Factors Associated with Improvement in Utilization of Cardiac Resynchronization Therapy in Eligible Heart Failure Patients: Findings from IMPROVE HF

Variation in hospital use of cardiac resynchronization therapy-defibrillator among eligible patients and association with clinical outcomes

BACKGROUND

Despite strong guideline recommendations for cardiac resynchronization therapy-defibrillator (CRT-D) In select patients, this therapy is underutilized with substantial variation among hospitals, and the association of this variation with outcomes is unknown.

OBJECTIVE

To assess if facility variation in CRT-D utilization is associated with differences in hospital-level outcomes METHODS: We linked Medicare claims data with the NCDR ICD Registry from 2010 to 2015. We assessed the intraclass correlation coefficient to quantify the degree of variation in patient-level CRT usage that can be explained by interfacility variation on a hospital level. To quantify the degree of hospital variation in patient-level outcomes (all-cause mortality, readmissions, and cardiac readmissions) that can be attributed to variations in CRT-D usage, we utilized multi-level modeling.

RESULTS

The study included 30,134 patients across 1,377 hospitals. The median rate of CRT-D implantation among those meeting guideline indications was 89%, but there was a wide variation across hospitals. After adjustment, most of the variation (74%) in hospital rates of CRT-D utilization was attributable to the hospital in which the patient was treated. Differences in hospital CRT-D utilization was associated with 8.76%, 5.26%, and 4.71% of differences in hospital mortality, readmissions, and cardiac readmission rates, respectively (p<0.001 for all outcomes).

CONCLUSIONS

There is wide variation in the use of CRT-D across hospitals that was not explained by case mix. Hospital-level variation in CRT-D utilization was associated with clinically significant differences in outcomes. A measure of CRT-D utilization in eligible patients may serve as a useful metric for quality improvement efforts.

A Population-Based Study of Device Eligibility, Use, and Reasons for Nonimplantation in Patients at Heart Function Clinics

Background

Implantable cardioverter defibrillator (ICD) therapy is lifesaving; however, real-world data regarding the proportion of patients eligible for a primary prevention ICD and subsequent use remain sparse. This study evaluated rates of primary prevention ICD eligibility and use among patients in heart function clinics (HFCs) and to identify reasons for nonimplantation.

Methods

A retrospective study was performed of patients seen at HFCs in Alberta, Canada, from 2013 to 2015. Demographics, comorbidities, clinical indications, and reasons for nonimplantation were abstracted. Eligibility was defined according to the 2008 American College of Cardiology/American Heart Association/Heart Rhythm Society ICD, 2012 American College of Cardiology/American Heart Association/Heart Rhythm Society Focused Update, and 2013 Canadian Cardiovascular Society Cardiac Resynchronization Therapy guidelines. Logistic regression was used to calculate an odds ratio (OR) and 95% confidence interval (CI) for predictors of nonimplantation.

Results

Among 1239 patients in HFCs, the median age was 70 years (interquartile range, 59-80), 67% were male, and the median left ventricular ejection fraction was 0.40 (interquartile range, 0.28-0.53). Overall, 45% of patients (n = 553) met guideline criteria for an ICD, and of those, 36% (n = 198) received a device. Among device nonrecipients, 52% (n = 185) had no documented reason for nonimplantation. The most common reason for nonimplantation among nonrecipients was patient preference (48%). Predictors associated with nonimplantation were age more than 75 years (OR, 1.92; 95% CI, 1.31-2.82) and history of cancer (OR, 2.26; 95% CI, 1.07-4.78). At 3 years follow-up, 27% of nonrecipients were deceased.

Conclusions

We found that one-third of patients who met guideline criteria received an ICD and that documentation for nonimplantation was poor.

More Favorable Response to Cardiac Resynchronization Therapy in Women Than in Men

Background—

Data on sex difference in response to cardiac resynchronization therapy (CRT) remain controversial. We conducted a meta-analysis to summarize all published studies to determine whether sex-based differences in response to CRT exist.

