Impact of annual operator and institutional volume on percutaneous coronary intervention outcomes: a 5-year United States experience (2005-2009)

Center Volumes Correlate with Likelihood of Stent Implantation in German Coronary Angiography

Aims

Literature on percutaneous coronary intervention (PCI) stated an inverse relationship between hospital volume and mortality, but the effects on other characteristics are unclear.

Methods

Using German national records, all coronary angiographies with coronary artery disease in 2017 were identified. We applied risk-adjustment to account for differences in population characteristics.

Results

Of overall 528,188 patients, 55.22% received at least one stent, with on average 1.01 stents implanted in all patients. Based on those patients who received at least one stent, this corresponds to an average number of 1.82 stents. In-hospital mortality across all patients was 2.93%, length of hospital stay was 6.46 days, and mean reimbursement was €5,531. There were comparatively more emergency admissions in low volume centers and more complex cases (3-vessel disease, left main stenosis, and in-stent stenosis) in high volume centers. In multivariable regression analysis, volume and likelihood of stent implantation (p=0.003) as well as number of stents (p=0.020) were positively correlated. No relationship was seen for in-hospital mortality (p=0.105), length of stay (p=0.201), and reimbursement (p=0.108). Nonlinear influence of volume suggests a ceiling effect: In hospitals with ≤100 interventions, likelihood and number of implanted stents are lowest (∼34% and 0.6). After that, both rise steadily until a volume of 500 interventions. Finally, both remain stable in the categories of over 500 interventions (∼60% and 1.1).

Conclusion

In PCI, lower volume centers contribute to emergency care. Higher volume centers treat more complex cases and show a higher likelihood of stent implantations, with a stable safety.

Transradial intervention in dialysis patients undergoing percutaneous coronary intervention: a Japanese nationwide registry study

Aims

Transradial intervention (TRI) for percutaneous coronary intervention (PCI) is used to reduce periprocedural complications. However, its effectiveness and safety for patients on dialysis are not well established. We aimed to investigate the association of TRI with in-hospital complications in dialysis patients undergoing PCI.

Methods and results

We included 44 462 patients on dialysis who underwent PCI using Japanese nationwide PCI registry data (2019-21) regardless of acute or chronic coronary syndrome. Patients were categorized based on access site: TRI, transfemoral intervention (TFI). Periprocedural access site bleeding complication requiring transfusion was the primary outcome and in-hospital death, and other periprocedural complications were the secondary outcomes. Matched weighted analysis was performed for TRI and TFI. Here, 8267 (18.6%) underwent TRI, and 36 195 (81.4%) underwent TFI. Patients who received TRI were older and had lower rates of comorbidities than those who received TFI. Access site bleeding rate and in-hospital death were significantly lower in the TRI group (0.1% vs. 0.7%, P < 0.001; 1.8% vs. 3.2%, P < 0.001, respectively). After adjustment, TRI was associated with a lower risk of access site bleeding (odds ratio [OR] [95% confidence interval (CI)]: 0.19 [0.099-0.38]; P < 0.001) and in-hospital death (OR [95% CI]: 0.79 [0.65-0.96]; P = 0.02). Other periprocedural complications between TRI and TFI were not significantly different.

Conclusion

In patients undergoing dialysis and PCI, TRI had a lower risk of access site bleeding and in-hospital death than TFI. This suggests that TRI may be safer for this patient population.

Volume-outcome relationship in complication-related mortality after percutaneous coronary interventions: an analysis on the failure-to-rescue rate in the Japanese Nationwide Registry

In-hospital mortality following percutaneous coronary intervention (PCI) varies across institutions with different annual PCI volumes. The failure to rescue (FTR) rate, defined as the mortality rate following PCI-related complications, may account for the volume-outcome relationship. The Japanese Nationwide PCI Registry, a consecutive, nationally mandated registry between 2019 and 2020, was queried. The FTR rate is defined as 'the number of patients who died following PCI-related complications' divided by 'the number of patients who experienced at least one PCI-related complication.' Multivariate analysis was used to calculate the risk-adjusted odds ratio (aOR) of the FTR rates among hospitals stratified into tertiles as low (≤ 236/year), medium (237-405/year), and high (≥ 406/year). A total of 465,716 PCIs and 1007 institutions were included. A volume-outcome relationship was observed for in-hospital mortality, and the medium-volume (aOR 0.90, 95% confidence interval [CI] 0.85-0.96), as well as high-volume (aOR 0.84, 95% CI 0.79-0.89) hospitals, had significantly lower in-hospital mortality than low-volume hospitals. Complication rates were lower at high-volume centers (1.9%, 2.2%, and 2.6% for high-, medium-, and low-volume centers, respectively; p < 0.001). The overall FTR rate was 19.0%. The FTR rates for the low-, medium-, and high-volume hospitals were 19.3%, 17.7%, and 20.6%, respectively. The medium-volume hospitals had a lower FTR rate (aOR 0.82, 95% [CI] 0.68-0.99), whereas the FTR rate was similar at the high-volume hospitals compared with that of the low-volume hospitals (aOR 1.02, 95% CI 0.83-1.26). In-hospital mortality was low after PCI in high-volume hospitals. However, the FTR rate in high-volume hospitals was not necessarily lower than that in low-volume hospitals. The FTR rate did not account for the volume-outcome relationship in PCI.

Revascularization and Left Ventricular Dysfunction for ICD Eligibility

Common triggers for sudden cardiac death (SCD) are transient ischemia, hemodynamic fluctuations, neurocardiovascular influences, and environmental factors. SCD occurs rapidly when sinus rhythm degenerates into ventricular tachycardia (VT) and/or ventricular fibrillation (VF), followed by asystole. Such progressive worsening of the cardiac rhythm is in most cases observed in the setting of ischemic heart disease and often associated with advanced left ventricular (LV) impairment. Revascularization prevents negative outcomes including SCD and heart failure (HF) due to LV dysfunction (LVD). The implantable cardioverter-defibrillator (ICD) on top of medical therapy is superior to antiarrhythmic drugs for patients with LVD and VT/VF. The beneficial effects of ICD have been demonstrated in primary prevention of SCD as well. However, yet debated is the temporal management for patients with LVD who are eligible to ICD prior to revascularization, either through percutaneous or surgical approach. Restoration of coronary blood flow has a dramatic impact on adverse LV remodeling, while it requires aggressive long-term antiplatelet therapy, which might increase complication for eventual ICD procedure when percutaneous strategy is pursued; on the other hand, when LV and/or multiorgan dysfunction is present and coronary artery bypass grafting is chosen, the overall risk is augmented, mostly in HF patients. The aims of this review are to describe the pathophysiologic benefits of revascularization, the studies addressing percutaneous, surgical or no revascularization and ICD implantation, as well as emerging defibrillation strategies for patients deemed at transient risk of SCD and/or at higher risk for transvenous ICD implantation.

Race-Based Differences in ST-Segment-Elevation Myocardial Infarction Process Metrics and Mortality From 2015 Through 2021: An Analysis of 178 062 Patients From the American Heart Association Get With The Guidelines-Coronary Artery Disease Registry

BACKGROUND

Systems of care have been developed across the United States to standardize care processes and improve outcomes in patients with ST-segment-elevation myocardial infarction (STEMI). The effect of contemporary STEMI systems of care on racial and ethnic disparities in achievement of time-to-treatment goals and mortality in STEMI is uncertain.

METHODS

We analyzed 178 062 patients with STEMI (52 293 women and 125 769 men) enrolled in the American Heart Association Get With The Guidelines-Coronary Artery Disease registry between January 1, 2015, and December 31, 2021. Patients were stratified into and outcomes compared among 3 racial and ethnic groups: non-Hispanic White, Hispanic White, and Black. The primary outcomes were the proportions of patients achieving the following STEMI process metrics: prehospital ECG obtained by emergency medical services; hospital arrival to ECG obtained within 10 minutes for patients not transported by emergency medical services; arrival-to-percutaneous coronary intervention time within 90 minutes; and first medical contact-to-device time within 90 minutes. A secondary outcome was in-hospital mortality. Analyses were performed separately in women and men, and all outcomes were adjusted for age, comorbidities, acuity of presentation, insurance status, and socioeconomic status measured by social vulnerability index based on patients' county of residence.

RESULTS

Compared with non-Hispanic White patients with STEMI, Hispanic White patients and Black patients had lower odds of receiving a prehospital ECG and achieving targets for door-to-ECG, door-to-device, and first medical contact-to-device times. These racial disparities in treatment goals were observed in both women and men, and persisted in most cases after multivariable adjustment. Compared with non-Hispanic White women, Hispanic White women had higher adjusted in-hospital mortality (odds ratio, 1.39 [95% CI, 1.12-1.72]), whereas Black women did not (odds ratio, 0.88 [95% CI, 0.74-1.03]). Compared with non-Hispanic White men, adjusted in-hospital mortality was similar in Hispanic White men (odds ratio, 0.99 [95% CI, 0.82-1.18]) and Black men (odds ratio, 0.96 [95% CI, 0.85-1.09]).

CONCLUSIONS

Race- or ethnicity-based disparities persist in STEMI process metrics in both women and men, and mortality differences are observed in Hispanic White compared with non-Hispanic White women. Further research is essential to evolve systems of care to mitigate racial differences in STEMI outcomes.

