Percutaneous Left Atrial Appendage Closure: How Easy Can it Get?

Percutaneous left atrial appendage (LAA) and patent foramen ovale (PFO) closure are the two preventive procedures in interventional cardiology.¹ Unlike PFO closure, which is the safest technique in interventional cardiology, LAA closure is among the more intricate and complication-prone catheter-based interventions. This creates a situation where the patient informed about LAA closure more often opts for the alternative medical treatment than the patient informed about PFO closure. On top of that, the interventional cardiologist typically also shows reservation when it comes to LAA closure, but not when it comes to PFO closure. With a therapeutic procedure, the patient leaves the hospital usually improved; with a preventive procedure, the patient will leave the hospital at best unchanged. If complications arise, it is far more difficult to explain and defend the deterioration of a patient’s state after a preventive procedure than after a therapeutic procedure. It is intuitively assumed that the latter simply had to be done.

With this background, it is understandable that a cardiologist responsible for LAA closure will take no shortcuts. Then again, the data accumulated with LAA closure mandate that LAA closure be offered to every patient with atrial fibrillation at least as an alternative option to life-long oral anticoagulation. The mortality benefit already emerging after only a few years due to reduced bleeding problems, as well as comparable or only slightly inferior embolism protection, cannot be ignored.² While the mortality benefit might no longer be apparent when comparing LAA closure with non-vitamin-K antagonist oral anticoagulants, LAA closure still appears competitive.³

About 9 out of 10 patients will opt for the blood thinner pill rather than LAA closure, at least for the time being, after they have been informed that the intervention carries a risk of about 4% for a significant complication and that open-heart surgery will become necessary in 1%, while continuing on the pill infers a bleeding risk of about 2% per year. Nonetheless, the high prevalence of atrial fibrillation still renders LAA closure a common procedure. This imposes the economization of the resources invested into each case.

To that end, in this issue of the Journal of Invasive Cardiology, Hammersley and colleagues propose the elimination of preliminary imaging.⁴ This does not yet make it a true ad hoc procedure, as proposed previously,⁵ but will allow the one-stop shop treatment of a patient admitted for cardiac catheterization in the realm of atrial fibrillation in whom the issue of LAA closure is raised for the first time, provided transesophageal echocardiography (TEE) and perhaps some anesthesia support are available. 

The authors list the situations where the lack of preliminary imaging would be regretted: (1) The patient has lost the LAA during a previous surgery and nobody is aware that this has happened. This is an unlikely scenario that has never occurred during my experience with over 1000 LAA closures. (2) Angiography of the LAA shows features that preclude an attempt at closure and that would have been identified by prior computed tomography (CT) or TEE. Again, a scenario that has yet to be encountered or at least described in a report. There is virtually no anatomical situation that precludes the implantation of an Amplatzer-type LAA occluder to at least partially close the LAA. The Watchman occluder admittedly is a little less versatile. (3) A thrombus is detected in the LAA and the procedure must be abandoned. With the technique proposed here, where TEE is performed before even inserting catheters into the patient, let alone into the left atrium, all that is lost compared to a protocol with prior CT or TEE is catheterization laboratory time. If the procedure is performed without TEE guidance,³ a thrombus will only be detected after transseptal passage and injection of contrast medium (performed from a safe distance to the LAA, of course). This situation was encountered in about 5% of patients in our experience and it is debatable whether the risk of the transseptal puncture was justified in these cases. Make no mistake, aside from the inconvenience, TEE also carries a small risk itself.

I tend to sum up the discussion about this issue with my patients with the statement that if I was in their shoes, I would prefer LAA closure over life-long oral anticoagulation. Yet, I would like to start the day after the procedure. They then tend to postpone the day of the procedure. This situation will not fundamentally change, as working in the left atrium and LAA with thin free walls will never be a home-run intervention like PFO closure. Notwithstanding, interventional cardiologists generally disliking this tricky preventive intervention will have their arms twisted to perform it regularly. Sending the patient to unnecessary preliminary imaging only buys time and is unlikely to reveal contraindications, bailing out the operator from performing an unpopular but justified intervention.

References

1. Meier B. Percutaneous closure of the patent foramen ovale, easy does it. Catheter Cardiovasc Interv. 2015;86:113-114.
2. Reddy VY, Sievert H, Halperin J, et al. Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial. JAMA. 2014;312:1988-1998.
3. Nietlispach F, Gloekler S, Krause R, et al. Amplatzer left atrial appendage occlusion: single center 10-year experience. Catheter Cardiovasc Interv. 2013;82:283-289.
4. Hammersley D, Podd S, Gomes A, et al. Feasibility of left atrial appendage occlusion without preprocedural transesophageal echocardiography or CT scanning. J Invasive Cardiol. 2015 October 15 (Epub ahead of print).
5. Nietlispach F, Krause R, Khattab A, et al. Ad hoc percutaneous left atrial appendage closure. J Invasive Cardiol. 2013;25:683-686.

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From the Cardiovascular Department, University Hospital, Bern, Switzerland.

Disclosure: The author has completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Meier reports research grants to University Hospital and speaker and proctor honoraria from St. Jude Medical.

Address for correspondence: Bernhard Meier, MD, FACC, Professor and Chairman of Cardiology, Cardiovascular Department, University Hospital Bern, 3010 Bern, Switzerland. Email: bernhard.meier@insel.ch