Association Between Operator Procedure Volume and Patient Outcomes in Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

Procedural volume and outcomes with atrial fibrillation ablation: A report from the NCDR AFib Ablation Registry

BACKGROUND

The association of hospital and physician procedure volume with outcome has not been well evaluated for atrial fibrillation (AF) ablation in contemporary practice.

OBJECTIVE

This study aimed to determine the association between hospital and physician AF ablation volume and procedural success (isolation of all pulmonary veins) and major adverse events (MAEs).

METHODS

Procedures reported to the National Cardiovascular Data Registry AFib Ablation Registry between July 2019 and June 2022 were included. Hospital and physician procedural volumes were annualized and stratified into quartiles to compare outcomes. Three-level hierarchical (patient, hospital, and physician) models were used to assess the procedural volume-outcome relationship.

RESULTS

A total of 70,296 first-time AF ablations at 186 US hospitals were included. Overall, procedural success and MAE rates were 98.5% and 1.0%, respectively. With hospital volume (Q4) as a reference, the likelihood of procedural success was lower for Q1 (odds ratio [OR], 0.44; 95% CI, 0.29-0.68), Q2 (OR, 0.50; 95% CI, 0.33-0.75), and Q3 (OR, 0.60; 95% CI, 0.40-0.89); the results were similarly significant for physician volume. With MAE for hospitals, there was an inverse procedural volume relationship for Q1 (OR, 1.78; 95% CI, 1.26-2.52) but not for Q2 (OR, 1.06; 95% CI, 0.77-1.46) or Q3 (OR, 1.19; 95% CI, 0.89-1.58) and similarly for physicians in Q1 and Q2 but not in Q3. An adjusted MAE ≤1% was predicted by an annual volume of approximately 190 for hospitals and 60 for physicians.

CONCLUSION

In this national cohort, hospital and physician AF ablation procedural volumes were directly related to acute procedural success and inversely related to rates of MAE.

Procedure Volume and Outcomes With WATCHMAN Left Atrial Appendage Occlusion

BACKGROUND

Procedure volumes are associated with outcomes for many cardiovascular procedures, leading to guidelines on minimum volume thresholds for certain procedures; however, the volume-outcome relationship with left atrial appendage occlusion is poorly understood. As such, we sought to determine the relationship between hospital and physician volume and WATCHMAN left atrial appendage occlusion procedural success overall and with the new generation WATCHMAN FLX device.

METHODS

We performed an analysis of WATCHMAN procedures (January 2019 to October 2021) from the National Cardiovascular Data Registry LAAO Registry. Three-level hierarchical generalized linear models were used to assess the adjusted relationship between procedure volume and procedural success (device released with peridevice leak <5 mm, no in-hospital major adverse events).

RESULTS

Among 87 480 patients (76.2±8.0 years; 58.8% men; mean CHA2DS2-VASc score, 4.8±1.5) from 693 hospitals, the procedural success rate was 94.2%. With hospital volume Q4 (greatest volume) as the reference, the likelihood of procedural success was significantly less among Q1 (odds ratio [OR], 0.66 [CI, 0.57-0.77]) and Q2 (OR, 0.78 [CI, 0.69-0.90]) but not Q3 (OR, 0.95 [CI, 0.84-1.07]). With physician volume Q4 (greatest volume) as the reference, the likelihood of procedural success was significantly less among Q1 (OR, 0.72 [CI, 0.63-0.82]), Q2 (OR, 0.79 [CI, 0.71-0.89]), and Q3 (OR, 0.88 [CI, 0.79-0.97]). Among WATCHMAN FLX procedures, there was attenuation of the volume-outcome relationships, with statistically significant but modest absolute differences of only ≈1% across volume quartiles.

CONCLUSIONS

In this contemporary national analysis, greater hospital and physician WATCHMAN volumes were associated with increased procedure success. The WATCHMAN FLX transition was associated with increased procedural success and less heterogeneity in outcomes across volume quartiles. These findings indicate the importance of understanding the volume-outcome relationship for individual left atrial appendage occlusion devices.

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.

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.

Annual Case Volume and One-Year Mortality for Endovascular Treatment in Acute Ischemic Stroke

BACKGROUND

The association between endovascular treatment (EVT) case volume per hospital and clinical outcomes has been reported, but the exact volume threshold has not been determined. This study aimed to examine the case volume threshold in this context.

METHODS

National audit data on the quality of acute stroke care in patients admitted via emergency department, within 7 days of onset, in hospitals that treated ≥ 10 stroke cases during the audit period were analyzed. Ischemic stroke cases treated with EVT during the last three audits (2013, 2014, and 2016) were selected for the analysis. Annual EVT case volume per hospital was estimated and analyzed as a continuous and a categorical variable (in quartiles). The primary outcome measure was 1-year mortality as a surrogate of 3-month functional outcome. As post-hoc sensitivity analysis, replication of the study results was examined using the 2018 audit data.

RESULTS

We analyzed 1,746 ischemic stroke cases treated with EVT in 120 acute care hospitals. The median annual EVT case volume was 12.0 cases per hospital, and mortality rates at 1 month, 3 months, and 1 year were 12.7%, 16.6%, and 23.3%, respectively. Q3 and Q4 had 33% lower odds of 1-year mortality than Q1. Adjustments were made for predetermined confounders. Annual EVT case volume cut-off value for 1-year mortality was 15 cases per year (P < 0.02). The same cut-off value was replicated in the sensitivity analysis.

