Cardiac Plug Shows High Success, Low Complication Rate for LAA Closure

Download this article's Factoid (PDF & PPT for Gold Subscribers) 

Percutaneous closure of the left atrial appendage (LAA) with a cardiac plug device is associated with a high rate of procedural success and low rates of cardioembolic and bleeding complications in patients with nonvalvular atrial fibrilation (A-fib) who have contraindications to anticoagulant therapy, according to results of a study published online May 15, 2013, ahead of print in the Journal of the American College of Cardiology.

Researchers led by Josep Rodés-Cabau, MD, of Laval University (Quebec City, Canada), studied 52 such patients who underwent LAA closure with the Amplatzer Cardiac Plug (St. Jude Medical, Minneapolis, MN) at 7 Canadian centers. The plug consists of a self-expandable device with a distal lobe and proximal disc connected by an articulating waist.

Contraindications to anticoagulant therapy in the cohort included:

• Bleeding (intracranial hemorrhage 34.6%, gastrointestinal bleeding 23.1%, spontaneous hematoma of abdominal muscles 13.5%, otorhinolaryngological 7.7%, and respiratory 5.8%)
• INR lability (3.8%)
• High risk of fall (1.9%)
• Warfarin allergy (1.9%)
• Severe anemia (1.9%)

Few Periprocedural Complications

The procedure was successful in all but 1 patient (98.1%). No deaths or strokes occurred during hospitalization, and the rate of periprocedural complications was low and included device embolization (1.9%), transient ischemic attack (1.9%), and pericardial effusion (1.9%).

At mean follow-up of 20 months, the observed annual rates of stroke, thromboembolic events, and major bleeding were lower than expected (table 1).

Table 1. Cerebrovascular and Bleeding Events^a

^a P < 0.001 for all.

In addition, survival curves at 2 years showed high rates of freedom from death (97.5%), stroke (94.2%), and major bleeding (91.6%).

Among patients who experienced mild intradevice and peridevice leak (1.9% and 11.5%, respectively), all but 1 had their leaks disappear by 6-month follow-up. A total of 5 patients with no leak immediately after the procedure had mild peridevice leak at 6-month follow-up, resulting in a 16.2% rate of residual leak. Low LVEF was associated with the occurrence of new peridevice leak at 6-month follow-up (P = 0.016). No patients with residual leaks experienced cardioembolic events, and there were no instances of device thrombosis or late device embolization.

Antiplatelet therapy at last follow-up consisted of:

• Aspirin (61.5%)
• Clopidogrel (11.5%)
• Aspirin plus clopidogrel (17.3%)
• None (9.6%)

Residual Leak Risk Low, Clinically Insignificant

The study authors note that the 16.2% rate of residual leak seen in the study is lower than what has been previously reported for LAA closure with the Watchman device (32%; Boston Scientific, Boston, MA) or the device employed in the PLAATO trial (75%; ev3, Plymouth, MN), which is no longer available. They suggest the disc’s design may “[contribute] to a better sealing of the LAA.”

Development of peridevice leak over time, which occurred in 5 patients, has previously been reported with the Watchman device, they add, and may be related to “incomplete device endothelialization or some degree of device undersizing without periprocedural residual leak due to LAA contraction immediately after the implantation.

“Also, the fact that a low LVEF was associated with peridevice leak suggests that changes in the left atrial dimensions over time might play a role in the occurrence of these late leaks,” Dr. Rodés-Cabau and colleagues write. However, they point out that presence of mild residual leaks was not associated with cardioembolic events in this study or others.

Anticoagulation Remains Standard of Care

In an editorial accompanying the study, Zoltan G. Turi, MD, of Cooper University Hospital (Camden, NJ), notes that while the report “is a welcome addition to the scant data published on the [cardiac plug] thus far,” it suffers from several limitations. The study was not randomized, has limited data and duration of follow-up, and had no central core lab, clinical events committee for adjudication, or data safety monitoring board.

Although the plug is a familiar platform for operators, it is “problematic” that the device has been touted as being safe for use without anticoagulation since there remains a dearth of evidence on which to base that claim, Dr. Turi said.

He notes that clinicians should exercise caution when selecting patients for newer technologies such as the cardiac plug until more solid evidence is available.

“Until then, although long-term anticoagulation is cumbersome and has its own significant (but well established) toxicities, for those who are appropriate candidates it remains the best studied approach as well as the standard of care,” he concludes.

Study Details

Mean age and median CHADS2 score were 74 ± 8 years and 3, respectively. A transthoracic echocardiogram was performed 24 hours after the procedure in all patients.

 

---

Sources:
1. Urena M, Rodés-Cabau J, Freixa X, et al. Percutaneous left atrial appendage closure with the Amplatzer cardiac plug device in patients with non-valvular atrial fibrillation and contraindications for anticoagulation therapy. J Am Coll Cardiol. 2013;Epub ahead of print.

2. Turi ZG. The assault on the left atrial appendage in perspective. J Am Coll Cardiol. 2013;Epub ahead of print.

 

 

Related Stories:

• PROTECT AF: 4-Year Results Show Superiority of Watchman Over Warfarin for A-fib
• Novel Devices Provide Options for LAA Therapy
• Watchman Device for LAA Closure Provides Net Clinical Benefit vs. Warfarin in A-fib Patients