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排序方式: 共有1309条查询结果,搜索用时 15 毫秒
101.
Initial human experience with the Amplatzer perimembranous ventricular septal occluder device. 总被引:53,自引:0,他引:53
John L Bass G S Kalra Ramesh Arora Jozef Masura Pavlo Gavora Basil D Thanopoulos William Torres Horst Sievert Mario Carminati Gunther Fischer Peter Ewert 《Catheterization and cardiovascular interventions》2003,58(2):238-245
Transcatheter closure of perimembranous ventricular septal defects with coils or devices designed to close other lesions may be complicated by embolization or aortic insufficiency. A new asymmetric Amplatzer perimembranous ventricular septal occluder and delivery system was specifically designed for perimembranous defects. This report describes the first use of this device in 27 patients. Implantation was successful in 25 (93%), with 1 removed for device-related aortic insufficiency and inability to position the delivery sheath in another. Device orientation was excellent when the device was initially advanced through a standard delivery sheath positioned in the left ventricular apex. Twenty-three had complete occlusion within 1 week (92%), with a tiny (< 2 mm) residual shunt in the other two. In the 25 subjects with the device left in place, device-related aortic or tricuspid insufficiency, arrhythmias, and embolization were not observed. These excellent acute results need to be confirmed by long-term follow-up. 相似文献
102.
Ductus venosus waveform analysis has become increasingly affected by technical errors; however, these errors could be avoided if more attention was paid during sampling and analysis. The most common misevaluations include incorrect tracing, under- or overestimation of the peak systolic velocity, overestimation of the end-diastolic velocity, and, as a consequence, incorrect calculation of the pulsatility index facilitated either by human or software error. This article proposes practical suggestions to avoid technical errors in ductus venosus waveform analysis. 相似文献
103.
Bernard De Bruyne Ganesh Manoharan Nico H J Pijls Katia Verhamme Juraj Madaric Jozef Bartunek Marc Vanderheyden Guy R Heyndrickx 《Journal of the American College of Cardiology》2006,48(9):1851-1855
OBJECTIVES: The purpose of this study was to define "significant" renal artery stenosis (i.e., a stenosis able to induce arterial hypertension). BACKGROUND: The degree of renal artery stenosis that justifies an attempt at revascularization is unknown. METHODS: In 15 patients, transstenotic pressure measurements were obtained before and after unilateral stenting. After stenting, graded stenoses were created in the stented segment by progressive inflation of a balloon catheter. Stenosis severity was expressed as the ratio of distal pressure (P(d)) corrected for aortic pressure (P(a)). Balloon inflation pressure was adjusted to create 6 degrees of stenosis (P(d)/P(a) from 1.0 to 0.5, each step during 10 min). Plasma renin concentration was measured at the end of each step in the aorta and in both renal veins. RESULTS: For a P(d)/P(a) ratio >0.90, no significant change in plasma renin concentration was observed. However, when P(d)/P(a) became <0.90, a significant increase in renin was observed in the renal vein of the stenotic kidney, finally reaching a maximal increase of 346 +/- 145% for P(d)/P(a) of 0.50 (p = 0.006). These values returned to baseline when the stenosis was relieved. In addition, plasma renin concentration increased significantly in the vein from the non-stenotic kidney (p = 0.02). CONCLUSIONS: In renal artery stenoses, a P(d)/P(a) ratio of 0.90 can be considered a threshold value below which the stenosis is likely responsible for an up-regulation of renin production and, thus, for renovascular hypertension. These findings might contribute to better patient selection for renal angioplasty. 相似文献
104.
Marc Vanderheyden Tine De Backer Maximo Rivero-Ayerza Peter Geelen Jozef Bartunek Sofie Verstreken Mark De Zutter Marc Goethals 《Heart rhythm》2005,2(10):1066-1072
BACKGROUND: The aim of cardiac resynchronization therapy is correction of left ventricular (LV) dyssynchrony. However, little is known about the optimal timing of LV and right ventricular (RV) stimulation. OBJECTIVES: The purpose of this study was to evaluate the acute hemodynamic effects of biventricular pacing, using a range of interventricular delays in patients with advanced heart failure. METHODS: Twenty patients with dilated ischemic (n = 12) and idiopathic (n = 8) cardiomyopathy (age 66 +/- 6 years, New York Heart Association class III-IV, LV end-diastolic diameter >55 mm, ejection fraction 22% +/- 18%, and QRS 200 +/- 32 ms) were implanted with a biventricular resynchronization device with sequential RV and LV timing (VV) capabilities. Tissue Doppler echocardiographic parameters were measured during sinus rhythm before implantation and following an optimal AV interval with both simultaneous and sequential biventricular pacing. The interventricular interval was modified by advancing the LV stimulus (LV first) or RV stimulus (RV first) up to 60 ms. For each stimulation protocol, standard echocardiographic Doppler and tissue Doppler imaging (TDI) echo were used to measure the LV outflow tract velocity-time integral, LV filling time, intraventricular delay, and interventricular delay. RESULTS: The highest velocity-time integral was found in 12 patients with LV first stimulation, 5 patients with RV first stimulation, and 3 patients with simultaneous biventricular activation. Compared with simultaneous biventricular pacing, the optimized sequential biventricular pacing significantly increased the velocity-time integral (P <.001) and LV filling time (P = .001) and decreased interventricular delay (P = .013) and intraventricular delay (P = .010). The optimal VV interval could not be predicted by any clinical nor echocardiographic parameter. At 6-month follow-up, the incidence of nonresponders was 10%. CONCLUSION: Optimal timing of the interventricular interval results in prolongation of the LV filling time, reduction of interventricular asynchrony, and an increase in stroke volume. In patients with advanced heart failure undergoing cardiac resynchronization therapy, LV hemodynamics may be further improved by optimizing LV-RV delay. 相似文献
105.
