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21.
Alexander Egbe Sorin V. Pislaru Mahmoud A. Ali Arooj R. Khan Amber N. Boler Hartzell V. Schaff Emmanuel Akintoye Heidi M. Connolly Vuyisile T. Nkomo Patricia A. Pellikka 《JACC: Cardiovascular Imaging》2018,11(7):951-958
Objectives
The purpose of this study was to review the institutional practice of surveillance transthoracic echocardiography (TTE) for diagnosing early prosthetic valve dysfunction (PVD).Background
Bioprosthetic valve thrombosis (BPVT) is an important cause of PVD, and guidelines do not recommend routine TTE during the first 5 years after valve implantation.Methods
The authors performed a retrospective case-control study of all suspected (imaging diagnosis) or confirmed (histopathological diagnosis) cases of BPVT from January 1997 through December 2016. Patients were matched 1:2 (age, sex, prosthesis position) to patients whose prostheses were explanted because of structural failure (SF). PVD was defined as a 50% increase above baseline gradient at valve implantation and classified as early (≤5 years) or late (>5 years) after implantation.Results
There were 94 BPVT (51 suspected, 43 confirmed) and 188 SF cases; patient age 61 ± 9 years; men 61 (65%). The prosthesis positions were aortic 56%; mitral 26%; tricuspid 15%; and pulmonary 3%. Early PVD was more common in the BPVT versus SF group: 83 of 94 (88%) versus 20 of 188 (11%) (p < 0.001). Time from implantation to PVD was shorter for BPVT than SF: 26 months (interquartile range [IQR]: 12 to 43 months) versus 74 months (IQR: 48 to 102 months) (p < 0.001). At the initial PVD diagnosis, 81% of BPVT and 90% of SF patients were asymptomatic. However, BPVT patients had rapid symptomatic deterioration, requiring intervention sooner after PVD diagnosis: 6 months (IQR: 4 to 7 months) versus 51 months (IQR: 22 to 55 months) (p < 0.001).Conclusions
Most patients with PVD due to BPVT were asymptomatic at initial diagnosis, which was made based on routine surveillance TTE, often performed before 5 years. BPVT, an acute disease process, requires timely diagnosis because patient conditions rapidly deteriorate. Further studies are needed to determine whether routine surveillance TTE should be considered for patients with bioprosthetic valves to identify pre-symptomatic features of BPVT in order to provide effective, appropriate therapy. 相似文献22.
Talreja DR Nishimura RA Edwards WD Valeti US Ommen SR Tajik AJ Dearani JA Schaff HV Holmes DR 《Journal of the American College of Cardiology》2004,44(12):2329-2332
OBJECTIVES: This study was designed to evaluate the effect of septal reduction therapies on the conduction system for patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Heart block is a potential complication of both catheter-based and surgical procedures to relieve left ventricular outflow tract obstruction in HCM, but it is important to understand the different effects of these treatments on the conduction system. METHODS: The electrocardiograms and postoperative course of patients who underwent percutaneous alcohol septal ablation or surgical myectomy at Mayo Clinic between 1999 and 2003 were reviewed. RESULTS: For the 58 patients who underwent alcohol septal ablation, 21 (36%) developed right bundle branch block. Six patients (12%) developed complete heart block requiring permanent pacing, three of whom had left bundle branch block before the procedure. Among the 117 patients who underwent surgical septal myectomy, 47 (40%) developed left bundle branch block. Four patients (3%) developed heart block requiring permanent pacing after the procedure, three of whom had right bundle branch block preoperatively. CONCLUSIONS: Percutaneous septal ablation selectively produces transmural infarction of the basal mid-septum and adjacent right bundle tissue, whereas surgical myectomy affects the endocardial portion of the basal anterior septum and adjacent left bundle tissue. These observations may help identify patients at risk for complete heart block after septal reduction procedures for HCM. 相似文献
23.
Johannes Wolf Jonathan I. Sperl Florian Schaff Markus Schüttler Andre Yaroshenko Irene Zanette Julia Herzen Franz Pfeiffer 《Biomedical optics express》2015,6(12):4812-4824
X-ray grating interferometry requires gratings with periods in the micrometer range and allows the acquisition of the dark-field contrast. The analyzer grating is designed to match the period of the interference pattern in order to translate it into a measurable intensity modulation. In this study, we explore the influence of a sample-induced mismatch between the interference pattern and the analyzer grating on the dark-field contrast. We propose a formula for the calculation of the signal due to a period mismatch and present estimations varying periods and detector pixel size. Furthermore, numerical simulations of the X-ray wave-front demonstrate that the wave-front curvature, described by the lens-term, e.g. behind a parabolic lens or edges of a sample can change the period of the interference pattern. Our results give a concrete explanation for the formation of a dark-field contrast from object edges and thus allow a better understanding of the dark-field signal obtained with a grating interferometer.OCIS codes: (110.7440) X-ray imaging, (340.7450) X-ray interferometry 相似文献
24.
BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8) 相似文献
25.
26.
Employing the arts for knowledge production and translation: Visualizing new possibilities for women speaking up about safety concerns in maternity 下载免费PDF全文
27.
