Acknowledgment

This CME activity is supported by an educational grant from Medtronic, Inc. , Minneapolis, Minnesota.

Disclosures

Dr. Friedewald has received honoraria for speaking from Novartis, East Hanover, New Jersey. Dr. Fonarow has received honoraria for speaking and consulting and research grants from Medtronic; and GlaxoSmithKline, Research Triangle Park, North Carolina. Dr. Olshansky has received honoraria for speaking and consulting from Medtronic; and Boston Scientific Corporation, Natick, Massachusetts. Dr. Olshansky has received honoraria for consulting and is a member of the advisory board for Novartis. Dr. Yancy has no relevant financial relationships to disclose. Dr. Roberts has received honoraria for speaking from Merck, Whitehouse Station, New Jersey; AstraZeneca, Wilmington, Delaware; and Novartis.

Disclosures

Dr. Friedewald has received honoraria for speaking from Novartis, East Hanover, New Jersey. Dr. Fonarow has received honoraria for speaking and consulting and research grants from Medtronic; and GlaxoSmithKline, Research Triangle Park, North Carolina. Dr. Olshansky has received honoraria for speaking and consulting from Medtronic; and Boston Scientific Corporation, Natick, Massachusetts. Dr. Olshansky has received honoraria for consulting and is a member of the advisory board for Novartis. Dr. Yancy has no relevant financial relationships to disclose. Dr. Roberts has received honoraria for speaking from Merck, Whitehouse Station, New Jersey; AstraZeneca, Wilmington, Delaware; and Novartis.

Objectives

Upon completion of the activity, the physician should be able to:

• 1
  

  Diagnose patients with congestive heart failure who are candidates for implantable cardioverter-defibrillator (ICD) therapy.

  
  
• 2
  

  Explain the risks and benefits of ICD therapy to patients.

  
  
• 3
  

  Decrease gender and ethnic disparities in treatment with ICD therapy.

Introduction

The ICD was first placed into human subjects in 1980 by Mirowski, after several years of nonhuman animal testing. In the 30 years since the introduction of ICDs, ICD therapy in the United States has become commonplace, with 2 broad categories of use for preventing sudden cardiac death (SCD): primary prevention involves the prevention of SCD in patients without histories of cardiac arrest or sustained ventricular tachycardia, and secondary prevention involves the prevention of SCD in patients who have survived prior cardiac arrest, sustained ventricular tachycardia, or other major cardiac events. This Editor’s Roundtable focuses on ICD therapy for primary prevention, which mainly involves patients with ischemic and nonischemic heart failure “who are receiving optimal medical therapy and have a reasonable expectation of survival with good functional status for >1 year.”

Discussion

Dr. Friedewald: When did ICD therapy appear?

Dr. Olshansky: ICD therapy was developed and first tested in nonhuman animal models by Michel Mirowski in the 1970s. Although the concept of an ICD was not initially well received, Mirowski paved the way for clinical acceptance when he performed the first human implantation in 1980. The first ICD was large, weighing about 9 oz, with a large battery and a capacitor to shock the heart. It had few settings, its sensing ability was rudimentary, and it lasted only about 18 months. It required major surgery because the device was implanted in the abdomen and the chest had to be opened, requiring at least 1 week of hospitalization. The first ICD devices were handmade, so the supply was limited, and patients sometimes had to wait for weeks before 1 could be obtained. The technology progressed dramatically over the next 30 years as the devices became multiprogrammable, used smaller batteries with longer battery life, had better capabilities to defibrillate with biphasic shocks, were made programmable for cardiac pacing, had better leads that could be placed intravenously, and were implanted into the upper chest, an easy procedure to perform. Today, ICD implantation is a low-risk procedure carried out worldwide.

Dr. Yancy: What are the current risks of ICD use?

Dr. Olshansky: There are several. Although the focus in the lay press has been placed on device recalls and lead problems, improper working devices are rare, maybe 1 in 10,000 implants. Other complications including myocardial lead perforation, infection, pneumothorax, lead dislodgement, and inappropriate shocks (a shock delivered for a reason other than a life-threatening ventricular tachyarrhythmia). The ICD is designed, however, to protect life at the expense of an occasional inappropriate shock. The risk for inappropriate shock is about 25%.

