PANEL DISCUSSION OF ANOMALOUS CORONARY ARTERY OFF THE PULMONARY ARTERY Montefiore Einstein Heart Center New York City, NY February 7, 2007

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1 PANEL DISCUSSION OF ANOMALOUS CORONARY ARTERY OFF THE PULMONARY ARTERY Montefiore Einstein Heart Center New York City, NY February 7, :00:11 ANNOUNCER: Welcome to the Montefiore Einstein Heart Center in New York City. Tonight's live panel discussion involves a repair of an anomalous coronary artery off the pulmonary artery, or ALCAPA, in a 10-year-old girl. Dr. Robert Michler, chairman of the department of cardiothoracic surgery, will moderate while Dr. Sam Weinstein, the performing surgeon, will provide commentary on the procedure video. This congenital defect results in deoxygenated blood being fed into the heart. 00:00:42 SAMUEL WEINSTEIN, MD: Ninety percent of children with this defect will die if undiagnosed within the first year of life. For whatever reason, she was able to develop an extra amount of extra blood sources to her left heart through what we would call collateral vessels, and she survived to be 10 years of age. 00:01:00 ANNOUNCER: Dr. Weinstein performed a version of his procedure, called a Takeuchi repair, an interpulmonary artery tunnel, or baffle, to redirect oxygenated blood into the aorta. During the live panel discussion, make appointments, request more information, or your live questions to the panelists by clicking the MDirectAccess button at any time. Now let's go to the moderator of tonight's program. 00:01:25 ROBERT MICHLER, MD: Good evening, and welcome to the Montefiore Einstein Heart Center here in New York City. I'm delighted to share with you some of the extraordinary work that we're performing here at the Montefiore Einstein Heart Center in cardiothoracic surgery. This evening, we have a very special operation, and one that I think you'll find absolutely fascinating. I'm Robert Michler, and together with my partner and associate Dr. Samuel Weinstein, who's the director of our program in pediatric cardiothoracic surgery and adult congenital surgery, we will share with you Dr. Weinstein's operative techniques and thoughts on the management of patients with anomalous left coronary arteries. Dr. Weinstein, welcome. 00:02:17 SAMUEL WEINSTEIN, MD: Thank you very much, Dr. Michler. This evening, we're going to take a look at an operation on an 11-year-old girl who presented to the Montefiore Einstein Heart Center with an anomalous left coronary artery off the pulmonary artery, or ALCAPA. She presented to her pediatrician's office with fatigue, and a murmur was heard on an exam. An echocardiogram showed the anomalous coronary artery, which was confirmed on an angiogram prior to her surgery on December 11 th of I think we can go ahead and take a look at the procedure. Right away upon visualization of the heart, one notices the enlarged and engorged collateral vessels from the right coronary circulation feeding the left coronary

2 circulation. While they are seen here well on the anterior surface of the heart, these vessels extend all the way around the infradiaphragmatic surface as well to feed the left coronary circulation. The patient will be cannulated for bicable venous bypass so that if surgery's to be performed within the pulmonary artery, part of it can be done with the heart profused with venous inflow control. 00:03:25 ROBERT MICHLER, MD: So I see you've cannulated the aorta here, Sam, as well as the superior and inferior vena cava. 00:03:31 SAMUEL WEINSTEIN, MD: Correct. As well, there are snares placed around the right and left pulmonary arteries so that antegrade plegia can be given both down the aorta as well as directly down the pulmonary artery once the pulmonary arteries are snared. Here, the cross clamp is applied, the initial dose to be given antegrade through the aortic root. 00:03:54 ROBERT MICHLER, MD: So this is an important point, Sam. To protect the coronary artery that arises off of the pulmonary artery, you infuse cardioplegia directly into the pulmonary artery while snaring each of the left and right pulmonary arteries. 00:04:09 SAMUEL WEINSTEIN, MD: Correct. Otherwise, the runoff of the plegia results in poor preservation. While the -- while the right pulmonary artery is being snared down, plegia is given continuously through both aortic roots and pulmonary artery. Following complete arrest, the main pulmonary artery is opened and the defect is examined. 00:04:32 ROBERT MICHLER, MD: So here you're incising the pulmonary artery. 