State of the Art Coronary Artery Bypass Graft Surgery

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.
Betsy Stovsky:
Good morning. I'm joined here today with Dr. Bakaeen, whose director of our state-of-the-art coronary artery bypass surgery center, and he's here today to talk to us about bypass surgery and some of the great things that we've done at Cleveland Clinic and leading the practice to talk about some of the research and outcomes and the types of techniques that we do at Cleveland Clinic. Welcome Dr. Bakaeen.
Dr. Bakaeen:
Thank you, Betsy. It's a great honor to be with you. Always a pleasure. Again, this is a Zoom interaction between you and me. So if it's not as vivid and if my face is not looking exactly in the right direction, forgive the technology and forgive me. I'm not flesh out with it yet.
Betsy Stovsky:
Yes. We're all in a new world right now.
Dr. Bakaeen:
Yes.
Betsy Stovsky:
So, you have been involved in a lot of research and even in guideline committees and talking about coronary artery bypass surgery over the past years. So, I'd like to dive into some of the research that you've done and some of the information that you've been providing in your publications, et cetera. Can you talk a little bit about the different types of coronary artery bypass surgery conduits that you've written about?
Dr. Bakaeen:
Yeah, that's a great question. It's really the fourth year of the program of the clinic. When CABG was introduced to the surgical community back in the late '60s and '70s, Dr. Favaloro who was here, actually use the internal thoracic arteries in both of them actually in what's called the Van Berg procedure. He didn't do the anastomosis. Those were the early years before the actual CABG operation, where they actually sewed the internal thoracic artery to the coronary vessels.
So it also evolved over the years and they realize that the Clinic in the eighties that this internal thoracic artery stays open anecdotally from the heart caths that they did in collaboration with Dr. Sones, introduce the coronary angiography to the world, and they published the sentinel study. The seminal study, I should say, in 1986 in the New England Journal of Medicine, demonstrating that patients who geth their internal thoracic arteries and radial arteries if they need to bypass more than one blockage. So there's the ITA use to the LAD, which is the absolute minimum. And there is using more thant an internal thoracic artery ITA to the LAD have better patency of the ITA to the LAD compared to the vein.
And that was associated with a strong survival differential in favor of using the ITA. And then in the nineties, Dr. Lytle demonstrated that using two ITA's is better than one and so on and so forth. So, at the Clinic, the preference has been for years, do you use more arteries specifically more bilateral internal thoracic arteries than veins, and also to use the radial artery when possible, and some patients get the total arterial revascularization, meaning they get bo one ITA and then there's using two ITA's plus a radial artery, whether you combine them with veins or not depends on the number of vessels involved, the severity of the disease and the condition of the patient, the default strategy for any patient that comes and sees us in clinic is using multiaxial grafting for multiple blockages.
Betsy Stovsky:
So I know there was always these concerns about using both thoracic arteries ITA's and what did your research find as far as the patient outcomes with that?
Dr. Bakaeen:
Well, yeah, that's an excellent point. There is concern and anxiety amongst surgeons and certainly patients that, "Hey, if you use both arteries, they supply the blood to the sternum and then if you devascularize the sternum, then you increase the risk of infections and mechanical complications such as sternal malunion and the dreaded complication of a deep infection, which is Mediastinitis."
And indeed the art study demonstrated that you double to triple those complications in patients who receive a bilateral ITA's compared to one, but that same randomized study, which is the largest to date demonstrated that if you use meticulous technique and you skeletonize, those ITA's, then you actually take that risk and mitigate it and nullify it. And that's our experience at the clinic. We haven't had a sternal wound infection for a long, long time. It's not zero, but it's as close to zero as possible, primarily because of two things, one the technique and second patient selection. So if you get a morbidly obese patient with really poorly controlled diabetes, who's a smoker. You may want to think twice about using bilateral internal thoracic arteries. Having said that in that same patient, you could use a radial artery instead, for example, if you want to use a multi-tier strategy. So I think you got to select your patients and you got to select your surgeon when it comes to using bilateral ideas.
Betsy Stovsky:
And as far as surgery itself, you often talk about complete revascularization. And what are your specific goals during surgery?
Dr. Bakaeen:
The specific goal is to achieve an immediate, excellent outcome with low morbidity and mortality and a long-term outcome. We're not talking a long time over a year, we're talking about five, 10, 20, 30 years. So you got to go and do a perfect operation. And by that, I mean you bypass every single major vessel that has disease and you use the best possible conduits. And we prefer to use more arteries when possible. And sometimes we do use veins, but those veins have to be good quality veins. And so that when we study those patients in the future, if they ever get symptoms, which could be unrelated to heart disease, those bypasses will stay open for as long as possible. And we have studies from the clinic that demonstrate excellent outcomes over 20 years. Not many studies involving stents or indeed other revascularization procedures have that track record. And we're proud of this track record.
Betsy Stovsky:
There's been a lot of discussion over the years about off pump versus on pump bypass surgery. What are your thoughts about that?
Dr. Bakaeen:
Yeah, there's lots of debate which still goes on surprisingly enough. I was involved and still involved in the ROOBY study that demonstrated that really no real advantage to off pump CABG. In fact, you may have issues with graft patency using the off pump technique. This study was criticized because it was primarily conducted in a VA setting and the surgeons and investigators were criticized. But then other studies such as the Andrew Lima study, the Coronary study and the gold Cape study from Germany demonstrated essentially similar outcomes, meaning that there's no difference in major outcomes in MACE and survival up to five years between off pump and on pump CABG. And the criteria that they used in the coronary study was experienced surgeons. And in the German study, they used older and higher risk patients. So the arguments against ROOBY all fell through the cracks and the surgical community realizes right now that indeed in general, within a randomized controlled trial setting, there's really no difference in outcomes between on-pump versus off pump.