Dr. Yancy: What is the frequency of serious problems with ICDs?

Dr. Olshansky: Serious problems such as infection and device failure occur in about 1% of ICD implants.

Dr. Yancy: What is the current role of the ICD in preventing SCD?

Dr. Olshansky: There has been a significant movement to ICD use for primary prevention of SCD. At 1 time, before receiving an ICD, patients had to experience 2 separate out-of-hospital cardiac arrests, so few patients used to qualify for an ICD. We no longer require a prior event, only that a patient is “likely to have cardiac arrest” ( Appendix ). Although there is some controversy about the criteria, most ICD implantations are for primary prevention, not secondary prevention.

Dr. Fonarow: Much of the growth of ICD utilization is due to the recognition that most antiarrhythmic drugs are ineffective for both primary and secondary prevention and are sometimes proarrhythmic, thereby increasing the risk for SCD. Two decades ago, flecainide and encainide were 2 of the top 10 cardiac medications prescribed, but they subsequently were found to increase all-cause mortality and are proarrhythmic. Other antiarrhythmic drugs, such as amiodarone, also fail to protect against SCD.

Dr. Friedewald: What is the relation between left ventricular (LV) dysfunction and SCD?

Dr. Fonarow: Patients with significant LV dysfunction—even in the absence of a prior cardiac event, ventricular ectopic beats on ambulatory monitoring, or inducible arrhythmia on electrophysiologic study—are at increased risk for SCD. Because up to 1/2 of deaths in patients with LV dysfunction are sudden, prophylactic ICD placement in this patient population is often indicated. Prospective randomized clinical trials in patients receiving optimal heart failure (HF) treatment with subsequent placement of the ICD demonstrated that they aborted SCD when compared to drug treatment alone, in patients with both ischemic and nonischemic forms of cardiomyopathy.

Dr. Friedewald: Do drugs that are not directly antiarrhythmic, but proven beneficial in treating patients with HF (i.e., β blockers and renin-angiotensin aldosterone inhibitors) reduce the risk of SCD in patients with HF?

Dr. Fonarow: Beta blockers reduce death from progressive HF as well as SCD in patients with LV dysfunction. Patients on β blockers, however, have a greater relative reduction in death from progressive HF, resulting in increased incidence of SCD in this population. The predominant effect of angiotensin-converting enzyme inhibitors is on death from progressive HF with possibly a slight reduction in the frequency of SCD. Aldosterone antagonists also decrease the risk of death from progressive HF, with possibly a slight reduction in the frequency of SCD. Thus, patients on optimal medical therapy for LV dysfunction and HF have enough residual risk for SCD that usually justifies primary ICD placement.

Dr. Yancy: Is there a role for antiarrhythmic drugs in patients with an ICD?

Dr. Olshansky: There may be a role for the use of antiarrhythmic drugs in addition to ICD therapy in patients who receive multiple ICD shocks for ventricular and atrial tachyarrhythmias. As primary therapy to reduce total mortality or arrhythmic death, however, antiarrhythmic drugs have no role. The important point is that ICD therapy reduces the incidence of both SCD and overall mortality.

Dr. Fonarow: It is important to separate absolute risk and proportional risk. The proportion of SCD relative to death from progressive left ventricular dysfunction is higher in patients with less severe HF symptoms—New York Heart Association class I or II—compared to patients in class III or IV HF, in which a greater proportion of deaths are due to progressive HF. Thus, although SCD occurs in patients in class III and IV HF, the absolute risk for deaths both from progressive HF death as well as SCD rises with increasing severity of HF. There is little benefit in preventing SCD in a patient who shortly thereafter dies from progressive HF. Thus, identifying patients who derive the greatest absolute benefit from the therapy and in whom the benefit outweighs the potential ICD risks is essential. In patients with class I to III HF treated with an ICD, the benefit outweighs the risk and prolongs survival. In class IV patients, however, because of the ICD impairment on quality of life and functional status, HF not amenable to optimal medical therapy precludes ICD therapy. Class II and III HF patients frequently die suddenly. Many of them also die from progressive HF, so they need protection from both major modes of death.

Dr. Yancy: Thus, patients with class IV HF may not be helped by ICD implantment.

