Global EP Summit: Innovation in Pacing

Podcast Transcript

Announcer:

Welcome to Cleveland Clinic Cardiac Consult, brought to you by the Sydell and Arnold Miller Family Heart, Vascular and Thoracic Institute at Cleveland Clinic.

John Rickard, MD:

Hi, my name is Jack Rickard, and the title of my talk is Integrated Care for the Heart Failure Device Patient, the CRT CHF Clinic. So, in this talk I'm going to be talking about a novel multidisciplinary clinic that was started at the Cleveland Clinic approximately three years ago. So, in our CRT population we identified a major gap in care and that is oftentimes patients once they got CRT, weren't getting optimized care across the board. So, we decided to create a clinic where patients would be seen by a heart failure physician and electrophysiologist in the same room at the same time, approximately six months post implant. And on that visit, medications and the device would be optimized to basically standardize how patients were receiving care after their CRT device. And these are my disclosures.

John Rickard, MD:

So, one thing you'll notice when you look at the professional society guidelines is that none of them mention what to do with patients after they get CRT devices. All the guidelines do a very good job at telling us who we should implant a CRT device in, basically mirroring the results of large-scale clinical trials. However, because the guidelines are silent on what to do after implant, care has been fragmented really worldwide, such that some patients get an echocardiogram in six months, some patients never get an echocardiogram afterwards, some patients never see a heart failure doctor. These are some of the sickest patients in cardiology, yet we're not standardizing their care, we're not delivering the care that they need after their implant. I don't want to say they're forgotten about, but they're certainly not scrutinized over to the same degree they were prior to implant.

John Rickard, MD:

So why should we care about how patients do after CRT implant? Well, if I told you that you are a non-responder to CRT, and in this way, we'll define a non-responder as someone whose ejection fraction has either stayed the same or gotten worse, the average person may not get too excited about that. However, if I told you, you had renal cell cancer in the U.K., that would probably get you more concerned, yet the two populations have the same survival. And not only that, the higher we can get the ejection fraction, even if you benefited from CRT, there seems to be a dose response such that the better the ejection fraction, the better survival is. So, we should really be trying to pay attention to trying to get that ejection fraction as high as possible post-CRT as that seems to be correlating with long-term outcomes.

John Rickard, MD:

In 2020 we are starting to think about how patients do after CRT differently. There have been over 13,000 papers written on "CRT response" dichotomizing the phenotype of post CRT patients into responder versus non-responder. But now in 2020 we really believe that there are probably five different things that can happen to a CRT patient. Number one is a super responder, that's the female non-ischemic who has this dramatic improvement in her ejection fraction. Then there's the responder that could be an ischemic who has a big left bundle and ejection fraction goes up by 10 points, 10 percent. But now we think there are three other phenotypes. This idea of a non-progressor, someone who is progressively dilated out for years, you give them the CRT device and at six months their ejection fraction may not have improved significantly, but you seem to have blunted the process of remodeling. So those patients clearly benefit from CRT.

John Rickard, MD:

Then you've got the true non-responder. This is probably the rarest of the population, where the patient neither gets better nor worse. They continue the same downhill trajectory despite CRT. And finally, the negative responder, being recognized in a small percentage of patients CRT can actually induce harm. These typically are your non-left bundle branch block patients potentially coupled with a poor lead position that can lead to actual harm from CRT. One of the things that when we first started this clinic that was really surprising to our heart failure doctors was that the CRT can cause harm if not delivered to the right patient in the appropriate way.

John Rickard, MD:

So, when we see a patient in our clinic, we really try to put them into one of three buckets. You've got on one hand patients with pure LV electrical conduction delay. That's your female non-ischemic big wide left bundle branch block. Those patients are going to have an enormous response to CRT. On the other hand, you've got patients with a widened QRS that's just due to myocardial disease, potentially a large LV mass, and that is your big ischemic cardiomyopathy giant LV and could have an IVCD pattern of 140 milliseconds. Those patients are the least likely to respond. And then everything in the middle. So, when we see a patient in our clinic, we try to put what the substrate is into one of these three buckets because that can kind of temper your enthusiasm to see how likely or not, they are to benefit from the therapy.