Association between Case Volumes of Extracorporeal Life Support and Clinical Outcome in Out-of-Hospital Cardiac Arrest

AIM

Extracorporeal life support (ECLS) for out-of-hospital cardiac arrest (OHCA) is increasing. There is little evidence identifying the association between hospital ECLS case volumes and outcomes in different populations receiving ECLS or conventional cardiopulmonary resuscitation (CPR). The goal of this investigation was to identify the association between ECLS case volumes and clinical outcomes of OHCA patients.

METHODS

This cross-sectional observational study used the National OHCA Registry for adult OHCA cases in Seoul, Korea between January 2015 and December 2019. If the ECLS volume during the study period was >20, the institution was defined as a high-volume ECLS center. Others were defined as low-volume ECLS centers. Outcomes were good neurologic recovery (cerebral performance category 1 or 2) and survival to discharge. We performed multivariate logistic regression and interaction analyses to assess the association between case volume and clinical outcome.

RESULTS

Of the 17,248 OHCA cases, 3,731 were transported to high-volume centers. Among the patients who underwent ECLS, those at high-volume centers had a higher neurologic recovery rate than those at low-volume centers (17.0% vs. 12.0%), and the adjusted OR for good neurologic recovery was 2.22 (95% confidence interval (CI): 1.15-4.28) in high-volume centers compared to low-volume centers. For patients who received conventional CPR, high-volume centers also showed higher survival-to-discharge rates (adjusted OR of 1.16, 95%CI: 1.01-1.34).

CONCLUSIONS

High-volume ECLS centers showed better neurological recovery in patients who underwent ECLS. High-volume centers also had better survival-to-discharge rates than low-volume centers for patients not receiving ECLS.

Interfacility Transfer of Uninsured vs Insured Patients With ST-Segment Elevation Myocardial Infarction in California

Importance

Insurance status has been associated with whether patients with ST-segment elevation myocardial infarction (STEMI) presenting to emergency departments are transferred to other facilities, but whether the facility's percutaneous coronary intervention capabilities mediate this association is unknown.

Objective

To examine whether uninsured patients with STEMI were more likely than patients with insurance to experience interfacility transfer.

Design, Setting, and Participants

This observational cohort study compared patients with STEMI with and without insurance who presented to California emergency departments between January 1, 2010, and December 31, 2019, using the Patient Discharge Database and Emergency Department Discharge Database from the California Department of Health Care Access and Information. Statistical analyses were completed in April 2023.

Exposures

Primary exposures were lack of insurance and facility percutaneous coronary intervention capabilities.

Main Outcomes and Measures

The primary outcome was transfer status from the presenting emergency department of a percutaneous coronary intervention-capable hospital, defined as a facility performing 36 percutaneous coronary interventions per year. Multivariable logistic regression models with multiple robustness checks were performed to determine the association of insurance status with the odds of transfer.

Results

This study included 135 358 patients with STEMI, of whom 32 841 patients (24.2%) were transferred (mean [SD] age, 64 [14] years; 10 100 women [30.8%]; 2542 Asian individuals [7.7%]; 2053 Black individuals [6.3%]; 8285 Hispanic individuals [25.2%]; 18 650 White individuals [56.8%]). After adjusting for time trends, patient factors, and transferring hospital characteristics (including percutaneous coronary intervention capabilities), patients who were uninsured had lower odds of experiencing interfacility transfer than those with insurance (adjusted odds ratio, 0.93; 95% CI, 0.88-0.98; P = .01).

Conclusions and Relevance

After accounting for a facility's percutaneous coronary intervention capabilities, lack of insurance was associated with lower odds of emergency department transfer for patients with STEMI. These findings warrant further investigation to understand the characteristics of facilities and outcomes for uninsured patients with STEMI.

Do PCI Facility Openings and Closures Affect AMI Outcomes Differently in High- vs Average-Capacity Markets?

BACKGROUND

Disparities in access to percutaneous coronary intervention (PCI) for patients with acute myocardial infarction may result from openings and closures of PCI-providing hospitals, potentially leading to low hospital PCI volume, which is associated with poor outcomes.

OBJECTIVES

The authors sought to determine whether openings and closures of PCI hospitals have differentially impacted patient health outcomes in high- vs average-capacity PCI markets.

METHODS

In this retrospective cohort study, the authors identified PCI hospital availability within a 15-minute driving time of zip code communities. The authors categorized communities by baseline PCI capacity and identified changes in outcomes associated with PCI-providing hospital openings and closures using community fixed-effects regression models.

RESULTS

From 2006 to 2017, 20% and 16% of patients in average- and high-capacity markets, respectively, experienced a PCI hospital opening within a 15-minute drive. In average-capacity markets, openings were associated with a 2.6 percentage point decrease in admission to a high-volume PCI facility; high-capacity markets saw an 11.6 percentage point decrease. After an opening, patients in average-capacity markets experienced a 5.5% and 7.6% relative increase in likelihood of same-day and in-hospital revascularization, respectively, as well as a 2.5% decrease in mortality. PCI hospital closures were associated with a 10.4% relative increase in admission to high-volume PCI hospitals and a 1.4 percentage point decrease in receipt of same-day PCI. There was no change observed in high-capacity PCI markets.

CONCLUSIONS

After openings, patients in average-capacity markets derived significant benefits, whereas those in high-capacity markets did not. This suggests that past a certain threshold, facility opening does not improve access and health outcomes.

Institutional Volume and Initial Results for Endovascular Treatment for Chronic Occlusive Lower-Extremity Artery Disease: A Report From the Japanese Nationwide Registry

PURPOSE

Chronic total occlusion (CTO) remains as a major target for endovascular treatment (EVT) in improving symptomatic lower-extremity artery disease (LEAD). However, despite the technical demand and learning curve for the procedure, volume-outcome relationship of EVT targeted for CTO in symptomatic LEAD remains unclear.

MATERIALS AND METHODS

Data were obtained from a nationwide registry for EVT procedures limited to the Japanese Association of Cardiovascular Intervention and Therapeutics between January 2018 and December 2020 from 660 cardiovascular centers in Japan. In total, 96 099 patients underwent EVT for symptomatic LEAD, and 41 900 (43.6%) underwent CTO-targeted EVTs during the study period. Institutional volume was classified into quartiles. The association of institutional volumes with short-term outcomes was explored using the generalized linear mixed model using a logit link function, in which, interinstitution variability was used as a random effect.

RESULTS

The median institutional volume for all EVT cases per quartile was 29, 68, 125, and 299 cases/year for the first, second, third, and fourth quartiles, respectively. With each model analysis, the adjusted odds ratios (ORs) for technical success were significantly lower in patients who underwent EVT in institutions within the first quartile (<52 cases/year) than in the other quartiles (P < .01, respectively). On the contrary, the adjusted ORs for procedural complications were significantly higher in the first and second quartiles than in the third and fourth quartiles (P < .01, respectively).

CONCLUSION

In contemporary Japanese EVT practice, a higher institutional volume but not operator volume was associated with a higher technical success rate and a lower procedural complication rate in patients with symptomatic LEAD involving CTO lesions.

CLINICAL IMPACT

EVT for CTO lesions is still challenging for clinicians because of difficulties of wire/devise crossing or high procedural complications rate. Our study demonstrated that a higher institutional volume but not operator volume was associated with a higher technical success rate and a lower procedural complication rate in patients with symptomatic LEAD involving CTO lesions. In contemporary Japanese practice, a higher institutional experience has better impacts on short-term clinical outcomes. Future research should determine the relationship between institutional volume and long-term clinical outcomes.

Influence of the interventionist's experience on outcomes of endovascular thrombectomy in acute ischemic stroke: results from the MR CLEAN Registry

BACKGROUND

The relationship between the interventionist's experience and outcomes of endovascular thrombectomy (EVT) for acute ischemic stroke of the anterior circulation, is unclear.

OBJECTIVE

To assess the effect of the interventionist's level of experience on clinical, imaging, and workflow outcomes. Secondly, to determine which of the three experience definitions is most strongly associated with these outcome measures.

METHODS

We analysed data from 2700 patients, included in the MR CLEAN Registry. We defined interventionist's experience as the number of procedures performed in the year preceding the intervention (EXPfreq), total number of procedures performed (EXPno), and years of experience (EXPyears). Our outcomes were the baseline-adjusted National Institutes of Health Stroke Scale (NIHSS) score at 24-48 hours post-EVT, recanalization (extended Thrombolysis in Cerebral Infarction (eTICI) score ≥2B), and procedural duration. We used multilevel regression models with interventionists as random intercept. For EXPfreq and EXPno results were expressed per 10 procedures.

RESULTS

Increased EXPfreq was associated with lower 24-48 hour NIHSS scores (adjusted (a)β:-0.46, 95% CI -0.70 to -0.21). EXPno and EXPyears were not associated with short-term neurological outcomes. Increased EXPfreq and EXPno were both associated with recanalization (aOR=1.20, 95% CI 1.11 to 1.31 and aOR=1.08, 95% CI 1.04 to 1.12, respectively), and increased EXPfreq, EXPno, and EXPyears were all associated with shorter procedure times (aβ:-3.08, 95% CI-4.32 to -1.84; aβ:-1.34, 95% CI-1.84 to -0.85; and aβ:-0.79, 95% CI-1.45 to -0.13, respectively).

CONCLUSIONS

Higher levels of interventionist's experience are associated with better outcomes after EVT, in particular when experience is defined as the number of patients treated in the preceding year. Every 20 procedures more per year is associated with approximately one NIHSS score point decrease, an increased probability for recanalization (aOR=1.44), and a 6-minute shorter procedure time.

