Author + information
- Received April 12, 2011
- Revision received May 9, 2011
- Accepted May 14, 2011
- Published online September 1, 2011.
- Lisa Bergersen, MD, MPH⁎,⁎ (, )
- Kimberlee Gauvreau, ScD⁎,
- Susan R. Foerster, MD†,
- Audrey C. Marshall, MD⁎,
- Doff B. McElhinney, MD⁎,
- Robert H. Beekman III, MD‡,
- Russel Hirsch, MD‡,
- Jacqueline Kreutzer, MD§,
- David Balzer, MD†,
- Julie Vincent, MD∥,
- William E. Hellenbrand, MD∥,
- Ralf Holzer, MD¶,
- John P. Cheatham, MD¶,
- John W. Moore, MD#,
- Grant Burch, MD⁎⁎,
- Laurie Armsby, MD⁎⁎,
- James E. Lock, MD⁎ and
- Kathy J. Jenkins, MD, MPH⁎
- ↵⁎Reprint requests and correspondence:
Dr. Lisa Bergersen, Department of Cardiology, The Children's Hospital, Longwood Avenue, Boston, Massachusetts
Objectives This study sought to develop a method to adjust for case mix complexity in catheterization for congenital heart disease to allow equitable comparisons of adverse event (AE) rates.
Background The C3PO (Congenital Cardiac Catheterization Project on Outcomes) has been prospectively collecting data using a Web-based data entry tool on all catheterization cases at 8 pediatric institutions since 2007.
Methods A multivariable logistic regression model with high-severity AE outcome was built using a random sample of 75% of cases in the multicenter cohort; the models were assessed in the remaining 25%. Model discrimination was assessed by the C-statistic and calibration with Hosmer-Lemeshow test. The final models were used to calculate standardized AE ratios.
Results Between August 2007 and December 2009, 9,362 cases were recorded at 8 pediatric institutions of which high-severity events occurred in 454 cases (5%). Assessment of empirical data yielded 4 independent indicators of hemodynamic vulnerability. Final multivariable models included procedure type risk category (odds ratios [OR] for category: 2 = 2.4, 3 = 4.9, 4 = 7.6, all p < 0.001), number of hemodynamic indicators (OR for 1 indicator = 1.5, ≥2 = 1.8, p = 0.005 and p < 0.001), and age <1 year (OR: 1.3, p = 0.04), C-statistic 0.737, and Hosmer-Lemeshow test p = 0.74. Models performed well in the validation dataset, C-statistic 0.734. Institutional event rates ranged from 1.91% to 7.37% and standardized AE ratios ranged from 0.61 to 1.41.
Conclusions Using CHARM (Catheterization for Congenital Heart Disease Adjustment for Risk Method) to adjust for case mix complexity should allow comparisons of AE among institutions performing catheterization for congenital heart disease.
A Web-based application for data entry was developed in 2006 with funding support from the Children's Heart Foundation (Chicago, Illinois). The application was deployed on a Microsoft Internet Information Server obtained with funding support from the American Heart Association. The American Heart Association Physicians Roundtable Award (AHA-PRA) provides support for the project and career development plan for Dr. Bergersen (2006 to 2010). The Keane Operating Fund at The Children's Hospital in Boston provided the resources necessary to perform site visits and independent audits. Drs. McElhinney and Vincent are consultants and proctors for Medtronic. Drs. Beekman and Balzer are proctors for AGA Medical Inc. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received April 12, 2011.
- Revision received May 9, 2011.
- Accepted May 14, 2011.
- American College of Cardiology Foundation