John Rickard, MD:

So, what are the reasons for patients not doing quite as well with CRT as we would've expected? Well in 2010 the thought was that suboptimal AV timing was the biggest issue, meaning that your AV delays weren't optimized and that was thought to be responsible for the majority of patients not doing well with CRT. Then you've got arrhythmias. Anemia cited as a major reason. Poor lead position, suboptimal amounts of biventricular pacing, that kind goes along with arrhythmias. Suboptimal medical therapy, persistent mechanical desynchrony. That was back when mechanical desynchrony was still really emphasized. Underlying narrow QRS, clearly compliance issues and primary RV dysfunction, but that's how things looked in 2010. Since 2010, we've learned a lot about CRT and in our clinic, we've learned that this may not be representative of what the reasons behind poor response to CRT are in 2020.

John Rickard, MD:

In 2020 we really believe these five factors are the biggest reasons why some patients don't do well with CRT. So poor electrical substrate, clearly non-left bundle branch block pattern such as a right bundle branch block or an IVCD do much worse than either a paced pattern or a left bundle branch block. Probable LV lead position. What we figured out is that clearly, we want to get the lead as far away from the septum as possible. We want a lateral location, which could be anterolateral. We try to avoid the middle cardiac vein, which parallels the PDA in the posterior part of the heart as that's not septal, that's not a lateral location, excuse me. Similarly, we try to avoid the great cardiac vein, which is on the anterior surface of the heart paralleling the LAD. That's also a poor lead position. It's not very septal.

John Rickard, MD:

A low percentage of biventricular pacing is very important, advanced or end stage myocardial disease. Is there a point of no return? We believe that when your LV dilation is out to eight and a half centimeters, you're unlikely to benefit from CRT. And lastly, frailty. That's an emerging factor. It seems that certain patients who meet criteria for frailty clearly don't benefit from CRT for reasons that are not quite clear.

So, when we looked at what the percentages were for the various reasons behind non-response in our CRT clinic where we've seen over 300 patients, we found that poor electrical substrate was a major reason behind CRT non-response in your non-left bundle branch blocks, your narrower kind of IVCD patterns. Number two, however, was severe cardiomyopathy with extensive scar. There are patients whose LV is so dilated and scarred up that it's past the point of CRT. It's past the point of significant mitigation with CRT. In frailty, poor lead position, significant arrhythmia burden, we found that some patients with uncorrected valve or infiltrative diseases or clearly a poor medical regimen or LV lead malfunction, those are all lesser reasons. One thing we notice is that oftentimes patients had multiple reasons for non-response.

John Rickard, MD:

So, this issue of a lack of standardized care for the CRT patient is important. This is a paper published in JACC recently by my colleague Niraj Varma, where they looked at how patients were treated if they were deemed to be a CRT responder versus non-responder. And what they found was that responders and non-responders really weren't treated any differently, meaning that once even patients who were diagnosed as not doing well with CRT, they didn't receive really any more intensified care than a traditional CRT responder. And this clearly is a problem in our eyes.

John Rickard, MD:

So, what is a Cleveland Clinic approach to this problem? The first large scale CRT clinic was at the Cleveland Clinic in 2010. This was a clinic where patients would be referred to for lack of response and a multidisciplinary team would troubleshoot and try to optimize care. Two years later, the StARR Clinic was formed at MGH, with Jagmeet Singh, where that was a care pathway approach. Every single patient who got a CRT device was systematically seen in the clinic multiple times, actually in the first six-month post-implant in hopes of trying to optimize care and improve outcomes.

John Rickard, MD:

So, the referral based, and care pathway types of CRT clinics have certain pros and cons. In the referral-based clinic you can achieve them with limited resources and time constraints. The problem is you miss a lot of potential non-responders because they're never referred to you as well as you often get these patients well past the time where you could have done something for them. Now the care pathway approach is advantageous because it catches all non-responders. You also have the opportunity to take a responder and maybe even make them a super responder and you're clearly identifying patients earlier in the disease process before they've kind of dropped off a cliff. The main con of this approach, it can be resource and time intensive, but our clinic was designed not just to start an interesting little CRT clinic at Cleveland Clinic, but we really tried to develop an algorithm that can be used in multiple different care settings.