No "July Effect" in the management and outcomes of acute myocardial infarction: An 18-year United States national study

BACKGROUND

There has been conflicting reports on the effect of new trainees on clinical outcomes at teaching hospitals in the first training month (July in the United States of America). We sought to assess this "July effect" in a contemporary acute myocardial infarction (AMI) population.

METHODS

Adult (>18 years) AMI hospitalizations in May and July in urban teaching and urban nonteaching hospitals in the United States were identified from the HCUP-NIS database (2000-2017). In-hospital mortality was compared between May and July admissions. A difference-in-difference analysis comparing a change in outcome from May to July in teaching hospitals to a change in outcome from May to July in nonteaching hospitals was also performed.

RESULTS

A total of 1,312,006 AMI hospitalizations from urban teaching (n = 710,593; 54.2%) or nonteaching (n = 601,413; 45.8%) hospitals in the months of May and July were evaluated. May admissions in teaching hospitals, had greater comorbidity, higher rates of acute multiorgan failure (10.6% vs. 10.2%, p < 0.001) and lower rates of cardiac arrest when compared to July admissions. July AMI admissions had lower in-hospital mortality compared to May (5.6% vs. 5.8%; adjusted odds ratio 0.94 [95% confidence interval 0.92-0.97]; p < 0.001) in teaching hospitals. Using the difference-in-difference model, there was no evidence of a July effect for in-hospital mortality (p = 0.19).

CONCLUSIONS

There was no July effect for in-hospital mortality in this contemporary AMI population.

The Intersection Between Heart Failure and Critical Care Cardiology: An International Perspective on Structure, Staffing, and Design Considerations

The overall patient population in contemporary cardiac intensive care units (CICUs) has only increased with respect to patient acuity, complexity, and illness severity. The current population has more cardiac and noncardiac comorbidities, a higher prevalence of multiorgan injury, and consumes more critical care resources than previously. Patients with heart failure (HF) now occupy a large portion of contemporary tertiary or quaternary care CICU beds around the world. In this review, we discuss the core issues that relate to the care of critically ill patients with HF, including global perspectives on the organization, designation, and collaboration of CICUs regionally and across institutions, as well as unique models for provisioning care for patients with HF within a health care setting. The latter includes a discussion of traditional and emerging models, specialized HF units, the makeup and implementation of multidisciplinary team-based decision-making, and cardiac critical care admission and triage practices. This article illustrates the ways in which critically ill patients with HF have helped to shape contemporary CICUs throughout the world and explores how these very patients will similarly help to inform the future maturation of these specialized critical care units. Finally, we will critically examine broad, contemporary, international models of HF and cardiac critical care delivery in North America, Europe, South America, and Asia, and conclude with opportunities for the further investigation and generation of evidence for care delivery.

Association between operator volume and mortality in primary percutaneous coronary intervention

Background

There is a paucity of real-world data assessing the association of operator volumes and mortality specific to primary percutaneous coronary intervention (PPCI).

Methods

Demographic, clinical and outcome data for all patients undergoing PPCI in Leeds General Infirmary, UK, between 1 January 2009 and 31 December 2011, and 1 January 2013 and 31 December 2013, were obtained prospectively. Operator volumes were analysed according to annual operator PPCI volume (low volume: 1–54 PPCI per year; intermediate volume: 55–109 PPCI per year; high volume: ≥110 PPCI per year). Cox proportional hazards regression analyses were undertaken to investigate 30-day and 12-month all-cause mortality, adjusting for confounding factors.

Results

During this period, 4056 patients underwent PPCI, 3703 (91.3%) of whom were followed up for a minimum of 12 months. PPCI by low-volume operators was associated with significantly higher adjusted 30-day mortality (HR 1.48 (95% CI 1.05 to 2.08); p=0.02) compared with PPCI performed by high-volume operators, with no significant difference in adjusted 12-month mortality (HR 1.26 (95% CI 0.96 to 1.65); p=0.09). Comparisons between low-volume and intermediate-volume operators, and between intermediate and high-volume operators, showed no significant differences in 30-day and 12-month mortality.

Conclusions

Low operator volume is independently associated with higher probability of 30-day mortality compared with high operator volume, suggesting a volume–outcome relationship in PPCI at a threshold higher than current recommendations.

Government Regulation and Percutaneous Coronary Intervention Volume, Access and Outcomes: Insights From the Washington State Cardiac Care Outcomes Assessment Program

Background

It is unclear how to geographically distribute percutaneous coronary intervention (PCI) programs to optimize patient outcomes. The Washington State Certificate of Need program seeks to balance hospital volume and patient access through regulation of elective PCI.

Methods and Results

We performed a retrospective cohort study of all non‐Veterans Affairs hospitals with PCI programs in Washington State from 2009 to 2018. Hospitals were classified as having (1) full PCI services and surgical backup (legacy hospitals, n=17); (2) full services without surgical backup (new certificate of need [CON] hospitals, n=9); or (3) only nonelective PCI without surgical backup (myocardial infarction [MI] access hospitals, n=9). Annual median hospital‐level volumes were highest at legacy hospitals (605, interquartile range, 466–780), followed by new CON, (243, interquartile range, 146–287) and MI access, (61, interquartile range, 23–145). Compared with MI access hospitals, risk‐adjusted mortality for nonelective patients was lower for legacy (odds ratio [OR], 0.59 [95% CI, 0.48–0.72]) and new‐CON hospitals (OR, 0.55 [95% CI, 0.45–0.65]). Legacy hospitals provided access within 60 minutes for 90% of the population; addition of new CON and MI access hospitals resulted in only an additional 1.5% of the population having access within 60 minutes.

Conclusions

Many PCI programs in Washington State do not meet minimum volume standards despite regulation designed to consolidate elective PCI procedures. This CON strategy has resulted in a tiered system that includes low‐volume centers treating high‐risk patients with poor outcomes, without significant increase in geographic access. CON policies should re‐evaluate the number and distribution of PCI programs.

Timing of Repair in Postinfarction Ventricular Septal Defect

The optimal timing of postinfarction ventricular septal defect (PI-VSD) repair is subject to debate. Patients with ventricular septal defect (VSD) and ST-elevation myocardial infarction (STEMI) were queried using appropriate International Classification of Diseases, Ninth and Tenth Revision Clinical Modification codes from the National Inpatient Sample (2003 to 2018). VSD repair was identified using appropriate International Classification of Diseases, Ninth and Tenth Revision Procedure Coding System codes. Data were stepwise stratified by cardiogenic shock (CS) and time of repair from admission to create 6 clinically relevant groups: shock 1 (CS; 0 to 7 days), shock 2 (CS; 8 to 14 days), and shock 3 (CS; >14 days). Nonshock groups were classified similarly. The primary outcome was in-hospital mortality. Multilevel hierarchical logistic regression was used to adjust for confounders for each group. We identified 10,902 patients with PI-VSD. In shock 1 (n = 5,794), VSD repair was associated with lower mortality (OR 0.76; 95% CI 0.68 to 0.86, p <0.001) compared to no VSD repair. In shock 2 (n=1,009) mortality was numerically lower in those who received VSD repair, but not statistically different. In shock 3 (n=483), mortality was numerically higher in those who received VSD repair, but not statistically different. In nonshock 1 (n=5,108), VSD repair was associated with higher mortality (odds ratio [OR] 1.59; 95% confidence interval [CI] 1.33 to 1.90; p <0.001). In nonshock 2 (n = 1,265), mortality was numerically higher in patients with VSD repair, although not statistically different. In nonshock 3 (n = 472), mortality was numerically lower in patients with VSD repair, although not statistically different. Mechanical circulatory support use increased over the 16 years (relative change + 18%, p <0.001), with no significant change in mortality among patients with PI-VSD. In conclusion, in patients with CS, early PI-VSD repair was associated with lower mortality. However, in patients without CS, early PI-VSD repair was associated with higher mortality.

Variation in in-hospital mortality and its association with percutaneous coronary intervention-related bleeding complications: A report from nationwide registry in Japan

Large-scale registries have demonstrated that in-hospital mortality after percutaneous coronary intervention (PCI) varies widely across institutions. However, whether this variation is related to major procedural complications (e.g., bleeding) is unclear. In this study, institutional variation in in-hospital mortality and its association with PCI-related bleeding complications were investigated. We analyzed 388,866 procedures at 718 hospitals performed from 2017 to 2018, using data from a nationwide PCI registry in Japan. Hospitals were stratified into quintiles according to risk-adjusted in-hospital mortality (very low, low, medium, high, and very high). Incidence of bleeding complications, defined as procedure-related bleeding events that required a blood transfusion, and in-hospital mortality in patients who developed bleeding complications were calculated for each quintile. Overall, 4,048 (1.04%) in-hospital deaths and 1,535 (0.39%) bleeding complications occurred. Among patients with bleeding complications, 270 (17.6%) died during hospitalization. In-hospital mortality ranged from 0.22% to 2.46% in very low to very high mortality hospitals. The rate of bleeding complications varied modestly from 0.27% to 0.57% (odds ratio, 1.95; 95% confidence interval, 1.58–2.39). However, mortality after bleeding complications markedly increased by quintile and was 6-fold higher in very high mortality hospitals than very low mortality hospitals (29.0% vs. 4.8%; odds ratio, 12.2; 95% confidence interval, 6.90–21.7). In conclusion, institutional variation in in-hospital mortality after PCI was associated with procedure-related bleeding complications, and this variation was largely driven by differences in mortality after bleeding complications rather than difference in their incidence. These findings underscore the importance of efforts toward reducing not only bleeding complications but also, even more importantly, subsequent mortality once they have occurred.

