Complex Controversies In Hemodynamic...

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Complex Controversies InHemodynamic Support CME / ABIM MOC

Supported by an independent educational grant from Maquet Getinge Group


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Complex Controversies In Hemodynamic Support

Target AudienceThis activity is intended for cardiologists, surgeons, and critical care specialists.

GoalThe goal of this activity is to provide an update on clinical trial data supporting the use of different hemodynamic support devices and on who would benefit from expert interpretation of the data, including benefits, limitations, and implications for clinical care.

Learning ObjectivesUpon completion of this activity, participants will demonstrate:

Increased knowledge regarding: • Clinical trial data supporting the use of different hemodynamic support devices

Greater competence related to: • Patient identification for different hemodynamic support strategies based on both ischemic and nonischemic etiologies

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ABIM Diplomates - maximum of 0.50 ABIM MOC points

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CME / ABIM MOC Released: 12/22/2016; Valid for credit through 12/22/2017


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Faculty Information and Disclosure Statements

Moderator Nico H.J. Pijls, MD, PhDProfessor of Cardiology, Catharina Hospital Eindhoven, Eindhoven, The Netherlands

Disclosure: Nico Pijls, MD, PhD, has disclosed the following relevant financial relationships:

Served as an advisor or consultant for: St. Jude Medical, Boston Scientific

Served as a speaker or a member of a speakers bureau for: St. Jude Medical

Received grants for clinical research from: St. Jude Medical, Macquet Getinge Group

Owns stock, stock options, or bonds from: General Electric, Philips, ASML Holding, Heartflow

Dr Pijls does not intend to discuss off-label uses of drugs, mechanical devices, biologics, or diagnostics approved by the FDA for use in the United States.

Dr Pijls does not intend to discuss investigational drugs, mechanical devices, biologics, or diagnostics not approved by the FDA for use in the United States.

PanelistsMohamed Abdel-Wahab, MD, PhDAssociate Professor of Internal Medicine and Cardiology, Head of the Cardiac Cath Lab, Bad Segeberg, Germany

Disclosure: Mohamed Abdel-Wahab, MD, PhD, has disclosed the following relevant financial relationships:Served as an advisor or consultant for: Boston Scientific

Dr Abdel-Wahab does not intend to discuss off-label uses of drugs, mechanical devices, biologics, or diagnostics approved by the FDA for use in the United States.

Dr Abdel-Wahab does not intend to discuss investigational drugs, mechanical devices, biologics, or diagnostics not approved by the FDA for use in the United States.


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Steven R. Bailey, MDChair, Division of Cardiology, Professor of Medicine and Radiology, University of Texas Health Sciences Center at San Antonio, San Antonio, Texas

Disclosure: Steven R. Bailey, MD, has disclosed the following relevant financial relationships:

Served as a speaker or a member of a speakers bureau for: Edwards LifeSciences

Owns stock, stock options, or bonds from: Bioz, Inc.

Dr Bailey does not intend to discuss off-label uses of drugs, mechanical devices, biologics, or diagnostics approved by the FDA for use in the United States.

Dr Bailey does not intend to discuss investigational drugs, mechanical devices, biologics, or diagnostics not approved by the FDA for use in the United States.

David A. Baran, MDDirector, Heart Failure and Transplant Research, Newark Beth Israel Medical Center, Newark, New Jersey

Disclosure: David A. Baran, MD, has disclosed the following relevant financial relationships:

Served as an advisor or consultant for: Maquet Getinge Group, TandemLife

Served as a speaker or a member of a speakers bureau for: Novartis Pharmaceuticals Corporation, Otsuka Pharmaceutical Co., Ltd.

Received grants for clinical research from: Astellas Pharma, Inc.

Dr Baran does not intend to discuss off-label uses of drugs, mechanical devices, biologics, or diagnostics approved by the FDA for use in the United States.

