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951.
952.
Maria Odqvist Per-Ola Andersson Hans Tygesen Kai M. Eggers Martin J. Holzmann 《Journal of the American College of Cardiology》2018,71(23):2616-2624
Background
It remains unknown how the introduction of high-sensitivity cardiac troponin T (hs-cTnT) has affected the incidence, prognosis, and use of coronary angiographies and revascularizations in patients with myocardial infarction (MI).Objectives
The aim of this study was to investigate how the incidence of MI and prognosis after a first MI was affected by the introduction of hs-cTnT.Methods
In a cohort study, the authors included all patients with a first MI from the Swedish National Patient Registry from 2009 to 2013. Cox regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for risk of all-cause mortality, reinfarction, coronary angiographies, and revascularizations in patients with MI diagnosed using hs-cTnT compared with those diagnosed using conventional troponins (cTn).Results
During the study period, 47,133 MIs were diagnosed using cTn and 40,746 using hs-cTnT. The rate of MI increased by 5% (95% CI: 0% to 10%) after the introduction of hs-cTnT. During 3.9 ± 2.8 years of follow-up, there were 33,492 deaths, with no difference in the risk of all-cause mortality (adjusted HR: 1.00; 95% CI: 0.97 to 1.02). There were, in total, 15,766 reinfarctions during 3.1 ± 2.3 years of follow-up, with the risk of reinfarction reduced by 11% in patients diagnosed using hs-cTnT (adjusted HR: 0.89; 95% CI: 0.86 to 0.91). The use of coronary angiographies (adjusted HR: 1.16; 95% CI: 1.14 to 1.18) and revascularizations (adjusted HR: 1.13; 95% CI: 1.11 to 1.15) increased in the hs-cTnT group.Conclusions
In a nationwide cohort study including 87,879 patients with a first MI, the introduction of hs-cTnT was associated with an increased incidence of MI, although with no impact on survival. We also found a reduced risk of reinfarction alongside increased use of coronary angiographies and revascularizations. 相似文献953.
954.
AIMS: To establish the normal range of diastolic and systolic left ventricular wall-to-cavity ratios. METHODS AND RESULTS: Two hundred and sixty-two normal subjects (age 0-40 years), 15 children with valvar aortic stenosis and 11 childhood athletes were studied with M-mode echocardiography. Values of diastolic septum-to-cavity ratio and diastolic left ventricular wall-to-cavity ratio were not influenced by sex nor, in adults, by height, weight or body surface area. There were slight age variations from 0-15 years of age, but not in adults from 15-40 years of age. Values of diastolic left ventricular wall-to-cavity ratio in neonates were 0.18 (95% confidence limits 0.17-0.19); in 3-5 year olds 0.16 (0.15-0.16); and in adults 0.18 (0.17-0.19). In valvar aortic stenosis there is a positive correlation between the Doppler-estimated pressure gradient and the degree of left ventricular hypertrophy, as expressed by both diastolic and systolic left ventricular wall-to-cavity ratio (r = 0.90;P < 0.00001 and r = 0.85;P = 0.00006 respectively). CONCLUSIONS: Diastolic septum and left ventricular wall-to-cavity ratios accurately differentiate physiological from pathological left ventricular hypertrophy in the growing child. Because these ratios are independent of sex and body size, they may also be more sensitive than absolute wall thickness in the detection of abnormal left ventricular hypertrophy in adults. 相似文献
955.
Cardiac resynchronization therapy (CRT) devices have been studied clinically since 1998, and have been on the U.S. market since the Food and Drug Administration (FDA) approval of the first product in 2001. Since that time, the FDA has approved many different models from three different manufacturers, representing the first and second generations of these products. All of these products have undergone the FDA pre-market approval process, which examines the safety and effectiveness of the devices for their intended use. Over the last several years, the FDA has adapted recommendations for CRT clinical trials based on an evolving understanding of what these devices can achieve. This paper will outline the dynamic nature of the FDA's approval process for CRT devices and briefly review the clinical trial designs for the first generation devices. 相似文献
956.
J. D. Waldman J. S. Pappelbaum S. W. Turner 《Catheterization and cardiovascular interventions》1977,3(3):321-326
Retrograde arterial catheterization has been the standard approach to hemodynamic and angiographic evaluation of the left ventricle and systemic arterial system. An alternative approach—antegrade left heart catheterization—is reported that circumvents arterial puncture. During cardiac catheterization from the femoral vein in 18 children with normally related great arteries who had interatrial communications, a balloon-tipped catheter was looped in a ?clockwise”? fashion through the left atrium and left ventricle and into the ascending aorta. In 17 children the maneuver was rapidly accomplished without complications; it proved possible to perform in an infant with a hypoplastic left ventricular cavity, and was employed to perform a renal arteriogram. The major advantage of antegrade left heart catheterization is avoidance of complications related to arterial puncture. The antegrade approach also avoids right arm cut-down in children with coarctation of the aorta. 相似文献
957.
《JACC: Cardiovascular Interventions》2020,13(11):1357-1368
ObjectivesThe aim of this study was to describe the performance and outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in Michigan.BackgroundCTO PCI has been associated with reduction in angina, but previous registry analyses showed a higher rate of major adverse cardiac events with this procedure.MethodsTo study uptake and outcomes of CTO PCI in Michigan, patients enrolled in the BMC2 (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) registry (2010 to 2017) were evaluated. CTO PCI was defined as intervention in a 100% occluded coronary artery ≥3 months old.ResultsAmong 210,172 patients enrolled in the registry, 7,389 CTO PCIs (3.5%) were attempted, with 4,614 (58.3%) achieving post-procedural TIMI (Thrombolysis In Myocardial Infarction) flow grade 3. The proportion of PCIs performed on CTOs increased over the study period (from 2.67% in 2010 to 4.48% in 2017). Thirty of 47 hospitals performed >50 CTO interventions in 2017. Pre-procedural angina class ≤2 was present in one-quarter, and functional assessment for ischemia was performed in 46.6% of patients. Major complications occurred in 245 patients (3.3%) and included death (1.4%), post-procedural stroke (0.4%), cardiac tamponade (0.5%), and urgent coronary artery bypass graft surgery (1.3%). Procedural success improved modestly from 44.5% in 2010 to 54.9% in 2017 (p for trend < 0.001). Rates of in-hospital mortality (p for trend = 0.247) and major adverse cardiac event (p for trend = 0.859) for CTO PCI remained unchanged over the study period.ConclusionsThe rate of CTO PCI in Michigan increased over the study period. Although the success rate of CTO PCI has increased modestly in contemporary practice, it remained far below the >80% reported by select high-volume CTO operators. The rate of periprocedural major adverse cardiac events or death remained unchanged over time. These data suggest room for improvement in the selection and functional assessment of CTO lesions before subjecting patients to the increased procedural risk associated with CTO PCI. 相似文献
958.
近年来,随着对心房颤动(房颤)临床观察研究的不断深入,发现一种较为普通存在的现象,即房颤患者其动态心电监护多见有明显R-R间期延长,同时有研究表明房颤伴长R-R间期与心脏性猝死有一定的相关性,并且临床医生为避免这一猝死现象往往选择了心脏起搏治疗来预防猝死,现将房颤伴长R-R间期与心脏性猝死的关系做一综述. 相似文献
959.
960.
Charles Katzenberg Edna Silva M. Jean Young Greg Gilles 《The American journal of medicine》2018,131(8):967-971