Methods. Data from women fitted with WCD from 2015 to 2018 were obtained from the manufacturer’s database. Quartiles of HR were compared between patients showing improvement of EF and patients who either had indication for implantable cardioverter defibrillators (ICD) or died.
Results. A total of 15 321 women with mean age of 66 ± 13 years were included. Mean time of WCD use was 96 ± 50 days. Patients with improvement of EF had significantly lower HR compared to patients who died or received an ICD. Univariable logistic regression showed that lower HR was predictive for improvement, with nighttime HR at follow up showing strongest predictive power with OR of 2.06 (95%CI 1.90-2.23, p<0.001). Multivariable adjustment revealed that daytime, nighttime and delta nighttime HR at the end of WCD use was predictive for improvement.
Conclusion. HR was significantly lower in patients showing improvement of EF. Absolute daytime, nighttime and delta nighttime HR at follow up showed predictive ability for recovery.