The Heart Failure Society of America (HFSA; Minneapolis) last month issued its new guidelines for “living with and treating” heart failure (HF), and in so doing promised the expansion of recommendations concerning the use of medical devices to treat HF. The lengthy list of protocols does provide greater focus on devices than in the organization’s guidelines last issued in 1999 – but probably not as much as device manufacturers in this sector would like.
The guidelines issued six years ago – and currently still available on the HFSA web site (www.hfsa.com) – have a fairly narrow focus: primarily pharmacological approaches for treating heart failure caused by left ventricular dysfunction. Compared to the emphasis on drugs, the presence of device therapy recommendations in the 1999 document is slender indeed; in 26 pages of single-spaced verbiage, the document provides just one section dealing with devices, lumping these also with pharmacology in a section titled “Antiarrhythmic Drug and Device Therapy.” Additionally, this section offers essentially only one recommendation, and one paragraph of supportive background information, for the use of implantable cardiac defibrillators (ICDs).
The recommendation is for use of ICDs in “patients with heart failure who have been resuscitated from primary ventricular fibrillation or who have experienced hemodynamically destabilizing sustained ventricular tachycardia.” As background it refers to the MADIT, AVID, CIDS and CASH trials, saying that they “indicate that survival of patients with life-threatening arrhythmias is improved with ICD placement compared with antiarrhythmic therapy.” And it notes the lack of completed trials (as of 1999) for use of ICD therapy “specifically” in HF patients and the need for such data – the apparent rationale for the limited recommendations for device use.
More than six years and many trials later, and much more overall experience in all phases of HF therapy, the new guidelines are titled “HFSA 2006 Comprehensive Heart Failure Practice Guideline” and are indeed more comprehensive than the 1999 offering.
Extending to nearly 60 pages, the new protocols this time provide somewhat more than two pages of recommendations and “considerations” for the use of ICDs and other “electrophysiologic interventions.” And an introductory statement says that “Perhaps no area of HF therapy has changed more in recent years than the use of implanted devices as a treatment option.”
Following are some of the main recommendations provided for use of devices (which come also with a “strength of evidence” rating indicating their importance, from A to C).
Under “Disease management program”:
• “Consideration of assist devices as destination therapy,” (C); and also as “end-of-life care” that “Inactivation of an implantable defibrillation device should be discussed” (C).
Under “General Considerations,” primarily focusing on ICDs:
• Prophylactic use of ICDs “In patients with or without concomitant coronary artery disease” (B); “for those with mild to moderate HF symptoms” (A); “concomitant placement “in patients undergoing implantation of a biventricular pacing device” (B); “for survivors of cardiac arrest from ventricular fibrillation to hemodynaically unstable sustained ventricular tachycardia without evidence of acute [myocardial infarction] or if the event occurs more than 48 hours after the onset of infarction in the absence of a recurrent ischemic event” (A).
• Biventricular pacing therapy for “selected ambulatory NYHA [Class] IV patients may be considered” (B)
Under a section on heart transplantation, primarily focused on “mechanical support devices:
• Patients awaiting heart transplantation who have become refractory to all means of medical circulatory support should be considered for a mechanical support device as a bridge to transplant” (B).
• “Permanent mechanical assistance using an implantable assist device may be considered in highly selected patients with severe HF refractory to conventional therapy who are not candidates for heart transplantation” (B).
Several recommendations also state those circumstances where ICDs and assist devices are not indicated.
Overall the new guidelines offer a clear advance over the single-paragraph treatment by the 1999 version of the protocols. And the updated guidelines do cover a very much wider spectrum of heart failure issues, beyond the device and heavily drug-weighted recommendations. These range from new considerations about ejection fraction and diet and nutrition to education and counseling for better self-management and the above-mentioned end-of-life protocols.
Clearly, future updates of these protocols will probably come more quickly and expand the role of devices for HF treatment even further.
