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51.
The effect on left ventricular function of a gradual withdrawalof chronic metoprolol treatment in postinfarction patients wasstudied. All patients were in a randomized double-blind post-infarctionstudy with metoprolol (M 100–200 mg daily; N=14) or placebo(P; N =18). After three years treatment the study medicationwas gradually withdrawn during one week. M-mode echocardiography,guided by concomitant cross-sectional recordings, were performedbefore, one and 12 weeks after the withdrawal. Treatment (i.e.M or P) had to be reinstituted in eight patients (5 M; 3P) becauseof the development of disabling symptoms during the follow-up.Heart rate was lower in patients treated with M (57±4)than with P (69±10) (p<0.01). One week after withdrawalof M, heart rate had increased to 77± 13(p<0.001),while patients on P showed no significant change. In order tominimize the influence of heart rate on the evaluation of timeintervals in the cardiac cycle, heart rate dependent correctionfactors were used. One week after M withdrawal there was a prolongationof the pre-ejection period (PEP) from 120±15 ms to 133±16ms (p< 0.01), mainly due to a prolongation of the intervalfor early isovolumetric contraction (Q Mc) from 87±10ms to 101±11 ms (N=11; p0.001). Simultaneously, valuesfor isovolumetric relaxation increased from 228±28msto 286±39 MS (n = 11; p0.001), starting from a somewhatlower value than P before withdrawal, reaching an insignificantlyhigher level and returning to the levels of P. During withdrawalof P stable values were encountered. Twelve weeks after withdrawal,there were no longer significant differences between M and Pgroups. In conclusion, after a one week gradual withdrawal ofM in patients with ischaemic heart disease, a transient increaseof both isovolumetric contraction and relaxation phases occur,suggesting depressed myocardial function, despite a transientrebound increase in heart rate.  相似文献   
52.
Infection is a rare complication of cardiac mural thrombus andmay prove difficult to diagnose and treat. We describe a patientwith infected thrombus associated with a left ventricular aneurysm,involving Salmonella typhimurium. Cross-sectional echocardiographyproved helpful in establishing the diagnosis.  相似文献   
53.
The aim of the present investigation was to discover whetherdisturbed left ventricular (LV) function limits renal replacementtherapy in patients with juvenile onset diabetes mellitus. Seventeenpatients given functioning kidney grafts were studied non-invasively(M-mode echocardiography, apexcardiography, phonocardiography)before renal transplant and an average of six, 13 and 44 monthsafter transplant. The main pretransplant findings were pronouncedLV hypertrophy with impaired diastolic LV function (prolongedrelaxation time + signs of decreased LV distensibility) anda hyperdynamic circulation. Most of these abnormalities were significantly less severe aftersuccessful kidney transplantation. LV mass decreased by 37%44 months after transplant (p<0.01) and LV diastolic andsystolic volumes decreased with a subsequent increase in ejectionfraction from 0.65 to 0.78 (p<0.01). The LV distensibilityand filling pattern improved significantly while the prolongedrelaxation time was unchanged. These findings imply that pretransplant disturbances in LV functionare related more to factors such as hypertension, volume overloadand uraemia than to diabetes per se because no pronounced improvementin the metabolic disorder resulting from diabetes can be expected,even after the most successful transplant. Disturbed LV functionshould not, therefore, exclude uraemic diabetics from renalreplacement.  相似文献   
54.
Early in 1956, the first model of a biological artificial liver, using a live dog's liver incorporated in a cross-hemodialyzer, was placed in an experimental animal with portocaval encephalopathy. This "biological artificial liver," a hybrid artificial liver in the present terminology, was the first in the world. In October 1958, the first human patient, a young male patient in hepatic coma due to liver cirrhosis, was placed on the laboratory-made biological artificial liver composed of four parabiotic cross-hemodialyzers connected with four live dogs' livers to which the "hepatic reactors" for ammonium adsorption and acid-base balance were additionally equipped. This first case was very successful, resulting in the patient's recovery from coma. This article introduces the past history of the artificial liver, research of which has mainly been conducted in Japan since the early 1950s by the author, M. Mito, and Y. Nosé. Until recently, little progress has been made in this field through the application of blood purification principles such as hemoadsorption, plasmapheresis, and other modifications and combinations. Accumulation of clinical experiences with such conventional methods has stimulated the third generation of the artificial liver to a return to a hybrid organ applying modern science and technology. A concept of hybrid organs in comparison with organ transplants is introduced. The Japanese national project of developing a new artificial liver system, as conducted by the author as the chairman and his associates, is introduced.  相似文献   
55.
讨论了基于HART协议智能设备的实时管理系统,介绍了HART协议的基本规范,以及如何利用已有集散控制系统(DCS)和工厂信息网络的集成实现实时信息共享,取得了良好的实际效果。  相似文献   
56.
