ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Congestive heart failure is a common clinical problem resulting in significant morbidity and mortality. Although considerable progress has been made in elucidating the pathophysiologic mechanisms that lead to the development of this process, much remains unknown. The techniques of modern molecular biology now allow a detailed and systematic analysis of this disease. Recent data linking cardiac hypertrophy, aberrant signaling, or cytoskeletal abnormalities to the development of heart failure have provided new insights into this process. These studies have confirmed the importance of many classical pathways but also revealed novel pathways. This review will focus on the recent advances that have been made and will highlight the importance they have had in our understanding and treatment of heart failure.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Endothelin-1 has been appreciated in animals and humans as a potential target for inhibition in patients with acutely decompensated congestive heart failure (CHF), as well as patients with a chronic low-output state. There has been intense interest in determining the effects of endothelin-1 on the cardiovascular system. Elevated plasma levels of endothelin-1 in patients with CHF portend a poorer prognosis than similar patients without elevated levels. Endothelin-1 levels correlate inversely with maximum oxygen consumption, and inhibition of the myocardial endothelin pathway in rats with CHF improves survival. An association between endothelin-1 and the development of CHF has recently been supported. Selectively inhibiting the endothelin A receptors in dogs with CHF produced hemodynamic improvement. Similarly, in rabbits, a structural advantage was demonstrated. Benefits in cardiac remodeling have been demonstrated in several models of CHF by nonselectively antagonizing endothelin receptors. In human trials using nonselective endothelin-1 inhibitors, researchers have demonstrated hemodynamic benefit and improvement in cardiac function in patients with decompensated CHF. Inhibition of endothelin-1 in patients with CHF appears to have potential therapeutic value, and ongoing clinical trials will further investigate the safety, efficacy, and role of this new potential therapeutic target for the treatment of CHF.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The renin angiotensin system was first described over 100 years ago and is still the focus of intense clinical and basic science investigation. The renin angiotensin system was demonstrated to play a major pathogenetic role in hypertension. The development of inhibitors of angiotensin-converting enzyme and specific receptor blockers for angiotensin-II represent a major advance in the treatment of elevated blood pressure. However, the renin angiotensin system is intimately involved in a number of conditions that increase the risk for atherosclerosis. Components of the renin angiotensin system have demonstrated to play a significant role in the initial phases of atherosclerosis. Additionally, plaque vulnerability and the potential for an acute atherosclerotic event are also modulated by the renin angiotensin system. Angiotensin-II plays a significant role in the balance between intravascular clot formation and fibrinolytic potential. Therefore, blocking the generation of angiotensin-II or inhibiting its binding to specific receptors may decrease the subsequent risk for unstable angina and acute myocardial infarction. Increased renin activity has been correlated as a statistical risk factor for coronary heart disease and converting enzyme inhibition has been demonstrated to decrease the incidence of acute ischemic events. This review will center on the role of modulation of the renin angiotensin system as a means to alter the clinical course of coronary atherosclerosis.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Evaluation of the hemodynamic response in heart failure is a useful adjunct in clinical management. Invasive monitoring has been the accepted gold standard of hemodynamic assessment but carries with it significant associated risks. Noninvasive hemodynamic assessment in heart failure previously has been either unreliable or difficult to obtain. Bioimpedance relies on the proportional change in the conduction of alternating current applied across the thorax as a function of blood volume in the heart and great vessels. Stroke volume, cardiac output, thoracic fluid content, and measures of diastolic function can be determined with bioimpedance. Impedance cardiography is becoming an accepted method for safe, reliable, and reproducible assessment of hemodynamics in heart failure.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Because of the standard use of oral neurohumoral antagonists, the role of intravenous agents for advanced heart failure patients has changed profoundly. Their current use as medical therapy is restricted to two indications: first, as short-term infusion (hours to days) in advanced heart failure patients who decompensate into a symptomatic New York Heart Association class IV condition and who are admitted for rapid hemodynamic support with intravenous vasodilators or inotropes; in these patients after hemodynamic and clinical stabilization, optimization of conventional heart failure therapy has to be reconsidered; second, as long-term application in heart transplantation candidates who are in a similar desperate condition although already receiving maximal oral heart failure therapy.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Heart transplantation remains the best hope for patients with end-stage heart failure unresponsive to conventional therapy, but the number of transplant candidates continues to exceed the number of available donor hearts. Despite major advances in the medical management of heart failure, researchers continue to explore alternative surgical therapies designed to augment cardiac function. Many of these surgical therapies are still in the experimental or clinical trial phases. Surgical approaches include coronary revascularization, mitral valve repair or replacement, cardiomyoplasty, left ventricular volume reduction surgery, and bridging to recovery with the use of ventricular assist devices. Although cardiac surgeons have gained considerable experience in the treatment of patients with heart failure, many improvements and innovations lie ahead.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

A miniaturized axial flow pump to provide left ventricular assistance has been developed. Such a device has the potential to address limitations of the larger pulsatile devices. Clinical trials of the MicroMed DeBakey VAD (ventricular assist device) began in Europe in November 1998. As of December 1, 1999, 18 patients have been implanted with the MicroMed DeBakey VAD. Hemodynamic evaluations along with blood chemistry analysis were recorded routinely. Exercise tolerance was observed. In most patients, end-organ function has improved and has not deteriorated in any patient. Patients have been able to perform normal low-level activity and have tolerated positional changes without evidence of postural hemodynamic changes. Select patients have taken supervised out-of-hospital excursions. This initial clinical experience with the MicroMed DeBakey VAD suggests that the miniaturized axial flow pump can provide ventricular support to bridge patients to cardiac transplant and may provide an improved quality of life for the end-stage heart failure recipient.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The past decade has witnessed significant advancements in the treatment of patients with refractory symptoms due to hypertrophic obstructive cardiomyopathy. In this publication, we will review the impact of dual-chamber pacing and nonsurgical septal reduction therapy with ethanol on the outcome of these patients. Both therapies have been shown to result in significant reductions in the left ventricular outflow gradient, which was an entry criterion in all the reported studies, along with symptomatic relief from symptoms of angina and dyspnea on midterm follow-up. Studies currently are under way to compare dual-chamber pacing and nonsurgical septal reduction therapy with myotomy-myomectomy, which is considered to be the standard of care in these patients.

ISSN:0268-4705    

出版商:OVID    

年代:2000

数据来源: OVID