Operator volume and outcome of patients undergoing coronary stent placement

Impaired Kidney Function and 10-Year Outcome After Percutaneous Coronary Intervention-Interaction with Age, Sex, Diabetic Status and Clinical Presentation

Background: Limited evidence exists regarding the association of chronic kidney disease (CKD) with long-term outcomes following percutaneous coronary intervention (PCI). We aimed to assess the association of CKD with 10-year outcome after PCI. Methods: This study included 5571 patients with coronary artery disease (CAD) undergoing PCI. Patients were categorized in groups according to the estimated glomerular filtration rate (eGFR) values: eGFR ≥ 90 mL/min/1.73 m2, (normal kidney function), 60 to <90 mL/min/1.73 m2 (mild kidney impairment), 30 to <60 mL/min/1.73 m2 (mild-to-moderate and moderate-to-severe kidney impairment) and <30 mL/min/1.73 m2 (severe kidney impairment). The primary endpoint was all-cause mortality at 10 years. Results: All-cause deaths occurred in 155 patients (86.3%) with eGFR < 30 mL/min/1.73 m2, 602 patients (59.1%) with eGFR 30 to <60 mL/min/1.73 m2, 775 patients (31.3%) with eGFR 60 to <90 mL/min/1.73 m2 and 220 patients (15.8%) with eGFR ≥ 90 mL/min/1.73 m2 (adjusted hazard ratio = 2.16, 95% confidence interval 1.84 to 2.54, p < 0.001, for 30 mL/min/1.73 m2 decrement in the eGFR). There were CKD-by-age (Pint < 0.001) and CKD-by-clinical presentation (Pint = 0.017) interactions showing a stronger association of CKD with mortality in younger patients and those presenting with acute coronary syndromes. The C statistic of the multivariable model for mortality increased from 0.748 [0.737-0.759] to 0.766 [0.755-0.777] (p < 0.001) after the inclusion of eGFR in the model. Conclusions: In patients with CAD undergoing PCI, CKD was associated with higher mortality at 10 years compared with patients with preserved renal function. The association between CKD and mortality was stronger in patients of younger age and those presenting with acute coronary syndromes.

Assessment of Impact of Patient Recruitment Volume on Risk Profile, Outcomes, and Treatment Effect in a Randomized Trial of Ticagrelor Versus Prasugrel in Acute Coronary Syndromes

BACKGROUND

Whether there are differences in the risk profile and treatment effect in patients recruited in a low recruitment center (LRC) versus patients recruited in a high recruitment center (HRC) in a randomized multicenter trial remains unknown.

METHODS AND RESULTS

This study included 4018 patients with acute coronary syndrome recruited in the ISAR‐REACT 5 (Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 5) trial. The primary end point was a composite of all‐cause death, myocardial infarction, or stroke. Overall, 3011 patients (75%) were recruited in the HRCs (7 centers recruiting 258 to 628 patients; median, 413 patients) and 1007 patients (25%) were recruited in the LRCs (16 centers recruiting 5 to 201 patients; median, 52 patients). Patients recruited in the LRCs had more favorable cardiovascular risk profiles than patients recruited in the HRCs. The primary end point occurred in 72 patients in the LRCs and 249 patients in the HRCs (cumulative incidence, 7.3% and 8.4%; P=0.267). All‐cause mortality was lower among patients recruited in the LRCs (n=29) than among patients recruited in the HRCs (n=134; cumulative incidence 2.9% versus 4.5%; P=0.031). There was no significant interaction between the treatment effect of ticagrelor versus prasugrel and patient recruitment category (LRC versus HRC) regarding the primary efficacy end point (LRC: hazard ratio [HR], 1.42 [95% CI, 0.89–2.28]; HRC: HR, 1.33 [95% CI, 1.04−1.72]; P for interaction=0.800).

CONCLUSIONS

Patients with acute coronary syndrome recruited in a LRC appear to have more favorable cardiovascular risk profiles and lower 1‐year mortality rates compared with patients recruited in a HRC. The recruitment volume did not interact with the treatment effect of ticagrelor versus prasugrel.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01944800.

Outcomes of PCI in Relation to Procedural Characteristics and Operator Volumes in the United States

BACKGROUND

Professional guidelines have reduced the recommended minimum number to an average of 50 percutaneous coronary intervention (PCI) procedures performed annually by each operator. Operator volume patterns and associated outcomes since this change are unknown.

OBJECTIVES

The authors describe herein PCI operator procedure volumes; characteristics of low-, intermediate-, and high-volume operators; and the relationship between operator volume and clinical outcomes in a large, contemporary, nationwide sample.

METHODS

Using data from the National Cardiovascular Data Registry collected between July 1, 2009, and March 31, 2015, we examined operator annual PCI volume. We divided operators into low- (<50 PCIs per year), intermediate- (50 to 100 PCIs per year), and high- (>100 PCIs per year) volume groups, and determined the adjusted association between annual PCI volume and in-hospital outcomes, including mortality.

