The American journal of medicine
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Adenosine has recently become widely available for the treatment of paroxysmal supraventricular tachycardia. In order to evaluate its role in the management of arrhythmias, we have reviewed the literature on the cellular mechanisms, metabolism, potential for adverse effects, and clinical experience of the efficacy and safety of intravenous adenosine. Adenosine produces transient atrioventricular nodal block when injected as an intravenous bolus. ⋯ Immediate electrical cardioversion is indicated if the arrhythmia is associated with hemodynamic collapse. Adenosine is the preferred drug in those patients in whom verapamil has failed or may cause adverse effects, such as those with heart failure or wide-complex tachycardia. The safety profile of adenosine suggests that it should be the drug of first choice for the treatment of supraventricular tachycardia, but only limited comparative data to support this view are available at present.
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Esophageal pain is transmitted via the sympathetic nervous system to the spinal cord, in which pain from visceral and somatic sources ascends to higher centers in the brain. Primary afferent neurons are bipolar, with the peripheral end specialized to be a sensory receptor. Nociceptors of somatosensory afferents are free nerve endings that can be activated by mechanical, thermal, or chemical stimuli. ⋯ Organ-specific pathways in the brain have yet to be defined, but neuroanatomic tracing techniques employing neurotropic viruses are being developed. The perception of pain can be influenced at multiple levels, such as the receptor in the esophagus, the synapses in the dorsal horn of the spinal cord or thalamus, or the cortex. A fundamental mechanism of modulating nociception is descending inhibition.(ABSTRACT TRUNCATED AT 400 WORDS)
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To review the current data regarding the use of beta-adrenergic blockers for the treatment of congestive heart failure. ⋯ As current data suggest, beta-blockers improve ventricular function and reduce neurohormonal activation in heart failure. beta-blockers should be considered as adjunctive therapy in patients with congestive heart failure. In addition, future studies are warranted to better elucidate their effects on ventricular function and survival.
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Aortoesophageal fistula (AEF) is a relatively rare but life-threatening cause of upper gastro-intestinal bleeding. The clinical characteristics of AEF are so unique that a presumptive bedside diagnosis can be made at the time of presentation. ⋯ We summarize our findings with respect to the etiology and clinical characteristics of AEF. Further, we discuss the diagnostic modalities that may be used to confirm the diagnosis, and the therapeutic modalities available to slow the hemorrhage, so as to allow time to correct the anatomic defect.
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In minorities, as in the general population, hypertension is taken seriously because it is a risk factor for cardiovascular disease. Until recently, our understanding of the role that hypertension plays in the heart disease seen in minorities has been limited by a paucity of prospective data regarding the prevalence, natural history, and pathophysiology of the disease process in minority populations. In the last few years large-scale epidemiologic studies and well-controlled clinical studies alike have confirmed usually high rates of hypertension-related morbidity and mortality in minorities, particularly blacks and Hispanics. ⋯ Inner-city patients are, increasingly, black and Hispanic patients, and these patients are more likely to be underinsured or uninsured, to be functionally illiterate in English, to be disinclined to seek health care, and to be less capable of following a prescribed regimen than the populace as a whole. The nature of the therapeutic regimen itself is probably the most important determinant of compliance, and compliance with drug therapy will be improved if the clinic chooses a simplified drug regimen and avoids drugs that produce intolerable side effects. Once-a-day--or, with transdermal clonidine, one-a-week--single-drug therapy may not be possible in all patients, but multiple drug therapy and multiple daily dosing schedules should be avoided wherever possible.