Dr. Fonarow: That is true, except in class IV HF patients, who improve to a better functional class with other forms of treatment. Thus, class IV patients who are not candidates for cardiac resynchronization therapy, cardiac transplantation, or ventricular assist devices, and who remain persistently in class IV are not candidates for ICD under current guidelines because there is insufficient evidence that they benefit. Ambulatory class IV HF patients who receive cardiac resynchronization therapy combined with ICD, however, may have improved survival compared to patients on optimal medical treatment alone.

Dr. Yancy: Is SCD risk related to functional capacity in patients with HF?

Dr. Olshansky: Patients in functional class I and II HF are less likely to die, and when they die it is more often due to an arrhythmia. They are the patients that derive the greatest potential benefit from an ICD. Functional class III patients also have a high risk of arrhythmic death, but they also have greater risk of mortality from progressive HF than functional class II patients. Thus, the functional class III patient can benefit from an ICD. Functional class IV patients may not benefit from ICD therapy.

Dr. Roberts: Are you saying that the greater the LV dilatation, the greater the chance that death will be caused by pump failure, and the less the LV dilatation, the greater the chance that death will be due to an arrhythmia?

Dr. Olshansky: It is probably true that the larger the LV cavity, the greater chance of death from LV failure. Many LV parameters have been studied, however, and only 2 are clinically useful: (1) New York Heart Association functional class and (2) LV ejection fraction. Although they are not perfect, they are the best we have now.

Dr. Roberts: The LV ejection fraction is proportional to LV cavity size?

Dr. Olshansky: The possibility that LV end-diastolic or LV end-systolic volume is an independent predictor has not been studied. Thus, we use LV ejection fraction.

Dr. Roberts: The same is true for angina pectoris. With increasing LV cavity dilatation, there is less frequency of angina, and patients with grade 4 angina pectoris generally have normal LV cavity size.

Dr. Olshansky: One of the most challenging issues is risk assessment. Although our discussion is focused on primary prevention in patients with HF, there are many different patient types at increased risk for SCD whose LV function is well preserved. Patients with LV diastolic dysfunction alone, which is difficult to define, also are at increased risk of SCD. There also are patients at increased risk of SCD with certain genetic abnormalities, such as the Brugada syndrome, the long–QT interval syndrome, and hypertrophic cardiomyopathy, who do not have HF and have normal LV ejection fraction. For example, consider a 17-year-old girl with syncope and a QT interval of 560 ms on her electrocardiogram. Compare that patient to an 85-year-old man with an LV ejection fraction of 10% and functional class II HF on optimal medical therapy, who has a much greater risk of SCD, and a much greater chance of an ICD stimulus than the 17-year-old girl. Thus, clinical characteristics other than LV ejection fraction and functional class must be considered. The younger individual might use the defibrillator less, but her dying from cardiac disease almost surely would be from a cardiac arrhythmia. In the older individual, however, progressive HF and co-morbidities associated with age (renal dysfunction, atrial arrhythmias, and diabetes mellitus) are additional independent risks for mortality. Another group to consider for ICD therapy is comprised of patients with ischemic cardiomyopathy and nonsustained ventricular tachycardia (VT) who have relatively well-preserved LV ejection fraction and are in New York Heart Association functional class I. They also have sufficient risk of VT and ventricular fibrillation that may warrant ICD placement.

Dr. Roberts: Let us assume that a 60-year-old man develops substernal chest pain, goes to the hospital emergency department, and 3 hours after the onset of chest pain has cardiac arrest. Is that a form of SCD?

Dr. Olshansky: By some definitions, yes.

Dr. Roberts: By your definition?

Dr. Olshansky: Probably not.

Dr. Roberts: The World Health Organization uses death within 24 hours after a change in health status in their criteria for SCD, which is ridiculous! If a 24-hour definition from sudden change of previous health to an event is used, a lot of patients with acute myocardial infarction are included, and I believe they should not be included in the category of SCD.