RESULTS

The median annual number of procedures performed per operator was 59; 44% of operators performed <50 PCI procedures per year. Low-volume operators more frequently performed emergency and primary PCI procedures and practiced at hospitals with lower annual PCI volumes. Unadjusted in-hospital mortality was 1.86% for low-volume operators, 1.73% for intermediate-volume operators, and 1.48% for high-volume operators. The adjusted risk of in-hospital mortality was higher for PCI procedures performed by low- and intermediate-volume operators compared with those performed by high-volume operators (adjusted odds ratio: 1.16 for low versus high; adjusted odds ratio: 1.05 for intermediate vs. high volume) as was the risk for new dialysis post PCI. No volume relationship was observed for post-PCI bleeding.

CONCLUSIONS

Many PCI operators in the United States are performing fewer than the recommended number of PCI procedures annually. Although absolute risk differences are small and may be partially explained by unmeasured differences in case mix between operators, there remains an inverse relationship between PCI operator volume and in-hospital mortality that persisted in risk-adjusted analyses.

MOrtality and infectious complications of therapeutic EndoVAscular interventional radiology: a systematic and meta-analysis protocol

BACKGROUND

Endovascular interventional radiology (EIR) is an increasingly popular, mini invasive treatment option for patient with symptomatic vascular disease. The EIR practiced by qualified hands is an effective, well-tolerated procedure that offers relief of patient's symptoms with a low risk of complications. During acute post procedural period, immediate complications may relate to vascular access, restenosis, thromboembolic events, uterine ischemia, infection, necrosis, sepsis, ICU stay, surgical recovery, pain management, treatment failure, and death. Moreover, additional non-life-threatening complications exist, but they are not well described and represent disparate information.

METHODS/DESIGN

A range of databases will be screened consulted to identify the relevant studies: PubMed, EMBASE, The Cochrane Library, NosoBase, and Google Scholar (to identify articles not yet indexed). Scientist librarian used Medical Subject Headings (MeSH) and free terms to construct the search strategy in PubMed. This search strategy will be adapted in other databases. Two coauthors will independently select the relevant studies, extract the relevant data, and assess the risk of bias in the included studies. Any disagreements between the two authors will be solved by a third author.

DISCUSSION

This systematic review will provide a synthesis of EIR complications. The spotlighted results will be analyzed in order to provide a state-of-knowledge synopsis of the current evidence base in relation to the epidemiology of the infectious complications after EIR. In the event of conclusive results, our findings will serve as a reference background to assess guidelines on reality of the problem of the infections linked to endovascular interventional radiology and to formulate of assumptions and propose preventive measures, based on the results of our investigations. These propositions will aim to reduce the risk and/or the severity of these complications in the concerned population in favor a positive medical economics report. It will also aim to decrease the antibio-resistance and in fine will improve health status and security of patients.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015025594.

Procedural safety and predictors of acute outcome of intracoronary administration of progenitor cells in 775 consecutive procedures performed for acute myocardial infarction or chronic heart failure

BACKGROUND

Cell-based therapies are a promising option in patients with acute myocardial infarction or chronic heart failure (CHF). However, administration of cells requires intracoronary or intracardiac instrumentation, which is potentially associated with periprocedural risks. Therefore, we analyzed periprocedural complications and 30-day outcome in 775 consecutive procedures of intracoronary administration of progenitor cells using the stop-flow technique.

METHODS AND RESULTS

Indications for cell administration were acute myocardial infarction (n=126) and CHF of ischemic (n=562) or nonischemic (n=87) etiology. Vessel injury was observed in a total of 9 procedures (1.2%) and could be promptly managed by additional progenitor cell injection (PCI) in all but 1 case. No procedural deaths were observed. A periprocedural increase in troponin T was observed in 3.2% of the CHF procedures, in which no concomitant PCI was performed and troponin levels were not elevated before the procedure. Independent significant predictors of troponin T increase were higher New York Heart Association (NYHA) class (NYHA I versus NYHA IV; P=0.01; NYHA I versus III; P=0.19; NYHA I versus II; P=0.55), concomitant revascularization (P<0.01), presence of elevated troponin T before the procedure (P<0.01), and peripheral occlusive disease (P=0.04). At 30 days, there were 4 deaths (0.5%), 1 stroke (0.13%), 8 acute myocardial infarctions (1%), and 5 hospitalizations for exacerbation of heart failure (0.64%).

CONCLUSIONS

Intracoronary infusion of progenitor cells can be performed with adequate safety in patients with acute myocardial infarction or CHF, because the safety profile was similar to what is usually expected from a coronary angiogram in the present cohort.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00962364, NCT00284713, and NCT00289822.

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.