Percutaneous Coronary Intervention Operator Profiles and Associations With In-Hospital Mortality

BACKGROUND

Percutaneous coronary intervention is performed by operators with differing experience, technique, and case mix. It is unknown if operator practice patterns impact patient outcomes. We sought to determine if a cluster algorithm can identify distinct profiles of percutaneous coronary intervention operators and if these profiles are associated with patient outcomes.

METHODS

Operators performing at least 25 annual procedures between 2014 and 2018 were clustered using an agglomerative hierarchical clustering algorithm. Risk-adjusted in-hospital mortality was compared between clusters.

RESULTS

We identified 4 practice profiles among 7706 operators performing 2 937 419 procedures. Cluster 1 (n=3345) demonstrated case mix and practice patterns similar to the national median. Cluster 2 (n=1993) treated patients with lower clinical acuity and were less likely to use intracoronary diagnostics, atherectomy, and radial access. Cluster 3 (n=1513) had the lowest case volume, were more likely to work at rural hospitals, and cared for a higher proportion of patients with ST-segment-elevation myocardial infarction and cardiogenic shock. Cluster 4 (n=855) had the highest case volume, were most likely to treat patients with high anatomic complexity and use atherectomy, intracoronary diagnostics, and mechanical support. Compared with cluster 1, adjusted in-hospital mortality was similar for cluster 2 (estimated difference, -0.03 [95% CI, -0.10 to 0.04]), higher for cluster 3 (0.14 [0.07-0.22]), and lower for cluster 4 (-0.15 [-0.24 to -0.06]).

CONCLUSIONS

Distinct percutaneous coronary intervention operator profiles are differentially associated with patient outcomes. A phenotypic approach to physician assessment may provide actionable feedback for quality improvement.

The Effect of Clinical Volume on Annual and Per-Patient Encounter Medical Malpractice Claims Risk

OBJECTIVES

The relationship between medical malpractice risk and one of the fundamental characteristics of physician practice, clinical volume, remains undefined. This study examined how the annual and per-patient encounter medical malpractice claims risk varies with clinical volume.

METHODS

Clinical volume was determined using health insurance charges and was linked at the physician level to malpractice claims data from a malpractice insurer. The annual medical malpractice claims risk was expressed as the percent of physicians with a malpractice claim, and the per-encounter medical malpractice claims risk was expressed as malpractice claims per 1000 patient encounters. Both of these malpractice claims risk metrics were analyzed as a function of clinical volume, using linear and spline regression.

RESULTS

As clinical volume increased, the percent of physicians with a malpractice claim increased linearly. Among all physicians studied, for each decile increase in clinical volume, there was a 0.373% increase in physicians with a malpractice claim (95% confidence interval, 0.301%-0.446%; P < 0.0001). As clinical volume increased, the rate of malpractice claims per 1000 patient encounters decreased. This relationship between clinical volume and per-encounter claims risk was nonlinear. There was a clinical volume threshold, below which decreasing clinical volume was associated with increasing per-encounter claims risk, and above which claims risk no longer significantly varied with increases in clinical volume.

CONCLUSIONS

Clinical volume is a crucial determinant of physician malpractice risk, with higher-volume physicians having higher annual risk but lower per-encounter risk. Clinical volume data should be incorporated into analyses of malpractice risk.

Clinical and Economic Burden of Percutaneous Coronary Intervention in Hospitalized Young Adults in the United States, 2004-2018

BACKGROUND

The clinical and economic burden of percutaneous coronary intervention (PCI) in young adults (<45 years) is understudied.

METHODS AND RESULTS

We used the National Inpatient Sample database between 2004 and 2018 to study trends in PCI volume, in-hospital mortality, length of stay (LOS), and health care expenditure among adults aged 18- 44 years who underwent PCI. The data were weighted to explore national estimates of the entire US hospitalized population. We identified 558,611 PCI cases, equivalent to 31.4 per 1,000,000 person-years; 25.4% were women, and 69.5% were White adults. Overall, annual PCI volume significantly decreased from 41.6 per 100,000 in 2004 to 21.9 per 100,000 in 2018, mainly due to 83% volume reduction in non-myocardial infarction (MI) cases. The prevalence of cardiometabolic comorbidities, smoking, and drug abuse increased. Overall, in-hospital mortality was 0.87%; women had higher mortality than men (1.12% vs. 0.78%; P=0.01). The crude and risk-adjusted in-hospital mortality significantly increased between 2004 and 2018. Women, STEMI, NSTEMI, drug abuse, heart failure, peripheral vascular disease, and renal failure were associated with higher odds of in-hospital mortality. Inflation-adjusted cost significantly increased over time ($21,567 to $24,173).

CONCLUSION

We noted reduction in PCI volumes but increasing mortality and clinical comorbidities among young patients undergoing PCI. Demographic disparities existed with women having higher in-hospital mortality than men.

Impact of Center Volume on Outcomes in Myocardial Infarction Complicated by Cardiogenic Shock: A CULPRIT-SHOCK Substudy

Background

Little is known about the impact of center volume on outcomes in acute myocardial infarction complicated by cardiogenic shock. The aim of this study was to investigate the association between center volume, treatment strategies, and subsequent outcome in patients with acute myocardial infarction complicated by cardiogenic shock.

Methods and Results

In this subanalysis of the randomized CULPRIT‐SHOCK (Culprit Lesion Only PCI Versus Multivessel PCI in Cardiogenic Shock) trial, study sites were categorized based on the annual volume of acute myocardial infarction complicated by cardiogenic shock into low‐/intermediate‐/high‐volume centers (<50; 50–100; and >100 cases/y). Subjects from the study/compulsory registry with available volume data were included. Baseline/procedural characteristics, overall treatment, and 1‐year all‐cause mortality were compared across categories. n=1032 patients were included in this study (537 treated at low‐volume, 240 at intermediate‐volume, and 255 at high‐volume centers). Baseline risk profile of patients across the volume categories was similar, although high‐volume centers included a larger number of older patients. Low‐/intermediate‐volume centers had more resuscitated patients (57.5%/58.8% versus 42.2%; P<0.01), and more patients on mechanical ventilation in comparison to high‐volume centers. There were no differences in reperfusion success despite considerable differences in adjunctive pharmacological/device therapies. There was no difference in 1‐year all‐cause mortality across volume categories (51.1% versus 56.5% versus 54.4%; P=0.34).

Conclusions

In this study of patients with acute myocardial infarction complicated by cardiogenic shock, considerable differences in adjunctive medical and mechanical support therapies were observed. However, we could not detect an impact of center volume on reperfusion success or mortality.

Use of Echocardiography and Heart Failure In-Hospital Mortality from Registry Data in Japan

Background: Echocardiography requires a high degree of skill on the part of the examiner, and the skill may be more improved in larger volume centers. This study investigated trends and outcomes associated with the use and volume of echocardiographic exams from a real-world registry database of heart failure (HF) hospitalizations. Methods: This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). A first analysis was performed to assess the trend of echocardiographic examinations between 2012 and 2016. A secondary analysis was performed to assess whether echocardiographic use was associated with in-hospital mortality in 2015. Results: During this period, the use of echocardiography grew at an average annual rate of 6%. Patients with echocardiography had declining rates of hospital mortality, and these trends were associated with high hospitalization costs. In the 2015 sample, a total of 52,832 echocardiograms were examined, corresponding to 65.6% of all HF hospital admissions for that year. We found that the use and volume of echocardiography exams were associated with significantly lower odds of all-cause hospital mortality in heart failure (adjusted odds ratio (OR): 0.48 for use of echocardiography and 0.78 for the third tertile; both p < 0.001). Conclusions: The use of echocardiography was associated with decreased odds of hospital mortality in HF. The volumes of echocardiographic examinations were also associated with hospital mortality.

Quality metrics in the performance of EUS: a population-based observational cohort of the United States

BACKGROUND AND AIMS

There are few data on the quality of EUS in the community setting. We characterized EUS performance at the individual facility level in 3 large American states, using need for repeat biopsy (NRB) as a metric for procedural failure, and the rate of unplanned hospital encounters (UHEs) as a metric for adverse events.

METHODS

We collected data on 76,614 EUS procedures performed at 166 facilities in California, Florida, and New York (2009-2014). The endpoints for the study were 7-day rate of UHEs after EUS, and 30-day rate of NRB after EUS with fine-needle aspiration. Facility-level factors analyzed included annual procedure volume, urban/rural location, and free-standing status (facilities not attached to a larger hospital). Predictors for UHE and NRB were analyzed in both multivariable regression and nonparametric local regression.

RESULTS

Facility volume did not predict risk for UHEs. However, high facility volume protected against NRB (P trend <.001) even after adjustment for other facility-level factors. When regressing facility volume against risk for NRB in local regression, a join point (inflection point) was identified at 97 procedures per annum. Once facilities reached this threshold volume, there appeared little additional protective effect of higher volume. Rural facility location (odds ratio, 1.81; 95% confidence interval, 1.36-2.40) and free-standing status (odds ratio, 1.57; 95% confidence interval, 1.16-2.13) were also associated with NRB.

CONCLUSION

Facility volume does not predict risk for adverse events after EUS. However, high facility volume is associated with decreased rates of technical failure (as assessed by NRB). These data provide one of the first descriptions of EUS practice in community settings and highlight opportunities to improve endoscopic quality nationally.