Dr. Fonarow: The definition of SCD is important. There are, however, many definitions of SCD, including a stringent 15- or 30-minute definition or when it is completely unexpected and not explained by something else such as acute myocardial infarction. At one time, it was thought that many episodes of SCD in HF patients were not caused by tachyarrhythmias, rather by other mechanisms such as bradyarrhythmias, which would not be prevented by an ICD. We now know that a substantial proportion of out-of-hospital SCD events are caused by tachyarrhythmias and can be effectively detected and aborted with the ICD. The number of deaths that are bradyarrhythmic or due to other mechanisms such as myocardial infarction or are hyperkalemia mediated and cannot be aborted by the ICD constitute only a small proportion of SCD in patients with significant LV dysfunction after myocardial infarction or ambulatory HF.

Dr. Roberts: I use a 6-hour definition for SCD because within 6 hours after onset of chest pain, there is no histological evidence of acute myocardial infarction. Thus, patients with occluding thrombus are not included.

Dr. Olshansky: That is reasonable, but there is a lot we do not understand about SCD. Many cases of SCD, for example, are due to asystole rather than a ventricular arrhythmia.

Dr. Friedewald: According to current guidelines, who should receive an ICD?

Dr. Fonarow: The newest guidelines from the American College of Cardiology, American Heart Association, and Heart Rhythm Society are based on randomized clinical trials That establish ICD efficacy. For primary prevention, placement of an ICD is indicated for (1) patients with LV ejection fraction <35% who are at least 40 days after onset of the infarction with New York Heart Association class II or III HF; (2) patients with nonischemic dilated cardiomyopathy and LV ejection fraction <35% who are functional class II or III, do not have contraindications for an ICD, and have a reasonable expectation for good functional status for at least 1 year; and (3) patients at least 40 days post myocardial infarction who do not have class II or III HF but have class I failure with LV ejection fraction <30%. These categories comprise a large number of eligible patients who do not have any prior arrhythmias but are candidates for ICD by virtue of their clinical state, symptom class, and degree of LV dysfunction determined by LV ejection fraction.

Dr. Friedewald: What is the basis for waiting 40 days after an acute myocardial infarction?

Dr. Fonarow: Placement of an ICD soon after acute myocardial infarction has not shown a net benefit because some post–myocardial infarction patients have substantial improvement in LV function with reperfusion therapy and optimal medical treatment.

Dr. Yancy: The guidelines strongly advise that patients be on “reasonable” medical therapy. What is “reasonable,” and for how long should medical treatment be employed before ICD placement is considered?

Dr. Fonarow: Many patients with nonischemic cardiomyopathy have spontaneous improvement in LV function, even when untreated. Thus, they need a chance for recovery before receiving an ICD. Prior guidelines, which have been controversial, left this time frame up to the clinician. In most patients we can start β blockers and angiotensin-converting enzyme inhibitors at the same time in patients with HF and up-titrate them within 2 to 3 months to establish optimal medical therapy and then reassess LV function.

Dr. Yancy: It would seem difficult to withhold an ICD from a patient with significant LV dysfunction at risk for SCD for such a relatively long period of time.

Dr. Olshansky: Yes, especially in the common scenario of patients who are not receiving optimal medical therapy for nonischemic and ischemic cardiomyopathy, as they are at risk for SCD. Other patients of special concern are those with a recent myocardial infarction who have poor LV function, are being discharged from the hospital, and face a period of time before they are seen again. That time period encompasses an increased risk of SCD. Because patients with poor LV ejection fractions or impaired LV function have a high risk of nonarrhythmic death early, it is not clear that the ICD offsets that risk. The concern whether we are doing enough for those patients, however, remains. Some clinicians use “bridging” approaches, such as life vests and the automatic external defibrillator, but the efficacy data for such devices are poor.

Dr. Roberts: What percent of patients with HF die in the hospital?

Dr. Yancy: With acute cardiac decompensation, the average mortality is about 4%, but the range is 2% to 20%.

Dr. Roberts: When a patient with severe HF dies suddenly, do you attribute the death to sudden ventricular fibrillation or asystole, rather than to pump failure?

Dr. Yancy: This is a dilemma of clinical trials. When we try to adjudicate such deaths, we use arbitrary definitions. How do you set the time clock, and what does that mean? SCD is an unexpected or unanticipated event at some point after a patient is deemed “stable and comfortable.” The definition of “sudden” is a problem for many clinical trials.

Dr. Roberts: In-hospital death should be separated from out-of-hospital death.

Dr. Olshansky: I agree. There are some in-hospital sudden deaths that occur while patients are on the ICD, and these are reported as SCD. The mechanism can be either a ventricular arrhythmia or pulseless electrical activity.

