Relationship between coronary angioplasty laboratory volume and outcomes after hospital discharge

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.

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.

A Systematic Review and Meta-Analysis of the Relationship Between Hospital Volume and the Outcomes of Percutaneous Coronary Intervention

Previous reviews have suggested that hospital volume is inversely related to in-hospital mortality. However, percutaneous coronary intervention (PCI) practices have changed substantially in recent years, and whether this relationship persists remains controversial.A systematic search was performed using PubMed, Embase, and the Cochrane Library to identify studies that describe the effect of hospital volume on the outcomes of PCI. Critical appraisals of the methodological quality and the risk of bias were conducted independently by 2 authors. Fourteen of 96 potentiality relevant articles were included in the analysis. Twelve of the articles described the relationship between hospital volume and mortality and included data regarding odds ratios (ORs); 3 studies described the relationship between hospital volume and long-term survival, and only 1 study included data regarding hazard ratios (HRs). A meta-analysis of postoperative mortality was performed using a random effects model, and the pooled effect estimate was significantly in favor of high volume providers (OR: 0.79; 95% confidence interval [CI], 0.72-0.86; P < 0.001). A systematic review of long-term survival was performed, and a trend toward better long-term survival in high volume hospitals was observed.This meta-analysis only included studies published after 2006 and revealed that postoperative mortality following PCI correlates significantly and inversely with hospital volume. However, the magnitude of the effect of volume on long-term survival is difficult to assess. Additional research is necessary to confirm our findings and to elucidate the mechanism underlying the volume-outcome relationship.

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

BACKGROUND

The relationship between operator or institutional volume and outcomes among patients undergoing percutaneous coronary interventions (PCI) is unclear.

METHODS AND RESULTS

Cross-sectional study based on the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample between 2005 to 2009. Subjects were identified by International Classification of Diseases, 9(th) Revision, Clinical Modification procedure code, 36.06 and 36.07. Annual operator and institutional volumes were calculated using unique identification numbers and then divided into quartiles. Three-level hierarchical multivariate mixed models were created. The primary outcome was in-hospital mortality; secondary outcome was a composite of in-hospital mortality and peri-procedural complications. A total of 457,498 PCIs were identified representing a total of 2,243,209 PCIs performed in the United States during the study period. In-hospital, all-cause mortality was 1.08%, and the overall complication rate was 7.10%. The primary and secondary outcomes of procedures performed by operators in 4(th) [annual procedural volume; primary and secondary outcomes] [>100; 0.59% and 5.51%], 3(rd) [45-100; 0.87% and 6.40%], and 2(nd) quartile [16-44; 1.15% and 7.75%] were significantly less (P<0.001) when compared with those by operators in the 1(st) quartile [≤15; 1.68% and 10.91%]. Spline analysis also showed significant operator and institutional volume outcome relationship. Similarly operators in the higher quartiles witnessed a significant reduction in length of hospital stay and cost of hospitalization (P<0.001).

CONCLUSIONS

Overall in-hospital mortality after PCI was low. An increase in operator and institutional volume of PCI was found to be associated with a decrease in adverse outcomes, length of hospital stay, and cost of hospitalization.

The volume-outcome relationship of percutaneous coronary intervention: can current procedure volume minimums be applied to a developing country?

OBJECTIVES

A minimum percutaneous coronary intervention (PCI) hospital volume of 400 cases per year is recommended by the American College of Cardiology/American Heart Association (ACC/AHA). However, it is unclear whether this minimum value standard applies to non-Western developing countries, such as Taiwan. The aim of this study was to assess the application in Taiwan of current ACC/AHA practice guidelines for minimum hospital PCI volume.

METHODS

Using the 2003 Taiwan National Health Insurance Research Database and the Cause of Death Data File, we analyzed and compared the risk of 30-day mortality for patients (n = 12369) treated at low- (< 200 cases per year), medium- (200-399 cases per year), and high- (> or = 400 cases per year) PCI volume hospitals. A multivariable logistic regression using generalized estimating equations was conducted to assess the independent association of hospital PCI volume and patient 30-day mortality.

RESULTS

Crude 30-day mortality rates among low-, medium-, and high-PCI volume hospitals were 3.10%, 2.82%, and 1.80%, respectively. Patients treated at low-PCI volume hospitals had 1.54 (95% CI, 1.17-2.02) times higher odds of 30-day mortality than those treated at high-PCI volume hospitals after adjusting for other factors. The adjusted odds ratio between medium- and high-volume hospitals did not reach statistical significance (odds ratio 1.33, 95% CI 0.91-1.56).