Extracorporeal life support (ECLS) is an essential component of a modern congenital cardiac surgery program. The circuit components and bedside management team may, however, vary among institutions. Here, we evaluate our initial experience with a modified ventricular assist device—based ECLS circuit primarily managed by the bedside nurse. We hypothesize that our outcomes are comparable to Extracorporeal Life Support Organization (ELSO) registry data. All patients who received ECLS from January 1, 2016 to December 31, 2019 at a single institution were included. Primary outcomes were survival to ECLS decannulation and discharge or transfer. Secondary outcomes included complications from ECLS. Data were compared to available ELSO registry data. Thirty‐seven patients underwent 44 ECLS runs during the study period. Forty percent of patients had single ventricle physiology. Nearly 46% of patients received ECLS as part of extracorporeal cardiopulmonary resuscitation (eCPR). Survival to ECLS decannulation (68.2%) and survival to discharge or transfer (61.4%) did not differ from overall ELSO outcomes (69.7%, P = .870 and 50.7%, P = .136), as well as survival to discharge or transfer in a comparable cohort of ELSO centers (53.1%, P = .081). Patients with complications had a lower rate of survival to discharge or transfer but this did not reach statistical significance (47.7% vs. 75.0%, P = .455). Neurologic (50.0%), hemorrhagic (45.5%), and renal complications (31.8%) were most common in this cohort. A modified ventricular assist device‐based ECLS circuit with primary management by the bedside nurse can provide comparable support in a neonatal and pediatric cardiac surgery population. Cost analyses and further delineation of the complication profile are necessary for a complete characterization of this system.  相似文献   
57.
Percutaneous occlusion of the left atrial appendage is increasingly being used as an alternative for stroke prevention in patients with non‐valvular atrial fibrillation at high risk of complications from long term anticoagulation. We describe a case of left atrial appendage perforation during Watchman device implantation requiring emergency repair of the left atrium using sternotomy and cardiopulmonary bypass. Technical considerations for surgical decision making are discussed; in hemodynamically unstable patients as well as those at high risk for embolization.  相似文献   
58.
PurposeAssessing surgical accuracy and patient-recorded outcome measures for patients fitted with either the OPTY-LINE intramedullary realignment system or the Tomofix plate for medial opening wedge high tibial osteotomy (HTO).Patients and methodsTwo matched case series of patients with symptomatic medial compartment osteoarthritis without other significant knee pathology. One group comprised of 19 patients receiving the Tomofix plate, whereas another comprised of 12 patients receiving the OPTY-LINE intramedullary nail. Patella-centred long leg alignment radiographs were assessed to calculate surgical accuracy in all cases. Patients completed knee injury osteoarthritis outcome scores (KOOS) and osteotomy surgery patient satisfaction questionnaires pre-operatively and at 24 months post-surgery.ResultsAbsolute surgical accuracy at 2 years post-surgery was a mean 4.2 [standard deviation 3.7] for OPTY-LINE versus 9.2 [SD 7.8] for Tomofix (p = 0.11, Mann–Whitney U test). On average, patients in either the OPTY-LINE or Tomofix cohort reported at least a minimal perceptible clinical improvement—minimum average improvement of 15—for all five KOOS themes. No significant difference in change of KOOS scores over time or patient satisfaction levels were observed between the two cohorts.ConclusionThe OPTY-LINE device for HTO performs to a similar level as the Tomofix device. Surgical accuracy data are promising for OPTY-LINE, but does not seem to readily translate into difference in patient-reported outcomes compared to Tomofix. Even longer follow-up periods, to measure survival rates, and true randomised trials on larger samples can elucidate if there is a benefit for using one device over the other.  相似文献   
59.
IntroductionAbdominal surgery uses various energy devices for vessel sealing, tissue dissection, and detachment. Currently, Acrosurg Revo® (Nikkiso Co., Ltd., Tokyo, Japan), a novel energy device using microwaves, has been developed for use in laparoscopic surgery. This report describes the early clinical experience of using this device in two cases of laparoscopic surgery.Presentation of caseCase 1 was of a 64-year-old woman who underwent laparoscopic abdominal incisional hernia repair. Case 2 was of a 56-year-old man with a diagnosis of ascending and sigmoid colon cancer who underwent laparoscopic right hemicolectomy and sigmoid colectomy with D3 dissection. Each surgery was completed using Acrosurg Revo® and an endoscopic electrosurgical unit. The postoperative course was uneventful, and both patients were discharged from the hospital without any complications.DiscussionWith this new and novel device, vessel sealing, hemostasis, coagulation, tissue dissection, and detachment were all possible. Notably, there was no spark or mist that hindered the surgical field of view. Furthermore, because microwave coagulation did not result in tissue carbonization, there was a considerable decrease in device tip contamination.ConclusionThe Acrosurg Revo® may be a useful energy device for laparoscopic surgery.  相似文献   
60.
Summary 15 biopsies of dilated and hypertrophied human left ventricles in mitral insufficient hearts were morphometrically investigated. On light and electron microscopical level the results were compared with those received from normally loaded human left ventricles and from hypertrophied human left ventricles found in hearts with aortic valve disease. The results demonstrate alterations when compared with the results from normally loaded left ventricles. The differences between normally loaded and volume loaded left ventricles are smaller than those in pressure loaded left ventricles from aortic valve diseased hearts.This work was supported gratefully by the Deutsche Forschungsgemeinschaft, SFB 104  相似文献   
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