Association Between Hospital Volume and 30-Day Readmissions Following Transcatheter Aortic Valve Replacement.

Importance: With the approval of transcatheter aortic valve replacement (TAVR) for patients with severe symptomatic aortic stenosis at intermediate surgical risk, TAVR volume is projected to increase exponentially in the United States. The 30-day readmission rate for TAVR was recently reported at 17.9%. The association between institutional TAVR volume and the 30-day readmission metric has not been examined. Objective: To assess the association between hospital TAVR volume and 30-day readmission. Design, Setting, and Participants: In this observational study, we used the 2014 Nationwide Readmissions Database to identify hospitals with established TAVR programs (performing at least 5 TAVRs in the first quarter of 2014). Based on annual TAVR volume, hospitals were classified as low (<50), medium (≥50 to <100), and high (≥100) volume. Rates, causes, and costs of 30-day readmissions were compared between low-, medium-, and high-volume hospitals. Data were analyzed from November to December 2016. Exposure: Transcatheter aortic valve replacement. Main Outcomes and Measures: Thirty-day readmissions. Results: Of 129 hospitals included in this study, 20 (15.5%) were categorized as low volume, 47 (36.4%) as medium volume, and 62 (48.1%) as high volume. Of 16 252 index TAVR procedures, 663 (4.1%), 3067 (18.9%), and 12 522 (77.0%) were performed at low-, medium-, and high-volume hospitals, respectively. Thirty-day readmission rates were significantly lower in high-volume compared with medium-volume (adjusted odds ratio, 0.76; 95% CI, 0.68-0.85; P < .001) and low-volume (adjusted odds ratio, 0.75; 95% CI, 0.60-0.92; P = .007) hospitals. Noncardiac readmissions were more common in low-volume hospitals (65.6% vs 60.6% in high-volume hospitals), whereas cardiac readmissions were more common in high-volume hospitals (39.4% vs 34.4% in low-volume hospitals). There were no significant differences in length of stay and costs per readmission among the 3 groups (mean [SD], 5.5 [5.0] days vs 5.9 [7.5] days vs 6.0 [5.8] days; P = .74, and $13 886 [18 333] vs $14 135 [17 939] vs $13 432 [15 725]; P = .63, respectively). Conclusions and Relevance: We report for the first time, to our knowledge, an inverse association between hospital TAVR volume and 30-day readmissions. Lower readmission at higher-volume hospitals was associated with significantly lower cost to the health care system.

Thirty-Day Readmissions After Transcatheter Aortic Valve Replacement in the United States: Insights From the Nationwide Readmissions Database.

BACKGROUND: Readmissions after cardiac procedures are common and contribute to increased healthcare utilization and costs. Data on 30-day readmissions after transcatheter aortic valve replacement (TAVR) are limited. METHODS AND RESULTS: Patients undergoing TAVR (International Classification of Diseases-Ninth Revision-CM codes 35.05 and 35.06) between January and November 2013 who survived the index hospitalization were identified in the Nationwide Readmissions Database. Incidence, predictors, causes, and costs of 30-day readmissions were analyzed. Of 12 221 TAVR patients, 2188 (17.9%) were readmitted within 30 days. Length of stay >5 days during index hospitalization (hazard ratio [HR], 1.47; 95% confidence interval [CI], 1.24-1.73), acute kidney injury (HR, 1.23; 95% CI, 1.05-1.44), >4 Elixhauser comorbidities (HR, 1.22; 95% CI, 1.03-1.46), transapical TAVR (HR, 1.21; 95% CI, 1.05-1.39), chronic kidney disease (HR, 1.20; 95% CI, 1.04-1.39), chronic lung disease (HR, 1.16; 95% CI, 1.01-1.34), and discharge to skilled nursing facility (HR, 1.16; 95% CI, 1.01-1.34) were independent predictors of 30-day readmission. Readmissions were because of noncardiac causes in 61.8% of cases and because of cardiac causes in 38.2% of cases. Respiratory (14.7%), infections (12.8%), bleeding (7.6%), and peripheral vascular disease (4.3%) were the most common noncardiac causes, whereas heart failure (22.5%) and arrhythmias (6.6%) were the most common cardiac causes of readmission. Median length of stay and cost of readmissions were 4 days (interquartile range, 2-7 days) and $8302 (interquartile range, $5229-16 021), respectively. CONCLUSIONS: Thirty-day readmissions after TAVR are frequent and are related to baseline comorbidities, TAVR access site, and post-procedure complications. Awareness of these predictors can help identify and target high-risk patients for interventions to reduce readmissions and costs.