Role of tension receptors in dyspeptic patients with hypersensitivity to gastric distention 总被引:6,自引:0,他引:6
BACKGROUND & AIMS: Studies in health have shown that tension-sensitive mechanoreceptors mediate sensitivity to gastric distention. A role for these mechanoreceptors in perception or symptoms in hypersensitive functional dyspepsia (FD) has not been established. Tension-sensitive mechanoreceptors are activated during phasic contractions and inactivated during gastric relaxation. The aim of the present study was to investigate whether hypersensitive FD patients perceive spontaneous changes in fundic wall tension and whether fundus-relaxing drugs decrease sensitivity to gastric distention and meal-related symptoms. METHODS: Fifty patients were selected after a barostat study established gastric hypersensitivity. In 12 patients, an intragastric balloon was inflated with a fixed volume just below perception thresholds and patients were asked to indicate changes in perception on a keypad, and the relationship between perception and contractions was analyzed. In 20 patients, we studied the influence of the fundus-relaxing drug sumatriptan on sensitivity to gastric distention. In, respectively, 10 and 8 patients, we studied the influence of the fundus-relaxing drugs sumatriptan and clonidine on meal-related symptoms. RESULTS: The majority of patients had a statistically significant association between perception and phasic isovolumetric contractions. Pretreatment with sumatriptan increased both pressures and volumes needed to induce first perception and discomfort. Pretreatment with sumatriptan and clonidine both significantly decreased meal-induced symptoms. CONCLUSIONS: Patients with hypersensitivity to gastric distention perceive isovolumetric phasic contractions of the proximal stomach. Fundus-relaxing drugs decrease sensitivity to gastric distention and decrease meal-induced symptoms in these patients. The findings are compatible with involvement of tension mechanoreceptors in symptom generation in hypersensitive FD. 相似文献
106.
Benny Drieghe Juraj Madaric Giovanna Sarno Ganesh Manoharan Jozef Bartunek Guy R Heyndrickx Nico H J Pijls Bernard De Bruyne 《European heart journal》2008,29(4):517-524
AIMS: A ratio of distal renal pressure to aortic pressure (P(d)/P(a)) <0.90 can be considered a threshold for defining a significant renal artery stenosis (RAS). The aim of this study was to compare renal angiography (QRA) and colour duplex ultrasound (CDUS) to pressure measurements in assessing RAS. METHODS AND RESULTS: In 56 RAS, percent diameter stenosis (DS(angio)), minimal luminal diameter (MLD), Doppler-derived peak systolic velocity (PSV), end-diastolic velocity (EDV), and renal-to-aortic ratio (RAR) were obtained and compared with the P(d)/P(a) measured with a 0.014" pressure wire. P(d)/P(a) correlated with angiography- and CDUS-derived parameters. The best correlation was observed with EDV (R = -0.61). To identify stenosis associated with a P(d)/P(a) < 0.90, the diagnostic accuracy of DS(angio) > 50%, MLD < 2 mm, PSV > 180 cm/s, EDV > 90 cm/s and RAR > 3.5 were, respectively, 60%, 77%, 45%, 77% and 79%, yet, with a high proportion of false positives (38%, 15%, 55%, 11% and 15%, respectively) indicating an overestimation of the severity of the RAS by both QRA and CDUS. New cut-off values for QRA- and CDUS-derived indices were proposed. CONCLUSION: Generally accepted QRA and CDUS-derived indices of RAS severity overestimate the actual severity of RAS. This 'overdiagnosis' is likely the main cause of the disappointing results of renal angioplasty for renovascular hypertension. 相似文献
107.
Geert Robaeys Jozef De Bie Marieke C Wichers Liesbeth Bruckers Frederik Nevens Peter Michielsen Marc Van Ranst Frank Buntinx 《World journal of gastroenterology : WJG》2007,13(43)
AIM: To study the predictive value of the vegetativedepressive symptoms of the Zung Depression Rating Scale for the occurrence of depression during treatment with peg-interferon α-2b of chronic hepatitis C (CHC)patients.METHODS: The predictive value of vegetativedepressive symptoms at 4 wk of treatment for the occurrence of a subsequent diagnosis of major depressive disorder (MDD) was studied in CHC patients infected after substance use in a prospective, multicenter treatment trial in Belgium. The presence of vegetative-depressive symptoms was assessed using the Zung Scale before and 4 wk after the start of antiviral treatment.RESULTS: Out of 49 eligible patients, 19 (39%)developed MDD. The area under the ROC curve of the vegetative Zung subscale was 0.73, P = 0.004. The sensitivity at a cut-point of > 15/35 was 95% (95% CI:74-100). The positive predictive value equalled 44% (95%CI: 29-60).CONCLUSION: In this group of Belgian CHC patients infected after substance use, antiviral treatment caused a considerable risk of depression. Seven vegetativedepressive symptoms of the Zung scale at wk 4 of treatment predicted 95% of all emerging depressions, at a price of 56% false positive test results. 相似文献
108.
