Factors associated with improvement in guideline-based use of ICDs in eligible heart failure patients

Background: IMPROVE HF, a 24-month performance improvement initiative for outpatient cardiology and multispecialty practices, demonstrated significant improvement in guideline-based use of implantable cardioverter-defibrillators (ICDs) for patients with heart failure (HF). We investigated patient, physician, and practice factors associated with improvements in ICD use. Methods: Patients with HF or postmyocardial infarction (MI) left ventricular systolic dysfunction who met eligibility criteria for ICDs at baseline and 24 months were analyzed. Multivariate analyses were performed to identify patient, physician, and practice characteristics associated with greater improvement in ICD therapy rates from baseline to 24 months. Results: There were 4,058 patients eligible for ICD therapy at baseline and 24 months, with 2,600 (64.1%) treated at baseline and 3,361 (82.8%) treated at 24 months (+18.7%, P < 0.001). Practice heterogeneity in ICD use was significantly decreased after implementation of the performance improvement initiative. Characteristics independently associated with improvement in use of ICD therapy included race, history of MI, presence of edema, QRS duration, months since last measured left ventricular ejection fraction, and number of physicians in the practice. Improvement in ICD use was independent of other patient, physician, and practice characteristics, including age and sex. Conclusions: The IMPROVE HF performance improvement initiative was associated with substantially improved adherence to guideline-recommended ICD therapy. Certain patient and practice characteristics, including race, history of MI, edema, QRS duration, and number of physicians in the practice, were independently associated with improvement in ICD use. These findings highlight the need for ongoing quality improvement monitoring and performance improvement activities.