Operator Volumes and In-Hospital Outcomes: An Analysis of 7,740 Rotational Atherectomy Procedures From the BCIS National Database

OBJECTIVES

The aims of this study were to use a national percutaneous coronary intervention (PCI) registry to study temporal changes in procedure volumes of PCI using rotational atherectomy (ROTA-PCI), the patient and procedural factors associated with differing quartiles of operator ROTA-PCI volume, and the relationship between operator ROTA-PCI volumes and in-hospital patient outcomes.

BACKGROUND

Whether higher operator volume is associated with improved outcomes after ROTA-PCI is poorly defined.

METHODS

Data from the British Cardiovascular Intervention Society national PCI database were analyzed for all ROTA-PCI procedures performed in the United Kingdom between 2013 and 2016. Individual logistic regressions were performed to quantify the independent association between annual operator ROTA-PCI volume and in-hospital outcomes.

RESULTS

In total, 7,740 ROTA-PCI procedures were performed, with a negatively skewed distribution and an annualized operator volume median of 2.5 procedures/year (range 0.25 to 55.25). Higher volume operators undertook more complex procedures in patients with greater comorbid burdens than lower volume operators. A significant inverse association was observed between operator ROTA-PCI volume and in-hospital mortality (odds ratio [OR]: 0.986/case; 95% confidence interval [CI]: 0.975 to 0.996; p = 0.007) and major adverse cardiac and cerebral events (OR: 0.983/case; 95% CI: 0.975 to 0.993; p < 0.001). Additionally, lower rates of emergency cardiac surgery (OR: 0.964/case; 95% CI: 0.939 to 0.991; p = 0.008), arterial complications (OR: 0.975/case; 95% CI: 0.975 to 0.982; p < 0.001) and in-hospital major bleeding (OR: 0.985/case; 95% CI: 0.977 to 0.993; p < 0.001) were associated with higher ROTA-PCI operator volume. Sensitivity analyses in several subgroups demonstrated a consistency of improved outcomes as annual ROTA-PCI volume increased. An annual volume of <4 ROTA-PCI procedures/year was observed to be associated with increased major adverse cardiac and cerebral events, with 239 of 432 operators (55%) not exceeding this threshold.

CONCLUSIONS

In-hospital adverse outcomes occurred less frequently as ROTA-PCI operator volume increased. These data suggest that operator volume is an important factor determining outcome after ROTA-PCI.

The relationship between procedural volume and patient outcomes for percutaneous coronary interventions: a systematic review and meta-analysis

Background: The relationship between procedural volume and outcomes for percutaneous coronary interventions (PCI) is contentious, with previous reviews suggesting an inverse volume-outcome relationship. The aim of this study was to systematically review contemporary evidence to re-examine this relationship.

Methods: A systematic review and meta-analysis was undertaken to examine the relationship between PCI procedural volume (both at hospital- and operator-levels) and outcomes in adults. The primary outcome was mortality. The secondary outcomes were complications, healthcare utilisation and process outcomes. Searches were conducted from 1 January 2008 to 28 May 2019. Certainty of the evidence was assessed using ‘Grading of Recommendations, Assessment, Development and Evaluations’ (GRADE). Screening, data extraction, quality appraisal and GRADE assessments were conducted independently by two reviewers.

Results: Of 1,154 unique records retrieved, 22 observational studies with 6,432,265 patients were included. No significant association was found between total PCI hospital volume and mortality (odds ratio [OR]: 0.84, 95% confidence interval [CI]: 0.69-1.03, I ² = 86%). A temporal trend from significant to non-significant pooled effect estimates was observed. The pooled effect estimate for mortality was found to be significantly in favour of high-volume operators for total PCI procedures (OR: 0.77, 95% CI: 0.63-0.94, I ² = 93%), and for high-volume hospitals for primary PCI procedures (OR: 0.77, 95% CI: 0.62-0.94, I ² = 78%). Overall, GRADE certainty of evidence was ‘very low’. There were mixed findings for secondary outcomes.

Conclusions: A volume-outcome relationship may exist in certain situations, although this relationship appears to be attenuating with time, and there is ‘very low’ certainty of evidence. While volume might be important, it should not be the only standard used to define an acceptable PCI service and a broader evaluation of quality metrics should be considered that encompass patient experience and clinical outcomes.

Systematic review registration: PROSPERO, CRD42019125288

Cardiogenic shock teams and centres: a contemporary review of multidisciplinary care for cardiogenic shock

Cardiogenic shock (CS) portends high morbidity and mortality in the contemporary era. Despite advances in temporary mechanical circulatory supports (MCS), their routine use in CS to improve outcomes has not been established. Delays in diagnosis and timely delivery of care, disparities in accessing adjunct therapies such revascularization or MCS, and lack of a systematic approach to care of CS contribute to the poor outcomes observed in CS patients. There is growing interest for developing a standardized multidisciplinary team-based approach in the management of CS. Recent prospective studies have shown feasibility of CS teams in improving survival across a spectrum of CS presentations. Herein, we will review the rationale for CS teams focusing on evidence supporting its use in streamlining care, optimizing revascularization strategies, and patient identification and MCS selection. The proposed structure and flow of CS teams will be outlined. An in-depth analysis of four recent studies demonstrating improved outcomes with CS teams is presented. Finally, we will explore potential implementation hurdles and future directions in refining and widespread implementation of dedicated cross-specialty CS teams.

Population Density Analysis of Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction in Japan

Background

Despite recent progress in the treatment of ST‐segment–elevation myocardial infarction, data on geographic disparities application of the evidence‐based therapy remain limited.

Methods and Results

The J‐PCI (Japanese Percutaneous Coronary Intervention) registry is a nationwide registry to assure the quality of delivered care. Between January 2014 and December 2018, 209 521 patients underwent percutaneous coronary intervention for ST‐segment–elevation myocardial infarction in 1126 institutions. The patients were divided into tertiles according to the population density (PD) of the percutaneous coronary intervention institution location (low: <951.7/km², n = 69 797; medium: 951.7–4729.7/km², n = 69 750; high: ≥4729.7/km², n = 69 974). Patients treated in high PD administrative districts were younger and more likely to be male. No significant correlation was observed between PD and door‐to‐balloon time (regression coefficients: 0.036 per 1000 people/km²; 95% CI, −0.232 to 0.304; P = 0.79). Patients treated in low‐PD areas had higher crude in‐hospital mortality rates than those treated in high‐PD areas (low: 2.89%; medium: 2.60%; high: 2.38%; P < 0.001); PD and in‐hospital mortality had a significantly inverse association, before and after adjusting for baseline characteristics (crude odds ratio [OR], 0.983 per 1000/km²; 95% CI, 0.973–0.992; P < 0.001; adjusted OR, 0.980 per 1000/km²; 95% CI, 0.964–0.996; P = 0.01, respectively). Higher‐PD districts had more operators per institution (low: 6; interquartile range, 3–10; medium: 7; IQR, 3–13; high: 8; IQR, 5–13; P < 0.001), suggesting an inverse association with in‐hospital mortality (OR, 0.992; 95% CI, 0.986–0.999; P = 0.03).

Conclusions

Geographic inequality was observed in in‐hospital mortality of patients with ST‐segment–elevation myocardial infarction who underwent percutaneous coronary intervention. Variation in the number of operators per institution, rather than traditional quality indicators (eg, door‐to‐balloon time) might explain the difference in in‐hospital mortality.

Mitral valve surgery for ischemic papillary muscle rupture: outcomes from the Japan cardiovascular surgery database

Background

Ischemic papillary muscle rupture (PMR) is a catastrophic complication following acute myocardial infarction (AMI). We evaluated early outcomes of PMR by using data from the Japan Cardiovascular Surgery Database, a nationwide Japanese registry.

Methods

We retrospectively analyzed data from 196 patients diagnosed with PMR following AMI in Japan between January 2014 and December 2017. Risk factors for operative mortality and severe complications following mitral valve surgery were analyzed.

Results

The 30-day and hospital mortality rates were 20% and 26%, respectively. Chronic hemodialysis, abrupt rupture after AMI, resuscitation before surgery, and preoperative venoarterial extracorporeal membrane oxygenation were associated with mortality. Mitral valve replacement was chosen mainly (90%) for surgical correction of mitral regurgitation in these patients. There was no significant difference in short-term outcomes between mitral valve replacement versus mitral valve repair, despite non-matched characteristics in background between the treatment groups. Concomitant coronary artery bypass grafting had no impact on short-term outcomes.

Conclusions

Information derived from the nationwide database of patients with AMI-associated PMR show that PMR is a rare condition in the modern era. However, PMR is a severe disease with a mortality rate as high as 26%. The severity of the condition is associated with the risk for poor outcomes.

Electronic supplementary material

The online version of this article (10.1007/s11748-020-01418-y) contains supplementary material, which is available to authorized users.

Procedural volume and outcomes in patients undergoing VA-ECMO support

Background

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used in patients with critical cardiopulmonary failure. To investigate the association between hospital VA-ECMO procedure volume and outcomes in a large, nationwide registry.

Methods

By using administrative data from the German Federal Health Monitoring System, we analyzed all VA-ECMO procedures performed in Germany from 2013 to 2016 regarding the association of procedural volumes with outcomes and complications.

