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141.
142.
Marwin Bannehr Ulrike Kahn Josephin Liebchen Maki Okamoto Valentin Hähnel Christian Georgi Victoria Dworok Christoph Edlinger Michael Lichtenauer Tanja Kücken Siegfried Kropf Anja Haase-Fielitz Christian Butter 《The Canadian journal of cardiology》2021,37(7):1086-1093
BackgroundFunctional tricuspid regurgitation (TR) is a frequent finding in echocardiography. Despite general consent that right ventricular (RV) dysfunction impacts outcome of patients with TR, it is still unknown which echocardiographic parameters most accurately reflect prognosis. In this study we aimed to evaluate the prevalence of RV dysfunction and its prognostic value in patients with TR.MethodsData from 1089 consecutive patients were analysed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change, and right ventricular free wall longitudinal strain (RV strain) were used to define RV dysfunction. Patients were followed for 2-year all-cause mortality. For prediction of survival, reclassification and C statistics of RV functional parameters using TR grade as reference model were performed.ResultsAmong the patients studied, 13.9% showed no TR, 61.2% had mild TR, 19.6% had moderate TR, and 5.3% had severe TR. The TR grade was associated with increased mortality (log rank, P < 0.001). Impaired RV strain and TAPSE were independent predictors for mortality (RV: hazard ratio [HR], 1.130; 95% confidence interval [CI], 1.099-1.160; P < 0.001; TAPSE: HR, 1.131; 95% CI, 1.085-1.175; P < 0.001). Both RV strain and TAPSE improved the reference model for survival prediction (RV: integrated discrimination improvement [IDI], 0.184; 95% CI, 0.146-0.221; P < 0.001; TAPSE: IDI, 0.057; 95% CI, 0.037-0.077; P < 0.001).ConclusionsEchocardiographic evaluation of RV function appears to useful for patients with TR. Assessment of RV strain provides additional value for prediction of 2-year mortality. 相似文献
143.
Leddy Anna M. Neilands Torsten B. Twine Rhian Kahn Kathleen Ahern Jennifer Pettifor Audrey Lippman Sheri A. 《AIDS and behavior》2022,26(5):1347-1354
AIDS and Behavior - We previously demonstrated that village community mobilization (CM) was associated with reduced HIV incidence among adolescent girls and young women (AGYW) in South Africa.... 相似文献
144.
A Gaudreau B Amor M F Kahn A Ryckewaert J Sany A P Peltier 《Annals of the rheumatic diseases》1978,37(4):321-327
Clinical and biological manifestations have been studied in 134 patients whose serum had antibodies to soluble extractable nuclear antigens (ENA). 85 of the patients had anti-RNP antibodies, 18 had anti-Sm antibodies, and 31 had antibodies to one or more soluble nuclear antigen. In all groups, the predominant clinical manifestations were polyarthritis, Raynaud's phenomenon, fever, and skin involvement. Renal disease was less common in those patients with anti-RNP antibodies than in the other patients. Most patients with definite renal disease (13 out of 15) also had circulating anti-DNA antibodies. The final diagnoses in these 134 patients were well defined connective tissue disease in 59; overlap syndromes in 34; a limited clinical syndrome made up of polyarthritis Raynaud's phenomenon--often with swollen fingers--and/or hypergammaglobulin-aemia in 31, and various other clinical conditions in 10. 相似文献
145.