00:04:35 SAMUEL WEINSTEIN, MD: Correct. And here we can see that the coronary ostium arises all the way on the lateral aspect of the pulmonary artery. I think if we go ahead and play the procedure... we can see the coronary ostial -- the tip of the coronary ostial cannula giving plegia directly. The sinus of this vessel is on the nonfacing pulmonary sinus of the pulmonary artery, posterior non-facing sinus. 00:05:02 ROBERT MICHLER, MD: Is there a more common location? 00:05:04 SAMUEL WEINSTEIN, MD: Can we hold the tape here just one second? 00:05:06 ROBERT MICHLER, MD: Is there a more common location for that to arise? Is it mostly on that leftward lateral-facing sinus? 00:05:13 SAMUEL WEINSTEIN, MD: It might be more common to present in the facing sinus directly opposite the aorta. It poses a technical issue when it is in the opposing sinus or posterior non-facing sinus because it will be almost 180 degrees away from the aorta. 00:05:28 ROBERT MICHLER, MD: Understood. So let's play the tape again. At this juncture, you've -- you've opened the pulmonary artery, delivered cardioplegia, and you're giving retrograde now through the coronary sinus? 00:05:44 SAMUEL WEINSTEIN, MD: Yes. After the retrograde cannula's inserted, all subsequent doses are given in a retrograde fashion. Because the coronary ostium comes off lateral and exactly 180 degrees away from the aorta in the non-facing sinus, we decide here to proceed with a Takeuchi repair. The Takeuchi repair for

3 ALCAPA requires that an aortopulmonary window be performed in order to get oxygenated blood under systemic pressure through the pulmonary artery to this anomalous vessel. Here you see a 4-mm punch being used to create the aortotomy. The remainder of the aortopulmonary window adventitia is dissected free to allow the opposing aortotomy in the pulmonary artery to allow creation of the window. An anastomosis here will then be performed with 6/0 prolene suture as the first step in the repair, allowing a surgical AP window to bring oxygenated blood into the pulmonary artery. 00:06:44 ROBERT MICHLER, MD: So there's your incision in the pulmonary artery, and you've lined that up almost adjacent to the site where you put a punch into the aorta. 00:06:54 SAMUEL WEINSTEIN, MD: Correct. 00:06:55 ROBERT MICHLER, MD: And now you'll perform an anastomosis between those two structures. 00:06:59 SAMUEL WEINSTEIN, MD: Correct. Here we see the back wall being sewn first with a prolene stitch. 00:07:04 ROBERT MICHLER, MD: So what are some of the other surgical approaches to ALPACA? 00:07:09 SAMUEL WEINSTEIN, MD: The initial approaches were ligation of the coronary artery when profusion techniques weren't quite as sophisticated as they are today. While that did control the runoff from the coronary flow, there was an unacceptably high rate of sudden death postoperatively. Today, surgeons would prefer to perform a two coronary revascularization, and that can be done with a bypass graft in an older child or an adult or perhaps with a subclavian artery in a younger patient. Today, I think, in a younger child or in almost any patient, a congenital surgeon would prefer to perform either the Takeuchi repair, as we are doing today, or as we are showing today, versus the direct translocation or direct reimplantation of that coronary onto the aorta. Today, with the familiarity of coronary translocation with the arterial switch operation, this is probably the preferred approach. 00:07:59 ROBERT MICHLER, MD: I see. And what would you say are the best results. What do we see now in terms of long-term results with patients who've had a Takeuchi repair. 00:08:08 SAMUEL WEINSTEIN, MD: Long-term results with both the Takeuchi repair and direct translocation are excellent. They provide for repairs with native tissue that can grow with the patient, and long-term outcomes are in success of 90% in most large centers. 00:08:20 ROBERT MICHLER, MD: Excellent. With good preservation, good ventricular function. 00:08:24 SAMUEL WEINSTEIN, MD: That's the key. And that's really the key here in this operation. Because of her age and her long-standing presence of this anomaly, her collateral flow was so enormous that we had to cool her to 24 degrees to allow low flow to preserve the heart adequately. Almost at any time in the procedure, despite the heart being cross clamped, the continuous runoff of collateral flow into this coronary made visualization very difficult. 00:08:48 ROBERT MICHLER, MD: Understood. Shall we return to the operation?