Quality of reporting internal and external validity data from randomized controlled trials evaluating stents for percutaneous coronary intervention

BACKGROUND

Stents are commonly used to treat patients with coronary artery disease. However, the quality of reporting internal and external validity data in published reports of randomised controlled trials (RCTs) of stents has never been assessed.The objective of our study was to evaluate the quality of reporting internal and external validity data in published reports of RCTs assessing the stents for percutaneous coronary interventions.

METHODS

A systematic literature review was conducted. Reports of RCTs assessing stents for percutaneous coronary interventions indexed in MEDLINE and the Cochrane Central Register of Controlled Trials and published between January 2003 and September 2008 were selected. A standardized abstraction form was used to extract data. All analyses were adjusted for the effect of clustering articles by journal.

RESULTS

132 articles were analyzed. The generation of the allocation sequence was adequate in 58.3% of the reports; treatment allocation was concealed in 34.8%. Adequate blinding was reported in one-fifth of the reports. An intention-to-treat analysis was described in 79.5%. The main outcome was a surrogate angiographic endpoint in 47.0%. The volume of interventions per center was described in two reports. Operator expertise was described in five (3.8%) reports. The quality of reporting was better in journals with high impact factors and in journals endorsing the CONSORT statement.

CONCLUSION

The current reporting of results of RCTs testing stents needs to be improved to allow readers to appraise the risk of bias and the applicability of the results.

A systematic review of the impact of volume of surgery and specialization on patient outcome

BACKGROUND AND METHODS

Volume of surgery and specialization may affect patient outcome. Articles examining the effects of one or more of three variables (hospital volume of surgery, surgeon volume and specialization) on outcome (measured by length of hospital stay, mortality and complication rate) were analysed. Reviews, opinion articles and observational studies were excluded. The methodological quality of each study was assessed, a correlation between the variables analysed and the outcome accepted if it was significant.

RESULTS

The search identified 55,391 articles published between 1957 and 2002; 1075 were relevant to the study, of which 163 (9,904,850 patients) fulfilled the entry criteria. These 163 examined 42 different surgical procedures, spanning 13 surgical specialities. None were randomized and 40 investigated more than one variable. Hospital volume was reported in 127 studies; high-volume hospitals had significantly better outcomes in 74.2 per cent of studies, but this effect was limited in prospective studies (40 per cent). Surgeon volume was reported in 58 studies; high-volume surgeons had significantly better outcomes in 74 per cent of studies. Specialization was reported in 22 studies; specialist surgeons had significantly better outcomes than general surgeons in 91 per cent of studies. The benefit of high surgeon volume and specialization varied in magnitude between specialities.

CONCLUSION

High surgeon volume and specialization are associated with improved patient outcome, while high hospital volume is of limited benefit.

Outcome of percutaneous coronary intervention in hospitals with and without on-site cardiac surgery standby

OBJECTIVE

To compare characteristics and outcome of patients undergoing percutaneous coronary intervention (PCI) in clinics with (WSB) or without (NOSB) on-site cardiac surgery backup.

DESIGN

Analysis according to hospital, type of prospectively collected data of all patients who underwent PCI during 2000-3.

SETTING

The Swedish Coronary Angiography and Angioplasty Registry covers all PCI procedures performed in Sweden.

PATIENTS

34,363 patients underwent PCI between January 2000 and December 2003. 8838 procedures were performed in NOSB (mean age of patients was 64.5 years) hospitals and 25,525 in WSB (mean age of patients was 64.1 years) hospitals (p = 0.002).

RESULTS

More patients in NOSB hospitals had diabetes (17.8% vs 16.8%; p = 0.03). Other clinical characteristics (previous infarct, previous coronary artery bypass graft (CABG)) also showed a tendency towards worse patients being treated in NOSB hospitals. However, there was a higher percentage of patients with ST-segment elevation myocardial infarction (18% vs 9.7%; p<0.01) in WSB hospitals. After adjusting for differences in baseline risk no significant differences regarding outcome (30-day mortality, 1-year mortality, stroke and emergency CABG) were observable between WSB and NOSB hospitals. This applied to elective and non-elective procedures.

CONCLUSIONS

On the basis of these data it does not seem warranted to recommend against percutaneous transluminal coronary angioplasty in NOSB hospitals.

Quality Management and Volume-Related Outcomes in the Cardiac Catheterization Laboratory

The assessment of quality in the cardiac catheterization laboratory is a complex, ongoing process that requires a comprehensive analysis of the multiple elements of quality. Although clinical outcomes are a reflection of the quality process, they derive from a complex interaction of clinical, technical, and process-of-care components. Procedural volume is associated but not equated with clinical outcomes, although the magnitude of this association depends on numerous covariates, most notably the diminishing rate of adverse outcomes over time.

Do operator volumes relate to clinical outcomes after percutaneous coronary intervention in the Canadian health care system?

