Abstract 49: Variation In Cardiac Rehabilitation Enrollment During Aortic Valve Replacement Episodes Of Care

Intro: Despite providing benefit in the setting of aortic valve replacement (AVR), cardiac rehabilitation (CR) utilization remains low, with few studies evaluating hospital and patient-level variation in CR enrollment. We explored determinants of CR variability during AVR episodes of care: transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR).

Methods/Results: A cohort of 10,124 AVR episodes of care (TAVR n=5,121 from 24 hospitals; SAVR n=5,003 from 32 hospitals) were identified from the Michigan Value Collaborative statewide multipayer registry (2015 to 2019). CR enrollment was defined as the presence of a professional or facility claim (93797, 93798, G0422, G0423) within 90 days of discharge. Annual trends in CR were evaluated for TAVR, SAVR, and all AVR. CR use in SAVR was significantly higher than TAVR and increased over time for all modalities (p<0.001, Figure 1). Multilevel logistic regression analysis identified significant differences in CR enrollment across age groups, comorbidities, and payer status. At the hospital-level, CR enrollment rates for all AVR varied 10-fold (4.8% to 68.7%) and moderately correlated between SAVR and TAVR (Pearson r=0.56, p<0.01, Figure 2).

Conclusions: Substantial variation exists in CR enrollment during AVR episodes of care across hospitals. However, within-hospital CR enrollment rates were significantly correlated across treatment strategies. These findings suggest that CR enrollment is the product of hospital-specific practice patterns. Identifying hospital practices associated with higher CR enrollment can help assist future quality improvement efforts to increase CR use after AVR.

Abstract 29: Evaluating The Feasibility Of A Statewide Collaboration To Improve Cardiac Rehabilitation Participation: The Michigan Cardiac Rehabilitation Consortium

Background: Regional quality improvement collaboratives may provide one solution to improving cardiac rehabilitation (CR) participation through performance benchmarking and provider engagement. The objective of this descriptive study was to evaluate the feasibility of the Michigan Cardiac Rehab Consortium to improve CR participation

Methods and Results: Multipayer claims data from the Michigan Value Collaborative were used to identify hospitals and CR facilities. Univariate analyses described participating hospital characteristics and hospital-level rates of CR enrollment within 1-year. A total of 95 hospitals and 85 CR facilities with 48 hospitals (51%) providing interventional cardiology services and 33 (35%) provided cardiac surgical services. The overall consortium-wide enrollment rate into CR across all conditions was 19.8% (26,398 of 133,641 eligible admissions), which was highest for CABG (58.4%), followed by SAVR (54.8%), PCI (34.6%), TAVR (33.1%), AMI (12.7%), and CHF (3.4%). There was wide variation in CR participation across participating eligible admissions and hospitals (Figure). A 17-member multidisciplinary stakeholder group was assembled representing 12 institutions and diverse roles, including exercise physiologists, cardiologist, program directors, and patients. Three diverse CR facilities participated in virtual site visits, which revealed individual successes in improving CR participation, but a variety of barriers to participation related to referrals, capacity and staffing constraints, and geographic and financial barriers.

Conclusions: This study demonstrated the feasibility of a statewide collaboration centered around the goal of equitably improving CR enrollment for all eligible patients that is supported by a multidisciplinary stakeholder group and performance benchmarking. Future work will seek to continuously improve and evaluate the impact of this consortium on CR participation in Michigan.

Hospital and Operator Variation in Cardiac Rehabilitation Referral and Participation After Percutaneous Coronary Intervention: Insights From Blue Cross Blue Shield of Michigan Cardiovascular Consortium

BACKGROUND

Despite its established benefit and strong endorsement in international guidelines, cardiac rehabilitation (CR) use remains low. Identifying determinants of CR referral and use may help develop targeted policies and quality improvement efforts. We evaluated the variation in CR referral and use across percutaneous coronary intervention (PCI) hospitals and operators.

METHODS

We performed a retrospective observational cohort study of all patients who underwent PCI at 48 nonfederal Michigan hospitals between January 1, 2012 and March 31, 2018 and who had their PCI clinical registry record linked to administrative claims data. The primary outcomes included in-hospital CR referral and CR participation, defined as at least one outpatient CR visit within 90 days of discharge. Bayesian hierarchical regression models were fit to evaluate the association between PCI hospital and operator with CR referral and use after adjusting for patient characteristics.

RESULTS

Among 54 217 patients who underwent PCI, 76.3% received an in-hospital referral for CR, and 27.1% attended CR within 90 days after discharge. There was significant hospital and operator level variation in in-hospital CR referral with median odds ratios of 3.88 (95% credible interval [CI], 3.06-5.42) and 1.64 (95% CI, 1.55-1.75), respectively, and in CR participation with median odds ratios of 1.83 (95% CI, 1.63-2.15) and 1.40 (95% CI, 1.35-1.47), respectively. In-hospital CR referral was significantly associated with an increased likelihood of CR participation (adjusted odds ratio, 1.75 [95% CI, 1.52-2.01]), and this association varied by treating PCI hospital (odds ratio range, 0.92-3.75) and operator (odds ratio range, 1.26-2.82).

CONCLUSIONS

In-hospital CR referral and 90-day CR use after PCI varied significantly by hospital and operator. The association of in-hospital CR referral with downstream CR use also varied across hospitals and less so across operators suggesting that specific hospitals and operators may more effectively translate CR referrals into downstream use. Understanding the factors that explain this variation will be critical to developing strategies to improve CR participation overall.

Percutaneous Coronary Intervention in Patients With a History of Gastrointestinal Bleeding (From the Blue Cross Blue Shield of Michigan Cardiovascular Consortium)

Potent antithrombotic agents are routinely prescribed after percutaneous coronary intervention (PCI) to reduce ischemic complications. However, in patients who are at an increased bleeding risk, this may pose significant risks. We sought to evaluate the association between a history of gastrointestinal bleeding (GIB) and outcomes after PCI. We linked clinical registry data from PCIs performed at 48 Michigan hospitals between 1/2013 and 3/2018 to Medicare claims. We used 1:5 propensity score matching to adjust for patient characteristics. In-hospital outcomes included bleeding, transfusion, stroke or death. Post-discharge outcomes included 90-day all-cause readmission and long-term mortality. Of 30,206 patients, 1.1% had a history of GIB. Patients with a history of GIB were more likely to be older, female, and have more cardiovascular comorbidities. After matching, those with a history of GIB (n = 312) had increased post-procedural transfusions (15.7% vs 8.4%; p < 0.001), bleeding (11.9% vs 5.2%; p < 0.001), and major bleeding (2.8% vs 0.6%; p = 0.004). Ninety-day readmission rates were similar among those with and without a history of GIB (34.3% vs 31.3%; p = 0.318). There was no significant difference in post-discharge survival (1 year: 78% vs 80%; p = 0.217; 5 years: 54% vs 51%; p = 0.189). In conclusion, after adjusting for baseline characteristics, patients with a history of GIB had increased risk of post-PCI in-hospital bleeding complications. However, a history of GIB was not significantly associated with 90-day readmission or long-term survival.