Utilization and outcomes of protamine after percutaneous left atrial appendage occlusion

The aim of this study was to describe the use pattern and outcomes of protamine administration for heparin reversal among sites performing percutaneous left atrial appendage occlusion (LAAO).

We identified 45,135 patients who underwent LAAO at 243 hospitals participating in Vizient® Clinical Database between January 1, 2016 and December 31, 2021. Patients were stratified according to protamine administration after the procedure. Outcomes of interest included vascular complications, major bleeding, ischemic events, and same-day discharge.

A total of 40,278 patients were included in the propensity-matched comparison, of whom 50% received protamine after the LAAO procedure. The use of protamine varied across hospitals, with 88 hospitals (36.2%) using protamine in >75% of cases and 32 hospitals (13.1%) not using protamine at all. Major bleeding occurred less frequently in the protamine group compared with the control group (2.4% vs. 2.8%, p = 0.03). Major vascular complications and pericardial tamponade were rare but slightly higher in the protamine group (0.8% vs. 0.6%, p = 0.04) and (1.0% vs. 0.8%, p = 0.01), respectively. There were no differences in the rates of ischemic or hemorrhagic stroke, all-cause mortality, or the rate of any major adverse event between the two groups. Same-day discharge was more frequent in the protamine group (12.3% vs 9.4%, p ≤ 0.001).

Protamine is used in approximately 50% of LAAO procedures and is associated with lower bleeding events and higher rates of same-day discharge. The higher vascular complication and tamponade is likely due to its ad-hoc use as a reversal agent in these patients.