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排序方式: 共有1439条查询结果,搜索用时 31 毫秒
31.
Thiele H Hambrecht R Lauer B Weinert M Mohr FW Schuler G 《The Journal of heart valve disease》2001,10(1):129-135
BACKGROUND AND AIM OF THE STUDY: Intraoperative swabs of heart valves are obtained regularly from patients undergoing heart valve surgery for infective endocarditis (IE) in order to confirm the preoperative diagnosis and to adjust the antibiotic regimen. The study aim was to assess the diagnostic value of intraoperative swabs of heart valves in IE. METHODS: A total of 83 patients was referred for surgical treatment of active IE between October 1994 and May 1999. Preoperatively, microorganisms were isolated using a minimum of two positive blood cultures; results were compared with those obtained from intraoperative heart valve swab cultures. RESULTS: Preoperatively, 73 patients (88%) had a positive blood culture, and 10 (12%) had culture-negative endocarditis. The intraoperative swab confirmed the preoperative diagnosis in 31 cases (37%). Bacteria were isolated in three of the ten patients with preoperative culture-negative IE. Despite positive histopathological findings in seven patients, no microorganisms were cultured either pre- or intraoperatively. Among the remaining 42 patients (51%) with active IE, 25 valve cultures were sterile and 17 valve swabs were presumed to be contaminated. CONCLUSION: In patients with active IE in whom the causative agent could be isolated and identified before surgery, intraoperative valve swabs did not contribute further to patient management. In isolating contaminants, the risk of inappropriate modification of the antibiotic regimen is imminent. The diagnostic validity in culture-negative IE appears negligible. 相似文献
32.
33.
Chronotropic response to exercise predicts angiographic severity in patients with suspected or stable coronary artery disease 总被引:9,自引:0,他引:9
Sorin J. Brener MD Fredric J. Pashkow MD Sharon A. Harvey MS Thomas H. Marwick MD James D. Thomas MD Michael S. Lauer MD 《The American journal of cardiology》1995,76(17):1228-1232
Inappropriate chronotropic response to exercise has been observed to correlate with poor prognosis in patients with coronary disease, but the mechanism for this association is not well defined. We attempted to examine the association between chronotropic response to exercise and angiographic severity of coronary disease in patients with suspected or stable coronary artery disease. The chronotropic response, expressed as peak heart rate, chronotropic index (ratio of heart rate reserve and metabolic reserve utilized), or percent maximal heart rate achieved, was correlated with angiographic findings obtained within 180 days of the test. Significant coronary disease was defined as ≥1 stenosis of ≥50% in a major epicardial artery or its main branches; severe coronary disease was defined as ≥50% stenosis in all 3 epicardial arteries, or in the left main coronary trunk, or 2-vessel disease with ≥70% proximal left anterior descending artery stenosis. We observed that peak heart rate and percent maximal heart rate achieved were independent negative predictors of both significant and severe coronary disease by logistic regression. The chronotropic index predicted severe coronary disease only. All 3 parameters of chronotropic response exhibited a significant gradient of abnormality across the spectrum of coronary disease (p < 0.01 for all), expressed by the number of vessels involved and correlated with left anterior descending artery involvement (p < 0.05 for all). We conclude that chronotropic response to exercise predicts the presence and angiographic severity of coronary disease. This association is likely related to the proportion of left ventricular myocardium rendered ischemic during stress. 相似文献
34.
BACKGROUND: Heart rate recovery (HRR) after exercise correlates with decreased vagal tone and mortality. Patients with COPD may have altered autonomic tone. We sought to determine the association of HRR with spirometry measures of pulmonary function. METHODS: We analyzed 627 patients (mean [+/- SD] age, 58 +/- 12 years; 65% men; mean FEV(1), 2.6 +/- 0.9 L, 80 +/- 20% predicted; patients receiving inhaled beta(2) agonist therapy, 10%; patients receiving inhaled anticholinergic therapy, 3%; patients receiving inhaled steroids, 5%; patients receiving oral prednisone, 4%) who had undergone maximal exercise testing and had undergone pulmonary function tests < 1 year apart. Patients with heart failure, pacemakers, and atrial fibrillation were excluded. Abnormal HRR was defined as a fall in heart rate during the first minute after exercise of 相似文献
35.
