Does low individual operator coronary interventional procedural volume correlate with worse institutional procedural outcome?

Consensus document on the radial approach in percutaneous cardiovascular interventions: position paper by the European Association of Percutaneous Cardiovascular Interventions and Working Groups on Acute Cardiac Care** and Thrombosis of the European Society of Cardiology

Radial access use has been growing steadily but, despite encouraging results, still varies greatly among operators, hospitals, countries and continents. Twenty years from its introduction, it was felt that the time had come to develop a common evidence-based view on the technical, clinical and organisational implications of using the radial approach for coronary angiography and interventions. The European Association of Percutaneous Cardiovascular Interventions (EAPCI) has, therefore, appointed a core group of European and non-European experts, including pioneers of radial angioplasty and operators with different practices in vascular access supported by experts nominated by the Working Groups on Acute Cardiac Care and Thrombosis of the European Society of Cardiology (ESC). Their goal was to define the role of the radial approach in modern interventional practice and give advice on technique, training needs, and optimal clinical indications.

Physician procedure volume and complications of cardioverter-defibrillator implantation

BACKGROUND

The outcomes of procedures are often better when they are performed by more experienced physicians. We assessed whether the rate of complications after implantable cardioverter-defibrillator (ICD) placement varied with the volume of procedures a physician performed.

METHODS AND RESULTS

We studied 356 515 initial ICD implantations in the National Cardiovascular Data Registry-ICD Registry, performed by 4011 physicians in 1463 hospitals. We examined the relationship between physician annual ICD implantation volume and in-hospital complications, using hierarchical logistic regression to adjust for patient characteristics, implanting physician certification, hospital characteristics, hospital annual procedure volume, and the clustering of patients within hospitals and by physician. We repeated this analysis for ICD subtypes: single chamber, dual chamber, and biventricular. There were 10 994 patients (3.1%) with a complication after ICD implantation, and 1375 died (0.39%). The complication rate decreased with increasing physician procedure volume from 4.6% in the lowest quartile to 2.9% in the highest quartile (P<0.0001), and the mortality rate decreased from 0.72% to 0.36% (P<0.0001). The inverse relationship between physician procedure volume and complications remained significant after adjusting for patient, physician, and hospital characteristics (OR 1.55 for complications in lowest-volume quartile compared with highest; 95% confidence interval, 1.34-1.79; P<0.0001). This inverse relationship was independent of physician specialty and of hospital volume, was consistent across ICD subtypes, and was also evident for in-hospital mortality.

CONCLUSION

Physicians who implant more ICDs have lower rates of procedural complications and in-hospital mortality, independent of hospital procedure volume, physician specialty, and ICD type.

From staff-mix to skill-mix and beyond: towards a systemic approach to health workforce management

Throughout the world, countries are experiencing shortages of health care workers. Policy-makers and system managers have developed a range of methods and initiatives to optimise the available workforce and achieve the right number and mix of personnel needed to provide high-quality care. Our literature review found that such initiatives often focus more on staff types than on staff members' skills and the effective use of those skills. Our review describes evidence about the benefits and pitfalls of current approaches to human resources optimisation in health care. We conclude that in order to use human resources most effectively, health care organisations must consider a more systemic approach--one that accounts for factors beyond narrowly defined human resources management practices and includes organisational and institutional conditions.

[Results of percutaneous coronary intervention in a hospital with a low case load]

Since efficacy of small volume centers performing coronary and angioplasty is questioned, we present our data for 2003. In 2003, 669 coronary examinations were performed in our unit (average age 68 years, 67% men) with 215 angioplasties. We take charge essentially Acute Coronary Syndrome (99%), with 37% ACS ST +. The radical approach was taken in 15% of cases. We used anti GP IIb/IIIa in 67% of cases (only abciximab), the rate of stenting was 84% with 43.6% of Direct Stenting. The primary angiographic results were good in 98% of cases. The rate of Restenosis was 6%. The hospital mortality was 2.8%. So we think that coronary and angioplasty in a small volume center can be performed with safety and a level of success in accordance with the data of the literature.

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.