Dr. Roberts: But patients receiving ICD therapy also die of HF.

Dr. Friedewald: Is patient proximity to medical care considered among the indications for ICD implantation?

Dr. Fonarow: For individuals having out-of-hospital SCD, even those who next door to the hospital, the chance of survival with intact neurological function is incredibly low, about 7%. Thus, geography is not a factor for ICD placement. Every second without adequate defibrillation makes survival after cardiac arrest less likely.

Dr. Friedewald: Does a low likelihood of patient adherence to cardiac medications affect ICD usage?

Dr. Fonarow: Patient adherence to HF medications is not a factor in the decision whether to implant an ICD. Patients with ICDs need to take medications. The device is not a replacement for medications. Patients with ICDs also require optimal medical treatment. The device does nothing to prevent progression of underlying LV failure. It is critically important to continue optimal medical treatment along with the ICD.

Dr. Yancy: What is the experience with the ICD in clinical settings in the context of guideline indications?

Dr. Fonarow: Among all patients hospitalized for HF in the American Heart Association Get With the Guidelines–Heart Failure program, only about 25% of eligible patients receive an ICD. Some eligible patients, however, refuse the ICD, and some do not meet additional criteria such as HF time of onset and the presence of co-morbid conditions. When these patients are excluded, about 33% of eligible patients are treated with an ICD. In the outpatient setting utilizing a registry like Improve the Use of Evidence-Based Heart Failure Therapies in the Outpatient Setting (IMPROVE-HF), the utilization rate is higher. About 50% of HF patients who are candidates under the guidelines receive ICDs. This means, however, that 50% of HF eligible outpatients in cardiology practices do not receive ICDs. In primary care settings the rate of ICD placement is even lower. Thus, despite excellent clinical trial evidence of their efficacy, a substantial proportion of patients who are eligible for ICD treatment do not receive it.

Dr Friedewald: Why is ICD therapy so underutilized?

Dr. Fonarow: It is very difficult to understand why evidence-based therapies, using either medications or devices, are not better adhered to, especially in view of all the information disseminated about guidelines. One factor with many other analogous therapies is a substantial lag from the time the therapy becomes evidence-based and recommended in the guidelines to when it is widely adopted. ICD treatment is relatively new, so the customary time lag is a factor in its underutilization. Another factor is that this treatment requires much more than a simple written prescription. ICD placement involves referral to an electrophysiologist, an invasive procedure, and close follow-up. Thus, some patients, even when fully informed about the benefits of ICD, decline implantation.

Dr. Olshansky: I am surprised that the ICD utilization is as high as 50% in outpatients. It has been my experience—not supported by any published data—that many physicians either do not know the data supporting ICD use, do not believe the data, or do not want to believe the data, so they simply do not even think about ICD therapy. There also have been negative stories published in the public media. Here is a quote from a major newspaper, which is representative of some of the public’s perception: “The number of patients receiving ICDs has actually declined as more doctors and patients decide the risks and uncertainties the device has posed may outweigh the potential benefits. Industry estimates and medical studies show that ICDs have saved the lives of only 10% of the 600,000 people who will receive them at most. Nine of 10 people who receive ICDs receive no medical benefit.” This is a misunderstanding of the science. When the number of persons needed to treat to get a benefit of saving 1 life is only 10 people, that is a tremendously effective therapy. We do not expect that every patient who receives an ICD will have his or her life saved by the ICD. We only expect risk reduction.

Dr. Yancy: We have excellent data demonstrating utility of the ICD in the appropriate patient with reduction in total mortality and sudden death. Some patients who receive an ICD never have a firing and when they do, it is an inappropriate shock. Others are concerned about costs and related risks. What do you think is required: more data? More time? Different perspectives? How do we optimize use of the ICD?

Dr. Olshansky: The issue comes down to the risk/benefit ratio and what is expected in The extension of reasonably functional life, which is difficult to define. If the life of an 85-year-old person is extended by a few months, is that of value to society or only to the individual? Is it worth the cost?

Dr. Yancy: Is this an ethical argument or a scientific argument?

Dr. Roberts: It is both. Are we going to have rationing of medical care? We are talking about expensive devices in a country that is broke.