Mahon NG Blackstone EH Francis GS Starling RC Young JB Lauer MS 《Journal of the American College of Cardiology》2002,40(6):1106-1113
OBJECTIVES: The goal of this study was to determine the prognostic significance of estimated creatinine clearance (CrCl) in relation to 6-min walk distance in ambulatory patients with congestive heart failure (HF). BACKGROUND: Although measurement of renal function is integral to the management of chronic congestive HF, its prognostic implications are not well described and have not been formally evaluated relative to measures of functional capacity. METHODS: We analyzed outcomes of the 585 participants of the 6-min walk substudy of the Digitalis Investigation Group (DIG) trial. The CrCl was estimated using the Cockcroft-Gault equation. Predictors of all-cause mortality were identified using semiparametric Cox proportional hazards regression and completely parametric hazard analyses. RESULTS: Most subjects (85%) were New York Heart Association functional class II and III. Mean age was 65 (+/-12) years and mean ejection fraction (EF) 35% (+/-13%). There were 153 (26%) deaths during a median of 2.6 years of follow-up. Mortality by increasing quartiles of estimated CrCl was 37% (18 to 48 ml/min), 29% (47 to 64 ml/min), 18% (64 to 86 ml/min), and 21% (86 to 194 ml/min) with corresponding hazard ratios (HRs) relative to the top quartile of 2.1 (95% confidence interval [CI], 1.4 to 3.3), 1.6 (95% CI, 1.0 to 2.5), and 0.9 (95% CI, 0.5 to 1.5), respectively. In Cox regression analyses, independent predictors of mortality were estimated CrCl (adjusted HR [quartile 1:quartile 4] 1.5; 95% CI, 1.1 to 2.1), 6-min walk distance < or =262 m [adjusted HR, 1.63; 95% CI, 1.12 to 2.27]), EF, recent hospitalization for worsening HF, and need for diuretic treatment. Parametric (hazard) analysis confirmed consistent effects of estimated CrCl on mortality in several subgroups including that of patients with EF >45%. CONCLUSION: In ambulatory patients with congestive HF, estimated CrCl predicts all-cause mortality independently of established prognostic variables. 相似文献
36.
Tomislav Mihaljevic Buu-Khanh Lam Jeevanantham Rajeswaran Masami Takagaki Michael S Lauer A Marc Gillinov Eugene H Blackstone Bruce W Lytle 《Journal of the American College of Cardiology》2007,49(22):2191-2201
OBJECTIVES: The aim of this work was to determine whether mitral valve (MV) annuloplasty benefits patients with moderate/severe (3+/4+) functional ischemic mitral regurgitation (MR) who undergo coronary artery bypass grafting (CABG). BACKGROUND: Mitral regurgitation is a strong predictor of poor outcomes in patients with ischemic cardiomyopathy; whether correcting it at the time of CABG improves outcomes is less certain. METHODS: From 1991 to 2003, 390 patients with 3+/4+ ischemic MR had CABG with (n = 290) or without (n = 100) MV annuloplasty. Groups were propensity-matched using demographics, extent of coronary disease, regional wall motion, and quantitative electrocardiography. Survival, echocardiographic severity of MR, and New York Heart Association (NYHA) functional class were compared. RESULTS: One-, 5-, and 10-year survival was 88%, 75%, and 47% after CABG alone and 92%, 74%, and 39% after CABG + MV annuloplasty (p = 0.6). Mortality was increased in patients with severe lateral wall motion abnormalities (p = 0.05), ST-segment elevation in lateral leads (p < 0.004), and higher QRS voltage sum (p < 0.0001). Patients undergoing CABG alone were more likely to have 3+/4+ postoperative MR than those undergoing CABG + MV annuloplasty (48% vs. 12% at 1 year, p < 0.0001). The NYHA functional class substantially improved in both groups (p < 0.001) and remained improved; at 5 years, 23% of patients having CABG + mitral annuloplasty and 25% having CABG alone were in NYHA functional class III/IV. CONCLUSIONS: Although CABG + MV annuloplasty reduces postoperative MR and improves early symptoms compared with CABG alone, it does not improve long-term functional status or survival in patients with severe functional ischemic MR. The MV annuloplasty in this setting, without addressing fundamental ventricular pathology, is insufficient to improve long-term clinical outcomes. 相似文献
37.
