Epicardial and endocardial approaches to LAA closure
Top: Moussa Mansour, MD
Bottom: Vivek Reddy, MD
Epicardial techniques present advantages over some aspects of endocardial devices, as long as patients have anatomies that do not preclude their use, but more data across the board regarding efficacy and safety is still needed, delegates will hear this morning in a session dedicated to the topic of left atrial appendage (LAA) closures.
Discussing the endocardial approach will in particular be Vivek Reddy (Director, Cardiac Arrhythmia Service, Mount Sinai School of Medicine, New York, USA), while Moussa Mansour (Massachusetts General Hospital, Boston, MA, USA) will concentrate on the epicardial aspects. They spoke to Boston AF Symposium News ahead of the meeting to discuss both techniques, and what we can hope to learn in the near future in order to improve patient outcome.
“The role of left atrial appendage occlusion has become a hot topic and it is a very rapidly developing area in atrial fibrillation,” began Dr. Mansour. “Many patients cannot take blood thinners for a variety of reasons, and while the novel anticoagulants are certainly easier to use than warfarin, despite the new choices, we still are faced with difficulties in managing patients with atrial fibrillation, such as a high risk of stroke and high risk of bleeding.”
Dr. Mansour underlined that while most of the experience so far in this arena has been seated with the endocardial devices, patients with contraindication to anticoagulation cannot be treated endocardially, because the devices require the use of anticoagulants. Conversely, epicardial devices do not require any anticoagulation – even for a short time after the procedure. In addition, they offer further benefit in that epicardial devices negate the need to implant a permanent device, as with the endocardial approach.
Leaving no permanent implant within the heart is a clear advantage provided that the closure is effective and the region in question can be reached, as Dr Reddy explained: “The advantage of the epicardial approach is that you leave just a suture behind, so there is no device left inside the vascular system. And that’s certainly attractive and has some potential advantages.”
But not all patients possess anatomies that mean they are eligible for the epicardial procedure, as Dr Reddy described: “The downside is that you need to get pericardial access. There is a certain percentage of patients who have had previous cardiac surgery, or who are just not eligible for epicardial closure, but that’s a relatively small percentage of the whole. In the remaining population, the majority of them are eligible from the anatomic perspective; and there is probably about five to ten percent of the population that have unusual appendicial anatomy that precludes being able to do the suture procedure.”
Dr. Mansour echoed this statement: “If a patient has an appendage with a tip diving beyond the pulmonary artery – which makes it not amenable to the epicardial approach – a patient like this may be a better candidate for an endocardial approach,” he said.
With all of this in mind, it is clear that there is a place for both types of devices in the field. But what of surgical approaches? “I think we will see less and less need for surgical ligation, unless the patient is going for concomitant heart surgery,” said Dr. Mansour.
He expanded on this concept: “We have had a patient recently where he had a clot in the appendage and there was nothing we could do about it so we took him to surgery, so that would be one niche area.”
Within each of their presentations, Dr. Mansour and Dr. Reddy will provide an overview of a number of devices from the epicardial and endocardial fields, respectively. Specifically, Dr Mansour will discuss the two clinically available epicardial devices thus far: “One of them has been used for more than a year in the United States, and in Europe, and the other one has only been used in Europe for a very small number of patients,” he said.
Moving on to issues of safety and effectiveness, Dr. Reddy compared the knowledge gaps of different devices, noting that epicardial and endocardial approaches are equal in terms of performing the procedure itself. More clinical trials would certainly help to define the clinical issues and to highlight interesting cases, yet experience is a necessary ingredient whatever procedure is being carried out, as Dr Reddy explained: “On the effectiveness side, we have no data on epicardial closure. On the safety side, there are complications that are associated with pericardial access, and that will occur to a certain extent. So I think that’s something that we have to worry about.”
Dr. Reddy stressed that while there is a good deal of data available for many of the endocardial devices, chiefly in terms of efficacy, there is still a great need for more, and trials would be a particularly important component to gather more information on safety in particular. Similarly, as real-world exposure with epicardial devices begins to accumulate more and more each day, we are now at the stage where we can begin to more effectively evaluate the epicardial approach. As such, Dr Mansour will present encouraging preliminary results stemming from the use of these devices in his presentation.
Concluding with the reminder of the importance of such techniques – namely, in reducing the stroke risk and the reliance on anticoagulant therapy that be- come increasingly important with increasing age, Dr Reddy said: “I think the population at greatest clinical need are the elderly patients with atrial fibrillation. They are the ones that are the very highest risk for stroke. They are the ones that tolerate blood thinners, whether it’s warfarin or one of the new agents. There is a fall risk and other issues related to elderly patients. So the most critical thing is to have procedures that are quick, that are very safe, and that reduce the risk of stroke – I think that’s the avenue of research that’s probably the most useful.”
Dr. Mansour added: “I think it remains to be seen which patient will benefit more from which procedure. This field is starting to be defined now. I don’t think it’s clear yet who will benefit from endocardial procedures, and who will benefit from epicardial procedures. I think over the next year or so we will see some reports to try to define this area better, and maybe there will be some anatomic consideration that can guide us to which approach we use.”