CONCLUSION

Annual EVT case volume was associated with 1-year mortality. The volume threshold per hospital was 15 cases per year.

Center Valve Preference and Outcomes of Transcatheter Aortic Valve Replacement: Insights From the AMTRAC Registry

BACKGROUND

Data on outcomes of transcatheter aortic valve replacement (TAVR) using balloon-expandable valves (BEVs) or self-expandable valves (SEVs) as well as the impact of center valve preference on these outcomes are limited.

OBJECTIVES

The aim of this study was to compare outcomes of TAVR procedures using third-generation BEVs and SEVs stratified by center valve preference.

METHODS

In a multicenter registry (n = 17), 13 centers exhibited valve preference (66.6%-90% of volume) and were included. Outcomes were compared between BEVs and SEVs stratified by center valve preference.

RESULTS

In total, 7,528 TAVR procedures (3,854 with SEVs and 3,674 with BEVs) were included. The mean age was 81 years, and the mean Society of Thoracic Surgeons score was 5.2. Baseline characteristics were similar between BEVs and SEVs. Need for pacemaker implantation was higher with SEVs at BEV- and SEV-dominant centers (17.8% vs 9.3% [P < 0.001] and 12.7% vs 10.0% [P = 0.036], respectively; HR: 1.51; P for interaction = 0.021), risk for cerebrovascular accident was higher with SEVs at BEV-dominant but not SEV-dominant centers (3.6% vs 1.1% [P < 0.001] and 2.2% vs 1.4% [P = 0.162]; HR: 2.08; P for interaction < 0.01). Aortic regurgitation greater than mild was more frequent with SEVs at BEV-dominant centers and similar with BEVs regardless of center dominance (5.2% vs 2.8% [P < 0.001] and 3.4% vs 3.7% [P = 0.504], respectively). Two-year mortality was higher with SEVs at BEV-dominant centers but not at SEV-dominant centers (21.9% vs 16.9% [P = 0.021] and 16.8% vs 16.5% [P = 0.642], respectively; HR: 1.20; P for interaction = 0.032).

CONCLUSIONS

Periprocedural outcomes, aortic regurgitation greater than mild, and 2-year mortality are worse when TAVR is performed using SEVs at BEV-dominant centers. Outcomes are similar regardless of valve type at SEV-dominant centers. The present results stress the need to account for this factor when comparing BEV and SEV outcomes. (The Aortic+Mitral Transcatheter [AMTRAC] Valve Registry; NCT04031274).

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.

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.

Nationwide Analysis of Endovascular Thrombectomy Provider Specialization for Acute Stroke

Background and Purpose:

Determine the extent of cerebrovascular expertise among the specialties of proceduralists providing endovascular thrombectomy (ET) for emergent large vessel occlusion stroke in the modern era of acute stroke among Medicare beneficiaries

Methods:

Retrospective cohort study using validated International Classification of Diseases, Tenth Revision , Clinical Modification codes to identify admissions with acute ischemic stroke and treatment with ET. We identified proceduralist specialty by linking the National Provider Identifier provided by Medicare to the specialty listed in the National Provider Identifier database, grouping into radiology, neurology, neurosurgery, other surgical, and internal medicine. We calculated the number of proceduralists and hospitals who performed ET, ET team specialty composition by hospital, and number of proceduralists who performed ET at multiple hospitals.

Results:

Forty-two percent (n=5612) of ET were performed by radiology-background proceduralists, with unclear knowledge of how many were cerebrovascular specialists. Neurosurgery- and neurology-background interventionalists performed fewer but substantial numbers of cases, accounting for 24% (n=3217) and 23% (n=3124) of total cases, respectively. ET teams included a neurology- or neurosurgery-background proceduralist at 65% (n=407) of hospitals that performed ET and included both in 26% (n=160) of teams.

Conclusions:

Almost two-thirds of ET teams nationwide include a neurology- or neurosurgery-background proceduralist and higher volume centers in urban areas were more likely to have neurology- or neurosurgery-background proceduralists with cerebrovascular expertise on their team. It is unclear how many radiology-background interventionalists are cerebrovascular specialists versus generalists. Significant work remains to be done to understand the impact of proceduralist specialty, training, and cerebrovascular expertise on ET outcomes.

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.

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.

The Relation between Volume and Outcome of Transcatheter and Surgical Aortic Valve Replacement: A Systematic Review and Meta-Analysis

Transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) are standard procedures for dealing with severe aortic stenosis patients. Researchers have not carried out a systematic review of the volume-outcome relationship in TAVR and SAVR. Our study is intended to address this problem. We systemically searched databases through MEDLINE, EMBASE, PUBMED, and the Cochrane Library up to September 2019. Two reviewers independently screened for the studies and evaluated bias. We used short-term mortality (in-hospital or 30-day mortality) as an outcome. A meta-analysis of TAVR with 115,596 patients ranging from 2005 to 2016 showed a result significantly in favor of high-volume hospitals (OR 0.43 (CI 0.36-0.51)). The subgroup of population period, region, data type, and cut-off value did not show any difference. A meta-analysis of SAVR comprising 418,384 patients ranging from 1994 to 2011 revealed that the OR of short-term mortality for a high-volume hospital compared with that of a low-volume hospital was 0.73 (CI 0.71, 0.74). No difference was observed in subgroups based on population period and cut-off. In conclusion, we found that short-term mortality was lower in high-volume hospitals for both TAVR and SAVR.