BACKGROUND

Many US studies have documented an association between operator volume and outcomes after percutaneous coronary intervention (PCI). No study has assessed whether this relationship exists in Canada, where PCI is performed only at a limited number of regional centers and operator volumes are higher.

METHODS

All PCI procedures performed in the province of Ontario from 1995 to 2001 were analyzed using administrative databases. The outcomes of interest were coronary artery bypass graft during the same hospitalization, mortality at 30 days, or the combined end point.

RESULTS

A total of 38,561 PCI procedures were performed by 65 physicians at 8 centers. Over the study period, risk-adjusted coronary artery bypass graft rates fell from 2.0% in 1995 to 0.7% in 2000 (P < .0001) with no change in mortality. The median annual PCI volume was 132 (25th, 75th percentile: 81, 182) cases. After stratifying operators by average annual PCI volume into low (< 155 cases), intermediate (155-195 cases), and high (> 195 cases) volume, there were no significant linear relationships between risk-adjusted outcomes and operator terciles. No significant correlations were seen between individual PCI volume and risk-adjusted rates of mortality, bypass surgery, or the combined end point (P = .2, P = .35, and P = .95, respectively).

CONCLUSIONS

In contrast to US studies, there does not appear to be an association between PCI volume and outcomes in Ontario. These findings may be related to the high annual volumes of most operators and institutions within Ontario.

Is the volume-outcome relation still an issue in the era of PCI with systematic stenting? Results of the greater Paris area PCI registry

AIMS

In acute myocardial infarction (AMI), primary percutaneous transluminal angioplasty (PTCA) is the preferred option when it can be performed rapidly. Because of the limited access to high PTCA volume centres in some areas, it has been suggested that PTCA could be performed in low-volume centres on AMI patients. Little data exist on the validity of this strategy in modern era PTCA.

METHODS AND RESULTS

The Greater Paris area comprises 11 million inhabitants and accounts for 18% of the French population. In 2001, the hospital agency of the Greater Paris area set up a registry of all PTCAs performed in this region. Data from 2001 and 2002 was analysed. Hospitals performing <400 PTCAs per year were classified as low-volume. A case-control analysis (propensity score) compared in-hospital mortality in low- and high-volume centres. A total of 37 848 angioplasty procedures were performed in 44 centres during the study period; 24.7% were performed in low-volume centres. A non-statistically significant trend towards reduced in-hospital mortality was noted in high-volume centres as opposed to low-volume centres: 2.01 vs. 2.42%, P = 0.057. In-hospital mortality rates were significantly different in the sub-group of emergency procedures: 6.75% in high- vs. 8.54% in low-volume centres, P = 0.028. No difference was noted between low- and high-volume centres in non-emergency procedures (0.62 vs. 0.62%, P = 0.99).

CONCLUSION

In the era of modern stenting, a clear inverse relationship exists between hospital PTCA volume and in-hospital mortality after emergency procedures. Tolerance of low-volume thresholds for angioplasty centres with the purpose of providing primary PTCA in AMI should not be recommended, even in underserved areas.

Out-of-hospital endotracheal intubation: where are we?

While remaining prominent in paramedic care and beneficial to some patients, out-of-hospital endotracheal intubation has not clearly improved survival or reduced morbidity from critical illness or injury when studied more broadly. Recent studies identify equivocal or unfavorable clinical effects, adverse events and errors, interaction with other important resuscitation interventions, and challenges in providing and maintaining procedural skill. We provide an overview of current data evaluating the overall effectiveness, safety, and feasibility of paramedic out-of-hospital endotracheal intubation. These studies highlight our limited understanding of out-of-hospital endotracheal intubation and the need for new strategies to improve airway support in the out-of-hospital setting.

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.

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.

The relationship between hospital or operator volume and outcomes of coronary patients undergoing percutaneous coronary interventions

The relationship between volume and outcome in medicine has been intensively investigated in the last few decades. The large amount of accumulated data demonstrates that for many surgical or non-surgical procedures and medical conditions, patients being treated in high-volume hospitals or by high-volume physicians have lower mortality rates and better quality of life compared to those treated by low-volume hospitals or by low-volume physicians. Although the degree of the relationship between high volume and better outcome varies, it is persistent across a wide range of procedures and conditions. Percutaneous coronary interventions (PCIs) have an important impact on public health, given the frequency of coronary heart disease for which these procedures are performed. Studies carried out before and after the advent of stents on the relationship between volume and outcome for PCIs have almost consistently reported that performance of PCIs in high-volume institutions or by high-volume operators is associated with improved outcomes for patients, regardless of the specific indication for PCI. For those procedures for which a relationship between high volume and better outcome has been clearly demonstrated, patients as well as their referring physicians should be informed that patients can benefit both in terms of reduced mortality and improved quality of life if they are treated by high-volume health care providers. Consequently, for these procedures, a health care policy aiming at their concentration in high-volume institutions should be strongly considered.