C. R. Werner C. Franz D. P. Egetemeyr P. Janke‐Maier N. P. Malek U. M. Lauer C. P. Berg 《Journal of viral hepatitis》2014,21(5):333-340
Since 2011, telaprevir (TVR)‐based triple therapy is the new treatment standard for hepatitis C genotype 1 virus infection. The aim of our retrospective interim analysis encompassing the first 24 weeks on TVR‐based triple therapy was to assess ‘real‐life’ antiviral efficacy and side effects in a large single‐centre cohort, both in comparison with the data obtained in large prospective clinical trials. In total, we treated 102 patients: 24 treatment‐naïve patients, 58 patients pretreated with PEG‐IFN/RBV (thereof: 28 with nonresponse, 25 with relapse, five unknown) and 20 patients who previously had received nonpegylated interferon. 74 of 102 patients were assigned with HCV genotype 1b; 34 of 102 patients were treated in the context of liver cirrhosis. 72 of 102 patients have reached treatment week 24 (mean treatment duration 31 weeks). In the ITT analysis, overall response rates were at: week 4: 66%; week 12: 85%; and week 24: 78%. So far, 24 patients discontinued treatment prematurely, of those, 10 patients were due to virological failure. Haematological side effects were frequent (40% anaemia), as were ‘flu‐like’ symptoms (94%), rash (65%) and pruritus (79%). According to our interim ITT analysis encompassing up to 24 weeks of TVR‐based triple therapy, our ‘real‐life’ antiviral effects are comparable to the results of large multicentric clinical trials. However, TVR‐based triple therapy exhibited a high frequency of side effects requiring multiple therapeutic interventions. Notably, in our ‘real‐life’ cohort, no lethal case was observed so far. 相似文献
38.
Brandt Silvia Brandt Jan Ketabi Ali-Reza Lauer Hans-Christoph Kunzmann Anna 《Clinical oral investigations》2019,23(2):763-770
Clinical Oral Investigations - Implant-supported overdentures are an established dental treatment mode. The aim of this prospective study was and interindividual comparison of patient satisfaction... 相似文献
39.
Over the past 50 years, we have seen dramatic changes in cardiovascular science and clinical care, accompanied by marked declines in the morbidity and mortality. Nonetheless, cardiovascular disease remains the leading cause of death and disability in the world, and its nature is changing as Americans become older, fatter, and ethnically more diverse. Instead of young or middle-aged men with ST-segment elevation myocardial infarction, the "typical" cardiac patient now presents with acute coronary syndrome or with complications related to chronic hypertension or ischemic heart disease, including heart failure, sudden death, and atrial fibrillation. Analogously, structural heart disease is now dominated by degenerative valve or congenital disease, far more common than rheumatic disease. The changing clinical scene presents cardiovascular scientists with a number of opportunities and challenges, including taking advantage of high-throughput technologies to elucidate complex disease mechanisms, accelerating development and implementation of evidence-based strategies, assessing evolving technologies of unclear value, addressing a global epidemic of cardiovascular disease, and maintaining high levels of innovation in a time of budgetary constraint and economic turmoil. 相似文献
40.
Thiele H Schuler G Neumann FJ Hausleiter J Olbrich HG Schwarz B Hennersdorf M Empen K Fuernau G Desch S de Waha S Eitel I Hambrecht R Böhm M Kurowski V Lauer B Minden HH Figulla HR Braun-Dullaeus RC Strasser RH Rochor K Maier SK Möllmann H Schneider S Ebelt H Werdan K Zeymer U 《American heart journal》2012,163(6):938-945