Contemporary Use and Trends in Unprotected Left Main Coronary Artery Percutaneous Coronary Intervention in the United States: An Analysis of the National Cardiovascular Data Registry Research to Practice Initiative

Importance

Recent data support percutaneous revascularization as an alternative to coronary artery bypass grafting in unprotected left main (ULM) coronary lesions. However, the relevance of these trials to current practice is unclear, as patterns and outcomes of ULM percutaneous coronary intervention (PCI) in contemporary US clinical practice are not well studied.

Objective

To define the current practice of ULM PCI and its outcomes and compare these with findings reported in clinical trials.

Design, Setting, and Participants

This cross-sectional multicenter analysis included data collected from 1662 institutions participating in the National Cardiovascular Data Registry (NCDR) CathPCI Registry between April 2009 and July 2016. Data were collected from 33 128 patients undergoing ULM PCI and 3 309 034 patients undergoing all other PCI. Data were analyzed from June 2017 to May 2018.

Main Outcomes and Measures

Patient and procedural characteristics and their temporal trends were compared between ULM PCI and all other PCI. In-hospital major adverse clinical events (ie, death, myocardial infarction, stroke, and emergent coronary artery bypass grafting) were compared using hierarchical logistic regression. Characteristics and outcomes were also compared against clinical trial cohorts.

Results

Of the 3 342 162 included patients, 2 223 570 (66.5%) were male, and the mean (SD) age was 64.2 (12.1) years. Unprotected left main PCI represented 1.0% (33 128 of 3 342 162) of all procedures, modestly increasing from 0.7% to 1.3% over time. The mean (SD) annualized ULM PCI volume was 0.5 (1.5) procedures for operators and 3.2 (6.1) procedures for facilities, with only 1808 of 10 971 operators (16.5%) and 892 of 1662 facilities (53.7%) performing an average of 1 or more ULM PCI annually. After adjustment, major adverse clinical events occurred more frequently with ULM PCI compared with all other PCI (odds ratio, 1.46; 95% CI, 1.39-1.53). Compared with clinical trial populations, patients in the CathPCI Registry were older with more comorbid conditions, and adverse events were more frequent.

Conclusions and Relevance

Use of ULM PCI has increased over time, but overall use remains low. These findings suggest that ULM PCI occurs infrequently in the United States and in an older and more comorbid population than that seen in clinical trials.

Association between Hospital volume of cardiopulmonary resuscitation for in-hospital cardiac arrest and survival to Hospital discharge

BACKGROUND

Prior studies have shown that hospital case volume is not associated with survival in patients with out-of-hospital cardiac arrest (OHCA). However, how case volume impact on survival for in-hospital cardiac arrest (IHCA) is unknown.

METHODS

We queried the National Inpatient Sample (NIS) in the U.S. 2005-2011 to identify cases in which in-hospital CPR was performed for IHCA. Restricted cubic spine was used to evaluate the association between hospital annual CPR volume and survival to hospital discharge.

RESULTS

Across more than 1000 hospitals in NIS, we identified 125,082 cases (mean age 67, 45% female) of IHCA for which CPR was performed over the study period. Median [Q1, Q3] case volume was 60 [34, 99]. Compared to those in the 1 st quartile of case volume, hospitals in the 4th quartile tends to have younger patients (mean = 66 vs 68 yrs), higher comorbidities (median Elixhauser score = 4 vs 3), and in low income areas (37 vs 30%). Overall, 23% of the patients survived to hospital discharge. There was a non-linear association between CPR volume and survival: a non-significant trend towards better survival was observed with increasing annual CPR volume that reached a plateau at 51-55 cases per year, after which survival began to drop and became significantly lower after 75 cases per year (p for non-linearity<0.001). Compared to those in first quartile of case volume, hospitals in 4^th quartile had higher length of stay (median = 8 vs 10 days, respectively) and higher rate of non-routine home discharge (64% vs 67%) among those who survived.

CONCLUSION

Unlike OHCA, low CPR volume is an indicator of good performing hospitals and increasing CPR case volume does not translate to improve survival for IHCA.

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.

Effect of the Number of Neurointerventionalists on Off-Hour Endovascular Therapy for Acute Ischemic Stroke Within 12 Hours of Symptom Onset

Background

Off‐hour presentation can affect treatment delay and clinical outcomes in endovascular therapy (EVT) for acute ischemic stroke. We aimed to examine the treatment delays and clinical outcomes of EVT between on‐ and off‐hour admission and to evaluate the effect of hospital procedure volume and the number of neurointerventionalists on off‐hour EVT.