4 00:08:52 SAMUEL WEINSTEIN, MD: Please. So here we've completed the aortopulmonary window and tying the anterior suture. 00:09:02 ROBERT MICHLER, MD: And this is the -- the anterior suture's tied there for the anastomosis, and now you must turn to redirecting the flow from that orifice of the coronary artery back to the aorta. 00:09:17 SAMUEL WEINSTEIN, MD: That's right. And you see here the sucker in the vessel itself needs to maintain its position or visualization for the operation is very challenging. In -- to help us with preservation, in addition to cooling the patient to 24 degrees Celsius, we add topical ice at intervals throughout the procedure. The baffle within the pulmonary artery will be performed with a 6-mm Gore-Tex graft that has been opened longitudinally with a small longitudinal piece taken out of it. This will allow the posterior wall of the baffle to be native tissue, the patient's own pulmonary artery, which should continue to grow with her as she gets older. 00:09:56 ROBERT MICHLER, MD: Go over that once more with us, Sam. That's an important point. Here we see the baffle going down into position, so explain the opportunity for growth in this conduit. 00:10:10 SAMUEL WEINSTEIN, MD: You can see as the baffle gets lower that it's really the anterior 180 degrees of a tunnel. The anterior aspect of the tunnel is made out of Gore-Tex, which obviously won't grow. It's going to direct the blood through that AP window, across the pulmonary artery, on the posterior surface of the pulmonary artery, all the way to the lateral left side of the PA, where the left coronary ostia arises. By leaving the back wall of this tunnel, or baffle, as native pulmonary artery tissue, it will continue to grow with the patient and should reduce the risk of coronary stenosis over time. This particular patient is already 11 years of age; the Gore-Tex graft itself is of 6 mm, so there's probably little likelihood here that there'll be residual stenosis. 00:10:55 ROBERT MICHLER, MD: Understood. Now, Sam, tell us about the pulmonary valve in these patients. You're working very close to the pulmonary valve. Any issues that the surgeon should be concerned about? 00:11:05 SAMUEL WEINSTEIN, MD: Absolutely. By running the baffle so close to the pulmonary valve, one has to make sure to stay above the commissural posts so as not to create pulmonary insufficiency. In addition, postoperatively, in the long-term, follow-up has suggested some of these patients develop a residual pulmonary stenosis. 00:11:23 ROBERT MICHLER, MD: Now, the pulmonary stenosis can be avoided simply with being aware of the commissural posts, or what can we do to reduce the risk of pulmonary stenosis in the future? 00:11:35 SAMUEL WEINSTEIN, MD: As we'll see here a little bit later in the procedure, we prophylacticly augment the pulmonary artery with a piece of pericardium in order to prevent this complication. 00:11:44 ROBERT MICHLER, MD: Any other valvular issues that the surgeon should be aware of? Long-term function of the mitral valve, for example? 00:11:51

5 SAMUEL WEINSTEIN, MD: That's an excellent question. The mitral valve is often incompetent to some degree in an ALPACA patient -- excuse me, an ALCAPA patient that presents acutely. This is thought to be due to ischemia to the left ventricular wall and anterior papillary muscle. It's a bit controversial right now. Some centers will do a mitral valve repair at the time of the coronary repair while other centers prefer to revascularize the heart, feeling that myocardial revascularization will allow improvement of mitral valve function. Long-term success is not affected by which repair you choose at the mitral valve. 00:12:26 ROBERT MICHLER, MD: Very good. So let's return back to the operation. It looks as though you've completed now the baffle. 00:12:31 SAMUEL WEINSTEIN, MD: Yes. And you can see here as we pull up on the sutures, you're going to be able to get a glimpse of how this baffle, or tunnel, lies on the back wall of the pulmonary artery or posterior surface and is going to bring blood from its right, where the patient's aorta is, over across the PA to the left side. Now, just to confirm the patency, we opt here to make a small aortotomy. You can see again the enormous collateral flow returning from this coronary with the heart cross-clamped results in blood exiting the aorta under pressure. And we're going to insert a Hagar dilator here just to make sure that the AP window is open and there's patency into the coronary. Again, you see the blood squirting out under pressure; this is just the passive venous -- excuse me, the passive coronary arterial flow. And the vessel there easily accepts the Hagar, and the aortotomy is closed again with a prolene suture. 