Dr Baran does not intend to discuss investigational drugs, mechanical devices, biologics, or diagnostics not approved by the FDA for use in the United States.

SD/Editor/Writer Information and Disclosure Statements

Caroline M. Padbury, B.PharmLead Scientific Director, Medscape, LLC

Disclosure: Caroline M. Padbury, B.Pharm, has disclosed no relevant financial relationships.

CME Reviewer Amy Bernard, MS, BSN, RN-BCLead Nurse Planner, Medscape, LLC

Disclosure: Amy Bernard, MS, BSN, RN-BC, has disclosed no relevant financial relationships.

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Complex Controversies in Hemodynamic Support

Nico H.J. Pijls, MD, PhD: Hello. I am Nico Pijls. I am a professor of cardiology at Catharina Hospital at the University of Technology

in Eindhoven in the Netherlands. Welcome to this program titled, “Complex Controversies in Hemodynamic Support.” Joining me today in Washington, DC, is David Baran, director of heart failure and transplant research at New Beth Israel Medical Center in Newark, New Jersey. Welcome, Dr Baran. Next to him is Dr Mohamed Abdel-Wahab, head of the Cardiac Catheterization Laboratory at Bad Segeberger Kliniken in Germany. And on the far end is Dr Steven Bailey, chair of the Division of Cardiology at the University of Texas Health Science Center in San Antonio. Welcome, everybody.


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In this program, we are going to talk about some of the clinical trial data supporting the use of the different hemodynamic support devices, the implications of using different mechanical support strategies in the setting of high-risk percutaneous coronary intervention (PCI), and how to choose patients who may benefit from hemodynamic support.

The first question is for Dr Baran; please summarize the different percutaneous mechanical circulatory devices with respect to their characteristics, benefits, and limitations.

Types of Percutaneous Mechanical Circulatory Support DevicesDavid A. Baran, MD: We are lucky in today’s catheterization laboratory to have a variety of tools. One of the tools that has been around the longest is the intra-aortic balloon pump (IABP), which now, like many devices, comes in 2 flavors: with the original 40-mL catheter and a larger 50-mL catheter. IABPs are versatile, being able to be placed in a variety of ways, from groin or alternate access points.

In addition, there is the Impella device (Abiomed, Danvers, MA), which originally was the Nimbus pump back in the 1970s; this is a very small pump that drains from the left ventricle (LV) to above the aortic valve. It comes in 2 sizes with flows between 2 and 5 L/min.

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Beyond that, there is a more complex system of left atrium-to-femoral artery bypass, the TandemHeart (CardiacAssist, Inc., Pittsburgh, PA), with a 21 Fr transseptal sheath and an arterial sheath of varying sizes, which definitely gives a higher degree of support with left atrial drainage. In addition, venoarterial extracorporeal membrane oxygenation (ECMO) can be placed with a large arterial and large venous cannula, depending on the need for full cardiopulmonary support.

Dr Pijls: Having heard about these devices, Dr Abdel-Wahab, can you tell us about the individualization of therapy? Can we make a choice of which device to use in which patient in what situation? Do you have a personal preference for a device? And, do you have certain recommendations about what device to use and in which patients?

Choosing a DeviceMohamed Abdel-Wahab, MD, FESC: These are probably the most difficult questions but also the most interesting ones because everybody working in this field wants to know at which level is each device needed and how one chooses between these different devices. Of course, if you are in a small hospital where only 1 device is available, then the choice is clear. Usually, in larger centers, you have access to all of these different devices. As mentioned, each of these devices has advantages but also disadvantages, which partly relate to the mechanism of action. The degree of support is definitely different for each, as is the degree of potentiation of coronary flow.

On the other hand, there are some safety and feasibility issues for the different devices that relate to the access site characteristics. If we compare an IABP device that requires a 7 Fr or 8 Fr catheter with an ECMO device that requires a catheter greater than 20 Fr, the difference in catheter size is one of the factors that is important to consider when you choose the right device for the right patient. All factors taken together should help to build an algorithm to find the right device for the right patient; the decision is definitely related to the patient’s condition but also to the advantages and disadvantages of the different devices.