Methods and Results

From a multicenter registry, we identified patients who were treated with EVT within 12 hours of symptom. Annual hospital procedure volume was divided as low (<30), medium (30–60), and high (>60). The effect of the number of neurointerventionalists and annual hospital procedure volume on clinical outcome was estimated by the generalized estimation equation. Of the 31 133 stroke patients, 1564 patients met the eligibility criteria (mean age: 69±12 years; median baseline National Institutes of Health stroke scale score, 15 [interquartile range, 10–19]). Of 1564 patients, 893 (57.1%) arrived during off‐hour. The off‐hour patients had greater median door‐to‐puncture time (110  versus 95 minutes; P<0.001) compared with on‐hour patients. Despite the treatment delay, the functional outcome at 3 months did not differ between off‐ and on‐hour (odds ratio with 95% CI for 3‐month modified Rankin Scale 0–2, 0.99 [0.78–1.25]; P=0.90). The presence of three neurointerventionalists was significantly associated with favorable outcomes at 3 months during on‐ and off‐hour (2.07 [1.53–2.81]; P<0.001). The association was not observed for annual hospital procedural volume and the functional outcomes.

Conclusions

The number of neurointerventionalists was more crucial to effective around‐the‐clock EVT for acute stroke patients than hospital procedural volume.

Procedural Volume and Outcomes for Transcatheter Aortic-Valve Replacement

BACKGROUND

During the introduction of transcatheter aortic-valve replacement (TAVR) in the United States, requirements regarding procedural volume were mandated by the Centers for Medicare and Medicaid Services as a condition of reimbursement. A better understanding of the relationship between hospital volume of TAVR procedures and patient outcomes could inform policy decisions.

METHODS

We analyzed data from the Transcatheter Valve Therapy Registry regarding procedural volumes and outcomes from 2015 through 2017. The primary analyses examined the association between hospital procedural volume as a continuous variable and risk-adjusted mortality at 30 days after transfemoral TAVR. Secondary analysis included risk-adjusted mortality according to quartile of hospital procedural volume. A sensitivity analysis was performed after exclusion of the first 12 months of transfemoral TAVR procedures at each hospital.

RESULTS

Of 113,662 TAVR procedures performed at 555 hospitals by 2960 operators, 96,256 (84.7%) involved a transfemoral approach. There was a significant inverse association between annualized volume of transfemoral TAVR procedures and mortality. Adjusted 30-day mortality was higher and more variable at hospitals in the lowest-volume quartile (3.19%; 95% confidence interval [CI], 2.78 to 3.67) than at hospitals in the highest-volume quartile (2.66%; 95% CI, 2.48 to 2.85) (odds ratio, 1.21; P = 0.02). The difference in adjusted mortality between a mean annualized volume of 27 procedures in the lowest-volume quartile and 143 procedures in the highest-volume quartile was a relative reduction of 19.45% (95% CI, 8.63 to 30.26). After the exclusion of the first 12 months of TAVR procedures at each hospital, 30-day mortality remained higher in the lowest-volume quartile than in the highest-volume quartile (3.10% vs. 2.61%; odds ratio, 1.19; 95% CI, 1.01 to 1.40).

CONCLUSIONS

An inverse volume-mortality association was observed for transfemoral TAVR procedures from 2015 through 2017. Mortality at 30 days was higher and more variable at hospitals with a low procedural volume than at hospitals with a high procedural volume. (Funded by the American College of Cardiology Foundation National Cardiovascular Data Registry and the Society of Thoracic Surgeons.).

Temporal trends in the practice of the transradial approach for percutaneous coronary intervention in a large tertiary center

OBJECTIVE

The transradial approach (TRA) has increasingly been adopted for the use of percutaneous coronary interventions (PCI), with reported clinical benefits. Little is known regarding the change in outcomes over time.

PATIENTS AND METHODS

From our large single-center PCI registry, we have analyzed 15 429 patients in two periods - 2008-2012 (period 1) and 2013-2017 (period 2). We examined the proportions of use of TRA, the influence on in-hospital outcomes, and adjusted long-term effects.

RESULTS

The rate of TRA rose from 15.9% in period 1 to 69.1% in period 2, including in specific situations such as acute coronary syndrome, chronic total occlusion, bifurcation, calcified lesions, and unprotected left main PCI. In-hospital rates of bleeding were lower for TRA versus transfemoral artery (1.8 vs. 5.1%, overall, P < 0.001), as were rates of additional bleeding events in the following 12 months (1.3 vs. 2.4%, P < 0.001). Following multivariate analysis, use of TRA was associated with a lower 30-day and 4-year rate of the composite outcomes of death, myocardial infarction, target vessel revascularization, or coronary artery bypass surgery [at 4 years, hazard ratio (HR) = 0.86; 95% confidence interval (CI): 0.77-0.96; P = 0.007, during period 1 and HR = 0.62; 95% CI 0.55-0.7; P < 0.0001 during period 2]. Interaction analysis showed a stronger effect at the latter period (HR = 0.69, 95% CI: 0.59-0.81, P < 0.001).

CONCLUSION

Over a decade of follow-up, TRA has gained acceptance for different PCI scenarios, including complex patients - a course which is associated with consistent short and long-term clinical benefits.

The Impact of Formal Training and Certification on the Relationship Between Volume and Outcomes in Percutaneous Coronary Interventions

BACKGROUND

Little data are available on the impact of formal training and certification on the relationship between volumes and outcome in percutaneous coronary interventions (PCIs).The objective of this report is to study the relationship between PCI volume and outcome for a formally trained interventional cardiologist who is certified by the American Board on Internal Medicine - Interventional Cardiology subspecialty board.