CONCLUSIONS

Though greater, the adjusted odds of 30-day mortality for patients undergoing PCI at medium-volume hospitals was not significantly different from those of patients treated at high-volume hospitals. This suggests that current ACC/AHA PCI hospital volume minimums may need to be reevaluated in non-Western countries such as Taiwan.

The impact of percutaneous coronary interventions on outcomes for acute myocardial infarction in Pennsylvania

This research estimates the benefits associated with percutaneous coronary interventions (PCIs) for patients with acute myocardial infarction (AMI) treated at hospitals in Pennsylvania. We studied 31 351 patients with AMI in Pennsylvania during the year 2000, including 10 170 who received PCI. Univariate comparisons between groups were made using chi2 tests for categorical outcomes and Student's t tests for continuous outcomes. A logit model for proportions was used to model the relationship between mortality and the proportion of AMI patients who received PCI. The mortality rate for patients undergoing PCI was significantly lower than for those being treated medically (1.4% vs 15.8%, P<.0001). Furthermore, significant survival benefits associated with PCI persisted when patients were stratified by age, sex, type of infarction, and severity at admission. At the hospital level, higher rates of PCI were associated with a significantly lower overall mortality rate among patients with AMI (P<.0001).

Gender disparities in percutaneous coronary interventions for acute myocardial infarction in Pennsylvania

BACKGROUND

It has been shown that women are at greater risk than men of not receiving screening and treatment services for coronary heart disease. The purpose of this research was to determine whether there were gender disparities in the use of percutaneous coronary interventions (PCI) in the treatment of acute myocardial infarction (AMI) in Pennsylvania in 2000 and, if so, whether outcomes were affected.

METHODS

Data included 10,170 patients treated with PCI and 21,181 patients medically managed in Pennsylvania hospitals. Multivariate analyses were performed using logistic regression to estimate the impact of gender on PCI. In addition, we performed retrospective matching on propensity scores to compare outcomes for women who were treated with PCI to comparable groups of women and men.

RESULTS

After controlling for age, race/ethnicity, severity at admission, location of infarct, and source of admission, women had 24% lower odds than men of receiving PCI (P<0.0001). In a propensity score-matched sample of 3023 women who received PCI and 3023 women who did not, women who received PCI were significantly less likely to die (2.3% vs. 10.4%, P<0.0001). In a second propensity score-matched sample of 3329 women and 3329 similar men who received PCI, the difference in mortality was not statistically significant (1.59% vs. 1.92%, P=0.39).

CONCLUSIONS

These results suggest that the morbidity and mortality associated with AMI in women could be reduced by increased use of PCI and that more women admitted for AMI should receive consideration for PCI.

Percutaneous coronary intervention: recommendations for good practice and training

Cardiologists undertaking percutaneous coronary intervention (PCI) are excited by the combination of patient and physician satisfaction and technological advance occurring on the background of the necessary manual dexterity. Progress and applicability of percutaneous techniques since their inception in 1977 have been remarkable; a sound evidence base coupled with the enthusiasm and ingenuity of the medical device industry has resulted in a sea change in the treatment of coronary heart disease (CHD), which continues to evolve at breakneck speed. This is the third set of guidelines produced by the British Cardiovascular Intervention Society and the British Cardiac Society. Following the last set of guidelines published in 2000, we have seen PCI activity in the UK increase from 33,652 to 62,780 (87% in four years) such that the PCI to coronary artery bypass grafting ratio has increased to 2.5:1. The impact of drug eluting stents has been profound, and the Department of Health is investigating the feasibility of primary PCI for acute myocardial infarction. Nevertheless, the changes in the structure of National Health Service funding are likely to focus our attention on cost effective treatments and will require physician engagement and sensitive handling if we are to continue the rapid and appropriate growth in our chosen field. It is important with this burgeoning development now occurring on a broad front (in both regional centres and district general hospitals) that we maintain our vigilance on audit and outcome measures so that standards are maintained for both operators and institutions alike. This set of guidelines includes new sections on training, informed consent, and a core evidence base, which we hope you will find useful and informative.