Reperfusion treatment of ST-elevation acute myocardial infarction

Reperfusion treatment of ST-segment elevation myocardial infarction (STEMI) is one of the medical interventions with the largest potential for saving human lives, independently of age and gender. An attempt to reopen an acutely occluded coronary artery can be done within a wide array of possibilities, from the simple administration of aspirin to the combination of drugs and complex coronary artery interventions. Fibrinolytic drugs and aspirin represent the easiest way to attempt reperfusion and together offer an acceptable compromise between opportunity for treatment and efficacy. Other drugs and the use of invasive revascularization alternatives yield further advantages, and in some high-risk subgroups may be the most rational treatment approach. Beyond investigator's bias and dedication to either form of reperfusion treatment, interventions and/or drugs should be used as needed (and as possible) to increase the overall impact of reperfusion treatment in the community, taking advantage of the best potential of each approach. Most resources have been directed toward the improvement of reperfusion rates with the combination of fibrinolytic and antiplatelet drugs or with angioplasty. These efforts have certainly raised costs, but have not decisively improved clinical outcome nor have they broadened the impact of reperfusion treatment in the community. Indeed, the main shortcoming of reperfusion therapy is that the cohort of untreated patients is still larger than the cohort of treated patients. At a time when mortality of patients with STEMI reaching the hospital and receiving treatment has decreased significantly, the prehospital diagnosis and treatment of STEMI with the objective of enlarging the treated population and shortening the pretreatment delays is likely the best strategy to further reduce mortality. The need for a population approach to treatment of STEMI is even more obvious when considering the expanding patient load that continuously worsens its clinical risk profile, together with the increasing incidence of diabetes, obesity, hypertension, and smoking habits. The target for improving reperfusion treatment of STEMI in the future, and thereby saving more lives, seems now to involve a cultural change and fulfillment of an organizational mission more than an incremental improvement in the current pharmacologic or interventional approach. These epidemiologic and social aspects of contemporary medicine deserve full attention at a time when researchers, clinicians, and health care providers tend to focus primarily on technological advances.

The volume-outcome relationship: from Luft to Leapfrog

Numerous reports have documented a volume-outcome relationship for complex medical and surgical care, although many such studies are compromised by the use of discharge abstract data, inadequate risk adjustment, and problematic statistical methodology. Because of the volume-outcome association, and because valid outcome measurements are unavailable for many procedures, volume-based referral strategies have been advocated as an alternative approach to health-care quality improvement. This is most appropriate for procedures with the greatest outcome variability between low-volume and high-volume providers, such as esophagectomy and pancreatectomy, and for particularly high-risk subgroups of patients. Whenever possible, risk-adjusted outcome data should supplement or supplant volume standards, and continuous quality improvement programs should seek to emulate the processes of high-volume, high-quality providers. The Leapfrog Group has established a minimum volume requirement of 500 procedures for coronary artery bypass grafting. In view of the questionable basis for this recommendation, we suggest that it be reevaluated.

Learning curves in health care

This article explores the uses of learning curve theory in medicine. Though effective application of learning curve theory in health care can result in higher quality and lower cost, it is seldom methodically applied in clinical practice. Fundamental changes are necessary in the corporate culture of medicine in order to capitalize maximally on the benefits of learning.

Effects of hospital volume on long-term outcomes after percutaneous transluminal coronary angioplasty after acute myocardial infarction

BACKGROUND

Volume of procedures has been associated with short-term outcome after percutaneous transluminal coronary angioplasty. However, the effect of hospital procedural volume on long-term outcome after PTCA is unknown.