Dr Pijls: Yes, we have to realize, of course, that the patients being considered are very sick and it is not always easy to categorize them into groups. Having heard that, Dr Baran, is it also possible to use some kind of stepwise approach? Do you sometimes use different devices? Do you start with 1 device? Tell us about your experience with that.


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Stepwise ApproachDr Baran: In our laboratory, if the patient is not in frank cardiac arrest -- they are sick but they are not to the point where you need complete cardiac support within a couple of minutes -- we tend to use an IABP first.

One helpful strategy is that you can assess the patient after the balloon pump is inserted and you have established coronary flow; you can then decide if additional support is needed. It is very easy to place a wire and exchange a balloon pump, at a low cost, to another device. That might be an upgrade to an Impella device or going to TandemHeart, or to ECMO because of its ease. Typically, we already have arterial access in 1 or 2 spots. It is very easy to do.

As well, if colleagues are performing the intervention, either my fellow or I can place the balloon pump in another arterial access site. It is very easy to do even if the fluoroscope is being occupied by another activity. The ease in which the change can be made is unique; you cannot do that with a lot of other techniques, where you really need the full attention of the staff. Dr Pijls: After having heard this problem, how do you to individualize the particular device for the particular patient? Is it useful to have a kind of shock team to discuss that?

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The Shock TeamDr Baran: In our institution, the shock team has proved to be very valuable, and it is continuing to evolve. The team may include a specialist nurse and an interventional cardiologist; often the referring cardiologist, who may not be as familiar with cardiogenic shock; and depending on the availability, a cardiothoracic surgeon or cardiac intensivist.

Those of us who do this for a living are used to a patient who is critically ill, but commonly the interventionist may not be as experienced with patients in shock and may be upset and flustered if the patient is clearly doing badly. There is a huge advantage of bringing in a squad, essentially a team who can focus just on the objective. What is wrong? Is there a need for a Swan-Ganz (Edwards Lifesciences)? They can look at the perfusion and rapidly help decide what is needed, because the biggest concern is being calm, collected, and organized.

The nurse has his or her particular role, which is very helpful, as well as the intensivist and the surgeon. Sometimes these are patients who need to go to the operating room, but most often, the team can decide what is an appropriate treatment and then work with colleagues. If I want ECMO, I will tell the intensivist, I need to work on getting this or this, please put in a large vein to go along with that arterial sheath. That calm sort of organized, collected fashion is one of the big benefits of the shock team.

Dr Pijls: That sounds very effective and perhaps should be standard in all the large hospitals using these devices.

Dr Baran: I believe it does save lives.


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SEMPER FI Study: Survival for Extensive MI With Persistent Ischemia After IABPDr Pijls: We have done a lot of research on the important role of autoregulation and the effectiveness of an IABP. The SEMPER FI study is under way.[1] During the past 20 or 30 years, we have seen the clinical enigma in which, in some patients, there is a dramatic improvement of the clinical condition with the use of IABP, especially after acute MI. In other patients, there are no effects. We have seen that many retrospective studies show good results, but it is very difficult to find a prospective study that shows a positive benefit from IABP.

Why are those differences present? How should we select patients? In our view, it is the autoregulation of the coronary circulation that plays an important role. What we should realize is that one of the major effects of the balloon pump is to increase diastolic perfusion pressure. In a normal, healthy person, this will not lead to an increase in coronary blood flow because the autoregulation will immediately counteract any positive effect of the balloon pump. However, when the autoregulation is exhausted, then coronary blood flow is proportional to diastolic perfusion pressure. In that situation, the balloon pump will increase coronary blood flow, will deliver more oxygen to the myocardium, and will indirectly improve the contractility.