Dr. Friedewald: What is the average increase in longevity in the group with the ICD?

Dr. Olshansky: An exact number has not been calculated, at least in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). In that trial, which is probably our best database of patients who have functional class II and III HF on the best medical therapy, there is a 23% relative risk reduction with a mean follow-up of about 45 months.

Dr. Roberts: What is the absolute risk reduction?

Dr. Fonarow: The absolute risk reduction over the 4 years of the study is 7%, so 70 lives would have been lost for each 1,000 patients not receiving an ICD. The mean age was 65 years, and they were primarily functional class II to III.

Dr. Roberts: The study patients had an LV ejection fraction of about 35%. What do we know about patients who are 40 days post myocardial infarction with greater LV ejection fractions?

Dr. Fonarow: An interesting paradox is that patients with better-preserved LV ejection fractions derive less benefit. It is the group of patients with LV ejection fraction <35% and especially <30% that derive much greater benefit. Thus, a cutoff of the LV ejection fraction of about 35% is reasonable, because among patients with an LV ejection fraction >35%, the number needed to treat to show a benefit is substantially higher.

Dr. Roberts: What is the range of error for the measurement of LV ejection fraction?

Dr. Fonarow: For most studies, the range is ±5%.

Dr. Yancy: Do you believe there is a greater physician bias against ICD placement than patient bias?

Dr. Olshansky: There is a significant physician bias, but I cannot quantitate it. Maybe we overemphasize the potential benefits because some trials do not show as much benefit as others. There are other post hoc analytic data about specific patient populations suggesting that certain types of patients do not achieve the same benefit as others. Patients with atrial fibrillation, patients with functional class III HF, and patients with renal dysfunction may derive less benefit. Older patients also may not have as much improvement of functional quality of life with the ICD as younger persons.

Dr. Fonarow: Such data can be misleading because trials are powered to look at the overall population. We can be misguided when we retrospectively study underpowered subgroups that appear to have less benefit with the ICD.

Dr. Yancy: There are data showing no statistical difference in outcomes with ICD therapy as a function of gender or race. There are, however, gender and racial differences among patients who receive ICD therapy, given the same indications. How does this apply to the American Heart Association’s Get With the Guidelines–Heart Failure?

Dr. Fonarow: Get With the Guidelines–Heart Failure is a hospital-based registry and performance improvement program from the American Heart Association. There are currently 424 US hospitals from all regions of the USA participating. The registry is comprised of >200,000 patients and includes data on demographics, treatment, LV function, previous device placement, hospitalization, and primary discharge diagnosis of HF or HF as the predominant reason for hospitalization. A study by Hernandez and colleagues looked at the use of the ICD in appropriate patients to see if there were disparities on the basis of patient age, gender, or race. One third of eligible patients received an ICD or planned ICD placement post discharge. There were substantial disparities by race and gender: 44% of eligible white men and 33% of eligible black men received an ICD; 30% of white women and 28% of eligible black women received an ICD. Adjustment for co-morbidities, insurance coverage, and other factors did not change these findings.

Dr. Yancy: The same disparities have been found in the use of cardiac resynchronization therapy.

Dr. Fonarow: Many published reports have focused on disparities of other cardiovascular procedures, surgery, and device implants. Among newer or more expensive therapies, a certain proportion of patients are less likely to be treated, and race and gender seem to be significant influences.

Dr. Olshansky: Do such disparities also occur with medical treatment?

Dr. Yancy: There is variance in the use of β blockers after acute myocardial infarction. For other evidence-based treatments, there is no demonstrable evidence of disparity in the medical care of inpatients. For activities such as counseling for smoking cessation or appropriate discharge orders, disparities emerge. In mammography for breast cancer screening, revascularization compared to amputation for peripheral vascular disease, hemodialysis compared to renal transplantation, and thrombolytic therapy compared to acute percutaneous coronary intervention, there is clear evidence of disparate health care.

Dr. Olshansky: Some disparities are patient related and others are due to physician ignorance or physician bias. I wonder if they depend on the physician-patient relationship. There are differences, for example, in the care of white women who see white female physicians, white male physicians, African American male physicians, and African American female physicians.

Dr. Yancy: Physicians who are culturally sensitive provide care in a more equitable manner.