Binding of tumor necrosis factor alpha (TNF-alpha) to high-affinity receptors on polymorphonuclear cells 总被引:1,自引:0,他引:1
S Pichyangkul D Schick F L Jia S Berent A Bollon A Kahn 《Experimental hematology》1987,15(10):1055-1059
The effects of tumor necrosis factor alpha (TNF-alpha) on human polymorphonuclear (PMN) cells were investigated. We found that 125I-TNF-alpha bound specifically to high-affinity receptors on PMN cells. At 4 degrees C, the binding occurred rapidly and reached steady state after 20 min. The Scatchard plot showed a single class of high-affinity receptors with approximately 2200 receptors/cell and a dissociation constant of 2 x 10(-10) M. There was a linear relationship between TNF-alpha binding and TNF-alpha-induced PMN cell adherence. The concentration of TNF-alpha required to achieve approximately 50% of maximum binding was also approximately the concentration required to reach 50% cell adherence. Auranofin was shown to inhibit TNF-alpha-induced PMN cell adherence at a dose of 5-10 micrograms/ml. This inhibitory effect was not due to the inhibition of TNF-alpha binding to PMN cells by the drug. These observations may have clinical implications. 相似文献
146.
J K Kahn 《Catheterization and cardiovascular diagnosis》1992,27(3):179-182
In order to examine the outcome of utilizing multiple balloon catheters during the percutaneous transluminal coronary angioplasty (PTCA), 300 consecutive PTCAs were analyzed. PTCA was performed in a single lesion in 163 patients (54%), in multiple lesions in 52 patients (18%), and in multiple vessels in 85 patients (28%). A total of 488 balloon catheters were used (1.6/case, range 1-9) and in 112 cases (37%) > or = 2 catheters were used. Multiple balloon catheters were needed in 27 single lesion (17%), 24 multilesion (48%), and 61 multivessel (72%) cases (p < .05). There was no difference in the angiographic success rate in cases completed with 1 balloon catheter (238/251, 95%) compared to those requiring > or = 2 catheters (260/274, 95%). Emergency bypass was required in 5 patients (1.7%) and there were 2 deaths (0.6%). Thus, although contemporary PTCA frequently requires multiple balloon catheters for completion, success rates remain high and appear to offset the increased procedural expenses. 相似文献
147.
To test the sensitivity and specificity of 99m-Technetium-Diphosphat myocardial scintigraphy in the diagnosis of acute myocardial infarction we examined the scintigrams of 53 patients admitted to our CCU. In all 38 patients with transmural myocardial infarction positive scintigrams with localized uptake of the tracer found. Myocardial imaging was performed 70--90 minutes after the intravenous injection of 15 mCi 99m-Technetium-Diphosphat in anterior and LAO position. The clinical value of the method for proving the presence or absence of a myocardial infarction is demonstrated on infarctions combined with bundle-branch block, pacemaker Ecg and on reinfarction. All normal cases in this group showed no tracer activity outside the bones. In unstable angina pectoris a faint but not localized tracer activity was found. 相似文献
148.
W H Frishman J Nadelmann W L Ooi S Greenberg M Heiman S Kahn H Guzik E J Lazar M Aronson 《American heart journal》1992,124(4):1026-1030
This report is from a 10-year cohort study of community-dwelling elderly men and women. Mean age at the time of entry into the study was 79 years. Annual chest x-ray studies were performed, and data are presented regarding prevalence, incidence, and prognosis of cardiomegaly. Cardiomegaly was defined as a transverse diameter of the cardiac silhouette greater than or equal to 50% of the transverse diameter of the chest (increased cardiothoracic ratio). At the time of entry into the study 110 subjects (23%) had cardiomegaly. After 10 years, 51% of the subjects with cardiomegaly at baseline died compared with 33% of the subjects without cardiomegaly (mortality rate = 9.1 vs 4.8/100 person-years respectively; p = 0.014). Cardiovascular disease incidence was also higher for those with preexisting cardiomegaly at baseline (rate 9.1 vs 6.1/100 person-years; p = 0.0001). According to the Cox proportional hazards regression analysis, age, cardiomegaly, diabetes, and prior evidence of myocardial infarction were independent predictors for death in this cohort. Similarly, the best predictive variables for cardiovascular disease were age, diabetes, prior evidence of myocardial infarction, and cigarette smoking. Of the 359 subjects without cardiomegaly at baseline, 108 (30%) showed evidence of new cardiomegaly, and their risk of cardiovascular disease was 1.8 times that of subjects whose test results were negative for cardiomegaly throughout the study (p = 0.003). Thus cardiomegaly, as defined by an increased cardiothoracic ratio on x-ray films, irrespective of cause, is associated with a poor prognosis in very elderly men and women. 相似文献
149.