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.

Impact of interventionalist volume, experience, and board certification on coronary angioplasty outcomes in the era of stenting

It has been suggested that percutaneous coronary intervention (PCI) by high-volume operators may be associated with better outcomes. However, the relation between operator and outcome is confounded by hospital caseloads of PCI, with busier hospitals generally having better outcomes. We assessed the effect of operator characteristics (volume of PCI, years in practice, and board certification status) on contemporary outcomes of PCI in a busy center with high-volume operators. Between 1999 and 2001, 12,293 PCIs were performed at our center by 28 interventionalists. Patients' clinical risk was assessed with the previously validated Beaumont PCI Risk Score. Operators were classified as producing low, medium, or high volume (tertiles of annual PCI volume < or =92, 93 to 140, or >140, respectively), as less, medium, or great experience (tertiles of years in practice < or =8, 9 to 14, or >14 years, respectively), and board certified (68%) or not. In-hospital death rate and a composite end point (death, coronary artery bypass graft surgery, myocardial infarction, or stroke) occurred in 0.99% and 2.59% of patients, respectively. Operator volume, experience, and board certification showed no univariate or multivariate relation with the study end points. The Beaumont PCI Risk Score showed a strong independent relation with in-hospital death rate (adjusted odds ratio 1.37, 95% confidence interval 1.31 to 1.43, p <0.0001) and composite end point (odds ratio 1.19, 95% confidence interval 1.16 to 1.22, p <0.0001). We conclude that, in contemporary PCI practice at a large center with high-volume operators, in-hospital outcomes are not affected by operator volume, experience, or board certification. Rather, patients' clinical risk score is the overriding determinant of clinical outcomes. Our findings emphasize the power of a well-organized high-volume system to minimize the impact of operator factors on outcomes of PCI.

Threshold volumes associated with higher survival in health care: a systematic review

BACKGROUND

To date, systematic reviews on the relationship between the volume of specific diagnoses and procedures and patient outcomes have several limitations, including the omission of the most recent publications.

OBJECTIVE

To investigate the relationship between hospital and physician volume and patient mortality rate for all diagnoses and interventions in health care.

RESEARCH DESIGN

Medline and the Cochrane Library were searched from January 1990 to December 2000 for all studies published in Dutch, English, French, German, and Italian. The following Boolean search statement was used: hospitals AND volume AND (outcome OR mortality OR quality). Studies were included in which patient enrollment ended within 10 years of the current study and that were adjusted for case-mix. For each diagnosis and intervention, the study most likely to provide an unbiased estimate of the effect of volume on mortality rate was identified using a specific algorithm (best study).

RESULTS

A total of 34 diagnoses and interventions with at least one qualifying study on the volume-outcome relationship were identified. The summary odds ratio/relative risk for the best studies on hospital and physician volume were 0.87 (95% confidence interval [CI], 0.85-0.89) and 0.87 (95% CI, 0.81-0.94), respectively. From the best studies on hospital volume, 48.5% (16 of 33) were published either in 1999 or 2000.

CONCLUSIONS

There is evidence for a volume-mortality relationship for hospitals and physicians. The use of appropriate methods for analyzing additional diagnoses and interventions as well as a continuous systematic evaluation of the evidence is recommended.

Reperfusion in acute myocardial infarction: current concepts

Myocardial reperfusion is the treatment of choice in acute myocardial infarction. Pharmacological thrombolysis restores coronary artery patency in about two thirds of patients with acute myocardial infarction. However, mechanical reperfusion with primary angioplasty and stenting achieves higher patency rates with less complications, especially in high-risk patients. Adjunctive pharmacotherapy and new device technology may improve the outcome of primary angioplasty. Facilitated angioplasty using a combination of half-dose thrombolysis, platelet glycoprotein IIb/IIIa antagonists, and early intervention, appears to be a promising strategy for the treatment of acute myocardial infarction in the modern era. The efficacy and safety of this approach are currently evaluated in several ongoing trials.

Assessing quality in the cardiac catheterization laboratory

Quality assurance and improvement have increasingly been the focus of health care providers, third-party payers, and patients. Because cardiovascular procedures are common, easily identifiable with claims data, and account for a relatively large proportion of health care expenditures, particular attention has been paid to quality assurance in the setting of the diagnostic and interventional cardiac catheterization laboratory. The structure, process, and outcomes domains of quality measurement in the interventional laboratory involve the maintenance of volume standards, the availability of surgical backup, consistent tracking of procedural outcomes and complications so they can be compared with national standards, and the application of evidence-based therapy. Quality assurance i the diagnostic laboratory revolves around the clinical proficiency of the operators, the maintenance and management of catheterization laboratory equipment, and the presence of a continuous quality improvement program. The evolution of interventional equipment and techniques along with the establishment of national registries has led to a gradual improvement in the quality of percutaneous coronary intervention. Given the dynamic nature of cardiology, adaptable quality assurance and quality improvement programs will remain the foundation of successful catheterization labs.

