Abstract 18973: Left Ventricular Function Improvement After Recent MI in Patients Using a Wearable Cardioverter Defibrillator
Introduction: The wearable cardioverter defibrillator (WCD) has been used to protect AMI patients with reduced LVEF (≤35%) until ICD evaluation is recommended. The rate of EF improvement (e.g. EF>35%) over the initial 8-12 weeks after AMI has not been reported.
METHODS: The manufacturer-maintained registry was searched for AMI patients who received a WCD shock for VT/VF between 05/2008 and 02/2013. The treated group was matched (1: ~4) with event-free WCD patients by ICD-9 code (410.*), gender, age and prescription date. Chart notes were reviewed for clinical characteristics. Follow-up was assessed through the registry and Social Security Death Master File.
RESULTS: There were 992 (age=63±12, female=20.2%) AMI patients included in the final analysis, 206 treated by WCD and 786 event-free patients. Median follow-up was 334 days. Mean length of WCD use was 67±506 (median=38) days. Subgroup clinical characteristics are presented in Table 1. In the event-free group, 289 (38.9%) patients showed EF improvement to >35%. Nine (4.5%) in the treated group continued wearing the WCD until EF recovery, while 125 (60.7%) received ICD. Absence of recorded heart failure and/or diabetes were associated with LVEF recovery (p<.0001).
CONCLUSION: In our study, almost 40% of AMI patients with initial EF ≤35% had EF improvement in two months. The EF recovery group had lower rates of heart failure and diabetes. WCD allows time for left ventricular function recovery in low EF post MI patients, optimizing ICD implantation decisions.
Author Disclosures: C. Wan: Employment; Significant; ZOLL. S.J. Szymkiewicz: Employment; Significant; ZOLL.
- © 2014 by American Heart Association, Inc.