Methods and Results—

We performed a literature search using MEDLINE (source PubMed; January 1966 to March 2014) and EMBASE (January 1980 to March 2014) with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. Seventy-two studies involving 33 434 patients were identified. Overall, female patients had better outcomes from CRT compared with male patients, with a significant 33% reduction in the risk of death from any cause (hazard ratio, 0.67; 95% confidence interval, 0.61–0.74; P <0.001), 20% reduction in death or hospitalization for heart failure (hazard ratio, 0.80; 95% confidence interval, 0.71–0.90; P <0.001), 41% reduction in cardiac death (hazard ratio, 0.59; 95% confidence interval, 0.42–0.84; P <0.001), and 41% reduction in ventricular arrhythmias or sudden cardiac death (hazard ratio, 0.59; 95% confidence interval, 0.49–0.70; P <0.001). These more favorable responses to CRT in women were consistently associated with greater echocardiographic evidence of reverse cardiac remodeling in women than in men.

Conclusions—

Women obtained greater reductions in the risk of death from any cause, cardiac cause, death or hospitalization for heart failure, and ventricular arrhythmias or sudden cardiac death with CRT therapy compared with men, with consistently greater echocardiographic evidence of reverse cardiac remodeling in women than in men. Further studies are needed to investigate the exact reasons for these results and determine whether indications for CRT in women should be different from men.

Rates and reasons for device-based guideline eligibility in patients with heart failure

BACKGROUND

Implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT) are recommended by guidelines for patients with heart failure (HF) meeting specific criteria. Uncertainty exists regarding estimates of device eligibility, related in part to the method of assessing for guideline nonadherence.

OBJECTIVE

The aim of this study was to identify the rates of guideline eligibility and device utilization after accounting for reasons for not receiving an ICD or CRT.

METHODS

Patients were identified from 2006 to 2011 in a tertiary Heart Function Clinic in Canada. The chart-level data were collected that would indicate guideline eligibility and nonadherence.

RESULTS

A total of 762 patients with HF were included (mean age 66 years; 527 (69%) were males; median left ventricular ejection fraction 33%). Over follow-up, 331 patients (43%) were never guideline eligible whereas 431 (57%) were guideline eligible for a device. Yearly rates for ICD and CRT adherence in "guideline-eligible" patients ranged from 59% to 68% and from 66% to 81%, respectively. "Patient preference" was the most commonly documented reason for guideline nonadherence in eligible patients. After removal of patients with reasons for nonadherence, rates of ICD and CRT adherence in the "truly eligible" patients were found to be higher (70%-81% and 71%-88%, respectively) than those in guideline-eligible patients. Independent predictors of device nonadherence in truly eligible patients were age >75 years, QRS duration <120 ms, left ventricular ejection fraction <30%, and female sex.

CONCLUSION

Based on chart-level data, utilization rates of device-based therapies in patients with HF appear much higher than those of prior registry-based estimates. Given the importance of patient preferences for lack of device use, future quality-of-care metrics based on guideline adherence should capture detailed chart-level data and patient preferences.

Similarities and differences in patient characteristics between heart failure registries versus clinical trials

Acute and chronic heart failure results in significant morbidity and mortality to patients and is a major concern for the healthcare systems. Various randomized controlled trials have demonstrated an improvement in morbidity and mortality for patients with heart failure. However, the findings of these trials are often applicable to a limited population. Several large-scale registries are now shedding insight as to the treatment, outcomes, and follow-up of patients in a real-life clinical setting. The objective of this review is to examine some of the heart failure therapies, such as cardiac resynchronization therapy, implantable cardioverter defibrillators and medications, in the context of randomized trials versus clinical registries. This review will also identify how registries are improving patient outcomes and how they are uncovering differences and gaps in treatment in non-randomized trial settings.