METHODS AND RESULTS

We analyzed the physician claims and discharge data of 6635 patients who underwent PTCA after acute myocardial infarction (AMI) between 1991 and 1995 in the province of Quebec, Canada. For each administrative year, hospitals in which PTCA was performed were classified into 3 groups: low-volume, <200 procedures per year; medium-volume, 200 to 399 procedures per year; and high-volume, > or =400 procedures per year. Compared with patients in medium-volume and high-volume hospitals, patients in low-volume hospitals were older, had more recent AMI, and were less likely to have been transferred for PTCA. After adjustment for baseline differences, patients in the low-volume and medium-volume groups were more likely to undergo CABG within 6 months compared with patients in the high-volume group (odds ratio [OR] 2.1, 95% CI 1.3-3.3, and OR 1.5, 95% CI 1.2-1.9, respectively). In contrast, patients in the low-volume and medium-volume groups were less likely than patients in the high-volume group to undergo repeat PTCA within 6 months (OR 0.37, 95% CI 0.24-0.58, and OR 0.8, 95% CI 0.70-0.92, respectively). At 6 months, adjusted rates of repeat revascularization, recurrent AMI, or death did not differ between the 3 groups.

CONCLUSION

Overall adverse event rates at 6 months after PTCA do not differ between hospital volume groups. The higher rate of CABG in low-volume hospitals and the higher rate of repeat PTCA in high-volume hospitals may represent different physician preferences for the treatment of failed PTCA rather than higher complication rates.

[Continuous practice and advanced training in interventional cardiology. Recommendations for the assessment and maintenance of proficiency in interventional cardiology. A statement for physicians and advanced training units from the Section of Hemodynamics and Interventional Cardiology of the Spanish Society of Cardiology]

This report reflects the interest of the Section of Hemodynamics and Interventional Cardiology of the Spanish Society of Cardiology in increasing quality, safety and applicability of percutaneous procedures, by giving scientific keys aimed at improving related functions of teaching or planning in this field and enhancing competence and prestige of Spanish interventional cardiologists. The purpose of the document is to describe the importance of current interventional cardiology, to identify quality references and to establish minimum acceptable requirements for assessing and maintaining the competence of practicing or providing advanced training in this discipline. To achieve this goal, a search for a gold standard of the different techniques of general interventional practice was carried out, and predictors of postprocedural outcome were analyzed, as well as their relation with different kinds of circumstances. This analysis identified coronary angioplasty as the standard on which recommendations regarding competence in overall interventional cardiology standards of quality and assessment and maintenance of proficiency must be based. On the other hand, the strong influence of experience and knowledge of results has been documented, especially in high-risk or high-complexity settings. On this basis, the report establishes specific recommendations about proficiency for practice and advanced training. It also suggests that interventional cardiology should be considered as a subspecialty, of cardiology requiring specific credentials.

Application of the New York State PTCA mortality model in patients undergoing stent implantation

BACKGROUND

This study applied the New York State conventional coronary angioplasty (PTCA) model of clinical outcomes to evaluate whether it has relevance in the current era of stent implantation. The model was developed in 62 670 patients treated with conventional PTCA from 1991 to 1994 to risk adjust mortality and bypass surgery after PTCA. Since then, stents have become the dominant form of intervention. Whether that model remains relevant is uncertain.

METHODS AND RESULTS

All patients undergoing stenting at the Mayo Clinic from 1995 to 1998 were analyzed for in-hospital mortality, bypass surgery performed after attempted stenting, and longer-term mortality. No patients were excluded. The New York model was used to risk adjust and predict in-hospital and follow-up mortality. There were 3761 patients with 4063 procedural admissions for stenting; 6,472 target vessel segments were attempted, and 96.1% of procedures were successful. With the New York multivariable risk factor equation, 79 in-hospital deaths were expected (1.95%); 66 deaths (1.62%) were observed. The New York model risk score in a logistic regression model was the most significant factor associated with in-hospital mortality (OR, 1.86; P<0.001). During a mean follow-up of 1.2+/-1.0 years, there were 154 deaths. Multivariable analysis documented 6 factors associated with subsequent mortality; New York risk score was the most significant (chi(2)=16.64, P=0.0001).

CONCLUSIONS

Although the New York mortality model was developed in an era of conventional angioplasty, it remains relevant in patients undergoing stenting. The risk score derived from that model is the variable most significantly associated with not only in-hospital but also longer-term outcome.