The lack of a simple relation between physician's percutaneous coronary intervention volume and outcomes in the era of coronary stenting: a two-centre experience

The 2001 ACC/AHA guidelines recommend that percutaneous coronary intervention (PCI) operators perform at least 75 procedures per year to maintain their competency. We performed a post hoc analysis of prospectively gathered PCI data, in the current era of ubiquitous stent use, at two tertiary cardiac care centres. Operators were assigned to a low (<50 cases per year), intermediate (50-74 cases per year) or high volume (>or=75 cases per year) group. Complications evaluated were death, myocardial infarction, coronary perforation, emergent coronary artery bypass surgery and pericardial tamponade. Between 2000 and 2002, 51 operators performed 6,510 PCIs. Stents were used in 79% of cases. Major complications occurred in 0.45% (7/1,572 cases) for the low-volume group, 1.1% in the intermediate-volume group (16/1,438 cases) and 0.86% (30/3,500 cases) for the high-volume group. After adjusting for baseline factors, low- and intermediate-volume operators were not significantly associated with major complications. This study questions the relationship between operator volume and PCI complications in the current era.

Volume-Outcome Relationships for Percutaneous Coronary Interventions in the Stent Era

Background— Most studies that are the basis of recommended volume thresholds for percutaneous coronary interventions (PCIs) predate the routine use of stent placement.

Methods and Results— Data from New York’s Percutaneous Coronary Interventions Reporting System in 1998 to 2000 (n=107 713) were used to examine the impact of annual hospital volume and annual operator volume on in-hospital mortality, same-day coronary artery bypass graft (CABG) surgery, and same-stay CABG surgery after adjustment for differences in patients’ severity of illness. For a hospital-volume threshold of 400, the odds ratios for low-volume hospitals versus high-volume hospitals were 1.98 (95% CI, 1.17, 3.35) for in-hospital mortality, 2.07 (95% CI, 1.36, 3.15) for same-day CABG surgery, and 1.51 (95% CI, 1.03, 2.21) for same-stay CABG surgery. For an operator-volume threshold of 75, the odds ratios for low-volume versus high-volume operators were 1.65 (95% CI, 1.05, 2.60) for same-day CABG surgery and 1.55 (95% CI, 1.10, 2.18) for same-stay CABG surgery. Operator volume was not significantly associated with mortality. Also, for hospital volumes below 400 and operator volumes below 75, the respective odds of mortality, same-day CABG surgery, and same-stay CABG surgery were 5.92, 4.02, and 3.92 times the odds for hospital volumes of 400 or higher and operator volumes of 75 or higher.

Conclusions— Higher-volume operators and hospitals continue to experience lower risk-adjusted PCI outcome rates.

Importance of the postdischarge interval in assessing major adverse clinical event rates following percutaneous coronary intervention

In-hospital major adverse clinical event (MACE) rates after percutaneous coronary intervention serve as benchmarks of performance. However, accelerated clinical pathways, decreased lengths of stay, and potential delayed effects of percutaneous coronary intervention may result in an underestimation of this traditional measurement of outcome. Records from patients in the first 3 waves of the National Heart, Lung, and Blood Institute's Dynamic Registry (n = 6,676) were reviewed for rates of composite in-hospital MACEs (death, myocardial infarction, and any repeat target vessel revascularization) and postdischarge MACEs (death, myocardial infarction, repeat hospitalization, and repeat target vessel revascularization) through 30 days. Rates for each composite MACE were compared across waves to assess changes over time. Predictors of each MACE category were identified using multivariate analysis. In-hospital MACE decreased significantly (5.4% of wave 1, 4.9% of wave 2, 3.1% of wave 3, p <0.001), whereas stent implantation increased significantly (67.5% of wave 1, 79.1% of wave 2, 86.2% of wave 3, p <0.001). Postdischarge MACE through 30 days remained unchanged (5.1% of wave 1, 5.1% of wave 2, 4.8% of wave 3, p = 0.6). Mean length of stay decreased (2.7 days for wave 1, 2.2 days for wave 3, p <0.001). Disparate clinical, procedural, and angiographic factors were associated with each MACE. Postdischarge MACE rates through 30 days comprise a significant and unchanging fraction of overall procedurally related MACE rates despite improving in-hospital outcomes. Most postdischarge events derive from pathology related to the controlled vessel. A 30-day MACE rate may serve as a more comprehensive measurement of procedural outcome.