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.

Selective referrals in a 'hub and spoke' institutional setting: the case of coronary angioplasty procedures

We analyse the highly-regulated cardiovascular sector of the health service in the Italian region of Emilia Romagna: this sector is characterised by strict regulatory control and a great emphasis on co-ordination and co-operation between public and private producers. These features have been even more marked since 2000, due to the adoption of the 'hub and spoke' organisational model, whereby a close relationship of selective referral from the network of satellite cardiology units (spokes) to the six Cardiac Surgical Centres (hubs) has been developed, so as to concentrate high risk procedures in highly specialised units. We focus on coronary angioplasty procedures (PTCA) and examine relations among centres before and after the official introduction of this hierarchical system completed the regionalisation of cardiovascular services. Secondly, since earlier regional efforts to reconfigure cardiovascular care by sending referrals to a few major centres may already have produced a high level of co-ordination among units, we investigate what happens to the volume-effect advantage across hospital categories with regard to the likelihood of adverse results for PTCA. We used descriptive statistics and logistic regression models to assess the existence of selective referrals and the concentration of clinical complexity in more specialised centres. Figures were taken from a regional administrative database based on hospital discharge abstracts (SDO) for the period 1998-2000.

Relationship between coronary angioplasty laboratory volume and outcomes after hospital discharge

BACKGROUND

Although an inverse association has been established between short-term complications of percutaneous coronary interventions (PCIs) and the volume of angioplasty procedures performed by catheterization laboratories, no data are available on the association between laboratory volume and long-term outcomes.

METHODS

A cohort study of 25,222 patients undergoing PCI in 43 laboratories in Pennsylvania from October 1994 to December 1995 was performed by use of the Pennsylvania Health Care Cost Containment Council database. The association of laboratory volume with inhospital, 1-month, and 6-month events was estimated by use of multivariable analyses adjusting for patient and procedural characteristics.

RESULTS

Although a higher volume of procedures was associated with reduced inhospital coronary bypass ([CABG] 0.6 odds ratio [OR] for > or =400 vs <400 PCIs/year; 95% CI 0.4, 0.8), it was not associated with CABG occurring within 1 month after discharge (P =.71; OR 1.0, 95% CI 0.6, 1.7). Laboratory volume was also not significantly associated with postdischarge revascularization (PCI or CABG) at 1 month (P =.58; OR 1.1, 95% CI 0.8, 1.4) or 6 months (P =.47; OR 1.04, 95% CI 0.91, 1.19). In addition, laboratory volume was not associated with rates of myocardial infarction (P =.14), death (P =.28), or the combined outcome of PCI, CABG, myocardial infarction, or death (P =.90) at 1 month after hospital discharge.

CONCLUSIONS

Although our study confirmed the volume/complication relationship for inhospital CABG, it did not reveal an association between volume and postdischarge events. These results suggest that inhospital complications will remain the standard for assessing laboratory volume and that selective use of higher-volume laboratories may not improve long-term outcomes.

Condylomata acuminata (genital warts): patient demographics and treating physicians

BACKGROUND

Condylomata acuminata (genital warts), caused by the human papillomavirus, are common and sexually transmitted. However, the use of healthcare services for condylomata has never been characterized from a national probability sample study.

GOAL

To understand better the demographics of patients seen by physicians for this disorder.

STUDY DESIGN

Data from office visits for warts, both condylomata and noncondylomatous types, were obtained from the 1994 to 1998 National Ambulatory Medical Care Survey.

RESULTS

The age distribution of those treated for condylomata peaked in 20- to 39-year-olds, with more than 70% of patients in this age category. A younger and wider age distribution was seen in patients with noncondylomatous warts. Women accounted for 67% of the population seen for condylomata, whereas a more equal number of women and men were seen for noncondylomatous warts. Per capita healthcare use for condylomata was equal between blacks and whites, and whites had almost five times more per capita healthcare use than blacks for noncondylomatous warts. Obstetrician/gynecologists were the most commonly consulted physicians for condylomata. Per capita condylomata visits per physician were highest for obstetrician/gynecologists, dermatologists, and urologists, and lower for all other physicians.

CONCLUSIONS

The difference in age distribution between condylomata and noncondylomatous visits likely results from differing modes of transmission and age at first sexual contact. Females are more likely than males to use health care for condylomata, which may be attributable to increased prevalence, differences in treatment efficacy, differences in the gender frequency of genital health screenings, or psychosocial causes. Healthcare use for condylomata appears equal between blacks and whites. Patients with condylomata acuminata were most often seen by obstetrician/gynecologists, whereas patients with noncondylomatous warts most often consulted dermatologists. The fact that per capita condylomata visits per physician were highest for obstetrician/gynecologists, dermatologists, and urologists may imply that specialists in these fields have expertise in treating these patients.