Prediction of death after percutaneous coronary interventional procedures

BACKGROUND

The prediction and comparison of procedural death after percutaneous coronary interventional procedures is inherently difficult because of variations in case mix and practice patterns. The impact of modern, expanded patient selection criteria, and newer technologic approaches is unknown. Our objective was to determine whether a risk equation based on patient-related variables and derived from an independent data set can accurately predict procedural death after percutaneous coronary intervention in the current era.

METHODS AND RESULTS

An analysis was made of the Mayo Clinic Coronary Interventional Database January 1, 1995, to October 31, 1997. Expected mortality rate was calculated with the use of the New York State multivariate risk score. In 3387 patients, 3830 procedures (55.1% stents) were performed, with an expected mortality rate of 2.32% and observed mortality rate of 2.38% (P = not significant). The risk score derived from the New York multivariate model was highly predictive of death (chi-square = 213.8; P <.0001). The presence of a high-risk lesion characteristic such as calcium, thrombus, or type C lesion was modestly associated with death.

CONCLUSIONS

The New York State multivariate model accurately predicted procedural death in our database.

Frequency of major adverse cardiac events within one month of coronary angioplasty: a useful measure of operator performance

OBJECTIVES

To test one-month outcomes in a single center for their statistical power to corroborate conclusions derived from large multicenter databases.

BACKGROUND

Only with large, multicenter databases has it been possible to demonstrate more frequent occurrences of complications in patients treated by "low-volume operators." Critics feel that such analyses mask excellent performance by many "low-volume operators."

METHODS

In a high-volume cardiac catheterization laboratory in a large, nonuniversity teaching hospital, baseline clinical and angiographic characteristics were collected for a consecutive series of 1,029 patients treated by 37 percutaneous transluminal coronary intervention (PTCI) operators over a four-month period. One-month follow-up was obtained in 967 (94%) patients who form the basis for this analysis.

RESULTS

Only the group of operators performing <50 cases annually had a major adverse cardiac event (MACE) (death, myocardial infarction or symptom-driven revascularization) rate at one month significantly greater than predicted from baseline characteristics. (Observed rate: 15.1%, expected: 9.7%, 95% confidence interval [CI]: 4.7%, 14.6%.) The difference was driven by the significantly more frequent rate at which repeat revascularization was performed in patients treated by that group of operators (observed: 13.8%, expected: 7.1%, 95% CI: 2.8%, 11.4%).

CONCLUSIONS

As is true of analyses of large multicenter databases, lower volume operators as a group have less good outcomes than those performing more. The greater statistical power provided by one-month MACE rate offers advantages over the use of in-hospital complications for the analysis of operator performance.

The relationship between operator volume and outcomes after percutaneous coronary interventions in high volume hospitals in 1994-1996: the northern New England experience. Northern New England Cardiovascular Disease Study Group

OBJECTIVES

The purpose of this study was to examine the relationship between annual operator volume and outcomes of percutaneous coronary interventions (PCIs) using contemporaneous data.

BACKGROUND

The 1997 American College of Cardiology (ACC)/American Heart Association task force based their recommendation that interventionists perform > or = 75 procedures per year to maintain competency in PCI on data collected largely in the early 1990s. The practice of interventional cardiology has since changed with the availability of new devices and drugs.

METHODS

Data were collected from 1994 through 1996 on 15,080 PCIs performed during 14,498 hospitalizations by 47 interventional cardiologists practicing at the five high volume (>600 procedures per hospital per year) hospitals in northern New England and one Massachusetts-based institution that support these procedures. Operators were categorized into terciles based on their annualized volume of procedures. Multivariate regression analysis was used to control for case-mix. In-hospital outcomes included death, emergency coronary artery bypass graft surgery (eCABG), non-emergency CABG (non-eCABG), myocardial infarction (MI), death and clinical success (> or = 1 attempted lesion dilated to < 50% residual stenosis and no death, CABG or MI).

RESULTS

Average annual procedure rates varied across terciles from low = 68, middle = 115 and high = 209. After adjusting for case-mix, clinical success rates were comparable across terciles (low, middle and high terciles: 90.9%, 88.8% and 90.7%, Ptrend = 0.237), as were all the adverse outcomes including death (low-risk patients = 0.45%, 0.41%, 0.71%, Ptrend = 0.086; high-risk patients = 5.68%, 5.99%, 7.23%, Ptrend = 0.324), eCABG (1.74%, 2.05%, 1.75%, Ptrend = 0.733) and MI (2.57%, 1.90%, 1.86%, Ptrend = 0.065).