Diagnosis,management, and clinical outcome of cardiac tamponade complicating percutaneous coronary intervention 总被引:23,自引:0,他引:23
Fejka M Dixon SR Safian RD O'Neill WW Grines CL Finta B Marcovitz PA Kahn JK 《The American journal of cardiology》2002,90(11):1183-1186
Cardiac tamponade is an uncommon but life-threatening complication of percutaneous coronary intervention (PCI). The purpose of the present study was to characterize the incidence, management, and clinical outcome associated with this complication. We analyzed a prospective database of 25,697 PCIs performed at William Beaumont Hospital (Royal Oak, Michigan) between October 1993 and December 2000. Cardiac tamponade was observed in 31 of 25,697 PCI procedures (0.12%). Cardiac tamponade was diagnosed in the catheterization laboratory in 17 of 31 patients (55%), and 14 patients (45%) had a delayed presentation (mean time from PCI 4.4 hours). Cardiac tamponade was twice as frequent after use of atheroablative devices compared with percutaneous transluminal coronary angioplasty and stenting (0.26% vs 0.11%, p <0.05). All patients with immediate cardiac tamponade had coronary artery perforation. In 11 of 14 patients with delayed tamponade (79%), no actual site of perforation could be identified. A moderate or large pericardial effusion was observed in 20 patients, and 9 had small effusions without typical echocardiographic features of tamponade. Pericardiocentesis was performed in 30 patients; 19 patients (61%) were treated successfully with aspiration alone, but 12 patients (39%) required further emergency surgical intervention. In-hospital complications included death (42%), emergency surgery (39%), myocardial infarction (29%), and transfusion (65%). Cardiac tamponade is an uncommon but important complication of PCI and is associated with high mortality and morbidity. Most cases are recognized in the catheterization laboratory, but delayed cardiac tamponade may occur and must be considered as a cause of late hypotension after PCI. 相似文献
150.
Sodium-lithium exchange in sarcolemmal vesicles from canine superior mesenteric artery 总被引:1,自引:0,他引:1
Exchange of intracellular sodium for extracellular lithium readily occurs in vascular smooth muscle, but the mechanism of this exchange is not known. These studies examined whether a sodium-lithium countertransport system was present in the cell membrane of vascular smooth muscle. A sarcolemmal-enriched vesicle preparation was obtained from canine superior mesenteric artery via a magnesium aggregation and differential centrifugation technique. An outwardly directed gradient for lithium stimulated 22Na uptake by the vesicles, and an inwardly directed gradient for lithium stimulated 22Na efflux. These effects were not due to an alteration in membrane potential, and sodium uptake was not stimulated by lithium in the absence of a gradient for lithium. The lithium gradient-stimulated component of sodium uptake was not affected by a change in membrane potential and was insensitive to ouabain. Both sodium-lithium exchange and sodium-proton exchange in sarcolemmal-enriched vesicles were inhibited by two compounds that inhibit the sodium-lithium countertransport system in red cells, phloretin and quinidine. Ethylisopropylamiloride also inhibited both sodium-lithium exchange and sodium-proton exchange in the vesicles. In support of the possibility that sarcolemmal sodium-lithium exchange and sodium-proton exchange are mediated by a single cation exchange mechanism with affinity for sodium, lithium, and protons, we found that an inwardly directed sodium or lithium gradient stimulated proton efflux, and that the stimulation of sodium efflux by external lithium or protons was not additive. It is concluded from these studies that sarcolemmal vesicles from canine superior mesenteric artery contain an electroneutral, phloretin, quinidine, and ethylisopropylamiloride inhibitable sodium-lithium exchange transport system.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献