Results

During the study period, 10,207 VA-ECMO procedures were performed; mean age was 61 years, 43.4% had prior CPR, and 71.2% were male patients. Acute coronary syndrome was the primary diagnosis for VA-ECMO implantation (n = 6202, 60.8%). The majority of implantations (n = 5421) were performed at hospitals in the lowest volume category (≤ 50 implantations per year).

There was a significant association between annualized volume of VA-ECMO procedures and 30-day in-hospital mortality for centers with lower vs. higher volume per year. Multivariable logistic regression showed an increased 30-day in-hospital mortality at hospitals with the lowest volume category (adjusted odds ratio 1.13, 95% confidence interval [CI] 1.01–1.27, p = 0.034).

Similarly, higher likelihood for complications was observed at hospitals with lower vs. higher annual VA-ECMO volume (adjusted odds ratio 1.46, 95% CI 1.29–1.66, p = 0.001).

Conclusions

In this analysis of more than 10,000 VA-ECMO procedures for cardiogenic shock, the majority of implantations were performed at hospitals with the lowest annual volume. Thirty-day in-hospital mortality and likelihood for complications were higher at hospitals with the lowest annual VA-ECMO volume.

Are Higher Operator Volumes for Unprotected Left Main Stem Percutaneous Coronary Intervention Associated With Improved Patient Outcomes?

Background:

The relationship between operator volume and survival after unprotected left main stem percutaneous coronary intervention (uLMS-PCI) is poorly defined.

Methods:

Data from the British Cardiovascular Intervention Society national PCI database were analyzed for all uLMS-PCI procedures performed in England and Wales between 2012 and 2014 and 4 quartiles of annualized uLMS-PCI volume (Q1–Q4) generated. Individual logistic regressions were performed for 12-month mortality to quantify the independent association between operator quartile and outcomes.

Results:

In total, 6724 uLMS-PCI procedures were analyzed with a negatively skewed distribution and an annualized median of 3 procedures per year. Operator volume ranged from 1 to 54 uLMS-PCI procedures/year. Within Q1, 347 operators performed a median of 2 procedures/year (interquartile range, 1–3); in Q2, 134 operators performed a median of 5 procedures/year (interquartile range, 4–6); in Q3, 59 operators performed a mean of 10 procedures/year (interquartile range, 8–12); and in Q4, 29 operators performed a mean of 21 procedures/year (interquartile range, 17–29). Higher volume operators undertook uLMS-PCI in patients with greater comorbid burden and performed more complex procedures compared with lower operator volumes. Adjusted in-hospital survival (odds ratio, 0.39 [95% CI, 0.24–0.67]; P <0.001), in-hospital major adverse cardiac and cerebral events (odds ratio, 0.41 [95% CI, 0.27–0.62]; P <0.001), and 12-month survival (odds ratio, 0.54 [95% CI, 0.39–0.73]; P <0.001) were lower in Q4 operators compared with Q1 operators. A close association between operator volume/case and superior 12-month survival was observed ( P <0.001). The lower volume threshold of minimum operator uLMS-PCI volume associated with improved survival was ≥16 cases/year.

Conclusions:

These data suggest that operator volume is an important factor in determining outcome after uLMS-PCI.

Procedural Volume and Outcomes After Percutaneous Coronary Intervention for Unprotected Left Main Coronary Artery Disease-Report From the National Clinical Data (J-PCI Registry)

Background There is a limited evidence base to support the volume-outcome relationship in patients undergoing percutaneous coronary intervention (PCI) for unprotected left main coronary artery disease (UPLMD). This study aimed to evaluate the relationship between institutional and operator volume and in-hospital outcomes in patients undergoing PCI for unprotected left main coronary artery disease. Methods and Results We analyzed characteristics and clinical outcomes of 24 320 patients undergoing PCI for unprotected left main coronary artery disease at 1102 hospitals by 7244 operators using data from the Japanese nationwide J-PCI Registry (National PCI Data Registry) between January 2014 and December 2017. We classified institutions and operators into quartiles based on the mean annual volume of PCI. A generalized linear mixed-effects model was used to evaluate the association between institutional and operator PCI volume and in-hospital outcomes. Among the 24 320 patients, 4027 (16.6%), 6147 (25.3%), and 14 146 (58.2%) presented with ST-segment-elevation myocardial infarction, non-ST-segment-elevation acute coronary syndrome, and stable ischemic heart disease; their crude in-hospital mortality was 15%, 3.1%, and 0.3%, respectively. Compared with patients in the lowest quartile of institutional volume (1-216 PCIs/y), the adjusted odds ratio of in-hospital death in patients in the second (217-323 PCIs/y), third (324-487 PCIs/y), and fourth (488-3015 PCIs/y) quartile of institutional volume was 0.75 (95% CI, 0.51-1.10; P=0.14), 0.87 (95% CI, 0.57-1.34; P=0.54), and 0.51 (95% CI, 0.30-0.86; P=0.01), respectively. These findings were consistent in rates of in-hospital death or any complication. Conversely, operator PCI volume was not significantly associated with in-hospital outcomes. Conclusions Institutional rather than operator-based PCI volume was associated with better in-hospital outcomes in patients undergoing PCI for unprotected left main coronary artery disease.

Outcomes and Hospital Utilization in Patients With Papillary Muscle Rupture Associated With Acute Myocardial Infarction

Papillary muscles rupture (PMR) is a rare complication of acute myocardial infarction (MI) that can lead to severe hemodynamic compromise, acute heart failure, and death. This study was designed to assess demographics, outcomes, and hospital utilization trends in the management of PMR associated with acute MI. Data were derived from the National Inpatient Sample for the years 2005 to 2014. ICD-9 codes 410.0 to 410.9 were used to identify patients with acute MI. ICD-9 code 429.6 was used to identify patients with PMR. ICD-9 procedures codes 35.23, 35.24, and 35.12 were used to identify patients who underwent mitral valve replacement (MVR) or repair. Of the 3,244,799 admissions, 932 were complicated by PMR (incidence of 0.029%). The majority of patients with PMR were ≥65 years old (60.1%) and male (60.4%). Of those with PMR, 57.5% underwent MVR. Compared to patients without PMR, those with PMR had a significantly higher in-hospital mortality rate (5.3 vs 36.3%, p <0.001), cost of hospitalization ($20,205 vs $74,383, p <0.001) and length of hospital stay (4.67 ± 02 vs 11.2 ± 0.80 days, p <0.001). Predictors of in-hospital mortality in PMR patients were age, inferior wall acute MI, and cardiac arrest. Predictors of MVR in PMR patients were age, female gender, concomitant coronary artery bypass grafting, mechanical circulatory support, longer length of stay, and admission to a large hospital. In conclusion, patients with PMR associated with acute MI have higher risk of in-hospital mortality, greater cost of hospitalization and longer length of stay than patients acute MI without PMR.

Relation Between Operator and Hospital Volumes and Long-Term Outcomes for Percutaneous Coronary Intervention in New York

Little is known about whether there is an inverse relation between provider volume and long-term adverse outcomes for percutaneous coronary interventions (PCIs). For patients who underwent PCI procedures from December 2013 through November 2014 in New York, we examined a continuous relation and different annual PCI volume cut points at hospital and operator levels to investigate the relation between volume and 1-year adverse outcomes (mortality and mortality/acute myocardial infarction). There were 34,498 patients who underwent PCI procedures from 60 hospitals and 408 operators. We detected a significant continuous inverse association between 1-year mortality and annual hospital PCI volume. However, we did not find that there was a hospital volume and 1-year mortality relation for the 2013 ACCF/AHA/SCAI's hospital annual PCI volume cutoff value of 200 or a significant inverse operator volume-outcome relation using the operator annual PCI volume cutoff value of 50, or for any other practical volume cutoffs. Similar findings were obtained when we used the 1-year mortality/acute myocardial infarction outcome. We did find that providers in the highest volume quartile were associated with lower adverse outcome rates than providers in the lowest volume quartile. In conclusion, no significant volume-outcome relations were found between annual hospital or operator PCI volume and risk-adjusted 1-year outcomes for any practical volume cutoff values including 2013 Guidelines' recommended hospital/operator minimal annual PCI volumes. Providers in the highest annual volume quartile, however, were associated with lower adverse outcome rates than providers in the lowest volume quartile.

Trends in Characteristics and Outcomes of Patients Undergoing Coronary Revascularization in the United States, 2003-2016

IMPORTANCE

Data on the contemporary changes in risk profile and outcomes of patients undergoing percutaneous coronary intervention (PCI) or coronary bypass grafting (CABG) are limited.

OBJECTIVE

To assess the contemporary trends in the characteristics and outcomes of patients undergoing PCI or CABG in the United States.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used a national inpatient claims-based database to identify patients undergoing PCI or CABG from January 1, 2003, to December 31, 2016. Data analysis was performed from July 15 to October 4, 2019.

MAIN OUTCOMES AND MEASURES

Demographic characteristics, prevalence of risk factors, and clinical presentation divided into 3 eras (2003-2007, 2008-2012, and 2013-2016) and in-hospital mortality of PCI and CABG stratified by clinical indication.