We have tested that scenario extensively in animal studies, where we have seen that if we have a healthy state, a preshock state, and a shock state, there is an effect with use of the balloon pump. If we add ischemia into the picture, the effects are much more accelerated, and we have seen an increase in coronary blood flow up to 50% by using a balloon pump. That is the background for the SEMPER FI study.

In the SEMPER FI study, patients are investigated who sustained a large myocardial infarction (MI) and had ST-segment elevation of 15 mm or greater and who, after successful epicardial stenting had persistent, ongoing ischemia. The ischemia is defined as a less than 50% decrease in ST-segment elevation or persistent chest pain. These patients are randomized to receive a balloon pump or not receive the pump. We will show that survival is improved by use of the balloon pump.

There is a study conducted in patients with acute MI in other situations where the coronary artery regulation is exhausted. Are the patients in shock? They have a very low diastolic blood pressure -- less than 60 mm Hg. Patients with very tight critical stenosis and, at some points, patients after surgery with a stunned myocardium, where the autoregulation also was exhausted.

In the SEMPER FI study, patients with large MIs and insufficient ST-segment resolution are randomized to IABP or no IABP. If they are randomized to no IABP, they cannot cross over to IABP; if they need to cross over, they have to cross over to an ECMO device.

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SEMPER FI Patient: Left Coronary ArteryThis is a patient from the SEMPER FI study, a young man. You see the occlusion of the left anterior descending coronary artery.

Angiographic ResultsThe patient had successful reperfusion from stenting the artery.


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Electrocardiographic (ECG) ResultsThe ECG shows the moment when the wire was crossing the artery at 10:20 AM. At 10:26 AM, the stent was placed. There is still great ST-segment elevation. The patient received medications -- nitroglycerin, verapamil, adenosine, and abciximab -- and despite that, 8 minutes later there was still a huge ST-segment elevation.

Then we inserted the balloon pump at 10:45 AM. You see that 5 minutes later, at 10:50 AM, there is a dramatic decrease of ST-segment elevation, and 10 minutes later, it is almost normalized.

In these types of patients with ongoing ischemia, the higher perfusion pressure will increase coronary blood flow. The contractility is improved and the cardiac output has improved.

The study is now almost finished. We have included 80% of the patients, and the final results are expected in the course of the next year. We hope that this prospective randomized study will demonstrate the positive effect of IABP.

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When we go back in history to the recent studies, to the SHOCK II trial, for example, which almost invalidated the use of IABP, there is a lot of criticism.[2] At that point, I would like to turn to Dr Bailey to ask about the SHOCK II trial. Do you believe that this kind of trial is suitable to demonstrate anything? What are the weak points in such a study? Is an intention-to-treat analysis at all suitable to analyze this type of open study?

IABP SHOCK II TrialSteven R. Bailey, MD: We learned a lot from the SHOCK II trial.[2] The study group was large -- nearly 600 patients were followed. In this intention-to-treat trial, although the patients were randomized to receive PCI with or without IABP, the high crossover rate provides some significant confounding to the conclusions that were made, not just the fact that they were randomized up to a very late time point. The fact that they could be randomized up to 12 hours in and of itself raises questions.

Roughly 10% of the patients crossed over to the balloon pump. An additional 5% crossed over to other support devices. That crossover rate was 4% in the IABP group as well. We see crossing back and forth. Not surprisingly, that results in changes in the comparators that occurred in those patients.

We find that we “dilute” those patients who were high risk because now they have been removed from that control group. If you look at the intention to treat, of course, we have also changed that in an intention-to-treat analysis. The confounders that are brought up because of the SHOCK II trial do not allow meaningful conclusions, because of those features.

Dr Pijls: I fully agree with that. In fact, what you are doing is having an asymmetrical crossover. Why is that happening? What would be my personal feeling if a patient was in a no-device group and finally goes to the device group? Why does the physician decide to do that? The physician expects some positive effect of that. In fact, the sickest patients from the nondevice group are going to the device group. On the other hand, the patients who were randomized to receive a device and who were crossed over to no-device in the SHOCK II were the patients who died so quickly that there was no chance to even put in an IABP. There was, for my feeling, a double-negative bias for the IABP.

