Collaborative Experience Using the LARIAT System for Left Atrial Appendage Closure

Atrial fibrillation carries a fivefold increased risk of stroke.^1,2 Antithrombotic therapy is effective in reducing stroke risk,^2,3 but with oral anticoagulation comes an increased risk of bleeding. Left atrial appendage (LAA) closure is another means of reducing thromboembolic risk⁴ and is indicated in patients intolerant of anticoagulant therapy. Since 2009, the LARIAT (SentreHEART) has been FDA approved for soft tissue closure and utilized as a method of percutaneous LAA closure in over 2,000 cases worldwide (personal communication with SentreHEART). Via epicardial and endocardial (transseptal) access, magnet-tipped “finder” wires are placed to form a rail over which a nonabsorbable polyester suture is delivered to ligate off the appendage. A feasibility study, PLACE II, was recently published and showed an approximate 96% incidence of effective closure and a low major complication rate.⁵ Specifically, pericardial effusion incidence was low at 3.3%, no patients required emergent surgery, and no intra-atrial clots or thromboembolic events were identified.⁵ This article is intended to share our early experience with LARIAT ligation of the LAA in two patients at high risk of stroke but who were unable to take anticoagulants. 

Case Descriptions

Patient #1 was a 78-year-old male with intermittent persistent atrial fibrillation and flutter. He had previously undergone pulmonary vein isolation and cavotricuspid isthmus ablation as well as dual-chamber pacemaker implantation for sick sinus syndrome. He also had hypertension and diabetes mellitus (CHA₂DS₂-VASc score of 3). Importantly, he had a history of spontaneous subarachnoid hemorrhage with no evidence of underlying aneurysm, and not while taking an anticoagulant. He had been taking aspirin 81 mg daily at the time of referral for LAA closure.

Patient #2 was a 65-year-old female with persistent atrial fibrillation, hypertension, diabetes mellitus, and gastric ulcers, with a history of partial gastrectomy for bleeding from a perforated ulcer (CHA₂DS₂-VASc score of 4). She was also taking aspirin 81 mg daily.

Prior to the procedures, contrast CT images of the LAA were reviewed by the team and with staff from SentreHEART to confirm suitability of the patients’ left atrial appendages for LARIAT closure. Common reasons for deferral include LAA thrombus, history of cardiac surgery, history of chest radiation, LAA widest diameter >4.0 cm, or if the LAA apex is directed superiorly behind the pulmonary artery.⁵ A third potential case was deferred, as our patient’s LAA measured over 4.0 cm (the upper margin for safe use of the LARIAT is 4.0 cm). 

Outpatient transesophageal echocardiography (TEE) was performed approximately 1 week in advance of the procedures at the time of preprocedure workup to confirm the absence of a left atrial thrombus.

The procedures were performed under general anesthesia with a cardiothoracic surgeon present and a cardiopulmonary bypass team at the ready. A TEE probe was placed and maintained throughout the duration of the procedures. Survey of the LAA immediately after anesthesia induction confirmed absence of clots (Figures 1 and 2). Femoral venous access was utilized for introduction of intracardiac catheters, and blood pressure was continuously monitored via radial artery catheter.

Pericardial access was obtained using a Tuohy needle with an anterior approach using left lateral imaging of the cardiac borders. Microinjections of contrast were used to visualize tenting of the pericardium as the needle was advanced into the pericardial space. A 0.035” J wire was introduced, and once pericardial location was confirmed via fluoroscopy and TEE, a 13 French (Fr) introducer sheath and additional J wire for “backup” access were placed in the pericardial space.

Transseptal puncture was performed next. Heparin was administered with an ACT goal >300. With the aid of TEE, fluoroscopy, and pressure monitoring, a RF needle (Baylis Medical) was advanced into the left atrium using the SL1 (St. Jude Medical) long sheath.