John Rickard, MD:

The goal of our clinic was really to establish a type of model of care that can be replicated throughout the country. So, does a care pathway actually improve outcomes? Well, when they did this in MGH it showed that standardizing care for all CRT patients postoperatively resulted in a significant improvement in event in heart failure free survival out to two years, which was fairly impressive. So, at the Cleveland Clinic, this is how we run our CRT clinic. So, patients get their device, and they actually start hearing about the clinic prior to device implant from the implanting physician. And about six months after is when the patients see us in clinic and so the patients all have an echocardiogram before they see us. Then they come to our clinic and a nurse checks them in and performs a six-minute hall walk test and a battery of neurocognitive tests as well as things like a get up and go time, a hand grip strength test.

We're basically looking for mild dementia, we're looking for indices of frailty. While that's going on, the heart failure physician and I read up on the patient. We look at the CS venogram from the case. We look at x-rays, we look at all the details of the patient's past history, their medications. Then we review the data from the nurse and then we all of us go into the room. The heart failure doctor starts off with a full interrogation of the patient and a physical exam. At the same time while I am doing a device check, which is a basic device check with a couple additions. We make sure to get the pacing thresholds and the diaphragm status on all the pacing vectors. We look for whether multipoint pacing is on or off. We like to see if fusion pacing is on or off. We calculate QLV. Then after all that, we step out of the room and all of us huddled, and we come up with an individualized plan.

John Rickard, MD:

If the patient's doing great, that's great. They go on their merry way. If the patient's not doing well, they get, like I said, an individualized plan on where we think the patient needs to go from here, whether that's device optimization, we sometimes try to narrow down the QRS by changing vectors. Sometimes we send them for an LV mechanics echo to see if the lead is in the left in the least activated spot in the heart. Oftentimes we try to maximize their medication regimen. We send them to a heart failure pharmacist, and if they're really sick, they can get PA pressure monitoring referrals, monitored stress testing or onboarding to heart transplant or LVAD evaluations.

John Rickard, MD:

So, when you break down the common therapies we do for these patients into the reasons behind CRT, lack of response and for poor electrical substrate, you may try a fusion pacing, you may turn off the LV lead. It's possible CRT is just not for this patient. We could try multipoint pacing, optimal lead, suboptimal lead position. You can change the pacing vector. You can take them back to the lab to try to find a better spot, low percentage bi-V pacing, manage A-fib maybe through ablation or medications, or PVC management. And in advanced heart failure, optimizing guideline directed medical therapy, sending to a heart failure clinic, CardioMEMS, PA pressure monitoring or initiating evaluation for LVAD.

John Rickard, MD:

So, what are the tips to establishing a CRT clinic? You really have to create a multidisciplinary team that works well together, that was successful for us at Cleveland Clinic. You have got to involve your colleagues. We're not trying to become the heart failure and electrophysiologist for the entire Cleveland Clinic. We have to convince patients you're not trying to steal patients. This is just a new way of how we're doing things and then we send the patients right back to their physicians. I'm not going to get into this for talk but explain the value proposition for the hospital administration. We believe this is cost-effective. It takes some complex scheduling, so you have to engage your schedulers early, and then you really want to tailor your clinic based on available resources and time constraints. This is not something you need to do every single week. You do it once a month. We do it twice a month at the Cleveland Clinic.

John Rickard, MD:

So, if you'd like to learn more about our clinic and how it was designed and how it could be replicated in your own practice, the design papers published in this reference encourage you to take a look at this if you're interested in starting one of these at your own home institution.

John Rickard, MD:

In summary, patients undergoing CRT represent a severely comorbid population with heterogeneous electrical substrates and multiple possible outcomes following device implant. And we would argue that current models of care are not suited to provide adequate follow-up care for this population. We strongly believe multidisciplinary care can improve outcomes in CRT patients. We are looking for partners around the country to join us in this movement in creating these clinics. We'd be happy to become sister sites with you if you decide to go this route. You can email me or any one of us at the Cleveland Clinic who can get you my contact information to discuss this further. We'd love to have partners. Thank you very much.

Announcer:

Thank you for listening. We hope you enjoyed the podcast. We welcome your comments and feedback. Please contact us at heart@ccf.org. Like what you heard? Subscribe wherever you get your podcasts or listen at clevelandclinic.org/cardiacconsultpodcast.