Dr Bailey: The other bias that occurs, of course, is these were very sick patients. Half were resuscitated in the field; 40% had cooling that occurred as part of protection. The ability to affect outcomes in those patients is similarly confounded by that. Ultimately, these confounders limit our ability to come to clinically meaningful conclusions.

Dr Pijls: Yes. By “late patients,” we mean patients who had sustained an MI at least 12 hours ago and no longer have viable myocardium, so improving oxygen supply and improving coronary blood flow with use of a balloon pump will not be helpful. It may helpful in the acute short term, but it is not durable.


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Dr Bailey: That is exactly right.

Dr Pijls: In general, we can say that an intention-to-treat analysis is unsuitable for an open study and for patients with a very bad outcome -- studies with a high event rate. It always will include negative bias, and there is an advantage of the device you are going to study.

Dr Bailey: A trial inherently does that. Absolutely. We need to be smarter about how we define these trials.

CRISP-AMI TrialDr Pijls: Dr Abdel-Wahab, if you look at a number of randomized trials conducted earlier, like the BCIS trial[3] and the CRISP-AMI trial,[4] the short-term effects were not positive in that there was no increased survival with the use of IABP, but in the long term, the effects became visible. Can you provide an explanation for this?

Dr Abdel-Wahab: It is a very important aspect because with use of the hemodynamic support device in the setting of cardiogenic shock or high-risk PCI, you expect some myocardial support and probably myocardial salvage, which will affect LV function. When you improve LV function or preserve ventricular myocardium, I do not think that you will see the effect on clinical outcome during the first 30 days. You need, probably, a much longer period to have this prognostic impact of myocardial salvage. This signal we have seen in trials like CRISP-AMI and BCIS -- this signal that is seen in the long term -- probably relates to this point of myocardial salvage that will not affect short-term survival.

You may wonder why this is not the case in the SHOCK II trial. One of the important aspects we have to discuss when we talk about SHOCK II is the timing of insertion of the hemodynamic support device, especially in patients with shock, because if you want to support the patient, you want to support him or her during the procedure, when a lot of factors are influencing the occurrence of ischemia related to reperfusion and reperfusion injury, and so on. If you delay the support until you finished all this, the myocardium will not derive benefit. You need it during the critical time of your reperfusion procedure. This probably explains the lack of benefit, even in the long term, in the SHOCK II trial. Timing is also very critical, and we have learned from a lot of mechanistic studies that unloading the ventricle during the intervention procedures is associated with better myocardial recovery.

Dr Pijls: Timing, of course, is very important. When the CRISP-AMI study was done, we hoped that insertion of the balloon pump before opening the artery would prove to be beneficial. Unfortunately, the results did not show that, but for the CRISP-AMI trial, we also had, of course, a number of very confounding factors. One of the issues was that in these patients, small MIs were included. Patients needed to have only a 2-mm ST-segment elevation in 2 occasional leads.

If you look at the results of the CRISP-AMI study and you look at all the patients, there was a slight benefit in advantage for the IABP group, especially when you looked at a combined endpoint at 6 months of readmission for heart failure and death.[4]

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If you filtered out the patients with large MIs, patients with a small ST-segment elevation of 15 mm, there was a greater difference between the 2 groups.[5]

If you then filtered out those patients who had insufficient reperfusion, there was a significant benefit in terms of survival for the patients receiving a balloon pump. Although that is, of course, retrospective analysis, a subsidy so to say, it is helping us to come to the “ideal hypothesis” of where a balloon pump should be used and where it should not be used.[5]

CRISP AMI Substudy: 6-Month MortalityDr Abdel-Wahab: This shows, again, the complexity of the patients who are involved in all of these studies. This is no single, homogeneous group. This is a heterogeneous group of patients, and it is extremely difficult to prove that one strategy vs another is beneficial in all patients. Of course, looking back and doing post hoc and subgroup analyses is, perhaps from a statistical point of view, inferior to looking at the whole population. On the other hand, this is why your study that is ongoing is trying to focus on the subgroup of patients whom we believe would derive the most benefit but in a randomized way. It is difficult to perform such a study, so I am sure we will learn a lot from studies like that. It is the way to go.


