Mark Anderson, MD, Chief of the Division of Cardiac Surgery at Hackensack University Medical Center, talks about a new device that could save many more patients.
Which cardiac conditions is the Impella 5.5 effective for? Is it after heart attack, or after heart failure?
ANDERSON: The Impella 5.5 is appropriate for a broad range of patients. Its primary function is for acute cardiogenic shock, which is most commonly secondary to a heart attack or myocardial infarction. It’s also useful for other indications or causes of acute cardiac dysfunction, such as myocarditis or a viral infection of the heart, or for patients that have known cardiac dysfunction or known heart failure that sometimes become decompensated. So, there is a broad spectrum of patients that the Impella device can be useful for.
Can you tell us about the Impella device and what’s different about the 5.5 version?
ANDERSON: The Impella device is functionally the world’s smallest heart pump. There have been several iterations on the technology, but the five and the 5.5 really represents the most recent iteration. The value of the 5.5 pump is that it is the most powerful of the Impella devices in terms of its flow capabilities. It’s also been redesigned to facilitate implantation. So, for physicians that are implanting the device, the 5.5 is the easier to implant. The device is also designed to stay in place for a longer period, which gives us more flexibility with regard to supporting patients for a longer period of time. From the surgeon’s perspective, it has wrapped all the issues that we needed, meaning more durability, easier implantation, and higher flow. All the things that we had been hoping for from the surgical perspective is all wrapped into one with the 5.5.
How long can it stay in place? Is this a permanent solution or just a bridge, per say?
ANDERSON: Currently, it can stay in place as long as the physician feels that it needs to stay in place. There have been patients that have had the device for several months, which is different than the earlier iterations of the Impella device where it was really for acute short-term support, or just a couple of days. The 5.5 is really designed for prolonged implantation for months and even longer if necessary.
Can you explain briefly what it is that the device does for someone?
ANDERSON: The device is inserted through the axillary artery surgically through a small incision and passed into the heart, the left ventricle, which is the main pumping chamber of the heart. It effectively takes over the work that the left ventricle needs to do. Once we have it within the heart, the pump is initiated, and we secure it and close the incision. Another one of the very favorable characteristics of the 5.5 is that patients can get up, get out of bed, and walk around the hospital. However, patients can’t go home with this pump. There is a new iteration of the pump that’s coming that will be a discharge pump that patients can go home with. This allows us to rehabilitate them while we’re waiting for their heart to recover.
You mentioned it is easier to implant because of the size? Is it smaller?
ANDERSON: Yes. Even though this is the most powerful of the pumps, they were able to make it smaller in terms of the length of the motor. They also made the catheter that the pump is mounted on a bit more rigid. So functionally, the implant of these devices is easier than the previous Impella 5.0.
Does this allow patients time for their own organ to heal and become stronger? Or is it a bridge for a transplant?
ANDERSON: Our main focus is for patients to recover their own hearts. That is favorable for obvious reasons. In the vast majority of cases, in the acute setting, the heart will heal itself if it’s placed in a favorable environment. That favorable environment is to take the workload off the heart, let it rest and recover. The Impella device is what takes the workload off the heart, supports the patient’s circulation and lets the heart recover. The amount of time that takes varies. It depends on how big the heart attack was or how bad the viral infection in the muscle is. It can be a couple of days, a week or two, or it could be even months. But our focus is to try to get patients’ hearts to recover, take the device out and then they go on with their native heart. Now, that’s not possible in all circumstances. Some people start with a heart that’s already dysfunctional and then they have an acute injury on top of that. That heart is just not going to be a heart that’s going to be able to recover and support them. So, the Impella device can serve as a bridge. In general, we say it’s a bridge to recovery. It can be a bridge to another therapy, such as an implantable left ventricular assist device or a heart transplant.
Is there some technology that’s particular to this version, the 5.5, that allows clinicians and doctors to monitor what’s going on and can you tell me about that?
ANDERSON: Yes. This technology was not available on the previous iteration. It’s called the Smart Assist Technology. And basically, what it is, it allows us to assess the pressures within the heart and to assess the function of the native heart. The point being is that we can tailor the, you know, the amount of support that the Impella device gives to the individual patient. It also allows us to assess for recovery. And for example, if we turn the Impella pump down, we are able, with the Smart Assist Technology to see what the patient’s native heart is doing. If the native heart starts to generate pressure and cardiac output as we turn the Impella device down, we see, you know, obvious signs of recovery or vice versa, when we turn the Impella device down using Smart Assist, we don’t see the native heart starting to contribute, then we know that heart is not ready for the Impella device to be weaned off so we go back and support them longer. And we can go through, you know, that cycle, which we call, you know, trials of weaning. And then – but the Smart Assist Technology really allows us to do it in a very sophisticated manner, whereas previously, we were just kind of guessing. We would look at the patient’s blood pressure, maybe have an echocardiogram and kind of, you know, and kind of just guess at whether or not a heart was really ready to recover or had recovered. But with Smart Assist now, we really had some real time, you know, idea of what the heart is doing when we wean the Impella device. So it’s a major step forward in the field. It’s somewhat sophisticated but yes, it is built into the device itself. It has an optical sensor and it’s able to, you know, assess pressures and pressure differentials. And so it’s a very sophisticated algorithm that it has, but it’s highly accurate. And it’s, again, a very, very useful tool for us when we’re managing these patients and assessing them for weaning and recovery.
