Background:

The new Amplatzer Steerable Delivery Sheath is an enhanced delivery system designed to improve ease-of-use and procedural results of left atrial appendage closure (LAAC) in a broad range of anatomies. It is speculated that the new steerable delivery sheath can shorten procedure time and enhances efficiency of LAAC procedures. However, currently no comparison to the previous sheath is available.

Objectives:

We aimed to compare procedural results after switching our  LAAC program at a tertiary care center with the Amulet device to the Steerable Delivery Sheath, with a control group of LAAC employing the standard Amulet implantation sheath.

Methods:

The first n=32 consecutively treated patients at our site using the Amulet device with the Steerable Delivery Sheath were included in the retrospective analysis. As a control-group, n=39 consecutive patients treated with the Amulet device prior to the switch to the new sheath were used. Data were prospectively collected and analyzed from inhospital patient electronic databases, as a subgroup analysis of the HANSE LAAC Registry. 

Results:

Baseline characteristics were comparable between the groups (steerable sheath vs. control group: age :80±7.2 vs. 79±7.6 years, p=0.8; female gender 37.5 vs. 17.9%, p=0.1). The CHA₂DS₂Vasc-Score was comparable (steerable sheath vs. control group: 4±1.2 vs. 4±1.5, p=0.1). We observed differences in the HAS-Bled-Score (steerable sheath vs. control group: 3.5±0.1vs. 3.8±0.7, p=0.03*), history of heart failure (steerable sheath vs. control group: 65 vs. 31%, p=0.004*) and renal failure with dialysis (steerable sheath vs. control group: 22 vs. 3%, p=0.01*),

Implantation was successful in all patients (100%) in both groups with implantation of multiple device sizes according to the instructions for use (steerable sheath group vs. control group: 34mm 0 vs. 5.1%, 31mm 16 vs. 10.2%, 28mm 21vs. 28%, 25mm 37.5 vs. 28.2%, 22mm 19 vs. 18%, 20mm 3 vs. 2.5% 18 and 16mm 0 vs. 2.5%). Contrast use and fluoroscopy time were numerically higher in the steerable sheath group (steerable sheath vs. control group:  contrast use 70±23 vs. 55±50 ml, p=0.09, fluoroscopy time 12.7±4.6 vs. 10.2±6.6, p=0.3). We assumed a learning curve and analyzed contrast use and fluoroscopy time during the first three months with the steerable sheath and >three months. Fluoroscopy time and dose decreased after 3 months, but the contrast use remained unchanged. 

Complete sealing rate was high in both groups (steerable sheath vs. control group 97 vs. 95%, p>0.9). We observed no change to another device in the steerable sheath group as compared to 2 changes to another size the control group (0 vs. 5.1%, p=0.5). The pericardial effusion rate was low (steerable sheath vs. control group 3.1 vs. 2.5%, p>0.9), with one observed pericardial tamponade in the control group (steerable sheath vs. control group 0 vs. 2.5%, p>0.9). Periprocedural complication rate was low, without any periprocedural stroke, vascular complications or death in both cohorts. 

Conclusions

LAAC with the Amplatzer Amulet stearable delivery sheath is feasible with favorable periprocedural outcomes. Fluoroscopy time and dose suggest a learning curve with the new sheath.