1. © 2010, American Heart Association. All rights Association of Hospital Primary Angioplasty Volume in ST-Segment Elevation Myocardial Infarction With Quality and Outcomes Dharam J. Kumbhani, MD, SM; Christopher P. Cannon, MD; Gregg C. Fonarow, MD; Li Liang, PhD; Arman T. Askari, MD; W. Frank Peacock, MD; Eric D. Peterson, MD, MPH; Deepak L. Bhatt, MD, MPH Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

2. © 2010, American Heart Association. All rights Background Several studies have demonstrated an inverse relationship between hospital primary angioplasty volume and mortality in patients presenting with ST-segment elevation myocardial infarction (STEMI). Analysis of data by the National Registry of Myocardial Infarction has shown that high primary angioplasty volume hospitals (33 procedures per year) had a 28% lower in-hospital mortality compared with low primary angioplasty volume hospitals (5-11 procedures per year). Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

3. © 2010, American Heart Association. All rights Introduction Current American College of Cardiology/American Heart Association (ACC/AHA) guidelines for the management of patients with STEMI recommend that primary angioplasty in patients with STEMI be conducted by cardiac catheterization laboratories performing at least 36 primary angioplasties a year, as well as at least 200 total angioplasties a year. Despite earlier studies establishing an inverse relationship between hospital volume and mortality after primary angioplasty for patients presenting with ST-segment elevation myocardial infarction (STEMI), contemporary data are lacking. Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

4. © 2010, American Heart Association. All rights Objective The purpose of the research is to assess the relationship between hospital primary angioplasty volume and outcomes and quality of care measures in patients presenting with STEMI using data from GWTG-CAD national database. Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

5. © 2010, American Heart Association. All rights Methods An observational analysis of data on 29,513 patients presenting with STEMI and undergoing primary angioplasty in the GWTG registry. Patients were treated between July 5, 2001, and December 31, 2007, at 166 angioplasty-capable hospitals across the United States. Hospitals were divided into tertiles (36 procedures per year, 36-70 procedures per year, and 70 procedures per year) based on their annual primary angioplasty volume. The main outcome measures include the following: Door-to-balloon (DTB) times, length of hospital stay, adherence with evidence-based quality of care measures, and in-hospital mortality. Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

6. © 2010, American Heart Association. All rights Results Compared with low- and medium-volume centers, high-volume centers had better median DTB times (98 vs 90 vs 88 minutes, respectively; P for trend = 0.001). High-volume centers were more likely than low-volume centers to follow evidence-based guidelines at discharge. Length of stay was similar between the 3 groups (P for trend = 0.13). There was no significant difference in the crude mortality between the tertiles of volume (incidence rate, 3.9% vs 3.2% vs 3.0% for low, medium-, and high volume centers, respectively; P=0.26 and P=0.99 for low- and medium- vs high-volume hospitals, respectively). There was no significant association between hospital primary angioplasty volume and in-hospital mortality (adjusted odds ratio [OR], 1.22; 95% confidence interval [CI], 0.78-1.91; P=0.38 and adjusted OR, 1.14; 95% CI, 0.78-1.66; P=0.49 for low- and medium- vs high-volume hospitals, respectively). Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

7. © 2010, American Heart Association. All rights Limitations In addition to data being submitted voluntarily by participating hospitals, data were also collected by medical chart review and are thus dependent on the accuracy and completeness of documentation and abstraction. The GWTG-CAD is primarily a quality improvement registry and was not specifically designed to address the causal implication of hospital volume and mortality. The analysis reflects a subgroup analysis performed in the context of hospitals actively engaged in quality improvement, without a control set. Analysis of data from a control group of hospitals, not in the GWTG- CAD registry, with low primary angioplasty volume is thus necessary to strengthen our findings. There was an inability to adjust for individual operator volume. It is conceivable that low-volume hospitals may be performing as well as other hospitals because they have 1 or 2 high-volume operators. Finally, data on total ischemic (symptom to-door) time were not available. Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20

8. © 2010, American Heart Association. All rights Conclusion In a contemporary registry of patients with STEMI, higher-volume primary angioplasty centers compared with lower-volume centers were associated with shorter DTB times and greater use of evidence-based therapies, but not with adjusted in-hospital mortality or length of hospital stay. Further studies corroborating our findings with the use of stents and newer adjunctive pharmaco- therapy are necessary, including longer term follow-up. Kumbhani et al. JAMA, November 25, 2009, Vol 302, No. 20