00:13:29 ROBERT MICHLER, MD: So this is the aortotomy being closed. You've confirmed both visually and with a Hagar dilator that you have an -- a large, confluent passage from aorta to that anomalous coronary through the baffle. 00:13:44 SAMUEL WEINSTEIN, MD: Yes. And now attention is turned towards repair of the pulmonary artery. As we mentioned earlier, the incision here is carried inferiorly, and you can get a glimpse, again, of the baffle running posteriorly along the surface of the PA. we make the incis-- we extend the incision inferiorly and close the superior aspect. This will allow us to put a patch on the PA over the area of direct concern, which is the area directly over the surgically created baffle. And this will be performed with a piece of fresh pericardium. 00:14:15 ROBERT MICHLER, MD: So it appears as though you've openly widely the aor-- the pulmonary artery. Your initial incision was a transverse pulmonary arteriotomy? 00:14:26 SAMUEL WEINSTEIN, MD: Correct. The initial incision was transverse and a little bit superior than we would have wanted it to stay away from any potential injury to the coronary until its direct location could be ascertained. Now that we have an idea of exactly where the baffle is, we can cut a piece of pericardium, as you see here, and we directly place it over the tunnel itself while we're able to close the majority of the pulmonary artery primarily. 00:14:52 ROBERT MICHLER, MD: Now, your results with this operation, Sam, any issues that you've seen that are technical issues that you can advise the surgeons watching to help prevent either pulmonary insufficiency in terms of making sure that they're away from the pulmonary valve, for example, or you've just coached us on what we can do to prevent pulmonary stenosis. Any other thoughts with regard to how to manage that -- the pulmonary artery?

6 00:15:20 SAMUEL WEINSTEIN, MD: The Takeuchi repair is an excellent choice if the coronary ostium for the left coronary arises so far away that it can't be directly moved on to the aorta. If that occurs, the baffle should be attempted to be placed as far away from the pulmonary valve as possible. If this still is not possible, other options would be an external bypass graft with a mammary artery or a piece of vein, or one can excise the coronary with an extra button of tissue from the pulmonary artery to make an extended vessel and use that to directly sew onto the pulmonary artery. 00:15:52 ROBERT MICHLER, MD: Okay, very well. And here we're seeing the completion now in the operative procedure of that pericardial patch over the aorta, and I see that you've taken a clamp off and are doing this with the heart beating. 00:16:05 SAMUEL WEINSTEIN, MD: Right. As we're bicavally cannulated with the snares down, we've controlled the venous inflow, the pulmonary arterial repair is completed. Here we're checking hemostasis of the AP window just to make sure things are hemostatic before proceeding with the operation. The patient is re-warmed, loaded with milrinone and separates for bypass quite easily on a milrinone drip and decannulated after modified ultra-filtration. 00:16:29 ROBERT MICHLER, MD: Excellent. So this is obviously a technically demanding operation, and one that requires great skill, but also it requires great skill in evaluating the patient before surgery, because as you mentioned in your introduction, one of the challenges is whether the patients had left -- any evidence of left ventricular dysfunction. You've mentioned the possibility of mitral valve dysfunction as well. So tell us a little bit about what goes into your strategy and thinking when assessing left ventricular function in these patients. Is there a degree of left ventricular dysfunction that is too severe for you to consider as an operative candidate, and what might you do in trying to bring patients to surgery? 00:17:18 SAMUEL WEINSTEIN, MD: A lot of the left ventricular function is potentially recoverable in a patient with this anomaly. We often proceed with the surgery in the thought that direct revascularization will improve the patient at almost whatever status they're in. Patients presenting for surgery in an acute failure from left ventricular function or mitral valve insufficiency should be operated on with the backup of a left ventricular assist device postoperatively. Patients usually suffer an additional myocardial insult from the operation which often recovers within two to four days in most reported series. Most patients who even require an LVAD following this operation can be -- not only be weaned from the device but extubated and discharged home from the hospital. 