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Dr Pijls: In many studies of patients in intensive care units, if you look, for example, to the issue of administering corticosteroids in patients with shock, there are conflicting results. These studies are open and there is a very high crossover rate; you can never say, what is a real effect and what is not.

In the studies with IABP, there was another issue that is important with every support device. If a support device results in less damage of the LV and the ejection fraction is, let us say, 35% instead of 30%, you cannot expect that this will affect mortality in 6 months or even a year. It takes years before that effect becomes visible. I believe that is the true reason why, in a study like BCIS, there was a significant benefit after 5 years for the patients who received a device.[6]

Trials in Patients With ShockDr Baran: There is a huge selection bias in all of these trials, having been 1 of the sites for CRISP-AMI. All of these trials are challenging because you are asking investigators to randomize. Typically, the family member has to provide consent on very short notice. In a trial like SHOCK II or in CRISP-AMI, with the patients who definitely need a device, these will not be enrolled in a trial. Physicians do not have true equipoise. The patients who are enrolled could benefit from either strategy. Inherently, that population is less rich in those who are probably the sickest.

Dr Pijls: Yes. I agree with that. If you look at this kind of study, a study like SHOCK II, I believe that the investigators, Thiele and colleagues, also realized that the intention-to-treat analysis was not the best analysis. They went to a per-treatment analysis, but that also has severe shortcomings. Could you comment on that, Dr Bailey?

Dr Bailey: Just looking at that per-treatment analysis, you can imagine the impact. Now we are taking people who originally came from the low-risk group and contributing those to that high-risk group, which further disables us from showing differences between the groups -- you have taken that treatment group, the IABP group, and brought it closer.

Dr Pijls: Yes. What you are doing then is changing the baseline characteristics. You have 2 groups with completely different baseline characteristics. The outcome in both groups is the same, so you would even be prone to say the group with the device has done better because of worse baseline characteristics. There is reasoning to do so. It shows us just how difficult it is to interpret these data. The fact is that a number of patients experience a huge effect from the use of support devices, and it is our task to select those patients with wide criteria to see who would benefit from what.

Dr Baran, I have another question to you about the economics of hemodynamic support. That is, of course, an important issue. Hemodynamic support is expensive. Can you tell about that in terms of initial hospitalization and in terms of readmission?

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Device CostsDr Baran: Yes. It is interesting. If you look at all the devices, the least expensive device is a balloon pump. Then there are devices like the Impella, for which, in the United States, the catheter alone costs more than $25,000 to $30,000, depending on which device you use. TandemHeart is probably around the same cost.

Perhaps the costliest of the methods is ECMO. Although it is relatively inexpensive to insert the cannulas for venoarterial ECMO, in the United States usually a perfusionist will have to be at the bedside, which is a very costly endeavor. Having the perfusionist available around the clock or the device used to run the perfusion leads to high costs.

Compared with the costs of devices like the Impella or of ECMO, the cost of entry of a balloon pump is very low. And it is universal; it does not take away options. For example, if a patient receives one of the other support devices, like an Impella, and the device fails, then I am going switch to something else, like ECMO. I usually cannot remove the Impella device because it required a very large arteriotomy. I cannot wire it up. In terms of long-term readmissions and so forth, it is hard to know whether data will shake out in these patients. You have to customize (treatment) for the individual patient. Certainly, if a patient is beyond salvage and is in refractory cardiogenic shock, then it does not make sense to use a very expensive device. It may be better to go directly to ECMO or something else. Readmissions also are hard. There are not a lot of robust data to guide us because we are all colored by the fact of the high mortality; at least 40% or 50% of these patients will die soon. Readmission does apply here.