Framingham now focused on disease genetics
The National Heart, Lung and Blood Institute (NHLBI) of the National Institutes of Health (NIH; Bethesda, Maryland), in collaboration with the Bos-ton University School of Medicine, has reported the launch of a comprehensive genetic research study to identify genes underlying cardiovascular and other chronic diseases. The new research – the Framingham Genetic Research Study – will be part of the NHLBI’s long-running Framingham Heart Study (FHS) that has produced so many insights into cardiovascular disease and therapy. It will involve up to 500,000 genetic analyses of the DNA of 9,000 study participants across three generations.
The NIH’s National Center for Biotechnology Information, part of the National Library of Medicine (Washington), will help develop a study database that will be made available at no cost to investigators, enabling them to search for associations between genes and diseases. NHLBI Director Elizabeth Nabel, MD, said that the study “will take genetic research in the Framingham study to the next level – accelerating discoveries on the causes, prevention, and treatment of major chronic diseases . . . [R]esearchers will be able to obtain more information about the connection between unique genetic variations in DNA and cardiovascular disease risk factors as well as the genetic basis for heart attack, stroke, and other chronic diseases.”
Since 1948, the Framingham Heart Study has studied the health of many of the Massachusetts town’s residents, producing findings regarding the contributions of hypertension, high cholesterol, cigarette smoking and other risk factors to the development of cardiovascular disease. The new study will take advantage of knowledge gained from the Human Genome Project’s sequencing and mapping of all human genes and from the recently completed HapMap Project, which charted the pattern of genetic variation in the human genome. And it will use recently developed technology that now enables rapid genotyping of about 500,000 SNPS in each individual. Computer programs will then help scientists relate these alterations to many of the clinical and laboratory measurements made of study participants during their examinations.
CABG highly varied in Michigan
In a paper published in the journal Circulation, a group of Michigan researchers reports wide variations in the delivery of angioplasty care and outcomes at five hospitals where doctors and nurses received guidance and data to help them improve angioplasty care, as compared to seven hospitals where they did not. The results yielded a stark “before” and “after” contrast. Before the start of the project, the 3,731 patients treated at the five hospitals in one year received widely varying levels of care. Many never received drugs that could help prevent complications during or after their angioplasty, while others received far more than necessary of the blood-thinning drug heparin, or the dye that lets doctors see blockages while they perform the minimally invasive procedure. There also was a wide variation in how patients did afterward, including their risk of kidney damage related to the dye, and their need for emergency heart surgery and blood transfusions.
Five years later, after the quality-improvement project was under way, the 5,901 patients treated at the same five hospitals in that year received better, more uniform care, including higher rates of preventive medication use, less use of heparin and more appropriate amounts of dye. They also did better overall, with lower rates of complications related to their hearts and kidneys. At the seven comparison hospitals, the researchers looked at data from 10,287 patients who had angioplasties during 2002, the same year as the “after” measurements at the five hospitals. They found wide variation in the use of preventive medications, heparin and dye, and higher rates of some complications than at the five other hospitals. All seven hospitals in the comparison group are now part of the quality-improvement project.
ICDs: cost-effective and cost-gaining
Researchers have introduced the concept that the cost of extending life with a defibrillator in young and otherwise healthy subjects with genetic cardiac disorders can be balanced by society gains when the lifespan of an individual is considered. Through computer-based analytical models, the study, published in Annals of Noninvasive Electrocardiology, shows that primary intervention with defibrillator therapy is cost-effective and even cost-gaining in this population.
Ilan Goldenberg, MD, of the Heart Research Follow-Up Program at the University of Rochester Medical Center (Rochester, New York), said, “Data on the yield of this mode of therapy derives mostly from studies of adult patients with acquired cardiac disease. In the present study, we employ an analytical model based on current knowledge of the risks of patients with genetic cardiac disorders and show that in this high-risk population, intervention with a defibrillator at the age of 10 years is cost-effective or even associated with economic gains due to the societal contributions of young and otherwise healthy patients in whom defibrillator therapy extends life.”
Defibrillator therapy was found to be beneficial and cost-effective, with a ratio in the range of $30,000 to $185,000 per quality-adjusted-life-year saved in adult patients with acquired heart disease. In high-risk young males and females with genetic cardiac disorders, implantation of a defibrillator resulted in cost savings in the range of $15,000 to $20,000 for each quality-adjusted-life-year saved.