And in fact, retrospective studies and outcomes from centers with highly experienced surgeons, struggled to identify the difference and struggled to identify an advantage for off pump. Maybe well summarized by an international consortium of experts that concluded by saying that in the hands of off pump experts, you could achieve better outcomes in softer clinical end points such as less transfusions, less atrial fibrillation, but not in major outcomes, such as stroke, such as renal failure, such as peri-operative mortality. So in summary, I think they're equivalent, if you choose your surgeons and if you choose your patients and mash them together in an appropriate way.
Betsy Stovsky:
So you are always looking at quality and outcomes and quality improvement, and sometimes CABG is often thought of as just a common procedure. But what are the certain considerations that you have and the different types of things that you've put into place that help improve quality outcomes?
Dr. Bakaeen:
Yeah, I think you're right Betsy, I'm in charge of quality and it's always been a topic of tremendous interest to me. And I think it really starts by the preoperative phase. You got to select your patient, you got to select your surgeon and let's look at the patient. You got to look at the physiologic risk profile of the patient. You've got to look at the age. You got to look at the frailty. You got to look at the comorbidities and the life expectancy. And then you got to look at the anatomic aspect, which is how do the Coronaries is look like, what's the atherosclerotic burden, the size of the vessels, the quality of the aorta. And then you got to tailor your operation to achieve the best possible outcome.
So for example, if a patient with a calcified, ascending aorta with atherosclerosis within the lumen, you want to do an off pump, no touch technique, meaning that you're not going to put them on the heart-lung machine. You're not going to manipulate that aorta, and you're going to use a total or multi-arterial revascularization basing your blood supply for the bypass on the internal thoracic arteries that are left inside you or connected together in a composite. On the other hand, if the aorta is healthy and there's bad diffuse disease with small vessels, you want to do an on pump strategy that achieves complete revascularization. And again, you want to try and maximize the number of arteries when possible to ensure excellent longterm outcomes because again, yes, you want to have a, as perfect as possible short term outcomes, but you also want to make sure that that patient is enjoying quality of life and prolong survival for many years to come.
So we look at the peri-operative metrics and one way to look at that is the STS performance and we've been proud to be a three-star program for many years. Our mortality has been less than 1% for coronary artery bypass surgery for as long as I remember, despite the complexity of the cases, we get many referrals and turndowns from elsewhere, regionally, nationally, and internationally, and we get re operations first, second, third, re operations.
So, those excellent outcomes are despite the high degree of complexity of those patients, we have a great team and our results match that great team performance.
Betsy Stovsky:
So you were just mentioning to me earlier about high-risk bypass surgery. I think that's an important discussion, especially for healthcare providers who may be listening to talk about what do you do and patients that really are very sick, who are transferred here and how you work with the teams to provide the best outcomes for those patients.
Dr. Bakaeen:
Yeah, those are challenging patients and we have an open door policy. We like those challenging cases. We know how to take good care of them. It's really the strength of the clinic and has been from many, many years. So just to give you an example, last week, we had a patient transferred to us from another cardiac program because a very complex patient is a patient in his seventies who had a big heart attack and develop multi-system organ failure and they couldn't stent him. His liver function tests were highly elevated and abnormal. His kidney function was deteriorating rapidly. And in that context, taking this patient who needs a multi-vessel bypass to surgery in an emergency is a very high risk procedure because surgery is stressful as you know, and that patient would not have tolerated general anesthesia and cardiopulmonary bypass. It couldn't have been done off pump.
So what we did for that patient is that we stabilized that patient on a temporary mechanical support. We placed an auxiliary impeller, and by the way, he had a balloon pump, which wasn't sufficient. So we actually, balloon pump keeps you in bed because you need to lay flat is going through the femoral artery. I mean, you could move it to an auxiliary position, but the balloon pump only gives you about a liter, two liter, half of support. And that was not sufficient for a failing heart with an ejection fraction of 20%. So what we did was we took him to the operating room that same day and placed a right auxiliary impeller to give him over five liters of support. And within days his liver function began to turn towards his normal. His kidney functions began to improve. And what we did was, we cooled him off, we recovered the systems and then took him for a multi-vessel CABG.
And he actually did well and believe it or not, we actually took the impeller out at the conclusion of the procedure. And we didn't even have to put the balloon pump back. So this is just one example of a complex high physiologic risk.
We get lots of high anatomic risk, and we're really good at high anatomic risk because we get the patients with very diffused disease, small vessels, multiple blockages. We don't have to address those. We do multiple bypasses. We do endarterectomies. We achieve complete revascularization, the majority of the cases. And we also have a high percentage of reoperations. We do more reoperations at the Cleveland clinic than anywhere else in the world. And our results for redo CABG have been similar to primary isolated CABG since the late nineties, thanks to the accumulative experience of the excellent surgeons, my predecessors, we built on that experience. We built on the team experience and institutional experience to optimize outcomes in re operations. So in summary, our patients that undergo the operations have outcomes comparable to those when the go first time operations, and we have specialized program to take care of patients in shock, patients with high physiologic risk.
Betsy Stovsky:
Well, I think that we should end on that note. That was really a lot of information. I could keep talking all morning with you about bypass surgery.
Dr. Bakaeen:
Me too.
Betsy Stovsky:
But a lot to talk about, but thank you so much for being with us this morning and hope we could do this again, sometime.
Dr. Bakaeen:
My pleasure. And I'd like to thank everybody who's tuned in or about to tune in. Please reach out to us anytime. We'll be happy to discuss by phone, by zoom or in person. Thank you very much.
Betsy Stovsky:
Bye.
Dr. Bakaeen:
Bye.
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