RESULTS

A total of 12 062 081 revascularization hospitalizations were identified: 8 687 338 PCIs (72.0%; mean [SD] patient age, 66.0 [10.8] years; 66.2% male) and 3 374 743 CABGs (28.0%; mean [SD] patient age, 64.5 [12.4] years; 72.1% male). The annual PCI volume decreased from 366 to 180 per 100 000 US adults and the annual CABG volume from 159 to 82 per 100 000 US adults. A temporal increase in the proportions of older, male, nonwhite, and lower-income patients and in the prevalence of atherosclerotic and nonatherosclerotic risk factors was found in both groups. The percentage of revascularization for myocardial infarction (MI) increased in the PCI group (22.8% to 53.1%) and in the CABG group (19.5% to 28.2%). Risk-adjusted mortality increased slightly after PCI for ST-segment elevation MI (4.9% to 5.3%; P < .001 for trend) and unstable angina or stable ischemic heart disease (0.8% to 1.0%; P < .001 for trend) but remained stable after PCI for non-ST-segment elevation MI (1.6% to 1.6%; P = .18 for trend). Risk-adjusted CABG morality markedly decreased in patients with MI (5.6% to 3.4% for all CABG and 4.8% to 3.0% for isolated CABG) and in those without MI (2.8% to 1.7% for all CABG and 2.1% to 1.2% for isolated CABG) (P < .001 for all).

CONCLUSIONS AND RELEVANCE

Significant changes were found in the characteristics of patients undergoing PCI and CABG in the United States between 2003 and 2016. Risk-adjusted mortality decreased significantly after CABG but not after PCI across all clinical indications.

Improvement of clinical outcome in patients with ST-elevation myocardial infarction between 1999 and 2016 in China: The Prospective, Multicentre Registry MOODY study

BACKGROUND

Reports showed no change of 7-day mortality after primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) between 2001 and 2011 in China. National rolling one-year interventional standardized training programme began in September 2009. However, the improvement in clinical outcome following STEMI PCI after 2011 remains unclear.

METHODS AND RESULTS

This multicentre MOODY registry study aimed to analyse the clinical improvement after STEMI PCI. Of a total of 9265 acute MI patients registered from 24 centres, 3142 STEMIs having a first medical contact time ≤12 hours and undergoing primary PCI were assigned to the Pre Group (n = 1014, between March 1999 and October 2010) or the Post Group (n = 2128, between 2010 November and 2016 October). The primary endpoint was in-hospital cardiac death. Study endpoints were also compared between trained and untrained operators and between experienced (≥50 primary PCIs/year) and inexperienced personnel. In-hospital death after PCI was 3.0% in the Pre Group, significantly higher than 1.6% in the Post Group (P = .035). The improvements in clinical outcome after PCI between the 2016 and Pre Groups were stably sustained through one-year follow-up. The significant reduction for in-hospital death was noted when primary PCI was performed by trained (1.4% vs 5.4%, P < .001) or experienced (2.7% vs 4.8%, P = .001) operators, compared to untrained or inexperienced operators, respectively. Inclusion of the untrained operator into the conventional risk model strongly enhanced the prediction for endpoints. Age, Killip Class 3, diabetes, trans-radial approach and system delay were five predictors of in-hospital death after primary PCI.

CONCLUSION

PCI for STEMI by a trained and experienced operator was associated with significant reduction of in-hospital death. Our results strongly warrant the need for promoting the current system response and patient education.

Impact of Board-Certified Cardiologist Characteristics on Risk of In-Hospital Mortality

Background: This study examined the influence of board-certified cardiologist characteristics on the in-hospital mortality of patients with cardiovascular disease.

Methods and Results: Data were collected between 2012 and 2014 from a nationwide database of acute care hospitals in Japan. Overall, there were 1,422,703 patients, of whom 883,746 were analyzed. The primary outcome was all-cause in-hospital mortality. The association between board-certified cardiologist characteristics and in-hospital mortality was estimated using multilevel mixed-effect logistic regression modeling. Median age of cardiologists in a hospital was not related to in-hospital mortality (OR, 1.003; 95% CI: 0.998–1.008, P=0.316), but a greater cardiologist age range was associated with a lower risk of in-hospital mortality (OR, 0.992; 95% CI: 0.988–0.995 per 1-unit increment in age range, P<0.001). Meanwhile, the average years of experience of the board-certified cardiologists in a hospital was not associated with a lower risk of in-hospital mortality (OR, 1.002; 95% CI: 0.996–1.007, P=0.525), but a greater range of years of experience was (OR, 0.986; 95% CI: 0.983–0.990 per 1-unit increment in range of years of experience, P<0.001).

Conclusions: Median board-certified cardiologist age/experience at an institution is not related to in-hospital mortality, but a greater range in age/experience is associated with a lower risk of mortality.

Impact of Hospital Volume of Percutaneous Coronary Intervention (PCI) on In-Hospital Outcomes in Patients with Acute Myocardial Infarction: Based on the 2014 Cohort of the Korean Percutaneous Coronary Intervention (K-PCI) Registry

Background and Objectives

The relationship between the hospital percutaneous coronary intervention (PCI) volumes and the in-hospital clinical outcomes of patients with acute myocardial infarction (AMI) remains the subject of debate. This study aimed to determine whether the in-hospital clinical outcomes of patients with AMI in Korea are significantly associated with hospital PCI volumes.

Methods

We selected and analyzed 17,121 cases of AMI, that is, 8,839 cases of non-ST-segment elevation myocardial infarction and 8,282 cases of ST-segment elevation myocardial infarction, enrolled in the 2014 Korean percutaneous coronary intervention (K-PCI) registry. Patients were divided into 2 groups according to hospital annual PCI volume, that is, to a high-volume group (≥400/year) or a low-volume group (<400/year). Major adverse cardiovascular and cerebrovascular events (MACCEs) were defined as composites of death, cardiac death, non-fatal myocardial infarction (MI), stent thrombosis, stroke, and need for urgent PCI during index admission after PCI.

Results

Rates of MACCE and non-fatal MI were higher in the low-volume group than in the high-volume group (MACCE: 10.9% vs. 8.6%, p=0.001; non-fatal MI: 4.8% vs. 2.6%, p=0.001, respectively). Multivariate regression analysis showed PCI volume did not independently predict MACCE.

Conclusions

Hospital PCI volume was not found to be an independent predictor of in-hospital clinical outcomes in patients with AMI included in the 2014 K-PCI registry.

Association between the number of board-certified cardiologists and the risk of in-hospital mortality: a nationwide study involving the Japanese registry of all cardiac and vascular diseases

OBJECTIVES

Although there are 14 097 board-certified cardiologists in Japan, it is unknown whether the number of institutional board-certified cardiologists is related to the prognosis of cardiovascular disease patients.

DESIGN

Cross-sectional analysis.

SETTING

Data were collected from the nationwide database of acute care hospitals in Japan (2371 hospitals) between 2012 and 2013.

PARTICIPANTS

A total of 1 422 703 consecutive patients were initially included in this study, but 518 610 patients were excluded due to age <18 years, missing data or prior hospitalisations; therefore, 896 171 patients comprised the final sample population.

MAIN OUTCOME MEASURES

The primary outcome was in-hospital mortality due to any cause. For the per-hospital analysis, Poisson regression models were used to estimate the association of board-certified cardiologists with in-hospital mortality, adjusted for hospital facilitation. For the per-patient analysis, hierarchical logistic regression models were used to estimate the ORs of the number of institutional board-certified cardiologists, adjusted for patient demographics, diagnoses, therapies and hospital facilities.

RESULTS

The regression model of the per-hospital analysis indicated that the number of board-certified cardiologists was associated with a lower rate ratio of in-hospital mortality (rate ratio, 0.988; 95% CI 0.983 to 0.993; p<0.01). The per-patient analysis indicated that the median age was 73 years and the in-hospital mortality rate was 11.7%. The regression model indicated that the presence of more board-certified cardiologists was associated with a lower risk of in-hospital mortality (OR, 0.980; 95% CI 0.975 to 0.986; p<0.01) after adjustments for hospital facilities, patient characteristics and treatments.

CONCLUSIONS

Among cardiovascular disease patients admitted to acute care hospitals in Japan, the presence of more board-certified cardiologists was associated with a lower risk of in-hospital mortality. These results have implications for national and institutional strategies for determining the required number of board-certified cardiologists.

Effect of Operator Volume on In-Hospital Outcomes Following Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction: Based on the 2014 Cohort of Korean Percutaneous Coronary Intervention (K-PCI) Registry

Background and Objectives

The relationship between operator volume and outcomes of percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) has not been fully investigated. We aimed to investigate the relationship between operator PCI volume and in-hospital outcomes after primary PCI for STEMI.

Methods

Among the total of 44,967 consecutive cases of PCI enrolled in the Korean nationwide, retrospective registry (K-PCI registry), 8,282 patients treated with PCI for STEMI by 373 operators were analyzed. PCI volumes above the 75th percentile (>30 cases/year), between the 75th and 25th percentile (10–30 cases/year), and below the 25th percentile (<10 cases/year) were defined as high, moderate, and low-volume operators, respectively. In-hospital outcomes including mortality, non-fatal myocardial infarction (MI), stent thrombosis, stroke, and urgent repeat PCI were analyzed.

Results

The average number of primary PCI cases performed by 373 operators was 22.2 in a year. In-hospital mortality after PCI for STEMI was 571 cases (6.9%). In-hospital outcomes by operator volume showed no significant differences in the death rate, cardiac death, non-fatal MI, and stent thrombosis. However, the rate of urgent repeat PCI tended to be lower in the high-volume operator (0.6%) than in the moderate-(0.7%)/low-(1.5%) volume operator groups (p=0.095). The adjusted odds ratios for adverse in-hospital outcomes were similar in the 3 groups. Multivariate analysis also showed that operator volume was not a predictor for adverse in-hospital outcomes.

