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排序方式: 共有1094条查询结果,搜索用时 156 毫秒
41.
Snoddy BD Nanda NC Holman WL Kirklin J Chung SM 《Echocardiography (Mount Kisco, N.Y.)》1996,13(2):159-164
In this report, we describe how transesophageal echocardiography was used not only to diagnose incorrect cannula position of a right ventricular assist device in the left atrium through a patent foramen ovale, but also to guide and to confirm correct cannula placement. 相似文献
42.
Voros S Nanda NC Thakur AC Narayan VK Samal AK 《Echocardiography (Mount Kisco, N.Y.)》1999,16(1):35-39
We report the first case of echocardiographically detected Lambl's excrescences on the pulmonary valve in a 72-year-old man who was referred for transesophageal echocardiography as a part of an evaluation for ischemic stroke. A total of four excrescences were noted on the arterial aspect of the pulmonary valve; two of them were on the anterior cusp, one was on the left cusp, and one was on the right cusp. The excrescence on the left cusp was the largest, measuring 5 mm in length. These valvular strands (Lambl's excrescences) represented an incidental finding and were not associated with any disease process. 相似文献
43.
Moursi M Nanda NC Holman W McGiffin D Samal A de Sousa JB 《Echocardiography (Mount Kisco, N.Y.)》1998,15(7):703-707
In this case report, we present the utility of transesophageal echocardiography in the detection of two uncommon complications of left ventricular assist devices: regurgitation of the bioprosthetic valve in the inflow conduit and a tear of a Dacron conduit with hematoma formation and compression of the right ventricular free wall. 相似文献
44.
Baweja G Nanda NC Nekkanti R Dod H Ravi B Fadel A 《Echocardiography (Mount Kisco, N.Y.)》2004,21(1):95-97
We report three-dimensional echocardiographic delineation of a congenital aneurysm of the membranous interventricular septum causing right ventricular outflow tract obstruction in an adult patient. To our knowledge, these findings have not been described before. 相似文献
45.
Reddy VK Nanda S Bandarupalli N Pothineni KR Nanda NC 《Echocardiography (Mount Kisco, N.Y.)》2008,25(6):653-657
We describe a patient with blunt traumatic chest injury in whom three-dimensional transthoracic echocardiography (3DTTE) confirmed the findings of a flail anterior tricuspid valve leaflet and ruptured anterior papillary muscle seen on two-dimensional transthoracic echocardiography, and in addition identified multiple chordae tendinae rupture of the posterior leaflet. Open heart surgery confirmed the findings. The emerging role of 3DTTE in defining the true extent of traumatic tricuspid valvular injury is highlighted . 相似文献
46.
Pothineni KR Wells BJ Hsiung MC Nanda NC Yelamanchili P Suwanjutah T Prasad AN Hansalia S Lin CC Yin WH Young MS 《Echocardiography (Mount Kisco, N.Y.)》2008,25(8):911-917
There is no gold standard for the measurement of pulmonary regurgitation (PR) severity. Two-dimensional (2D) transthoracic echocardiography is most commonly used to quantify PR severity using color Doppler criteria for aortic regurgitation. However, this method is limited by visualization of only one or two dimensions of the proximal PR jet or vena contracta (VC) precluding accurate assessment of its shape or size. This limitation would be expected to be obviated by three-dimensional (3D) transthoracic echocardiography, which could provide a more accurate quantitative assessment of PR severity. This study evaluated 82 adult patients with PR using 2D and 3D. PR VC area by 3D was obtained by planimetry by positioning the cropping plane exactly parallel to the VC, which was viewed en face by cropping of the 3D data set. Regurgitant volumes were calculated by 2D (assuming a circular VC) and by 3D as a product of the VC and velocity time integral obtained by color Doppler-guided conventional Doppler interrogation of the PR jet.The 3D VC area correlated with 2D jet width (JW)/right ventricular outflow tract (RVOT) width (r = 0.71) and 2D VC area (r = 0.79). 3D JW/RVOT width correlated with 2D JW/RVOT (r = 0.87). 3D regurgitant volumes also correlated with 2D regurgitant volumes (r = 0.76). The 3D VC values of <0.20, 0.20-0.45, 0.46-1.15, and >1.15 cm(2) and regurgitant volumes of <15 ml, 15-50 ml, 51-115 ml, and >115 ml were effective as cutoffs for grades 1, 2, 3, and 4 PR, respectively. In conclusion, quantification of 3D VC area and regurgitant volumes correlate reasonably well with the current 2D methods for measurement of PR. Since 3D visualizes PR VC in three dimensions, it would be expected to provide a more accurate and more quantitative assessment of PR severity as compared to 2D. 相似文献
47.
