# Procedural Comparison of the Amulet Versus Watchman Devices: A Single Center’s 'Change of Heart'

## TL;DR

This study compares two heart devices for blocking the left atrial appendage and finds that one causes higher radiation exposure during implantation.

## Contribution

The study provides a direct comparison of procedural outcomes between the Watchman and Amulet devices for left atrial appendage occlusion.

## Key findings

- Amulet device implantation resulted in significantly higher radiation dose compared to the Watchman device.
- No significant differences were found in procedural time or contrast use between the two devices.
- Procedure time averaged 56.71 minutes overall, with no significant variation between devices.

## Abstract

Background

The recommendation level for left atrial appendage occlusion (LAAO) via device implantation has increased in the most recent American College of Cardiology (ACC) guidelines, resulting in an increase in implantation rates. Our center had the unique experience of originally implanting Watchman deviceTM (Boston Scientific, Marlborough, MA, US) devices from 2017 to 2021 and abruptly switching to implanting Amplatzer AmuletTM (Abbott Cardiovascular, Plymouth, MN, USA) devices from 2021 to the current day. This sudden switch between devices created a unique opportunity for direct comparisons of the two LAAO devices. Our study aimed to compare the differences between these two devices regarding procedural time, radiation dose, and contrast use.

Methods

Several patients (n=1262) underwent LAAO implantations from 2017-2024 at our center. We performed simple random sampling to select 200 patients that received the Watchman devices and 200 patients that received the Amulet devices. Demographic information, procedural time, radiation dose, and contrast doses were collected for all of them. Student’s t-tests were performed on continuous variables for statistical analyses.

Results

The average procedure time overall was 56.71 minutes. The average radiation dose of patients undergoing the Watchman device implantation was 167.5 mGy (95% CI: 140.9-194.1) and 247.0 mGy (95% CI: 201.4-286.7) for the Amulet device (p=0.001). The average procedure time did not differ as it was 52.4 minutes (95% CI: 48.7-56.1) for the Watchman device implantation versus 56.1 minutes for the Amulet implants (95% CI: 52.1-60.1; p=0.183). The average contrast dose also did not differ, as patients undergoing the Watchman device implantation used 31.3 cc (95% CI: 27.8-34.8), whereas it was 34.5 cc (95% CI: 31.4-37.7; p=0.176) with the Amulet device.

Conclusion

There was a significantly higher radiation dose associated with the implantation of the Amulet versus the Watchman devices. There were no significant differences between procedural time or contrast use between the two devices.