00:17:58 ROBERT MICHLER, MD: So how would you decide to potentially sequence this from the operation to a balloon pump, for example, and then to an LVAD? Or do you base this on size, availability of devices? Do you even consider ECMO in patients with severe left ventricular dysfunction preoperatively? Give us a little bit of your algorithm for how you decide which one to use and do you stage it up depending on body size, for example? 00:18:31 SAMUEL WEINSTEIN, MD: Well, obviously, any decision is -- pediatric heart surgery is limited with the size of the patient. We always attempt to wean the patient from bypass and our usual amount of inotropic support. If we are failing to do so or requiring high doses, if the patient is larger, a balloon pump can be considered. More commonly, the size of the patient dictates that a left ventricular assist device is

7 necessary due to the size of the femoral vessels. If this is the case, the LVAD is a superior device then ECMO in this particular situation because the injury is usually limited directly to the left ventricle. The right ventricle is usually spared. 00:19:10 ROBERT MICHLER, MD: So in this particular patient, Dr. Weinstein, you saw an improvement in left ventricular function after the operative procedure. Tell us what you saw intraoperatively and what you would expect to see over the weeks and months after the operation. 00:19:25 SAMUEL WEINSTEIN, MD: This patient had mild to moderate mitral valve regurgitation and mild to moderate depression of her left ventricular function. As with most patients following this operation, we would anticipate, well within a year, recovery of both of these elements. Most patients, when revascularized, if followed, will not do well acutely within the first few days in terms of an immediate improvement, but over the course of months to a year, will see clear recovery of cardiac function. 00:19:52 ROBERT MICHLER, MD: Very good. We have a question from the audience. First: do any special concerns have to be taken into account by the anesthesiologist during the repair of this lesion? 00:20:07 SAMUEL WEINSTEIN, MD: That's a very good question. I think the usual meticulous technique to patients with low cardiac output and careful not to unload them to rapidly would be the best approach. 00:20:17 ROBERT MICHLER, MD: One of the individuals who's ed us has -- would like us to comment that her daughter had this procedure 13 years ago at the age of 13 weeks and that she continues to do very well. In the long-term, what is your experience with regard to stenosis of the pulmonary artery after the Takeuchi repair? 00:20:40 SAMUEL WEINSTEIN, MD: The stenosis of the pulmonary artery should be in a minority of instances, perhaps 10-20%. If it does occur, though, it can be relatively easily treated, either in a catheterization lab with pulmonary arterial balloon angioplasty or even a simple, straightforward surgical technique to augment this vessel. Overall, outcomes for patients in this category are extremely good, and patients should expect a success of over 90%. 00:21:08 ROBERT MICHLER, MD: Jackie, thank you for your question, and as a follow-up, let me ask Dr. Weinstein to comment on other things that should be followed in patients who have had this type of surgery. 00:21:21 SAMUEL WEINSTEIN, MD: As the left ventricular function is really the key here, longterm we follow the patients for their exercise capacity as well as their mitral valve function. New York Heart Association for failure classification and long-term outcome parameters are followed closely, and the patients stay in the medical system with qualified cardiologists. 00:21:41 ROBERT MICHLER, MD: Tell us about the other coronary anomalies that are associated with this particular problem. 00:21:48 SAMUEL WEINSTEIN, MD: The ALCAPA is the most common of the coronary anomalies. The right coronary artery itself can come off the pulmonary artery; it's much less common and it also doesn't present with such severity. The right coronary