Bhausaheb Bagal Arun Chandrasekharan Aliya Chougle Navin Khattry 《Hematology/oncology and stem cell therapy》2018,11(1):47-51
Objective/background
Hepatic veno-occlusive disease (VOD) is well recognized potentially serious regimen-related toxicity seen after stem cell transplantation. Severe VOD is associated with poor long-term outcomes with very high mortality. Besides supportive care, only defibrotide has been found to be effective in the management of VOD. The recommended dose of defibrotide is 25 mg/kg/d but there has been no classical dose finding study done for this drug. A higher dose of defibrotide is associated with increased risk of bleeding and this drug is prohibitively expensive. We report our experience of using fixed low dose of defibrotide in patients with VOD.Methods
We retrospectively evaluated 511 patients who underwent stem cell transplant at our center from November 2007 and December 2015. All patients received ursodeoxycholic acid as VOD prophylaxis. Modified Seattle criterion was used for diagnosis and severity grading of VOD. Patients developing VOD were initially treated with furosemide and adequate analgesia. Defibrotide was started within 12 to 24 hours of diagnosis of VOD. All adult patients received defibrotide at a fixed dose of 200 mg twice daily while two children were given dose of 100 mg and 50 mg twice daily.Results
Nine (1.7%) of our patients developed VOD. Daily dose of defibrotide ranged from 5 mg/kg/d to 20 mg/kg/d till resolution of VOD. All patients had complete resolution of VOD. None of our patients required ventilator support or dialysis. No episodes of bleeding were observed. No dose response relationship was observed between defibrotide dose and time to resolution of VOD.Conclusion
Low fixed dose defibrotide initiated early seems to be effective and safe in treatment of VOD. This is relevant in a resource limited setting and warrants prospective evaluation. 相似文献48.
Left ventricular function was analyzed using standard echocardiographic techniques in 26 chronic asymptomatic alcoholics without clinical evidence of cardiovascular disease. All were studied following a long period of abstinence (mean 3.1 years; range 3 months to 17 years). Seven asymptomatic children (mean age 14.1 years; range 4 to 19 years) whose mothers had been actively drinking throughout their pregnancies were also studied. The calculated fractional shortening of the left ventricle (per cent ΔS), ejection fraction, mean velocity of circumferential fiber shortening (mean VCF), excursions and maximal systolic velocites of the ventricular septum and left ventricular posterior wall, preejection period/left ventricular ejection time ratios, mitral valve EF slopes, and thicknesses of the left ventricular posterior wall and ventricular septum were obtained in all. Normal left ventricular function was found in all but one adult alcoholic. In this patient, the per cent ΔS, ejection fraction, and mean VCF were reduced. One additional adult alcoholic had a minimally thickened ventricular septum. Our results differ from other studies which have shown significant left ventricular dysfunction in asymptomatic chronic alcoholics. A possible explanation is the much longer period of abstinence of our chronic alcoholics at the time of their examinations. It also appears that left ventricular function in children born of alcoholic mothers is not affected when assessed after the long interval following prolonged exposure to alcohol in utero. 相似文献
49.
50.
Rajagopalan N Simon MA Shah H Mathier MA López-Candales A 《Echocardiography (Mount Kisco, N.Y.)》2008,25(7):706-711
Objectives: The objective of this study was to correlate tissue Doppler imaging of the right ventricle (RV) with pulmonary hemodynamics in patients referred for right heart catheterization. Methods: Seventy subjects (mean age 54 ± 13; 35 males) prospectively underwent tissue Doppler imaging of the RV and right heart catheterization within 1 day of each other. Peak systolic velocity and strain were measured at the RV free wall and correlated with pulmonary hemodynamics. Results: RV myocardial velocity demonstrated no correlation with any hemodynamic variable. While RV strain demonstrated significant correlation with cardiac index (r =−0.61; P < 0.001), correlations with transpulmonary gradient (r = 0.26; P < 0.05) and pulmonary vascular resistance (r = 0.30; P < 0.05) were weaker. Subgroup analysis revealed that in patients with left ventricular systolic dysfunction (n = 31), RV strain showed no correlation with any hemodynamic variable. In patients with normal left ventricular systolic function (n = 39), correlations were significant between RV strain and mean pulmonary artery pressure (r = 0.59; P < 0.001), pulmonary vascular resistance (r = 0.60; P < 0.001), and cardiac index (r =−0.67; P < 0.001). Conclusions: RV myocardial strain correlates significantly with pulmonary hemodynamics in patients with pulmonary hypertension and normal left ventricular function. However, there is no correlation with RV performance in patients with left ventricular dysfunction. 相似文献