Brown ML Holmes DR Tajik AJ Sarano ME Schaff HV 《Mayo Clinic proceedings. Mayo Clinic》2007,82(5):572-574
OBJECTIVE: To maximize patient convenience, we developed a protocol for coronary angiography the same day as elective valvular surgery. PATIENTS AND METHODS: We analyzed the medical records from a single surgical service of 226 consecutive patients who had undergone cardiac catheterization on the day of elective valvular repair or replacement between August 1, 2000, and August 30, 2004. The rates of renal failure (creatinine >2.0 mg/dL and 2 times the preoperative level), hemodialysis, continuous renal replacement therapy, and mortality were evaluated. RESULTS: Patients undergoing same-day angiography had a mean age of 65.6 plus-or-minus 12.1 years, and 33% were female. Of the study patients, 11.1% were diabetic, with a mean ejection fraction of 61% plus-or-minus 10%, and 28.3% had coronary artery disease severe enough to require bypass grafting. One patient died within 30 days of surgery; the overall mortality was 0.4%. Postoperatively, serum creatinine levels increased an average of 0.1 mg/dL (P<.001) in patients undergoing same-day coronary angiography. Four patients had transient renal failure (1.8%), 2 of whom required temporary hemodialysis. CONCLUSION: In properly selected patients, same-day coronary angiography is safe and has little impact on renal function. This protocol offers a simple way to reduce the number of hospital visits required by patients undergoing elective valvular surgery. 相似文献
28.
ElBardissi AW Dearani JA Nishimura RA Ommen SR Stulak JM Schaff HV 《Mayo Clinic proceedings. Mayo Clinic》2007,82(12):1516-1522
OBJECTIVE: To review our institution's experience with patients who failed to benefit from septal artery ablation, which necessitated subsequent septal myectomy, and to examine reasons for ablation failure and outcome of myectomy after ablation. PARTICIPANTS AND METHODS: Of 550 patients who underwent septal myectomy at Mayo Clinic Rochester between January 1, 1999, and December 31, 2006, 16 (3%) had had a total of 22 previous septal artery ablations. This subset of 16 patients was analyzed and compared with a reference group of 120 patients whose septal artery ablations were performed at our institution during this period. Angiograms obtained during septal ablation were available for 13 (81%) of 16 patients in this series and were reviewed by 2 interventional cardiologists (R.A.N. and S.R.O.). These cardiologists also reviewed preoperative and postoperative echocardiography data, hospital course, and follow-up data to compile a list of characteristics that could have contributed to failed ablation. RESULTS: The median age of the patients at operation was 65 years (interquartile range [IQR], 52-72 years), and interval between ablation and myectomy was 409 days (IQR, 162-568 days). Angiograms revealed 2 failed procedures secondary to technical error. One patient had a relatively large first septal perforator with a large resting gradient. In 10 patients no septal perforators supplying the proximal septum were identified. Postoperatively, mitral regurgitation decreased from 3.00 to 1.00 (P less than .001), and left ventricular outflow tract gradient decreased from 75 mm Hg to 0 mm Hg (IQR, 0-29 mm Hg; P less than .001). Two patients died after surgery: 1 patient developed multiple-organ system failure on postoperative day 7, and 1 patient developed arrhythmia on postoperative day 21. Patients with previous septal artery ablation were older (P=.04), were more likely to have preoperative permanent pacemakers or implantable cardioverter-defibrillators (P=.05), were more likely to require postoperative pacemaker placement (P less than .001), and had higher operative mortality (P less than .001) than control patients. Fourteen patients survived the early recovery phase; 9 were followed up at a median of 1.88 years (IQR, 306 days to 3.3 years). All patients' symptoms improved. Median gradient of the left ventricular outflow tract was 13 mm Hg (IQR, 0-15 mm Hg) at follow-up with mild to moderate (1.6) mitral regurgitation. CONCLUSION: Septal myectomy performed after failed ablation improves gradient and provides excellent relief of symptoms but is associated with a higher incidence of morbidity and mortality. 相似文献
29.
Hogan WJ McBane RD Santrach PJ Plumhoff EA Oliver WC Schaff HV Rodeheffer RJ Edwards WD Duffy J Nichols WL 《Mayo Clinic proceedings. Mayo Clinic》2000,75(9):971-976
Hemostatic aspects of antiphospholipid syndrome (APS) present unique challenges to clinicians and laboratory personnel alike, particularly in the perioperative period. These challenges are especially evident in patients requiring cardiac valve replacement surgery. However, the literature outlining the optimal approach in such patients is limited. We present the case of a 25-year-old woman with severe aortic regurgitation as a result of APS with particular reference to the precautions necessary during perioperative care. Particularly important are the prevention of thrombotic or hemorrhagic complications, management of associated thrombocytopenia, and laboratory methods of perioperative anticoagulation monitoring in the setting of prolonged clotting times. 相似文献
30.
Susan Jenkins-Clarke BSc RGN HV Cert & Roy Carr-Hill MA DPhil 《Journal of advanced nursing》2001,34(6):842-849
AIMS: The main aim of this paper is to draw attention to problems facing the primary health care workforce in terms of demand for treatment of minor illness over the next two decades. These predictions have implications for the community nursing workforce in particular and the flexibility of primary health care teams in general. BACKGROUND: Care delivered in the primary care sector influences, and is influenced by, the characteristics of the health care workforce. These characteristics fall into two main groups: firstly, the shape of the present medical and nursing workforce and manpower trends; and secondly, the changes in doctors' and nurses' workloads. DESIGN: This paper draws on two studies, both commissioned by the Department of Health; the first study focusing on skill mix and delegation in primary health care teams and the second addressing the implications of skill mix for medical workforce scenarios in the changing policy environment. FINDINGS: From the first study, general practitioners across ten general practices were prepared to delegate at least one topic from over a third of 836 consultations and a further 17% of entire consultations. This potential delegation fell mainly to practice nurses and nurse practitioners. The second study used data extracted from the National Morbidity Surveys of 1981 and 1991 predicting that minor consultations are set to increase by 11 million from the 1990s to 2020--a minimal estimate. The authors argue that many of these extra predicted consultations will find their way onto practice nurses' and nurse practitioners' caseloads. CONCLUSIONS: Workforce issues and questions of professional roles and boundaries, in the context of the "greying" community nursing workforce, demand solutions if patient/client demand is to be met over the next two decades. 相似文献