Dr. Roberts: Is cigarette smoking a factor in ICD use?

Dr. Fonarow: Cigarette smoking is not a relative or absolute contraindication for ICD therapy.

Dr. Roberts: How do you advise patients who decline an ICD?

Dr. Fonarow: All of the other appropriate aspects of HF therapy are important, including medications, lifestyle modifications, and appropriate exercise in a cardiac rehabilitation program.

Dr. Olshansky: Some health care providers have a strong bias against persons who smoke cigarettes. Such an attitude toward cigarette smokers is a different type of bias from that of gender and race.

Dr. Yancy: Bias occurs in many different modalities and representations, which is why I believe we should consider an “across the board” performance improvement strategy for ICD therapy.

Dr. Olshansky: I am not an advocate of electronic medical records, but perhaps electronic medical records can be used to enforce proper medical management. For example, these guidelines could be built into electronic medical records in a way that a red flag would appear when a patient satisfied the indications for an ICD. If the physician did not prescribe it, or the patient refused it, the reasons for not using it would be recorded. This approach also might encourage device implantation in a manner that is blind to race and gender.

Dr. Fonarow: Whether systems such as electronic medical records can be successful in improving treatment with modalities as complex as placement of ICDs and cardiac resynchronization devices requires further study. With large gaps in treatment and the disparities that have been identified, we need to do something different from the present conventional “hit or miss” treatment approach. A more reliable, safe, effective, and unbiased delivery system consistently delivering appropriate therapies in all settings should be the goal.

Dr. Friedewald: Are there signs of disparity reductions for ICDs in the Get With the Guidelines–Heart Failure program?

Dr. Fonarow: Preliminary data suggest that there has been some improvement, but it is too early to be certain. In other areas, such as use of renin-angiotensin system inhibitors and β blockers, there is profound evidence that these types of programs improve the quality of care and treatment rates.

Dr. Friedewald: Perhaps guidelines themselves should place greater emphasis on race and gender issues.

Dr. Fonarow: I agree. The 2005 HF guidelines on indications for ICD implantation included a section on special populations indicating that the recommendations were applicable to both genders, all races and ethnicities, and to older patients. There is also tremendous variation in ICD use in the outpatient setting compared to the hospital setting. There are some hospitals that have very high rates of qualified patients being treated appropriately with an ICD, and others where the use is nearly zero. Sharing best practice information can decrease these variations, indicating that it is possible to achieve high treatment rates of appropriate guideline-recommended therapies.

Dr. Roberts: It seems to be much easier to set up standards and diagnostic and therapeutic criteria in institutions compared to the private practice setting.

Dr. Fonarow: I agree. In many hospital settings, where there are standardized practice protocols and multidisciplinary teams, quality improvement initiatives are more likely to succeed. This is true regardless of the hospital type: teaching or nonteaching, rural or urban, large or small. The outpatient setting, however, is a far greater challenge, but there have been successes in this area as well.

Dr. Friedewald: What is the role of electrophysiologic testing in assessing people for possible ICD implantation?

Dr. Olshansky: The electrophysiology test has a potential role in patients who have nonsustained VT, are not post myocardial infarction, have had no recent acute intervention, are clinically relatively stable, and have a LV ejection fraction <40% with New York Heart Association functional class I HF. This subset may benefit from electrophysiology testing to assess the risk for primary prevention with the ICD. T-wave alternans has been mentioned as a possible noninvasive predictor, but it will never be helpful in determining who should receive an ICD. T-wave alternans will ultimately fall the way of other noninvasive tests. We are left with only a hope for a good noninvasive predictor, so we must rely mainly on New York Heart Association functional class and LV ejection fraction.

Dr. Friedewald: Does persistent atrial fibrillation affect the indications for ICD placement?

Dr. Yancy: The patient with atrial fibrillation is at greater risk for HF and SCD.