Use of bio-informatics assessment schema (BIAS) to improve diagnosis and prognosis of myocardial perfusion data: results from the NHLBI-sponsored women's ischemia syndrome evaluation (WISE).

BACKGROUND: We introduce an algorithmic approach to optimize diagnostic and prognostic value of gated cardiac single photon emission computed tomography (SPECT) and magnetic resonance (MR) myocardial perfusion imaging (MPI) modalities in women with suspected myocardial ischemia. The novel approach: bio-informatics assessment schema (BIAS) forms a mathematical model utilizing MPI data and cardiac metrics generated by one modality to predict the MPI status of another modality. The model identifies cardiac features that either enhance or mask the image-based evidence of ischemia. For each patient, the BIAS model value is used to set an appropriate threshold for the detection of ischemia. METHODS: Women (n=130), with symptoms and signs of suspected myocardial ischemia, underwent MPI assessment for regional perfusion defects using two different modalities: gated SPECT and MR. To determine perfusion status, MR data were evaluated qualitatively (MRIQL) and semi-quantitatively (MRISQ) while SPECT data were evaluated using conventional clinical criteria. Evaluators were masked to results of the alternate modality. These MPI status readings were designated "original". Two regression models designated "BIAS" models were generated to model MPI status obtained with one modality (e.g., MRI) compared with a second modality (e.g., SPECT), but importantly, the BIAS models did not include the primary Original MPI reading of the predicting modality. Instead, the BIAS models included auxiliary measurements like left ventricular chamber volumes and myocardial wall thickness. For each modality, the BIAS model was used to set a progressive threshold for interpretation of MPI status. Women were then followed for 38±14 months for the development of a first major adverse cardiovascular event [MACE: CV death, nonfatal myocardial infarction (MI) or hospitalization for heart failure]. Original and BIAS-augmented perfusion status were compared in their ability to detect coronary artery disease (CAD) and for prediction of MACE. RESULTS: Adverse events occurred in 14 (11%) women and CAD was present in 13 (10%). There was a positive correlation of maximum coronary artery stenosis and BIAS score for MRI and SPECT (P<0.001). Receiver operator characteristic (ROC) analysis was conducted and showed an increase in the area under the curve of the BIAS-augmented MPI interpretation of MACE vs. the original for MRISQ (0.78 vs. 0.54), MRIQL (0.78 vs. 0.64), SPECT (0.82 vs. 0.63) and the average of the three readings (0.80±0.02 vs. 0.60±0.05, P<0.05). CONCLUSIONS: Increasing values of the BIAS score generated by both MRI and SPECT corresponded to the increasing prevalence of CAD and MACE. The BIAS-augmented detection of ischemia better predicted MACE compared with the Original reading for the MPI data for both MRI and SPECT.

Importance of socioeconomic status as a predictor of cardiovascular outcome and costs of care in women with suspected myocardial ischemia. Results from the National Institutes of Health, National Heart, Lung and Blood Institute-sponsored Women's Ischemia Syndrome Evaluation (WISE).

BACKGROUND: For women, who are more likely to live in poverty, defining the clinical and economic impact of socioeconomic factors may aid in defining redistributive policies to improve healthcare quality. METHODS: The NIH-NHLBI-sponsored Women's Ischemia Syndrome Evaluation (WISE) enrolled 819 women referred for clinically indicated coronary angiography. This study's primary end point was to evaluate the independent contribution of socioeconomic factors on the estimation of time to cardiovascular death or myocardial infarction (MI) (n = 79) using Cox proportional hazards models. Secondary aims included an examination of cardiovascular costs and quality of life within socioeconomic subsets of women. RESULTS: In univariable models, socioeconomic factors associated with an elevated risk of cardiovascular death or MI included an annual household income <$20,000 (p = 0.0001), <9th grade education (p = 0.002), being African American, Hispanic, Asian, or American Indian (p = 0.016), on Medicaid, Medicare, or other public health insurance (p < 0.0001), unmarried (p = 0.001), unemployed or employed part-time (p < 0.0001), and working in a service job (p = 0.003). Of these socioeconomic factors, income (p = 0.006) remained a significant predictor of cardiovascular death or MI in risk-adjusted models that controlled for angiographic coronary disease, chest pain symptoms, and cardiac risk factors. Low-income women, with an annual household income <$20,000, were more often uninsured or on public insurance (p < 0.0001) yet had the highest 5-year hospitalization and drug treatment costs (p < 0.0001). Only 17% of low-income women had prescription drug coverage (vs. >or=50% of higher-income households, p < 0.0001), and 64% required >or=2 anti-ischemic medications during follow-up (compared with 45% of those earning >or=$50,000, p < 0.0001). CONCLUSIONS: Economic disadvantage prominently affects cardiovascular disease outcomes for women with chest pain symptoms. These results further support a profound intertwining between poverty and poor health. Cardiovascular disease management strategies should focus on policies that track unmet healthcare needs and worsening clinical status for low-income women.