Volume-outcome relation for physicians and hospitals performing angioplasty for acute myocardial infarction in New York state

BACKGROUND

An inverse relation exists between the number of coronary angioplasty procedures performed by physicians or hospitals and short-term mortality. It is not known, however, whether a similar relation holds for physicians and hospitals that perform primary angioplasty for acute myocardial infarction.

METHODS AND RESULTS

We analyzed data from the 1995 New York State Coronary Angioplasty Reporting System Registry to determine the relation between the number of primary angioplasty procedures performed by physicians and hospitals and in-hospital mortality. Patients who underwent angioplasty procedures within 23 hours of onset of acute myocardial infarction without preceding thrombolytic therapy were included (n=1342). In-hospital mortality was reduced 57% among patients who underwent primary angioplasty by high-volume as opposed to low-volume physicians (adjusted relative risk 0.43; 95% CI 0.21 to 0.83). When patients with acute myocardial infarction were treated with primary angioplasty in high-volume hospitals rather than low-volume institutions, the relative risk reduction for in-hospital mortality was 44% (adjusted relative risk 0.56; 95% CI 0.29 to 1.1). Compared with patients treated at low-volume hospitals by low-volume physicians, patients treated at high-volume hospitals by high-volume physicians had a 49% reduction in the risk of in-hospital mortality (adjusted relative risk 0.51; 95% CI 0.26 to 0.99).

CONCLUSIONS

Among hospitals in New York State, a higher volume of primary angioplasty procedures performed by physicians and/or hospitals was associated with a lower mortality rate.

The specialty of the treating physician affects the likelihood of tumor-free resection margins for basal cell carcinoma: results from a multi-institutional retrospective study

BACKGROUND

Basal cell carcinoma (BCC) is the most common cutaneous malignancy. Surgical experience and physician specialty may affect the outcome quality of surgical excision of BCC.

METHODS

We performed a multicenter retrospective study of BCC excisions submitted to the respective Departments of Pathology at 4 major university medical centers. Our outcome measure was presence of histologic evidence of tumor present in surgical margins of excision specimens (incomplete excision). Clinician experience was defined as the number of excisions that a clinician performed during the study interval. The analytic sample pool included 1459 tumors that met all inclusion and exclusion criteria. Analyses included univariate and multivariate techniques involving the entire sample and separate subsample analyses that excluded 2 outlying dermatologists.

RESULTS

Tumor was present at the surgical margins in 243 (16.6%) of 1459 specimens. A patient's sex, age, and tumor size were not significantly related to the presence of tumor in the surgical margin. Physician experience did not demonstrate a significant difference either in the entire sample (P <.09) or in the subsample analysis (P >.30). Tumors of the head and neck were more likely to be incompletely excised than truncal tumors in all the analyses (P <.03). Compared with dermatologists, otolaryngologists (P <.02) and plastic surgeons (P <.008) were more likely to incompletely excise tumors; however, subsample analysis for plastic surgeons found only a trend toward significance (P <.10). Dermatologists and general surgeons did not differ in the likelihood of performing an incomplete excision (P >.4).

CONCLUSION

The physician specialty may affect the quality of care in the surgical management of BCC.

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.

The volume of primary angioplasty procedures and survival after acute myocardial infarction. National Registry of Myocardial Infarction 2 Investigators

BACKGROUND

There is an inverse relation between mortality from cardiovascular causes and the number of elective cardiac procedures (coronary angioplasty, stenting, or coronary bypass surgery) performed by individual practitioners or hospitals. However, it is not known whether patients with acute myocardial infarction fare better at centers where more patients undergo primary angioplasty or thrombolytic therapy than at centers with lower volumes.

METHODS

We analyzed data from the National Registry of Myocardial Infarction to determine the relation between the number of patients receiving reperfusion therapy (primary angioplasty or thrombolytic therapy) and subsequent in-hospital mortality. A total of 450 hospitals were divided into quartiles according to the volume of primary angioplasty. Multiple logistic-regression models were used to determine whether the volume of primary angioplasty procedures was an independent predictor of in-hospital mortality among patients undergoing this procedure. Similar analyses were performed for patients receiving thrombolytic therapy at 516 hospitals.

RESULTS

In-hospital mortality was 28 percent lower among patients who underwent primary angioplasty at hospitals with the highest volume than among those who underwent angioplasty at hospitals with the lowest volume (adjusted relative risk, 0.72; 95 percent confidence interval, 0.60 to 0.87; P<0.001). This lower rate, which represented 2.0 fewer deaths per 100 patients treated, was independent of the total volume of patients with myocardial infarction at each hospital, year of admission, and use or nonuse of adjunctive pharmacologic therapies. There was no significant relation between the volume of thrombolytic interventions and in-hospital mortality among patients who received thrombolytic therapy (7.0 percent for patients in the highest-volume hospitals vs. 6.9 percent for those in the lowest-volume hospitals, P=0.36).