Conclusions

In-hospital outcomes after primary PCI for STEMI were not associated with operator volume in the K-PCI registry.

Relationship Between Operator Volume and Long-Term Outcomes After Percutaneous Coronary Intervention

BACKGROUND

Although many studies show an inverse association between operator procedural volume and short-term adverse outcomes after percutaneous coronary intervention (PCI), the association between procedural volume and longer-term outcomes is unknown.

METHODS

Using the National Cardiovascular Data Registry CathPCI registry data linked with Medicare claims data, we examined the association between operator PCI volume and long-term outcomes among patients ≥65 years of age. Operators were stratified by average annual PCI volume (counting PCIs performed in patients of all ages): low- (<50 PCIs), intermediate- (50-100), and high- (>100) volume operators. One-year unadjusted rates of death and major adverse coronary events (MACEs; defined as death, readmission for myocardial infarction, or unplanned coronary revascularization) were calculated with Kaplan-Meier methods. The proportional hazards assumption was not met, and risk-adjusted associations between operator volume and outcomes were calculated separately from the time of PCI to hospital discharge and from hospital discharge to 1-year follow-up.

RESULTS

Between July 1, 2009, and December 31, 2014, 723 644 PCI procedures were performed by 8936 operators: 2553 high-, 2878 intermediate-, and 3505 low-volume operators. Compared with high- and intermediate-volume operators, low-volume operators more often performed emergency PCI, and their patients had fewer cardiovascular comorbidities. Over 1-year follow-up, 15.9% of patients treated by low-volume operators had a MACE compared with 16.9% of patients treated by high-volume operators ( P=0.004). After multivariable adjustment, intermediate- and high-volume operators had a significantly lower rate of in-hospital death than low-volume operators (odds ratio, 0.91; 95% CI, 0.86-0.96 for intermediate versus low; odds ratio, 0.79; 95% CI, 0.75-0.83 for high versus low). There were no significant differences in rates of MACEs, death, myocardial infarction, or unplanned revascularization between operator cohorts from hospital discharge to 1-year follow-up (adjusted hazard ratio for MACEs, 0.99; 95% CI, 0.96-1.01 for intermediate versus low; hazard ratio, 1.01; 95% CI, 0.99-1.04 for high versus low).

CONCLUSIONS

Unadjusted 1-year outcomes after PCI were worse for older adults treated by operators with higher annual volume; however, patients treated by these operators had more cardiovascular comorbidities. After risk adjustment, higher operator volume was associated with lower in-hospital mortality and no difference in postdischarge MACEs.

Vascular complications associated with percutaneous left ventricular assist device placement: A 10-year US perspective

BACKGROUND

Over the last decade, there has been a significant increase in the use of percutaneous left ventricular assist devices(p-LVADs). p-LVADs are being increasingly used during complex coronary interventions and for acute cardiogenic shock. These large bore percutaneous devices have a higher risk of vascular complications. We examined the vascular complication rates from the use of p-LVAD in a national database.

METHODS

We conducted a secondary analysis of the National In-patient Sample (NIS) dataset from 2005 till 2015. We used the ICD-9-CM procedure codes 37.68 and 37.62 for p-LVAD placement regardless of indications. We investigated common vascular complications, defining them by the validated ICD 9 CM codes. χ² test and t test were used for categorical and continuous variables, respectively for comparison.

RESULTS

A total of 31,263 p-LVAD placements were identified during the period studied. A majority of patients were male (72.68%) and 64.44% were white. The overall incidence of vascular complications was 13.53%, out of which 56% required surgical treatment. Acute limb thromboembolism and bleeding requiring transfusion accounted for 27.6% and 21.8% of all vascular complications. Occurrence of a vascular complication was associated with significantly higher in-hospital mortality (37.77% vs. 29.95%, p < .001), length of stay (22.7 vs. 12.2 days, p < .001) and cost of hospitalization ($ 161,923 vs. $ 95,547, p < .001).

CONCLUSIONS

There is a high incidence of vascular complications with p-LVAD placement including need for vascular surgery. These complications are associated with a higher in-hospital, LOS and hospitalization costs. These findings should be factored into the decision-making for p-LVAD placement.

Impact of Hospital Volume on Clinical Outcomes after Aortoiliac Stenting in Patients with Peripheral Artery Disease

AIM

To investigate the impact of institutional volume on clinical outcomes after aortoiliac (AI) stenting in patients with symptomatic peripheral artery disease (PAD).

METHODS

We analyzed the clinical database from the Observational prospective Multicenter registry study on the Outcomes of peripheral arTErial disease patieNts treated by AngioplaSty tHerapy in the aortoIliac artery (OMOTENASHI) registry. The volume of each institution was evaluated as the number of endovascular therapy (EVT) procedures performed in 2 years (2014-2015). High-volume centers were defined as being in the highest tertile of the procedural volume (≥ 611 EVT procedures in 2 years). Clinical outcomes, treatment strategies, and endovascular procedures were compared between high- and low-volume centers using a propensity score matching.

RESULTS

The propensity score matching extracted 236 pairs of patients (as many patients treated at high-volume centers and 519 patients treated at low-volume centers), with no remarkable intergroup differences in the baseline characteristics. Patients treated at high-volume hospitals had a significantly lower 12-month restenosis rate than that of patients treated at low-volume hospitals (6.5% vs. 15.8%, P=0.032), although comparable outcomes between the two groups included the technical success rate (99.6% vs. 99.8%, P=0.58) and the rate of 30-day major adverse events (0.4% vs. 0.8%, P=0.59).

CONCLUSION

Institutional volume was associated with the 12-month restenosis rate after AI stenting for PAD, although comparable perioperative outcomes were also observed between high-volume and low-volume hospitals.

Site Experience and Outcomes in the Trevo Acute Ischemic Stroke (TRACK) Multicenter Registry

Background and Purpose—

It remains unclear how experience influences outcomes after the advent of stent retriever technology. We studied the relationship between site experience and outcomes in the Trevo Acute Ischemic Stroke multicenter registry.

Methods—

The 24 sites that enrolled patients in the Trevo Acute Ischemic Stroke registry were trichotomized into low-volume (<2 cases/month), medium-volume (2–4 cases/month), and high-volume centers (>4 cases/month). Baseline features, imaging, and clinical outcomes were compared across the 3 volume strata. A multivariable analysis was performed to assess whether outcomes were influenced by site volumes.

Results—

A total of 624 patients were included and distributed as low- (n=188 patients, 30.1%), medium- (n=175, 28.1%), and high-volume (n=261, 41.8%) centers. There were no significant differences in terms of age (mean, 66±16 versus 67±14 versus 65±15; P =0.2), baseline National Institutes of Health Stroke Scale (mean, 17.6±6.5 versus 16.8±6.5 versus 17.6±6.9; P =0.43), or occlusion site across the 3 groups. Median (interquartile range) times from stroke onset to groin puncture were 266 (181.8–442.5), 239 (175–389), and 336.5 (221.3–466.5) minutes in low-, medium-, and high-volume centers, respectively ( P =0.004). Higher efficiency and better outcomes were seen in higher volume sites as demonstrated by shorter procedural times (median, 97 versus 67 versus 69 minutes; P <0.001), higher balloon guide catheter use (40% versus 36% versus 59%; P ≤0.0001), and higher rates of good outcome (90-day modified Rankin Scale [mRS], ≤2; 39% versus 50% versus 53.4%; P =0.02). There were no appreciable differences in symptomatic intracranial hemorrhage or 90-day mortality. After adjustments in the multivariable analysis, there were significantly higher chances of achieving a good outcome in high- versus low-volume (odds ratio, 1.67; 95% CI, 1.03–2.7; P =0.04) and medium- versus low-volume (odds ratio, 1.75; 95% CI, 1.1–2.9; P =0.03) centers, but there were no significant differences between high- and medium-volume centers ( P =0.86).

Conclusions—

Stroke center volumes significantly influence efficiency and outcomes in mechanical thrombectomy.

Do Hospital and Physician Volume Thresholds for the Volume-Outcome Relationship in Heart Failure Exist?

BACKGROUND

Although volume-outcome relationships have been explored for various procedures and interventions, limited information is available concerning the effect of hospital and physician volume on heart failure mortality. Most importantly, little is known about whether there are optimal hospital and physician volume thresholds to reduce heart failure mortality.

OBJECTIVES

We used nationwide population-based data to identify the optimal hospital and physician volume thresholds to achieve optimum mortality and to examine the relative and combined effects of the volume thresholds on heart failure mortality.

METHODS

We analyzed all 20,178 heart failure patients admitted in 2012 through Taiwan's National Health Insurance Research Database. Restricted cubic splines and multilevel logistic regression were used to identify whether there are optimal hospital and physician volume thresholds and to assess the relative and combined relationships of the volume thresholds to 30-day mortality, adjusted for patient, physician, and hospital characteristics.

RESULTS

Hospital and physician volume thresholds of 40 cases and 15 cases a year, respectively, were identified, under which there was an increased risk of 30-day mortality. Patients treated by physicians with previous annual volumes <15 cases had higher 30-day mortality compared with those with previous annual volumes ≥15 cases, and the relationship was stronger in hospitals with previous annual volumes <40 cases.

CONCLUSIONS

This is the first study to identify both the hospital and physician volume thresholds that lead to decreases in heart failure mortality. Identifying the hospital and physician volume thresholds could be applied to quality improvement and physician training.