The economic burden of angina in women with suspected ischemic heart disease: results from the National Institutes of Health--National Heart, Lung, and Blood Institute--sponsored Women's Ischemia Syndrome Evaluation.

BACKGROUND: Coronary angiography is one of the most frequently performed procedures in women; however, nonobstructive (ie, < 50% stenosis) coronary artery disease (CAD) is frequently reported. Few data exist regarding the type and intensity of resource consumption in women with chest pain after coronary angiography. METHODS AND RESULTS: A total of 883 women referred for coronary angiography were prospectively enrolled in the National Institutes of Health--National Heart, Lung, and Blood Institute--sponsored Women's Ischemia Syndrome Evaluation (WISE). Cardiovascular prognosis and cost data were collected. Direct (hospitalizations, office visits, procedures, and drug utilization) and indirect (out-of-pocket, lost productivity, and travel) costs were estimated through 5 years of follow-up. Among 883 women, 62%, 17%, 11%, and 10% had nonobstructive and 1-vessel, 2-vessel, and 3-vessel CAD, respectively. Five-year cardiovascular death or myocardial infarction rates ranged from 4% to 38% for women with nonobstructive to 3-vessel CAD (P < 0.0001). Five-year rates of hospitalization for chest pain occurred in 20% of women with nonobstructive CAD, increasing to 38% to 55% for women with 1-vessel to 3-vessel CAD (P < 0.0001). The volume of repeat catheterizations or angina hospitalizations was 1.8-fold higher in women with nonobstructive versus 1-vessel CAD after 1 year of follow-up (P < 0.0001). Drug treatment was highest for those with nonobstructive or 1-vessel CAD (P < 0.0001). The proportion of costs for anti-ischemic therapy was higher for women with nonobstructive CAD (15% versus 12% for 1-vessel to 3-vessel CAD; P = 0.001). For women with nonobstructive CAD, average lifetime cost estimates were $767,288 (95% CI, $708,480 to $826,097) and ranged from $1,001,493 to $1,051,302 for women with 1-vessel to 3-vessel CAD (P = 0.0003). CONCLUSIONS: Symptom-driven care is costly even for women with nonobstructive CAD. Our lifetime estimates for costs of cardiovascular care identify a significant subset of women who are unaccounted for within current estimates of the economic burden of coronary heart disease.

Prognosis in women with myocardial ischemia in the absence of obstructive coronary disease: results from the National Institutes of Health-National Heart, Lung, and Blood Institute-Sponsored Women's Ischemia Syndrome Evaluation (WISE).

BACKGROUND: We previously reported that 20% of women with chest pain but without obstructive coronary artery disease (CAD) had stress-induced reduction in myocardial phosphocreatine-adenosine triphosphate ratio by phosphorus-31 nuclear magnetic resonance spectroscopy (abnormal MRS), consistent with myocardial ischemia. The prognostic implications of these findings are unknown. METHODS AND RESULTS: Women referred for coronary angiography for suspected myocardial ischemia underwent MRS handgrip stress testing and follow-up evaluation. These included (1) n=60 with no CAD/normal MRS, (2) n=14 with no CAD/abnormal MRS, and (3) n=352 a reference group with CAD. Cardiovascular events were death, myocardial infarction, heart failure, stroke, other vascular events, and hospitalization for unstable angina. Cumulative freedom from events at 3 years was 87%, 57%, and 52% for women with no CAD/normal MRS, no CAD/abnormal MRS, and CAD, respectively (P<0.01). After adjusting for CAD and cardiac risk factors, a phosphocreatine-adenosine triphosphate ratio decrease of 1% increased the risk of a cardiovascular event by 4% (P=0.02). The higher event rate in women with no CAD/abnormal MRS was primarily due to hospitalization for unstable angina, which is associated with repeat catheterization and higher healthcare costs. CONCLUSIONS: Among women without CAD, abnormal MRS consistent with myocardial ischemia predicted cardiovascular outcome, notably higher rates of anginal hospitalization, repeat catheterization, and greater treatment costs. Further evaluation into the underlying pathophysiology and possible treatment options for women with evidence of myocardial ischemia but without CAD is indicated.