With improvements in technology, the indications for pacing have been gradually expanding. In general, patients who develop symptoms and/or signs of hypoperfusion of critical organs or organ systems because of bradycardia, or an inadequate increase in heart rate during exertion or some other stress, may benefit from pacing. Many of these patients have evidence of intrinsic conduction-system disease as well as significant organic heart disease, although often the relationship between the etiology of the heart disease and conduction abnormalities is unclear. For example, most patients who require pacemakers for symptomatic atrioventricular conduction disease have underlying coronary-artery disease (CAD). In many cases, however, heart block did not develop in the setting of acute myocardial infarction (MI), and post-mortem examination of the conduction system shows nonspecific degeneration, rather than ischemic necrosis. Recently, there has been a growing interest in the use of pacing techniques in patients who are not necessarily bradycardic—such as congestive heart failure (CHF), or hypertrophic cardiomyopathy. Although the indications for pacing in these areas are still evolving, the clinical characteristics of the targeted patients may be markedly different from those of traditional pacemaker populations. Currently, it is estimated that greater than 85% of the more than one million individuals in the United States with permanent pacemakers are older than 65 yr of age (2). Almost one-half of these devices have been implanted because of some type of sinus-node dysfunction (3). The majority of implanted pacemakers are dual-chamber devices, and most have rate-responsive capabilities (2). It is anticipated that these statistics may become considerably different as the indications for permanent pacing continue to grow and evolve.

Your Heart and Nutrition

Your Heart and Nutrition

Prevention is better than a cure. Learn how to cherish your heart by taking the necessary means to keep it pumping healthily and steadily through your life.

Get My Free Ebook

Post a comment