CONCLUSIONS

Using current data, there is no significant relationship between operator volumes averaging > or = 68 per year and outcomes at high volume hospitals. Future efforts should be directed at determining the generalizability of these results.

Operator volume and outcome of patients undergoing coronary stent placement

OBJECTIVES

The aim of this study was to assess the relation between operator experience in coronary stent placement procedures and the clinical outcome of patients.

BACKGROUND

The results of coronary balloon angioplasty are closely related to the experience of the operator performing the procedure. Data on the effect of operator experience on the results after coronary stent placement are missing.

METHODS

The study included 3,409 consecutive patients undergoing coronary stent placement for the management of coronary artery disease. A composite end point of cardiac death, myocardial infarction and aortocoronary bypass surgery during the first 30 days after the intervention, was the primary end point and the procedural failure was the secondary end point of the study.

RESULTS

Adverse clinical outcome occurred in 2.99% of the 3,409 patients undergoing coronary stent placement. Procedural failure was recorded in 2.08% of the patients. Operator volumes above 483 procedures were associated with a risk-adjusted adverse outcome rate of 1.70%+/-1.28%, which is significantly lower than the overall rate of 2.99%. Operator yearly volumes of under 90 procedures were associated with a risk-adjusted adverse outcome rate of 4.59%+/-1.17%, which is significantly higher than the overall rate of 2.99%. The operator experience was an independent predictor even after adjusting for the effect of other risk factors. The analysis demonstrated that an experience of at least 100 procedures is required to obtain better outcome even in patients with simple coronary lesions and that operators should perform at least 70 procedures annually to expect a better outcome in patients with both simple and complex coronary lesions.

CONCLUSIONS

Operator experience is a significant and independent predictor of the outcome of patients undergoing coronary stent placement. An experience of at least 100 procedures and an annual volume of at least 70 procedures are required to ensure a significantly better outcome after coronary stent implantation.

Operator volume and outcomes in 12,998 percutaneous coronary interventions. Northern New England Cardiovascular Disease Study Group

OBJECTIVES

We sought to determine whether there is a relation between operator volume and outcomes for percutaneous coronary interventions (PCIs).

BACKGROUND

A 1993 American College of Cardiology/American Heart Association task force stated that cardiologists should perform > or = 75 procedures/year to maintain competency in PCIs; however, there were limited data available to support this statement.

METHODS

Data were collected from 1990 through 1993 on 12,988 PCIs (12,118 consecutive hospital admissions) performed by 31 cardiologists at two hospitals in New Hampshire and two in Maine and one hospital in Massachusetts supporting these procedures. Operators were categorized into terciles based on annualized volume of procedures. Univariate and multivariate regression analyses were used to control for case-mix. Successful outcomes included angiographic success (all lesions attempted dilated to < 50% residual stenosis) and clinical success (at least one lesion dilated to < 50% residual stenosis and no adverse outcomes). In-hospital adverse outcomes included coronary artery bypass graft surgery (CABG), myocardial infarction (MI) and death.

RESULTS

After adjustment for case-mix, higher angiographic (low, middle and high terciles: 84.7%, 86.1% and 90.3%, p-trend 0.006) and clinical success rates (85.8%, 88.0% and 90.7%, p-trend 0.025), with fewer referrals to CABG (4.54%, 3.75% and 2.49%, p-trend <0.001), were seen as operator volume increased. There was a trend toward higher MI rates for high volume operators (2.00%, 1.98% and 2.57%, p-trend 0.06); all terciles had similar in-hospital mortality rates (1.09%, 0.96% and 1.05%, p-trend 0.8).

CONCLUSIONS

There is a significant relation between operator volume and outcomes in PCIs. Efforts should be directed toward understanding why high volume operators are more successful and encounter fewer adverse outcomes.