Hospital volume of throughput and periprocedural and medium-term adverse events after percutaneous coronary intervention: retrospective cohort study of all 17 417 procedures undertaken in Scotland, 1997-2003

Abstract

Objective: To determine whether percutaneous coronary intervention (PCI) hospital volume of throughput is associated with periprocedural and medium-term events, and whether any associations are independent of differences in case mix. Design: Retrospective cohort study of all PCIs undertaken in Scottish National Health Service hospitals over a six-year period. Methods: All PCIs in Scotland during 1997-2003 were examined. Linkage to administrative databases identified events over two years' follow up. The risk of events by hospital volume at 30 days and two years was compared by using logistic regression and Cox proportional hazards models. Results: Of the 17 417 PCIs, 4900 (28%) were in low-volume hospitals and 3242 (19%) in high-volume hospitals. After adjustment for case mix, there were no significant differences in risk of death or myocardial infarction. Patients treated in high-volume hospitals were less likely to require emergency surgery (adjusted odds ratio 0.18, 95% confidence interval (CI) 0.07 to 0.54, p = 0.002). Over two years, patients in high-volume hospitals were less likely to undergo surgery (adjusted hazard ratio 0.52, 95% CI 0.35 to 0.75, p = 0.001), but this was offset by an increased likelihood of further PCI. There was no net difference in coronary revascularisation or in overall events. Conclusion: Death and myocardial infarction were infrequent complications of PCI and did not differ significantly by volume. Emergency surgery was less common in high-volume hospitals. Over two years, patients treated in high-volume centres were as likely to undergo some form of revascularisation but less likely to undergo surgery. W hen first introduced more than 20 years ago, percutaneous coronary intervention (PCI) was undertaken in only a few hospitals, with on-site cardiac surgical cover in case patients had coronary occlusion or dissection as a complication of PCI. With the development of coronary stents, the need for emergency referral for surgery fell dramatically, and PCI is now undertaken in an increasing number of sites.As with all interventions there is a balance to be struck. In low-volume centres, operators may find it more difficult to maintain their level of expertise and keep abreast of new advances. However, the likelihood has been well established that patients undergoing any procedure, including revascularisation, in part depends on their geographical distance from the intervention centre.1 Restricting interventions to fewer high-volume centres therefore inevitably leads to geographical inequalities in access to health care.It has been suggested that PCIs should be undertaken only in hospitals performing a minimum of 400 PCIs per annum. 2PCI volume of throughput has even been proposed as a generic marker of quality of care within hospitals.3 However, published studies have produced conflicting results on whether periprocedural complications are less likely to occur in higher-volume institutions.4-11 Furthermore, we are unaware of any studies published to date examining whether hospital vo...

Impact of Annual Operator and Institutional Volume on Percutaneous Coronary Intervention Outcomes

“…The relationship of these outcomes and operator or institutional volume has not been shown earlier. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]35 Our study demonstrates a statistically significant inverse association between operator volume and outcome (in-hospital mortality and peri-procedural complications) in the current practice. Our results are in agreement with results from previous studies done both in the percutaneous transluminal coronary angioplasty and the stent era.…”

“…Our results are in agreement with results from previous studies done both in the percutaneous transluminal coronary angioplasty and the stent era. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]35,36 Previous studies have been limited by the number of centers, 12,20 state-based registry data, 8,14,15,18 inclusion of only limited cohorts, 16 lower sample size, 8,9,[11][12][13][14][15][16][17][18]20 foreign studies, 11,19,21 and most importantly they lack data from recent era. 6,7,9,16 Previous studies, which have shown a decrease in mortality with increasing operator volume, have failed to reach statistical significance because of low sample size, large confidence interval, or low procedure related mortality.…”

“…Some of these data were derived from state registries and are dated. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] The purpose of this study was to determine the association of annual PCI operator and institutional volume with in-hospital mortality, peri-procedural complications, length of hospital stay, and cost of hospitalization using the nation's largest available all-payer insurance inpatient database in a recent era (2005)(2006)(2007)(2008)(2009)) during which procedural techniques and practices have remained relatively stable.…”

Relationship between hospital volume and risk-adjusted mortality rate following percutaneous coronary intervention in Korea, 2003 to 2004

“…That is patients treated at high-volume hospitals encounter a lower risk of mortality when compared with patients treated at low-volume hospitals. But Burton et al (20) AMI -acute myocardial infarction, CHF -congestive heart failure, CI -confidence interval, COPD -chronic obstructive pulmonary disease, OR -odds ratio, , PCI -percutaneous coronary intervention (4) suggested that there is narrowing difference in mortality rates between high-and medium-volume hospitals due to accumulating experience with PCI procedures among surgeons, especially those serving in medium-PCI volume hospitals. In our study, crude 30-day mortality rate was 1.1% (Table 2).…”

The management of patients with stable coronary syndromes

“…The published results from large real-world registries of usual practice indicate that the short-term risks are not negligible. (25,26) Patients and practitioners sometimes view PCI as a "holding" procedure, which delays CABG and there is a defi nite increase in the need for repeat revascularization, often by CABG, in patients initially treated by PCI. There is at least one observational study suggesting disturbingly that prior PCI may increase (double) in-hospital mortality after CABG.…”