METHODS

The operator witnessed 3 different PCI volumes/yr over a 15-year practice period (2000-2014): <50 PCI/yr (years 2000-2006; n = 179), 50-100 PCI/yr (years 2007-2010; n = 256), and >100 PCI/yr (years 2011-2014; n = 427). Angiographic and procedural success rates were compared between the 3 volume groups, as well as in-hospital cardiovascular events (death, recurrent myocardial infarction, repeat PCI, stroke, or coronary artery bypass surgery).

RESULTS

The in-hospital mortality rate throughout the study period was 0.8% and was not statistically significant among the 3 volume groups. There was also no significant difference among the 3 groups with respect to recurrent myocardial infarction or repeat PCI. There was a slightly higher rate of same-stay elective coronary artery bypass grafting in the early low-volume period compared with the other 2 groups (2.2% vs. 0.8% vs. 0.2%; P = 0.04). The overall angiographic and procedural success rates were 97.3% and 96.5%, and they were not significantly different among the 3 groups.

CONCLUSIONS

Our study shows that the angiographic and procedural success rates of PCI, as well as the in-hospital mortality, do not seem to be dependent on the annual volume for formally trained and certified interventional cardiologists.

Relation of Bleeding Events to Mortality in Patients With ST-Segment Elevation Myocardial Infarction Treated by Percutaneous Coronary Intervention (a DANAMI-3 Substudy)

Bleeding events in relation to treatment of ST-segment elevation myocardial infarction (STEMI) have previously been associated with mortality. In this study, we investigated the incidence and prognosis of, and variables associated with serious bleedings within 30 days after primary percutaneous coronary intervention in patients from The Third Danish Study of Optimal Acute Treatment of Patients with ST-Segment Elevation Myocardial Infarction (DANAMI-3) (n = 2,217). Hospital charts were read within 30 days postadmission to assess bleeding events using thrombolysis in myocardial infarction (TIMI) and Bleeding Academic Research Consortium criteria. TIMI minor/major bleeding (TMMB) occurred in 59 patients (2.7%). Variables associated with TMMB were female gender (hazard ratio [HR] 3.9, 95% confidence interval [CI] 2.2 to 6.7, p <0.0001), symptom-to-catheterization time >3 hours (HR 1.9, 95% CI 1.1 to 3.3, p = 0.02), use of glycoprotein IIb/IIIa inhibitor (HR 2.1, 95% CI 1.2 to 3.7, p = 0.01), and increasing S-creatinine (HR 1.1, 95% CI 1.0 to 1.2, p = 0.001). Undergoing 2 in-hospital procedures were not associated with increased risk of TMMB. TMMB was strongly associated with 30-day mortality in multivariable analysis (HR 4.8, 95% CI 2.2 to 10.4, p <0.0001) but not with mortality days 31 to 365. When excluding fatal bleedings from the analysis, a TMMB was no longer associated with 30-day mortality. In conclusion, we found that in a contemporary STEMI-population, the incidence of 30-day TMMB was low. A TMMB was strongly associated with 30-day mortality but not with mortality days 31 to 365. If patients survived a serious bleeding, their short- and long-term prognoses were not affected.

Stent and Dual Antiplatelet Therapy Duration Comparisons in the Setting of a Multicenter Randomized Controlled Trial: Can the Operator Experience Affect the Study Results?

Background

Operator experience influences outcomes after percutaneous coronary intervention, but this association in the controlled setting of a randomized, clinical trial is unclear.

Methods and Results

We investigated operator‐related outcomes (30‐day and 2‐year efficacy and safety end points) among patients undergoing percutaneous coronary intervention and randomized to different dual antiplatelet therapy durations and stent types. A total of 2003 patients were analyzed, and 7 operator groups were compared. The majority of preprocedural and postprocedural characteristics were imbalanced. The primary end point of the study, the composite of death, myocardial infarction, or cerebrovascular accidents, did not differ among operators at 30 days or 2 years. There were no significant differences also for all other individual and composite end points analyzed at 30 days and 2 years, except for 2‐year stent thrombosis (P=0.048) and bleeding events (P=0.022 for Bleeding Academic Research Consortium type 2, 3, or 5). Adjusted comparisons for the main end points showed slight differences among operators at 30 days, but not at 2 years. There was no interaction of operator with dual antiplatelet therapy duration (P=0.112) or stent type (P=0.300). Results remained entirely consistent when operators were stratified by their experience.

Conclusions

There was a weak signal of heterogeneity across study operators for the 30‐day, but not the 2‐year, main study outcomes. No clear effect of operator or operator experience was observed for the comparative efficacy and safety profile of the randomized stent types or dual antiplatelet therapy duration regimens.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00611286.

Total Center Percutaneous Coronary Intervention Volume and 30-Day Mortality: A Contemporary National Cohort Study of 427 467 Elective, Urgent, and Emergency Cases

BACKGROUND

The relationship between procedural volume and prognosis after percutaneous coronary intervention (PCI) remains uncertain, with some studies finding in favor of an inverse association and some against. This UK study provides a contemporary reassessment in one of the few countries in the world with a nationally representative PCI registry.

