The use of technology in heart disease has developed rapidly in the past 50 years. In recent years, devices have become small, compact, reliable, implantable, manipulated without extensive intervention, multiprogrammable, powered by a sophisticated source, and serviced through a link with computer software. Technology has developed so rapidly that it is hard to believe that even as early as 10 years ago, most of the technology that will be discussed in this issue of The Journal of Cardiovascular Nursing (16:3) was not available, even in a crude or noncommercial form.
In the early days of cardiac technology, many devices carried warnings and there was great concern about using and maintaining them in nonemergent settings. Nurses invested much time, effort, and skill in learning and maintaining safe practice and a safe environment. Because many devices were "manual," nurses were expected to be ever vigilant in optimizing settings and ensuring the welfare of their patients. Through computerization and built-in device algorithms, we have come a long way and do not need to have the same level of vigilance in device maintenance. This is good for patients, because it means that many of these devices can be portable and used in the outpatient setting. We should remember, though, that newer devices are expensive and may be accompanied by physical or psychologic risks. In other words, they may not be for everyone.
So, in reading the articles found in this issue, keep in mind that there is still much to consider regarding cardiac technology. The rapid and extraordinary development of technology provides tools that were once experimental and are now routine. Consider that pacemaker generators were externally carried on carts in the early years before a fully transistorized device was developed (imagine the quality of life with that device in place). In the 1980s and earlier, the word "defibrillation" led one to envision the following series of steps, carried out in a quick and efficient manner by trained nurse clinician, medical, and paramedical professionals: lugging a large machine to the site of action, taking time to adhere pads to the chest or gel to the paddles, setting up the machine parameters, and then, finally, carrying out the actual steps of defibrillation. Today, biventricular pacemakers have come to market, internal cardioverter defibrillators (ICD) are commonplace, and external "wearable" defibrillators are in clinical trials. All are examples of the new dimensions of the practice of cardiology that build on the past.
New technology means new options for patients with heart disease. There is much to talk about in this arena, but as this issue is limited in space, the focus of this issue will be on technology in patients with acute coronary syndromes, electrophysiology issues, including sudden cardiac arrest, and heart failure. There are many advances going on in all branches of cardiology (electrophysiology, intervention-catheterization laboratory, preventive cardiology, clinical cardiology, heart failure, and molecular cardiology [genetics]). Although this issue is not a comprehensive overview of new technology and does not contain genetics-based technology for diagnosis and treatment, the articles presented discuss significant advances that provide exciting options for cardiac patients and that are credited with saving hundreds of thousands of lives.
The article by Stryer provides a fascinating description of two new software programs that use a logistic regression model to compute a patient's probability of having acute ischemia and a patient's outcome if fibrinolytics are used in acute myocardial infarction. Both decision-support instruments can positively affect patient outcomes if used proactively when making treatment decisions. In addition, they can both be used retrospectively to determine the need for quality improvement in this patient population. Because rapid effective triage and treatment are integral components of emergency care for patients with acute myocardial infarction, tools that reduce time to treatment and ultimately improve coronary blood flow are not only convenient but may be essential in improving diagnosis accuracy and facilitating administration of fibrinolytic drugs. Although there are other newly devised risk index tools available that are predictors of mortality or early postmyocardial events,1 these instruments require information that is often not easy to discern because of the variety of patient presentations in acute coronary ischemia and the many potential risk factors for events after fibrinolysis. Clinical implications of the technology described in this article are improved diagnosis, treatment time, and ultimately patient outcomes, and, fortunately, this software technology can be added to current computer systems and put into practice without much human resource time and effort.
The second article, by Housholder-Hughes, focuses on the recent revisions in advanced cardiac life support (ACLS); the clinical implications are the same as above: improved diagnosis, improved treatment time, and improved patient outcomes. However, those implications only hold true if ACLS concepts and guidelines are implemented as directed. This article provides a great overview of current recommendations and the rationale for changes made. Now, it is up to health care professionals to take the time, effort, and cost to train users properly by providing both cognitive and psychomotor learning experiences. In addition, nursing and medical leaders must be willing to ensure that systems are in place (the right technology, supplies, medications; the right users; and the right performance improvement monitoring systems) so that the stated clinical implications can be achieved and advanced. In addition, policy development may be crucial to the successful use and enforcement of these new standards.
The next two articles by Futterman and Lemberg and Stahl and Richards provide details of technologies that afford nontraditional services for the debilitating problems of syncope and advanced heart failure symptoms, respectively. Determining the cause of syncope can be difficult at best because it is hard to predict when it might naturally happen and trying to induce it in a controlled setting is not always successful. In addition, patients and families suffer from the emotional stress associated with "not knowing" when it might happen, why it happens, and also what the results might be. Futterman and Lemberg explore common etiologies of syncope, discuss traditional diagnostic measures, and provide details of a subcutaneously implanted loop recorder (an intermittent ambulatory electrocardiographic [ECG] monitor) that has been designed for long-term use when symptoms or ECG events occur infrequently. This leadless technology allows patients freedom to carry out daily activities. More importantly, the diagnostic yield was significantly better than standard diagnostic evaluation procedures, making it a cost-effective tool in the evaluation of syncope. This is certainly one example in which technology developers should be credited for allowing patients to remain ambulatory while trying to determine the elusive nature of syncope. Ultimately, this device might prove not only to be better clinically, but it might provide cost benefits over traditional diagnostic measures. Earlier diagnosis of the problem might relieve psychologic stress as well.