Dr Pijls: Yes. It is always the paradox in this type of medicine. The patients in whom you have to spend the most funds are doing worst. We cannot avoid that; it is part of the job. Dr Abdel-Wahab, how is the situation in Germany? How many IABPs are you using at your center, and when do you switch up to ECMO? If you have patients with acute MIs, what is your preference?


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Impact of SHOCK II Dr Abdel-Wahab: That is a very good question. The publication of the SHOCK II trial results has affected the use of IABP in Germany. I am sure it affected the use of IABP in general, but particularly in Germany because this was, essentially, a German trial.

There are 2 sides for this. One side is okay. If you believe you will need other devices to provide more hemodynamic support and the possibility for a stepwise approach, for example, this is good. We learn how to deal with newer or more complex support devices. The other side of this is dangerous. There are some centers that, because they believe IABP is no longer useful, they stopped using IABP without having something else -- medical treatment or ionotropic support – to replace it, which is dangerous.

Even if the guidelines say you can stabilize patients for a certain time with ionotropic support, as we discussed, timing is a very important factor, and patients who are not stabilized with pharmacological therapy require an intervention immediately. If you do not have options, this could be deleterious. This is the situation in Germany during the past 3 years. If response to the results goes in one direction -- just to expand your options -- this is perfect. If it goes in the other direction, this is very dangerous.

Some Cardiac Assist Trials

PROTECT II[7]

• No statistical difference in primary endpoint (30-day major adverse events) between groups: 35.1% for Impella 2.5 (n=226) vs 40.1% for IABP (n=226) (P =.227) in patients undergoing high-risk PCI

ISAR-SHOCK[8]

• Significant increase in cardiac index at 30 minutes from baseline in patients with the Impella LP 2.5 (n=12) compared with patients with IABP (n=13) (Impella: ΔCI = 0.49 ± 0.46 L/min/m2; IABP: ΔCI = 0.11 ± 0.31 L/min/m2; P =.02) in patients with cardiogenic shock

• No statistical difference between cardiac index at 30 minutes after device implantation for Impella (2.20 L/min/ m2) vs IABP (1.84 L/min/m2) (P =.18) (N=26) in patients with cardiogenic shock

• No difference in 30-day mortality outcomes

IMPRESS[9]

• No significant difference in mortality at 30 days for Impella (46%) vs IABP (50%) (N=48) in patients with cardiogenic shock

• At 6 months, the mortality rate was 50% in both groups • Meta-analysis of 3 studies with a total of 95 patients yielded results similar to results of the IMPRESS in Severe Shock study, with no difference in all-cause mortality at 30 days or 6 months

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Dr Pijls: I agree with you. In Holland, we have an expression – “Do not throw the child away with the bath water.” That is, here, the case. In fact, due to the SHOCK II trial, we did more experiments and learned to better understand when IABP is useful and when it is not. All of us are interventional cardiologists. We are all treating acute MIs at night by stenting them, and we all know many examples of patients who did very badly and suddenly improved after a balloon pump was introduced.

How is the situation in San Antonio? What are you using in your center and in what situation?

Dr Bailey: We follow a stepwise approach -- a balloon pump in the acute situation may be more expedient, more available, for those who need flow as opposed to reperfusion. Those patients get moved into a higher level of care with Impella or other devices. We are learning more about the appropriate use of a balloon pump and the appropriate patient for that treatment, about their clinical presentation. Are they in shock? Are they in extreme shock? How can we help with that? We are seeing a relative persistence of the use.

It is a little bit different than the National Cardiovascular Data Registry, which reports a decrease with these data, much as has happened in other countries. As we learn more, we are not giving this up. It has an important use.