8 artery or the left coronary artery themselves can come off the opposite sinuses, so that the right comes off the left or the left will come off the right side. A lot of these things patients may have, you may not know about them because they don't pose problems. In the instances where these vessels come from the abnormal location and they cross in between the great vessels or in between the pulmonary artery and the aorta, they can get compressed and can cause myocardial ischemia, and this can present itself as a heart attack in an older adolescent, young adult, or even an elderly person. 00:22:34 ROBERT MICHLER, MD: Are there other associated congenital anomalies that we might see in patients who have this lesion? 00:22:41 SAMUEL WEINSTEIN, MD: Actually, it turns out that the coronary anomalies in patients usually present as isolated defects without other cardiac or other congenital issues. 00:22:50 ROBERT MICHLER, MD: Now, this particular child's symptoms were what brought the patient to the attention of the doctors. Share with us a little bit about this patient's symptoms and how the patient is doing now, and were these symptoms typical of patients with ALCAPA? 00:23:13 SAMUEL WEINSTEIN, MD: When patients present as an infant, it looks a little bit different than they present as ours did as an 11-year-old girl. Our patient was able to communicate that she felt fatigue and some chestfulness on exercise. When patients present as did Jackie's daughter, at 13 weeks of age, it can look as though the patient is ped-- the patient is feeding poorly or has very poor cardiac output. This is called Bland-Garland syndrome. Otherwise, as the patient gets older, they can look like they're having a heart attack. Our patient's fatigueness and shortness of breath will probably decrease over time as she's now revascularized. She's only about six to eight weeks after surgery, so she's just recuperating from the operation itself. 00:23:57 ROBERT MICHLER, MD: Very good. Well, Dr. Weinstein, this was certainly a superb demonstration of a technically demanding and challenging operation. On behalf of the Montefiore Einstein Heart Center and our patients, I want to thank you for an excellent demonstration, and if you have any further comments or a particular pearl you might be able to share with the audience about this lesion, it would be much appreciated. I understand we have another several questions coming in via the Internet, so if you would share with us a particular pearl, a surgical pearl, perhaps one from a technical perspective, and also something for the medical physicians to address. 00:24:49 SAMUEL WEINSTEIN, MD: I think in approaching the lesion, it's very important to be at a sophisticated medical center that has all the resources available to treat a complicated lesion such as an ALCAPA. Surgically, I think the Takeuchi approach is a wonderful option when the surgeon is either uncomfortable or unable to perform direct translocation. 00:25:09 ROBERT MICHLER, MD: We have a question from a surgeon in the audience asking about the ice slush that they saw on the surface of the heart, the topical ice, wondering whether this can cause frostbite to the heart or injure the phrenic nerves. 00:25:27

9 SAMUEL WEINSTEIN, MD: Ice can potentially injure the phrenic nerves. When we use topical ice, we tend to leave it only on the anterior surface of the heart, but we also use phrenic pad protectors on the left side. We have not had experience seeing frost injury to the myocardium when using ice, and we have used it in cases such as this when there's been a lot of collateral coronary flow and we're worried about preservation. This particular patient had no change in her ventricular function postoperatively but did have some improvement already on her 10-day discharge echocardiogram. 00:26:00 ROBERT MICHLER, MD: Excellent. Well, once again, thank you for joining us this evening at the Montefiore Einstein Heart Center in New York City for Dr. Samuel Weinstein and his technical advise in the management of patients with anomalous left coronary artery from the pulmonary artery. What we've seen is a review of the Takeuchi repair performed by Dr. Weinstein in a patient who is 10 years old and is now recovered very nicely from their operative procedure here at the Montefiore Einstein Heart Center. Good night and thank you. 00:26:41 ANNOUNCER: Thank you for tuning in to this live panel discussion of an anomalous coronary artery procedure presented by the Montefiore Einstein Heart Center. To obtain more information, to make an appointment, or make a referral, please click the appropriate buttons on your screen. Montefiore Einstein Heart Center: advanced care, visionary thinking. 00:27:12 [ end of program ]