ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Although heart rate variability has long been recognized as clinically important in fetal monitoring and the assessment of autonomic neuropathy, recent advances in data processing have increased its usefulness as a tool. Basic scientists are using the study of heart rate variability to elucidate the neural control mechanisms of the heart, whereas clinicians are using the same methods to look at the effects of disease states and medical interventions on the heart. In particular, heart rate variability can give insight into the relative sympathetic and parasympathetic inflow to the heart. Because the techniques involved in heart rate variability analysis are relatively new, much work is being done to determine the most effective way to extract information from the beat-to-beat fluctuations in heart rate.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Amiodarone and sotalol are class III antiarryhythmic drugs that block membrane potassium channels, and have been available for many years. Newer class III antiarrhythmic drugs are now being developed, because they could circumvent several of the problems found with the more widely used class I, or sodium channel-blocking drugs. Class III drugs can be arrhythmogenic, but they might cause fewer arrhythmias than sodium channel-blocking drugs. As they do not affect the sodium channel, it is possible that they could have smaller effects on conduction velocity and contractility. For these reasons, class III drugs likely will assume an important role in the treatment of perioperative arrhythmias.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Beta-adrenoceptor desensitization (loss of response) and down-regulation (loss of receptors) are a consequence of an increased activity of the sympathetic nervous system in the failing human heart. In some heart diseases β1adrenoceptors are selectively decreased, whereas others seem to be characterized by a reduction of both β1and β2subtypes. Changes in messenger RNA levels for the β1sybtype and the β-adrenoceptor kinase, an enzyme that phosphorylates β adrenoceptors resulting in receptor uncoupling, appear to be significant in the desensitization and down-regulation in the failing heart. Angiotensin-converting enzyme inhibitors have beneficial effects in the therapy of heart failure. Beta-adrenoceptor antagonists are potentially another class of agents that could improve cardiac function.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

In this review, we consider the main pathophysiological processes involved in ischaemia and reperfusion injury and stunning. Mechanisms involved are low-energy state, intracellular sodium and calcium overload, damage due to increased production of free radicals, and dysfunction in the excitation-contraction coupling process. These different pathophysiological mechanisms, and the fascinating phenomenon of ischaemic preconditioning that renders the heart resistant to ischaemia after brief periods of ischaemia, lead to therapeutic possibilities for myocardial protection. New developments in myocardial protection through administration of cardioplegia, prevention of myocardial oedema, uncoupling of excitation-contraction, inhibition of adenosine and nucleoside transport, and Na+-H+exchange, and antioxidant therapy are discussed.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

This review focuses on three areas related to the extension of good quality life in patients with end-stage heart disease. First, methods of improving the donor pool by improving the quality and supply of donor organs are judged acceptable. The second part of the review deals with alternative means of life support using mechanical asist devices or biological assist with cardiomyoplasty. The final section covers certain advances in our knowledge which may reduce early graft failure. In addition, there is a discussion of novel approaches to reducing the damaging effects of immunosuppression.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Blood conservation during cardiac surgery is an area of considerable investigation and interest. Strategies that may decrease allogenic blood product exposure during cardiac surgical procedures are reviewed. The two strategies which were judged to be the most efficacious in reducing blood product exposure were autologous predonation and the use of aprotinin. Additional measures which favorably impact on blood product exposure are the use of recombinant human erythropoietin to enhance autologous blood donation, selective use of desmopressin acetate, salvage of the bypass circuit, the use of on-site laboratory testing and the establishment of transfusion guidelines based upon laboratory values. All other currently used strategies are either uner investigation, marginal in benefit, or unfounded.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Of the pharmacologic hemoconservation strategies which decrease blood loss and allogeneic blood transfusion after cardiac surgery, aprotinin, epsilon aminocaproic acid, and tranexamic acid are effective prophylactic agents which have been the subject of recent interest. Their mechanism of action is explained by the interaction of the contact activation, fibrinolytic, and inflammatory systems with platelets that occurs during clinical cardiopulmonary bypass. Desmopressin acetate has limited demonstrated efficacy. Nafamostate mesilate and platelet glycoprotein IIb/IIIa receptor antagonists are potential hemoconservation agents under investigation. When excessive bleeding occurs after cardiopulmonary bypass, treatment selection on the basis of immediately available results of coagulation testing restores hemostatic function more effectively than empiric therapy chosen before conventional laboratory test results are known. Simple bedside coagulation monitors can provide this rapid diagnostic information. Thromboelastography may predict excessive bleeding but the diagnostic and therapeutic roles of this test are not yet defined.

ISSN:0952-7907    

出版商:OVID    

年代:1995

数据来源: OVID