Dr Pijls: The major issue is to distinguish, do I like to have a flow device or a pressure device. I believe that persistent ischemia is one of the important issues.

Expert PerspectivesWhat we can learn from this interesting discussion is that IABP may be particularly useful in patients with viable myocardium who are experiencing persistent ischemia despite an unobstructed coronary artery -- particularly patients with shock or who are in preshock and have ongoing ischemia and acute STEMI for whom epicardial stenting was successful but with no reflow. Sometimes, these are the patients, after cardiac surgery, who have good bypasses but a stunned myocardium. In such patients, IABP will increase diastolic aortic pressure, thereby improving blood flow to the myocardium and thus improving oxygen utilization by the myocytes and improving contractility and cardiac output, ultimately leading to salvage of myocardium with an improved long-term outcome.

Thank you all for being here for this interesting discussion. Drs Bailey, Abdel-Wahab, and Baran -- it was a pleasure to have this discussion. We hope that it will contribute to a better treatment of your difficult-to-treat patients who are in need of these kinds of devices. Thank you again.

This transcript has been edited for style and clarity.


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References1. ClinicalTrials.gov. Intra-aortic balloon pump in extensive myocardial infarction with persistent ischemia (SEMPER FI). https://clinicaltrials.gov/ct2/show/NCT02125526. Accessed November 12, 2016.2. Thiele H, Zeymer U, Neumann FJ, et al; IABP-SHOCK II Trial Investigators. Intraaortic balloon support for myocardial infarction with cardiogenic shock. N Engl J Med. 2012;367:1287-1296. 3. Perera D, Stables R, Thomas M, et al; BCIS-1 Investigators. Elective intra-aortic balloon counterpulsation during high-risk percutaneous coronary intervention: a randomized controlled trial. JAMA. 2010;304:867-874. 4. Patel MR, Smalling RW, Thiele H, et al. Intra-aortic balloon counterpulsation and infarct size in patients with acute anterior myocardial infarction without shock: the CRISP AMI randomized trial. JAMA. 2011;306:1329-1337. 5. van Nunen LX, van ‘t Veer M, Schampaert S, et al. Intra-aortic balloon counterpulsation reduces mortality in large anterior myocardial infarction complicated by persistent ischaemia: a CRISP-AMI substudy. EuroIntervention. 2015;11:286-292. 6. Perera D. BCIS-1 mortality data to 6 years. Presented at: American College of Cardiology 61st Annual Scientific Session; March 24-27, 2012; Chicago, IL.7. O’Neill WW, Kleiman NS, Moses J, et al. A prospective, randomized clinical trial of hemodynamic support with Impella 2.5 versus intra-aortic balloon pump in patients undergoing high-risk percutaneous coronary intervention: the PROTECT II study. Circulation. 2012;126:1717-27. 8. Seyfarth M, Sibbing D, Bauer I, et al. A randomized clinical trial to evaluate the safety and efficacy of a percutaneous left ventricular assist device versus intra-aortic balloon pumping for treatment of cardiogenic shock caused by myocardial infarction. J Am Coll Cardiol. 2008;52:1584-1588. 9. Ouweneel DM, Eriksen E, Seyfarth M, et al. Impella versus intra-aortic balloon pump for treatment of cardiogenic shock: a meta-analysis of randomized controlled trials. J Am Coll Cardiol. 2016. [Epub ahead of print]

Abbreviations

CABG = coronary artery bypass graft surgery

CI = confidence interval

ECG = electrocardiogram/electrocardiographic

ECMO = extracorporeal membrane oxygenation

Fr = French

IABP = intra-aortic balloon pump

ITT = intention to treat

LV = left ventricle/ventricular

LVAD = left ventricular assist device

MI = myocardial infarction

MOA = mechanism of action

MR = magnetic resonance

PCI = percutaneous coronary intervention

RCT = randomized controlled trial

STEMI = ST-segment elevation myocardial infarction

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