Real-world bare metal stenting: identification of patients at low or very low risk of 9-month coronary revascularization

The high cost of drug-eluting stents (DESs) has made identification of patients who are at low risk for subsequent revascularization after treatment with bare metal stents (BMSs) highly desirable. Previous reports from randomized trials suffer from biases induced by restricted entry criteria and protocol-mandated angiographic follow-up. Between 1994 and 2001, 5,239 consecutive BMS patients, excluding those with coil stents, technical failure, brachytherapy, staged procedure, or stent thrombosis within 30 days, were prospectively identified from a large single-center tertiary-referral-center prospective registry for long-term follow-up. We sought to identify characteristics of patients with very low (< or = 4%) or low (4-10%) likelihood of coronary revascularization 9 months after BMS. Nine-month clinical follow-up was obtained in 98.2% of patients. Coronary revascularization was required in 13.4% and did not differ significantly by stent type. On the basis of multivariate analysis identifying 11 independent correlates and previous reports, 20 potential low-risk patient and lesion groups (228 +/- 356 patients/groups) were identified (e.g, patients with all of the following: native vessel, de novo, reference diameter > or = 3.5 mm, lesion length < 5 mm, no diabetes, not ostial in location). Actual and model-based outcomes were analyzed. No group had both predicted and observed 9-month revascularization < or = 4% (very low risk). Conversely, 19 of 20 groups had a predicted and observed revascularization rate of 4-10% (low risk). In the real-world setting, the need for intermediate-term revascularization after BMS may be lower than expected, but it may be very difficult to identify patients at very low risk. Conversely, if the benefits of DESs are attenuated in routine practice, many groups of patients treated with BMSs may have nearly comparable results.

Hospital percutaneous coronary intervention volume and patient mortality, 1998 to 2000: does the evidence support current procedure volume minimums?

OBJECTIVES

The aim of this study was to evaluate current American College of Cardiology/American Heart Association (ACC/AHA) hospital percutaneous coronary intervention (PCI) volume minimum recommendations.

BACKGROUND

In order to reduce procedure-associated mortality, ACC/AHA guidelines recommend that hospitals offering PCIs perform at least 400 PCIs annually. It is unclear whether this volume standard applies to current practice.

METHODS

We conducted a retrospective analysis of the Agency for Healthcare Research and Quality's Nationwide In-patient Sample hospital discharge database to evaluate in-hospital mortality among patients (n = 362748) who underwent PCI between 1998 and 2000 at low (5 to 199 cases/year), medium (200 to 399 cases/year), high (400 to 999 cases/year), and very high (1000 cases or more/year) PCI volume hospitals.

RESULTS

Crude in-hospital mortality rates were 2.56% in low-volume hospitals, 1.83% in medium-volume hospitals, 1.64% in high-volume hospitals, and 1.36% in very high-volume hospitals (p < 0.001 for trend). Compared with patients treated in high-volume hospitals (odds ratio [OR] 1.00, referent), patients treated in low-volume hospitals remained at increased risk for mortality after adjustment for patient characteristics (OR 1.21, 95% confidence interval [CI] 1.06 to 1.28). However, patients treated in medium-volume hospitals (OR 1.02, 95% CI 0.92 to 1.14) and patients treated in very high-volume hospitals (OR 0.94, 95% CI 0.85 to 1.03) had a comparable risk of mortality. Findings were similar when high- and very high-volume hospitals were pooled together.

CONCLUSIONS

We found no evidence of higher in-hospital mortality in patients undergoing PCI at medium-volume hospitals compared with patients treated at hospitals with annual PCI volumes of 400 cases of more, suggesting current ACC/AHA PCI hospital volume minimums may merit reevaluation.

Clinical and economic outcomes of percutaneous coronary interventions in the elderly: an analysis of medicare claims data

BACKGROUND

Outcomes after percutaneous coronary intervention (PCI) have been documented extensively in clinical trials and single-center series, but few data exist on the clinical and economic outcomes after PCI in an unselected population.

METHODS AND RESULTS

We used the Medicare Standard Analytic File to identify all initial PCI procedures performed in 1998 among a random sample of 5% of all Medicare beneficiaries > or =65 years of age. These patients (n=9868) were followed up for 1 year after PCI to identify clinical outcomes, medical resource use, and costs. Between 1 month and 1 year after PCI, 16.9% of patients required > or =1 repeat revascularization procedures. Mean 1-year medical care costs increased 5-fold among patients with repeat revascularization compared with those without (26,186 dollars versus 5344 dollars; P<0.001). After adjustment for baseline differences, the independent cost of repeat revascularization was 19,074 dollars (95% CI, 18,440 to 19,707). Assuming from previous studies that 85% of repeat revascularization procedures over the first year of follow-up are attributable to restenosis, the estimated clinical restenosis rate was 14.4%, and the 1-year economic burden of restenosis to the healthcare system was 2747 dollars per initial PCI procedure.

CONCLUSIONS

Among unselected elderly patients undergoing PCI, repeat revascularization occurs in approximately 14% and increases 1-year healthcare costs by >19,000 dollars per occurrence. These findings have important implications for the cost-effectiveness of new treatments that substantially reduce restenosis.