Is this lifesaving for patients?
ANDERSON: Oh, absolutely. Absolutely. We are fortunate we have a very strong heart failure group here, a very strong interventional cardiology group. So with respect to an acute cardiogenic shock program and heart recovery program, we have a very robust program here with algorithms of how we assess and treat patients with acute cardiogenic shock of all types. But we have been able to not only save lives with it, but save hearts, so to speak. It’s one thing to save a life which is obviously critically important. But if that patient then just subsequently goes on with heart failure, you know, that’s – you know, and requires an advanced therapy in the future, that is not ideal. So our goal is to get the patient to survive, to save a life but also to get native heart function to recover. So it’s really, you know, obviously the best of both worlds. Not to say that transplant doesn’t have a role in a select group of patients. But our aim is to minimize anybody that might need to go on for an advanced therapy like that.
And about how long has this been available and about how many have you and your partners worked with?
ANDERSON: We were actually the first institution to implant the 5.5, but we were working closely with some other centers, Cleveland Clinic, as well as Cedars-Sinai in Los Angeles. We’re the first centers in the country to have the device. Since then, we have done about 50 of these cases, as have the other groups. And the device has now been used in other institutions within the country. So probably the experience nationwide or worldwide, I would say, is probably upwards of 1,000 cases. So not a enormous number but still a good number of cases that have been done. There’s a couple of publications of which we’ve participated in as authors, as well as we’re part of a national trial with the Impella 5.5 device, along with the Cleveland Group and the Cedars-Sinai Group called the SURPASS Study, which will be evaluating the Impella 5.5 and the outcomes with its use in an ongoing manner.
Do you have anything, Doctor, that you’d be able to show us that shows the device implanted? Do you have any scans or anything that you might be able to pull up that we could see?
So, this is what the Impella device looks like. It actually has a longer catheter, but this has been divided for purposes of demonstration. So again, the pump is introduced from here in the axillary artery and then into the heart. So, it comes down into the aorta and goes through the aortic valve and into the left ventricle. Here you can see there’s aorta – this patient has had an aortic valve replacement, but this is how the pump sits within the heart. The inlet is here in the left ventricle and then the outlet is right above the aortic valve. And the motor sits on the catheter. The motor is here. So, the blood is taken in and within the left ventricle, it’s ejected here above the aortic valve and it sits just like this. And then we’re able to secure it in position and it doesn’t move. It stays in very well fixated and we can leave it there as long as we need to. So that is how this pump would be situated in the heart.
And how long is the procedure, Doctor?
ANDERSON: For us to implant this generally takes about 45 minutes. It is a surgical procedure. So, in general, the patients have to go to sleep and have anesthesia. But most of the time, these patients are quite ill and often already are, you know, have a breathing tube in place. And so, it’s, you know, it’s not a difficult procedure. We can do it in the cath lab or in the operating room. It’s a very small, limited incision. And the second half of that is the X plant of the device, really can be done with just local anesthesia at the bedside and right, exactly. We just kind of open it and out it comes and that’s that. Again so, how we implant the pump is through a small incision underneath your clavicle here. And we are introducing the catheter into the axillary artery or subclavian artery here, and it traverses and then comes into the ascending aorta, which is the big blood vessel that comes out of the heart. And then we’re able to direct it through the aortic valve and into the left ventricle. So we have the inlet of the pump in the left ventricular cavity and then the outlet of the pump is just above the aortic valve. This particular patient has had an aortic valve replacement. So the inlet is here. It unloads the ventricle is the term we use, which means taking the workload off the heart, allows the heart to decompress and decompress and then recover its function. And all the while, having 5.5 liters of flow to the rest of the body that is coming out of the outlet here. And you can see and this is why we say this is the world’s smallest heart pump, this little pump here has a kind of a propeller inside it driven by this motor, and it’s capable of flowing over five liters of flow from this little teeny pump here. So that’s why it is, in fact, the world’s smallest heart pump, very powerful and very effective.
Interview conducted by Ivanhoe Broadcast News.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
If you would like more information, please contact:
MARY MCGEEVER
MARY.MCGEEVER@HACKENSACKMERIDIAN.ORG
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