CONCLUSIONS

Among hospitals in the United States that have full interventional capabilities, a higher volume of angioplasty procedures is associated with a lower mortality rate among patients undergoing primary angioplasty, but there is no association between volume and mortality for thrombolytic therapy.

Debate: Unstable angina - When should we intervene?

The prognosis of patients who present with non-ST segment elevation acute coronary syndromes (ACS) is guarded. These patients can be risk-stratified on the basis of symptom complex, electrocardiographic ST segment depression, obvious hemodynamic compromise and particularly on the basis of serum troponin level. An elevated troponin level determines risk and also predicts the degree of benefit from treatment with either low molecular weight heparin or platelet glycoprotein (GP) IIb/IIIa blockade. Higher risk patients should undergo early coronary angiography and myocardial revascularization as indicated and feasible. Although studies performed before the advent of coronary stenting and adjunctive platelet GP IIb/IIIa blockade suggested increased hazard for patients undergoing early intervention, recent experience cited herein supports an in-hospital and long-term clinical benefit for the aggressive approach. Here, I propose an algorithm for risk stratification and triage of appropriate patients for adjunctive pharmacotherapy and early revascularization.

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.

Relation between lesion characteristics and risk with percutaneous intervention in the stent and glycoprotein IIb/IIIa era: An analysis of results from 10,907 lesions and proposal for new classification scheme

BACKGROUND

The currently used American College of Cardiology/American Heart Association lesion classification scheme dates from an era when balloon angioplasty was the only percutaneous treatment available and major complications occurred in approximately 7% of patients. Major advances in treatment options would suggest that this scheme may be outmoded, but the schemes that have been suggested to update lesion classification have not been widely accepted.

METHODS AND RESULTS

Four thousand one hundred eighty-one consecutive patients (6,676 lesions) formed a training set and 2,146 patients (4,231 lesions) formed a validation set treated from 1995 to 1997 at a single center used by 3 hospital groups. Twenty-seven pretreatment candidate variables were analyzed with the use of stepwise proportional logistic regression, and 9 (nonchronic total occlusion with TIMI flow 0, degenerated vein graft, vein graft age >10 years, lesion length >/= 10 mm, severe calcium, lesion irregularity, large filling defect, angulated >/= 45 degrees plus calcium, and eccentricity) were independently correlated (P<0.05) with ranked adverse outcome (death, Q-wave or creatine kinase >/= 3x normal myocardial infarction, or emergency coronary artery bypass grafting>>creatine kinase 2 to 3x myocardial infarction>>possibly related to non-Q-wave myocardial infarction>>no complication). A scheme based on these findings and the old American College of Cardiology/American Heart Association scheme were found to have c-statistics in the validation set of 0.672 and 0.620 (P = 0.010 vs old scheme), respectively.

CONCLUSIONS

Appreciation of these contemporary risk factors for complications of coronary intervention may assist in patient selection and in risk adjustment for comparison of outcomes between providers.

Prognostic value of the modified american college of Cardiology/American heart association stenosis morphology classification for long-term angiographic and clinical outcome after coronary stent placement

Background-The modified American College of Cardiology/American Heart Association (ACC/AHA) lesion morphology criteria are predictive of early outcome after various coronary catheter interventions. Their potential prognostic value after stent implantation and, in particular, for restenosis and long-term clinical outcome has not been studied. We assessed the prognostic value of the modified ACC/AHA criteria for the long-term angiographic and clinical outcome of patients after coronary stenting. Methods and Results-This study includes 2944 consecutive patients with symptomatic coronary artery disease treated with coronary stent placement. Modified ACC/AHA lesion morphology criteria were used to qualitatively assess the angiograms; type A and B1 lesions were categorized as simple, and type B2 and C lesions were designated complex. Primary end points were angiographic restenosis and 1-year event-free survival. Restenosis rate was 33.2% in complex lesions and 24.9% in simple lesions (P<0.001). It was 21. 7% for type A, 26.3% for type B1, 33.7% for type B2, and 32.6% for type C lesions. One-year event-free survival was 75.6% for patients with complex lesions and 81.1% for patients with simple lesions (P<0. 001). It was 85.2% for patients with type A, 79.4% for type B1, 75. 9% for type B2, and 75.2% type C lesions. The higher risk for restenosis and an adverse outcome associated with complex lesions was also maintained after multivariate adjustment for other clinical and angiographic characteristics. Conclusions-The modified ACC/AHA lesion morphology scheme has significant prognostic value for the outcome of patients after coronary stent placement. Lesion morphology is able to influence the restenosis process and thus the entire 1-year clinical course of these patients.