LAA angiograms were performed with iodixanol (Visipaque, GE Healthcare) via the SL1 sheath. During case #2, there was difficulty reaching the most anterior lobe of the LAA. A quadripolar diagnostic catheter was inserted and formed a “rail” over which we could carefully guide the SL1 anteriorly. The endocardial wire, preloaded within a balloon catheter, was inserted into the SL1 sheath to a position in the most anterior lobe of the LAA. The balloon was advanced and inflated with TEE guidance at the os of the LAA. 

The epicardial wire was advanced via the pericardial sheath until the two magnets “kissed,” sandwiching LAA tissue between them. With the wires fixed, the LARIAT was fed over the epicardial wire and over the neck of the LAA. Position was confirmed  by balloon inflation (Figure 3a). The LARIAT was closed, and closure of the LAA was confirmed with TEE and another contrast injection from the SL1 (Figure 3b). After retraction of the deflated balloon catheter and endocardial wire, the suture was deployed and tightened with the TenSURE^™ suture tightener (SentreHEART). Another contrast injection and TEE confirmed ligation of the LAA and no flow from the LAA. The endocardial tools were pulled back to the right atrium.

The LARIAT loop was then opened, removed from the pericardium along with the epicardial wire, and the suture was cut. The pericardial sheath was exchanged for an 8 Fr pigtail catheter, which was connected to a drainage bag.

Each patient was observed in the hospital following the procedure. The pericardial drain was removed the next day. Serial transthoracic echocardiograms did not show any pericardial effusion. Patient #2 was discharged home on post-operative day 2. Patient #1 remained in the hospital until post-op day 3 because of pericarditis, for which he received a single dose of intravenous methylprednisolone, followed by colchicine and non-steroidal analgesics. He was in sinus rhythm on the day of his procedure but reverted to atrial fibrillation on the day of discharge.

Each patient was seen in follow-up approximately 14 days after the procedure. Patient #1 remained in atrial fibrillation and complained of fatigue. A limited echo showed no effusion. Therefore, he was scheduled for a TEE-guided cardioversion, but was in sinus rhythm on the day of the cardioversion so the TEE was deferred. He was continued on aspirin. 

Conclusion

Percutaneous left atrial appendage ligation utilizing the LARIAT Suture Delivery Device is a fascinating and feasible procedure for LAA obliteration. We have approached the procedure at our institution as a collaborative effort between specialists in electrophysiology, echocardiography, anesthesia, and cardiothoracic surgery. From a procedural standpoint, our first two cases, which were the first in North Carolina, went smoothly, but we were also prepared for uncontrollable bleeding. We view the LARIAT as an important option, along with surgical ligation and forthcoming endocardial devices (such as Boston Scientific’s WATCHMAN), for providing stroke prophylaxis in patients unable to take oral anticoagulants.⁶

References

1. Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke. 1991;22:983-988.
2. Camm AJ, Yip GYH, De Caterina R, et al. 2012 Focused update of the ESC Guidelines for the management of atrial fibrillation. Eur Heart J. 2012;33:2718-2747.
3. Hart RG, Pearce LA, Aguilar MI. Meta-analysis: antithrombotic therapy to prevent stroke in patients who have nonvalvular atrial fibrillation. Ann Intern Med. 2007;146:857-867.
4. Blackshear JL, Odell JA. Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation. Ann Thorac Surg. 1996;61:755-759.
5. Bartus K, Han FT, Bednarek J, et al. Percutaneous left atrial appendage suture ligation using the LARIAT device in patients with atrial fibrillation: initial clinical experience. J Am Coll Cardiol. 2013;62:108-118.
6. Holmes DR, Reddy VY, Turi ZG, et al.; PROTECT AF Investigators. Percutaneous closure of the left atrial appendage versus warfarin therapy for prevention of stroke in patients with atrial fibrillation: a randomised non-inferiority trial. Lancet. 2009 Aug 15;374(9689):534-42.

Disclosures: The authors have no conflicts of interest to disclose regarding the content herein.