METHODS AND RESULTS

A nationwide cohort study was performed using the national British Cardiovascular Intervention Society registry. All adult patients undergoing PCI in 93 English and Welsh NHS hospitals between 2007 and 2013 were analyzed using hierarchical modeling with adjustment for patient risk. Of 427 467 procedures (22.0% primary PCI) in 93 hospitals, 30-day mortality was 1.9% (4.8% primary PCI). 87.1% of centers undertook between 200 and 2000 procedures annually. Case mix varied with center volume. In centers with 200 to 399 PCI cases per year, a smaller proportion were PCI for ST-segment-elevation myocardial infarction (8.4%) than in centers with 1500 to 1999 PCI cases per year (24.2%), but proportionally more were for ST-segment-elevation myocardial infarction with cardiogenic shock (8.4% versus 4.3%). For the overall PCI cohort, after risk adjustment, there was no significant evidence of worse, or better, outcomes in lower volume centers from our own study, or in combination with results from other studies. For primary PCI, there was also no evidence for increased or decreased mortality in lower volume centers.

CONCLUSIONS

After adjustment for differences in case mix and clinical presentation, this study supports the conclusion of no trend for increased mortality in lower volume centers for PCI in the UK healthcare system.

CLINICAL TRIAL REGISTRATION

https://www.clinicaltrials.gov. Unique identifier: NCT02184949.

When high-volume PCI operators in high-volume hospitals move to lower volume hospitals-Do they still maintain high volume and quality of outcomes?

OBJECTIVES

The aim of this quasi-experimental study was to examine whether high-volume percutaneous coronary intervention (PCI) operators still maintain high volume and quality of outcomes when they moved to lower volume hospitals.

BACKGROUND

Systematic reviews have indicated that high-volume PCI operators and hospitals have higher quality outcomes. However, little is known on whether high PCI volume and high quality outcomes are mainly due to operator characteristics (i.e., skill and experience) and is portable across organizations or whether it is due to hospital characteristics (i.e., equipment, team, and management system) and is less portable.

METHODS

We used Taiwan National Health Insurance claims data 2000-2012 to identify 98 high-volume PCI operators, 10 of whom moved from one hospital to another during the study period. We compared the PCI volume, risk-adjusted mortality ratio, and major adverse cardiovascular event (MACE) ratio before and after moving.

RESULTS

Of the 10 high-volume operators who moved, 6 moved from high- to moderate- or low-volume hospitals, with median annual PCI volumes (interquartile range) of 130 (117-165) in prior hospitals and 54 (46-84) in subsequent hospitals (the hospital the operator moved to), and the remaining 4 moved from high to high-volume hospitals, with median annual PCI volumes (interquartile range) of 151 (133-162) in prior hospitals and 193 (178-239) in subsequent hospitals. No significant differences were observed in the risk-adjusted mortality ratios and MACE ratios between high-volume operators and matched controls before and after moving.

CONCLUSIONS

High-volume operators cannot maintain high volume when they moved from high to moderate or low-volume hospitals; however, the quality of care is maintained. High PCI volume and high-quality outcomes are less portable and more hospital bound.

Multicentre analysis of current ST-elevation myocardial infarction acute care pathways

BACKGROUND

Rapid reperfusion with percutaneous coronary intervention (PCI) is vital for patients with ST segment elevation myocardial infarction (STEMI). However, the guideline-recommended time targets are regularly exceeded. The goal of this study was to gain insight into how Dutch PCI centres try to achieve these time targets by comparing their care processes with one another and with the European guideline-recommended process. In addition, accelerating factors perceived by care providers were identified.

METHODS

In this multiple case study, interviews with STEMI care providers were conducted, transcribed and used to create process descriptions per centre. Analyses consisted of within-case and between-case analyses of the processes. Accelerating factors were identified by means of open and axial coding.

RESULTS

In total, 28 interviews were conducted in six PCI centres. The centres differed from the guideline-recommended process on, for example, additional, unavoidable patient routings and monitoring delays, and from one another on the communication of diagnostic information (eg, transmitting all, only ambiguous or no ECGs) and catheterisation room preparation. These differences indicated diverging choices to maintain a balance between speed and diagnostic accuracy. Factors perceived by care providers as accelerating the process included trust in the tentative diagnosis, and avoiding unnecessary intercaregiver consultations. The combination of processes and accelerating factors were summarised in a model.

CONCLUSIONS

Numerous differences in processes between PCI centres were identified. Several time-saving strategies were applied by PCI centres, however, in different configurations. To further improve the care for patients with STEMI, best practices can be shared between centres and countries.

Influence of hospital volume on nephrectomy mortality and complications: a systematic review and meta-analysis stratified by surgical type

OBJECTIVES

The provision of complex surgery is increasingly centralised to high-volume (HV) specialist hospitals. Evidence to support nephrectomy centralisation however has been inconsistent. We conducted a systematic review and meta-analysis to determine the association between hospital case volumes and perioperative outcomes in radical nephrectomy, partial nephrectomy and nephrectomy with venous thrombectomy.

METHODS

Medline, Embase and the Cochrane Library were searched for relevant studies published between 1990 and 2016. Pooled effect estimates for nephrectomy mortality and complications were calculated for each nephrectomy type using the DerSimonian and Laird random-effects model. Sensitivity analyses were performed to examine the effects of heterogeneity on the pooled effect estimates by excluding studies with the heaviest weighting, lowest methodological score and most likely to introduce bias from misclassification of standardised hospital volume.