The advancements in LVAD design and function in recent years is truly amazing. These invasive devices offer patients with end-stage heart failure relief from chronic debilitating symptoms and improvement in quality of life when pharmacologic therapies are ineffective. Research with these devices is ongoing, and issues associated with the high frequency of serious adverse events (infection, bleeding, and mechanical failure) will need to be addressed further. When inserted before end-organ dysfunction occurs, patients have shown improvement in many variables. The findings of the REMATCH study were recently reported in the New England Journal of Medicine.2 In this study, patients who were not candidates for transplantation were randomized to medical therapy or LVAD. Both groups experienced a high rate of mortality; however, the LVAD group clearly benefited from improved survival in all time points throughout the 2-year study period and also demonstrated improved activity level and decreased symptoms. These findings may spur a growth in the use of LVAD devices. Stahl and Richards' article provides valuable information in a step-by-step format on developing and maintaining a training and competency program. Nurses are pivotal to the success of an LVAD program, and this article provides detailed rationale for decisions made by the team to ensure nurses are adequately prepared for their role.
The next two articles, by Schott and by White, focus on sudden cardiac death. The clinical cardiac electrophysiology subspecialty has undergone radical transformation in recent years. We have a much better understanding of ion channel disturbances and have developed devices to diagnose, treat, and alleviate cardiac dysrhythmias. Sudden cardiac death continues to increase as a cause of death, in part because of the increased incidence of heart failure and the aging population. Thus, discussion of this topic is timely and imperative. In February 2001, ICD consensus recommendations were published that discussed indications, guidelines for use, and recommendations for follow-up3; however, the "indications" section of this guideline might already be outdated because the MADIT-II trial (postmyocardial infarction patients with ejection fraction <35%, treated conventionally or with ICD but without electrophysiology testing done before implant) was recently stopped early by the Data Safety Monitoring Board because of statistically significant improvement in outcomes in the ICD group. The results of MADIT-II might lead to an explosion of ICD implants in the ischemic cardiomyopathy (ICM) heart failure population that will result in a greater need to reassess psychologic and social factors of potential implantees. In addition, the need for temporary "wearable" devices might surge in popularity, especially in patients after myocardial infarction without heart failure or in advanced heart failure while waiting for transplantation.
The article by Schott provides a review of an automated, external, wearable defibrillator that is still in clinical trials. This device has the potential to improve the probability of surviving sudden cardiac death and provides patients with a level of control over their situation. Although it is too soon yet to know whether patient control is a good thing, this device provides another link in the "chain of survival," and hopefully, further research will determine whether this device is an essential link in the chain.
White's article focuses on the psychologic and social impact of ICDs on the lives of patients and their families. An ICD saves lives, but at what cost? For some, the trade-off of life with ICD shocks is worth the discomfort, but clearly, White's review of the literature indicates that this is not always the case. White's article reminds us that we must look beyond life itself to quality of life and what has meaning for our patients. We must also remember that the defining features of quality of life are individualized and that we must assertively explore these concepts with our patients both before and after ICD insertion. If ICD popularity and the indications for use change based on the MADIT-II trial, then nurses must be proactive in developing multiple systems to address psychosocial issues. The development, study of, and publishing of an algorithm that focuses on psychologic/psychosocial care priorities would be a welcome addition to nursing.
In the last three articles, we turn to new technology that has been targeted for use in patients with heart failure. Hemodynamic guided therapy via pulmonary artery catheter has been in and out of vogue over the years because of cost (of the invasive procedure and the critical care stay) and potential morbidity. In addition, we have learned that cardiac index level does not provide information about prognosis. But we do know that left ventricular preload and afterload values are meaningful and difficult to ascertain by physical examination. Von Rueden's article provides information about two new propositions: an implantable hemodynamic monitor for outpatient use and a noninvasive hemodynamic monitor that can be used in a variety of health care settings. We have much to learn about the value of and how to best use these devices in clinical settings. Although these devices might help with compliance and vigilance monitoring and provide early warning of heart failure decompensation, we still must learn the absolute cost of the technology and make certain that their use truly leads to improved outcomes.
Cardiac resynchronization therapy (CRT) is a new term that has been born from the development of biventricular pacemakers. Legge and Leeper's article discusses this new technology in detail. Unlike most therapies for heart failure, the biventricular pacer works independently of the patient's compliance level with medications and lifestyle changes. Although it is new and exciting and one company's device has recently been approved by the Food and Drug Administration (FDA) for use, more research is necessary to determine the ideal candidate for this expensive technology. With recent FDA approval, if it is used indiscriminately, we run the risk of losing the benefits that have been shown in early studies. Nursing must be proactive in developing patient education materials that include this technology and also must conduct research on how attention to lifestyle modification can affect clinical outcomes when this device is in place.
In the final article, by Hoercher, Vacha, and McCarthy, we turn to surgical approaches in management of heart failure. This article provides a wonderful overview of one surgical procedure and one device, both of which were developed after reviewing results of past surgical ventures in management of heart failure. The "wrap" device is a progression of the cardiomyoplasty procedure (performed in the mid 1980s to late 1990s but never went beyond clinical trials). The "splint" is founded on the Law of LaPlace and the idea that if wall stress is reduced, left ventricular remodeling progression is also reduced and may even be reversed. In light of the growing incidence and prevalence of heart failure and the lack of availability of donor hearts, these novel approaches in management are welcome additions. If clinical studies prove they are advantageous, they will provide new hope to patients for an improved quality and length of life.
-Nancy M. Albert, MSN, RN, CCNS, CCRN, CNA
Clinical Investigations Unit
Department of Thoracic and Cardiovascular Surgery
Heart Failure Disease Management Programs
George M. and Linda H. Kaufman Center for Heart Failure
The Cleveland Clinic Foundation