Dr. Olshansky: For ICD indications, atrial fibrillation is a “2-edged sword.” A post hoc analysis of atrial fibrillation patients or syncope patients in the SCD-HeFT trial found that those patients do not benefit from an ICD but that they are at higher risk of both total mortality and fatal arrhythmia. Because those findings are post hoc analyses, it is hard to use those predictors to determine who would benefit the most from ICD placement. We do not have good prospective data to determine the highest risk patients. Some of the highest risk patients are also the oldest patients and the most likely to have other co-morbidities so that they are going to die anyway and therefore may not benefit much by receiving an ICD. Our challenge is to find a middle ground. The patient with an LV ejection fraction that is not too abnormal is not going to benefit much from an ICD, but when the LV ejection fraction is too low the patient also is not going to benefit from an ICD. Thus, there is an “in-between” population—with a modestly poor LV ejection fraction and modestly reduced functional class—who seem to derive the most benefit from an ICD.

Dr. Roberts: How much does the ICD cost?

Dr. Yancy: The usual metric for HF is $50,000 per quality-adjusted life-year. For an ICD, the cost is about $37,500. Thus, by accepted definitions, it seems reasonably cost effective.

Dr. Olshansky: It is at least as cost effective as many of our other standard medical therapies.

Dr. Fonarow: I agree.

Dr. Roberts: The most common mode of death in patients with angina pectoris is cardiac arrest. Would you personally have an ICD inserted if you had chronic stable angina?

Dr. Yancy: No, I would want surgical revascularization.

Dr. Fonarow: There is no evidence that ICD placement offers substantial value in chronic angina pectoris, but we do have great evidence in favor of antiplatelet drugs, β blockers, renin-angiotensin system inhibitors, and aggressive statin therapy.

Dr. Roberts: If you had an acute myocardial infarction 50 days ago, an ejection fraction of 40%, and class I HF, would you like to receive an ICD if money were not a factor?

Dr. Fonarow: No, because I would believe that with appropriate medical therapy, my risk would be low enough.

Dr. Yancy: What if your LV ejection fraction was 35%?

Dr. Fonarow: Then sign me up for an ICD!

Dr. Roberts: But the ejection fraction margin of error, at best, is ±5%.

Dr. Fonarow: Yes, so there is “wiggle room” for LV ejection fraction criteria. If I am measured at 35%, there is a possibility that I will be at 30%, and that places me in the group that derives greatest benefit from ICD placement. There is a little built-in error ratio around guideline recommendations.

Dr. Friedewald: What is the future of ICD therapy?

Dr. Olshansky: The future of ICD therapy depends in part on what the health care system can afford. While the price of defibrillators might be driven down by improved technology, the ICD will remain expensive. I assume, however, that technology will reduce device size and risk. For example, leadless defibrillators are being developed. They are big, but it is possible for these devices to be put in without leads, so there would be no leads to break. There also is progress in extending battery life.

Dr. Roberts: What is the current average battery life?

Dr. Olshansky: About 5 to 6 years, but if a patient only needs 1 device and if the device could be put in without a lead, the implantation procedure would be much easier and perhaps less expensive. Another issue is to better determine which patient populations to target, because we want to treat patients who are at the highest risk and are going to get the most benefit from the device. We have to define what is meant by absolute risk that is required for the ICD and which patients truly benefit from implantation. We also need better markers. While there should not be any bias with regard to who gets an ICD, there may be genetic differences among populations who benefit. This area needs research because genetic testing may help identify patients who will benefit the most.

Dr. Friedewald: What more should we do about ethnic disparities in treatment?

Dr. Yancy: I favor efforts that improve across-the-board adherence to evidence-based medical and device therapies. My observations over the last decade has demonstrated that there are few substantive differences between groups of individuals, especially on the basis of race, and that most of the differences in outcomes are due to the extent to which people receive evidence-based medical or device therapies. Performance improvement strategies that are deployed in a race-blind, gender-blind, age-blind manner are best. One mistake we made several years ago when we launched evidence-based therapy on the basis of race was that we forced the medical community to emphasize race, which was polarizing. The uptake in therapy that should have occurred did not occur, and many people suffered unnecessarily. In an era in which we have limited resources the best way to utilize them is to make certain that every patient affected with disease has the best possible chance for the best possible outcome, the lowest utilization of hospital services, and the greatest improvement in survival. The right approach is not a focus targeted toward a single group, because that does not work. Rather, the right approach is to raise the bar for all individuals with disease, recognizing that some will have a greater gain than others. Thus, wide deployment of quality-driven performance improvement strategies makes the most sense and is doable.

Dr. Friedewald: Thank you.