RESULTS

Some 226 372 patients from 16 publications were included in our review and meta-analysis. Considerable between-study heterogeneity was noted and only a few reported volume-outcome relationships specifically in partial nephrectomy or nephrectomy with venous thrombectomy.HV hospitals were correlated with a 26% and 52% reduction in mortality for radical nephrectomy (OR 0.74, 95% CI 0.61 to 0.90, p<0.01) and nephrectomy with venous thrombectomy (OR 0.48, 95% CI 0.29 to 0.81, p<0.01), respectively. In addition, radical nephrectomy in HV hospitals was associated with an 18% reduction in complications (OR 0.82, 95% CI 0.73 to 0.92, p<0.01). No significant volume-outcome relationship in mortality (OR 0.84, 95% CI 0.31 to 2.26, p=0.73) or complications (OR 0.85, 95% CI 0.55 to 1.30, p=0.44) was observed for partial nephrectomy.

CONCLUSIONS

Our findings suggest that patients undergoing radical nephrectomy have improved outcomes when treated by HV hospitals. Evidence of this in partial nephrectomy and nephrectomy with venous thrombectomy is however not yet clear and could be secondary to the low number of studies included and the small patient number in our analyses. Further investigation is warranted to establish the full potential of nephrectomy centralisation particularly as existing evidence is of low quality with significant heterogeneity.

Comparison of the treatment practice and hospitalization cost of percutaneous coronary intervention between a teaching hospital and a general hospital in Malaysia: A cross sectional study

Introduction

The increasing disease burden of coronary artery disease (CAD) calls for sustainable cardiac service. Teaching hospitals and general hospitals in Malaysia are main providers of percutaneous coronary intervention (PCI), a common treatment for CAD. Few studies have analyzed the contemporary data on local cardiac facilities. Service expansion and budget allocation require cost evidence from various providers. We aim to compare the patient characteristics, procedural outcomes, and cost profile between a teaching hospital (TH) and a general hospital (GH).

Methods

This cross-sectional study was conducted from the healthcare providers’ perspective from January 1^st to June 30^th 2014. TH is a university teaching hospital in the capital city, while GH is a state-level general hospital. Both are government-funded cardiac referral centers. Clinical data was extracted from a national cardiac registry. Cost data was collected using mixed method of top-down and bottom-up approaches. Total hospitalization cost per PCI patient was summed up from the costs of ward admission and cardiac catheterization laboratory utilization. Clinical characteristics were compared with chi-square and independent t-test, while hospitalization length and cost were analyzed using Mann-Whitney test.

Results

The mean hospitalization cost was RM 12,117 (USD 3,366) at GH and RM 16,289 (USD 4,525) at TH. The higher cost at TH can be attributed to worse patients’ comorbidities and cardiac status. In contrast, GH recorded a lower mean length of stay as more patients had same-day discharge, resulting in 29% reduction in mean cost of admission compared to TH. For both hospitals, PCI consumables accounted for the biggest proportion of total cost.

Conclusions

The high PCI consumables cost highlighted the importance of cost-effective purchasing mechanism. Findings on the heterogeneity of the patients, treatment practice and hospitalization cost between TH and GH are vital for formulation of cost-saving strategies to ensure sustainable and equitable cardiac service in Malaysia.

Is There a Relationship of Operator and Center Volume With Access Site-Related Outcomes? An Analysis From the British Cardiovascular Intervention Society

BACKGROUND

Transradial access is associated with reduced access site-related bleeding complications and mortality post percutaneous coronary intervention. The objective of this study is to examine the relationship between access site practice and clinical outcomes and how this may be influenced by operator and center experience/expertise.

METHODS AND RESULTS

The influence of operator and center experience/expertise was studied on 30-day mortality, in-hospital major adverse cardiovascular events (a composite of in-hospital mortality and in-hospital myocardial infarction and target vessel revascularization) and in-hospital major bleeding based on access site adopted (radial versus femoral). Operator/center experience/expertise were defined by both total volume and transradial access proportion. A total of 164 395 procedures between 2012 and 2013 in the National Health Service in England and Wales were analyzed. After case-mix adjustment, transradial access was associated with an average odds reduction of 39% for 30-day mortality compared with transfemoral access (odds ratio, 0.61; 95% confidence interval, 0.55-0.68; P<0.001). The magnitude of this risk reduction was modified by increases in total procedural volume and radial proportion at the operator level (odds ratio reduction of 11% per 100 extra procedures, 95% confidence interval, 3%-19%; odds ratio reduction of 6% per 10%-point increase in radial proportion, 95% confidence interval, 1%-11%) with no significant impact of operator radial volume, center total volume, center radial volume, and center radial proportion.

CONCLUSIONS

The lower mortality associated with transradial access adoption relates to both the total procedural volume and the proportion of procedures undertaken radially by operator, with operators undertaking the greatest proportion of their procedures radially having the largest relative reduction in mortality risk.

Percutaneous Coronary Intervention: Relationship Between Procedural Volume and Outcomes

Percutaneous coronary intervention (PCI) is an integral treatment modality for acute coronary syndromes (ACS) as well as chronic stable coronary artery disease (CAD) not responsive to optimal medical therapy. This coupled with studies on the feasibility and safety of performing PCI in centers without on-site surgical backup led to widespread growth of PCI centers. However, this has been accompanied by a recent steep decline in the volume of PCIs at both the operator and hospital level, which raises concerns regarding minimal procedural volumes required to maintain necessary skills and favorable clinical outcomes. The 2011 ACC/AHA/SCAI competency statement required PCI be performed by operators with a minimal procedural volume of >75 PCIs annually at high-volume centers with >400 PCIs per year, a number which was relaxed in the 2013 ACC/AHA/SCAI update to >50 PCIs/operator/year in hospitals with >200 PCIs annually to coincide with reduction in national PCI volume. Recent data suggests that many hospitals do not meet these thresholds. We review data on the importance of volume as a vital quality metric at both an operator and hospital level in determining procedural outcomes following PCI.

