Cerebrales/diagnóstico por imagen , Medios de Contraste , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Humanos , Ultrasonografía Doppler TranscranealRESUMEN
Endovascular treatment of carotid arteries stenoses is an acceptable therapeutic option to surgery in some selected patients. In this case report a patient successfully underwent carotid stenting in the presence of a severe restenosis following a surgical endarterectomy.
Asunto(s)
Angioplastia , Prótesis Vascular , Estenosis Carotídea/terapia , Endarterectomía Carotidea , Anciano , Arteria Carótida Interna , Femenino , Humanos , Recurrencia , Insuficiencia del TratamientoRESUMEN
This case report highlights the complementarity of noninvasive imaging modalities in the diagnosis of extracranial cerebral arteries lesions. The need for a strategy in the treatment of patients with combined lesions is discussed.
Asunto(s)
Arteriosclerosis/diagnóstico , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedad de la Arteria Coronaria/diagnóstico , Anciano , Humanos , MasculinoRESUMEN
PURPOSE: Ultrasonographic follow up of patients with supra-aortic arteries angioplasty and stenting was performed to determine the normal characteristics and to detect restenosis or thrombosis at the repair site. MATERIAL AND METHODS: Twenty-eight patients were followed. The delay between the procedure and the ultrasonographic examination was 1 to 5 years. There were 32 procedures: 7 carotid angioplasties with stenting; 32 vertebral angioplasties (2 stentings), 2 brachiocephalic artery angioplasties (1 stenting); 1 subclavian artery angioplasty. The ultrasonographic examination included morphological and bilateral flow analysis. The usual criteria were measured. Special attention has been given to the morphological aspect of the stents. RESULTS: All of the carotid stents were patent. No restenosis appeared during the follow up. A parietal thickening was observed in one patient without significant reduction of the arterial lumen. There were one vertebral and one brachiocephalic stent thrombosis. The results of the ultrasonographic examinations correlated well with magnetic resonance imaging. CONCLUSION: The ultrasonographic follow up of supra aortic arteries angioplasty and stenting is feasible. An early examination is recommended after the vascular procedure to control the efficacy of the repair and to detect and quantify the residual lesions. This phase is compulsory for an optimal long term follow up.