Regional brain activation during proximal stomach distention in humans: A positron emission tomography study 总被引:7,自引:0,他引:7
Vandenbergh J Dupont P Fischler B Bormans G Persoons P Janssens J Tack J 《Gastroenterology》2005,128(3):564-573
BACKGROUND & AIMS: Hypersensitivity to proximal gastric distention due to abnormal central nervous system processing of visceral stimuli has been suggested as a possible underlying pathophysiologic mechanism in functional dyspepsia. However, the cortical regions activated by distention of the proximal stomach have not been identified. The aim of this study was to investigate regional brain activation during painful and nonpainful proximal gastric distention in humans. METHODS: Positron emission tomography of the brain was performed in 11 healthy volunteers during 4 conditions: (1) no distention and isobaric distention to the individual thresholds for (2) first, (3) marked, and (4) unpleasant sensation. Data were analyzed using statistical parametric mapping. RESULTS: During maximal distention relative to baseline, significant (P corrected <.05) regional brain activation occurred in the left and right gyrus postcentralis (Brodmann area [BA] 43), the left gyrus temporalis superior (BA 38), the right gyrus frontalis inferior (BA 47, orbitofrontal cortex), the right midanterior cingulate gyrus (BA 24), the right anterior insula, and the left cerebellar hemisphere. These areas showed a progressive increase in activation with increasing intensity of the distending stimulus. CONCLUSIONS: We found evidence for a neuronal network processing distention stimuli of the proximal stomach that is overall consistent with the "visceral stimulation network" described in the literature. In addition, we found activation of the orbitofrontal cortex, confirming its role as a convergence zone for processing of food-related stimuli and regulation of hunger, appetite, satiety, and food intake. We found no evidence for a functional neuroanatomic divergence in the processing of noxious and innocuous gastric stimuli. 相似文献
109.
Background For many years in ischemic heart disease, ventricles rather than atria received attention so not much is known about left atrial function in left ventricular ischemia. Objective Our study aimed to evaluate left atrial appendage (LAA) function by means of biplane transesophageal echocardiography in patients ten days after acute coronary syndromes (ACS). Methods The study was performed on 16 adult patients (65.9±9.9 years old) in whom transesophageal echocardiography was done 10 days after ACS. The following left atrial appendage (LAA) planimetric parameters were analyzed: LAA transversal dimension, LAA longitudinal dimension,LAA maximal area, and LAA minimal area. LAA ejection fraction was calculated and analyzed. The following LAA Doppler parameters were analyzed: the peak LAA emptying and the peak LAA filling velocities. The control group consisted of 14 patients (43±14.6 years old) without cardiovascular diseases. Results Both LAA longitudinal dimension and LAA transversal dimension were significantly higher in patients with ACS than in control patients. The same was observed for LAA maximal area. Also LAA ejection fraction was higher in patients with ACS . LAA minimal area did not differ in the patients in either group. LAA peak emptying flow (LAAE) and LAA peak filling flow (LAAF) were significantly higher in patients of the study group than of the control group. Conclusion Our study shows that two weeks after acute coronary syndrome LAA as a reservoir as well as a pump works at a higher level than it does in the control group. (J Geriatr Cardiol 2005; 2(4):198-201) 相似文献
110.
Interleukin 1alpha single-nucleotide polymorphism associated with systemic sclerosis 总被引:2,自引:0,他引:2
OBJECTIVE: In systemic sclerosis (SSc), constitutive expression of the proinflammatory and fibrogenic cytokine interleukin 1alpha (IL-1alpha) by dermal fibroblasts from the affected skin has been observed. We investigated the association of a single-nucleotide polymorphism at position -889 in the IL-1alpha gene in patients with SSc. METHODS: Genotyping of IL-1alpha-889 polymorphism was performed in 46 patients with SSc and in 150 healthy controls by polymerase chain reaction with sequence-specific primers. All subjects were unrelated Slovak Caucasians. RESULTS: In SSc patients, carriers of the IL-1alpha-889 T allele were significantly overrepresented in comparison with controls (63.0% vs 42.0%; p = 0.01, OR 2.3, 95% CI 1.2-4.6). The frequency of the IL-1alpha-889 T allele was increased in SSc patients (38.0%) in comparison with controls (25.7%; p = 0.02). CONCLUSION: The IL-1alpha-889 polymorphism, previously shown to predispose to increased IL-1 protein expression, may be involved in susceptibility to SSc. 相似文献