Relationship between surgeon volume and outcomes: a systematic review of systematic reviews

BACKGROUND

The surgeon volume-outcome relationship has been discussed for many years and its existence or nonexistence is of importance for various reasons. A lot of empirical work has been published on it. We aimed to summarize systematic reviews in order to present current evidence.

METHODS

Medline, Embase, Cochrane database of systematic reviews (CDSR), and health technology assessment websites were searched up to October 2015 for systematic reviews on the surgeon volume-outcome relationship. Reviews were critically appraised, and results were extracted and synthesized by type of surgical procedure/condition.

RESULTS

Thirty-two reviews reporting on 15 surgical procedures/conditions were included. Methodological quality of included systematic reviews assessed with the assessment of multiple systematic reviews (AMSTAR) was generally moderate to high albeit included literature partly neglected considering methodological issues specific to volume-outcome relationship. Most reviews tend to support the presence of a surgeon volume-outcome relationship. This is most clear-cut in colorectal cancer, bariatric surgery, and breast cancer where reviews of high quality show large effects.

CONCLUSIONS

When taking into account its limitations, this overview can serve as an informational basis for decision makers. Our results seem to support a positive volume-outcome relationship for most procedures/conditions. However, forthcoming reviews should pay more attention to methodology specific to volume-outcome relationship. Due to the lack of information, any numerical recommendations for minimum volume thresholds are not possible. Further research is needed for this issue.

ST Elevation Myocardial Infarction Mortality Among Patients With Liver Cirrhosis: A Nationwide Analysis Across a Decade

BACKGROUND

Mortality from ST elevation myocardial infarction (STEMI) is decreasing nationwide, but no report to date examined STEMI mortality among patients with cirrhosis.

GOALS

Determine mortality rates and investigate possible disparities in cardiovascular interventions for patients with and without cirrhosis admitted with STEMI across a decade using a national database.

STUDY

We included all urgent/emergent admissions with STEMI to acute care hospitals across the United States in 1999 and 2009. Exclusion criteria were age less than 18 years or prior liver transplantation. Confounders were accounted for using multivariable regression analyses.

RESULTS

A total of 325,857 and 182,491 patients with STEMI were included in 1999 and 2009, respectively, 741 and 541 of whom had cirrhosis, respectively. In-hospital mortality rate was 31% and 11% for patients with and without cirrhosis in 1999, and 17% and 9% in 2009. The adjusted mortality odds ratio was 2.54 (1.52 to 4.24) in 1999 and 1.45 (0.73 to 2.86) in 2009. Stent placement rate was 11% and 26% for patients with and without cirrhosis in 1999, and increased to 47% and 61% in 2009, respectively. Thrombolytic medication injection rate was 3% and 10% for patients with and without cirrhosis in 1999, and 0% and 2% in 2009, respectively. Coronary artery bypass graft surgery rate was 3% and 9% for patients with and without cirrhosis in 1999, and was 6% and 7% in 2009, respectively.

CONCLUSIONS

STEMI mortality in patients with cirrhosis is higher compared with patients without cirrhosis. However, this mortality difference declined from 1999 to 2009, likely because of higher coronary artery stent utilization for patients with cirrhosis.

Effectiveness of regionalized systems for stroke and myocardial infarction

BACKGROUND

Acute ischemic stroke (AIS) and ST-segment elevation myocardial infarction (STEMI) are ischemic emergencies. Guidelines recommend care delivery within formally regionalized systems of care at designated centers, with bypass of nearby centers of lesser or no designation. We review the evidence of the effectiveness of regionalized systems in AIS and STEMI.

METHODS

Literature was searched using terms corresponding to designation of AIS and STEMI systems and from 2010 to the present. Inclusion criteria included report of an outcome on any dependent variable mentioned in the rationale for regionalization in the guidelines and an independent variable comparing care to a non- or pre-regionalized system. Designation was defined in the AIS case as certification by the Joint Commission as either a primary (PSC) or comprehensive (CSC) stroke center. In the STEMI case, the search was conducted linking "regionalization" and "myocardial infarction" or citation as a model system by any American Heart Association statement.

RESULTS

For AIS, 17 publications met these criteria and were selected for review. In the STEMI case, four publications met these criteria; the search was therefore expanded by relaxing the criteria to include any historical or anecdotal comparison to a pre- or nonregionalized state. The final yield was nine papers from six systems.

CONCLUSION

Although regionalized care results in enhanced process and reduced unadjusted rates of disparity in access and adverse outcomes, these differences tend to become nonsignificant when adjusted for delayed presentation and hospital arrival by means other than emergency medical services. The benefits of regionalized care occur along with a temporal trend of improvement due to uptake of quality initiatives and guideline recommendations by all systems regardless of designation. Further research is justified with a randomized registry or cluster randomized design to support or refute recommendations that regionalization should be the standard of care.