American heart journal
-
American heart journal · Apr 1994
ReviewThe role of pacing for the management of neurally mediated syncope: carotid sinus syndrome and vasovagal syncope.
The role of permanent cardiac pacing for the management of neurocardiogenic syncope is controversial; however, it does have a secondary role in appropriately selected individuals. Neurocardiogenic syncope includes vaso-vagal and enhanced antagonism of sympathetic-parasympathetic mechanisms. Differentiation of the so-called cardiac inhibitory, vasodepressor, and mixed forms of these disorders is frequently misleading when establishment of effective treatment strategies is attempted. ⋯ Syncopal patients with carotid sinus hypersensitivity or vasovagal responses that include marked bradycardia and loss of atrioventricular synchrony can be supported by dual-chamber cardiac pacing in combination with other therapeutic interventions that diminish the severity of the reflex response. The conditions of patients with carotid sinus syndrome and carotid sinus hypersensitivity are frequently improved with cardiac pacing, and the conditions of elderly patients with vasovagal syncope are commonly improved with artificial pacing. The classic younger patient with malignant vasovagal syncope derives less benefit from artificial pacing; however, in carefully selected persons dual-chamber pacing combined with drug therapy and education decreases syncopal episodes and permits a return to normal activities.
-
American heart journal · Feb 1994
ReviewInterposed abdominal compression as an adjunct to cardiopulmonary resuscitation.
The addition of IAC to otherwise standard CPR provides for the application of external pressure over the abdomen in counterpoint to the rhythm of chest compression. Interposed abdominal compression is a simple manual technique that can supplement the use of adrenergic drugs to increase both coronary perfusion pressure and total blood flow during CPR. Mechanistically, manual abdominal compressions induce both central aortic and central venous pressure pulses. ⋯ The incidence of abdominal trauma, regurgitation, or other complications is not increased by IAC. Recently, randomized trials have shown that short-term and long-term survival of patients resuscitated in the hospital by IAC-CPR are about twice that of control patients resuscitated by standard CPR. The technique of IAC has thus evolved to become a highly promising adjunct to normal CPR, which is likely to be implemented in an increasing number of clinical protocols in the 1990s.
-
American heart journal · Oct 1993
ReviewInnovative emergency defibrillation methods for refractory ventricular fibrillation in a variety of hospital settings.
This article reviews the ability of innovative rescue defibrillation techniques for the treatment of refractory ventricular fibrillation. These data were obtained in a variety of hospital settings at the University of California, San Francisco, from 1986 to 1992. Innovative rescue defibrillation techniques were applied to 15 patients with refractory ventricular fibrillation having failed > or = 2 high-energy transthoracic shocks in a variety of hospital settings. ⋯ Transesophageal defibrillation performed after 50 minutes of cardiac arrest successfully terminated ventricular fibrillation in each patient. Thus alternative methods now exist that permit rescue defibrillation in a variety of hospital emergency settings. These techniques are performed with simple-to-use equipment that is compatible with standard defibrillators.
-
American heart journal · Oct 1993
ReviewThe role of the coronary collateral circulation in limiting myocardial ischemia and infarct size.
The role of coronary collateral circulation in limiting ischemia and infarction has been studied prospectively. Transient occlusion of a coronary artery angioplasty has provided evidence that collateral circulation decreases wall motion abnormalities, ST segment changes, and lactate production. ⋯ Although collateral flow may decrease coronary artery bypass graft patency in certain subgroups of patients, the perioperative infarct rate and mortality is decreased. Growth factors have been identified that increase the development collateral circulation and may improve ventricular function in the setting of myocardial infarction.
-
American heart journal · Jun 1993
ReviewDeep hypothermic circulatory arrest during cardiac surgery: effects on cerebral blood flow and cerebral oxygenation in children.
Deep hypothermic circulatory arrest has become an essential technique to allow repair of complex congenital cardiac lesions in children. The arrested state has concerned the surgeon, cardiologist, and anesthesiologist alike, and yet deep hypothermic circulatory arrest has been highly successful with a low incidence of neurologic sequelae. ⋯ That the hypothermic arrested brain likely becomes anoxic and recovery of the anoxic brain depends in large part on recirculatory hemodynamics suggests that the lack of hyperemia and hyperoxia may play more major roles than was previously believed. The mechanism of protection may be related to suppression of oxygen free radicals.