Combined cardiac catheterization for uncomplicated ischemic heart disease in a medicare population

PURPOSE: Experts recommend left heart catheterization alone to evaluate uncomplicated ischemic heart disease, reserving right heart catheterization for specific indications. Yet some centers routinely perform combined cardiac catheterization (left heart catheterization and right heart catheterization together). SUBJECTS AND METHODS: Using 1992–1993 Pennsylvania Medicare claims for cardiac catheterizations (n = 41,180), we examined rates of combined cardiac catheterization for patients with uncomplicated ischemic heart disease for each hospital (n = 73) that performed catheterizations. We compared combined cardiac catheterization rates among hospitals and developed a multivariable model to identify hospital characteristics associated with high combined cardiac catheterization rates. A random sample of cases from the 10 hospitals with the highest combined cardiac catheterization rates were reviewed to determine justification, complications, and results of combined cardiac catheterization. RESULTS: Of the 41,180 cardiac catheterizations, 14,177 (34%) were combined procedures. Among hospitals, combined cardiac catheterization rates varied from 2% to 98%. Hospital characteristics associated with high combined cardiac catheterization rates included having a cardiology fellowship program (relative risk [RR] 1.7, 95% confidence interval [CI] 1.1–2.7), location in eastern Pennsylvania (RR 2.5, 95% CI: 1.8–3.5), and volume of catheterizations performed (RR 0.95, 95% CI: 0.91–0.99/100 procedures). For reviewed cases, the most common justification for combined cardiac catheterization was planned revascularization (44%), which is not a specific indication. Only 49% of cases had at least one specific indication for right heart catheterization (range by hospital, 30%–74%). The abnormal findings on the right heart catheterization rarely appeared to change management. CONCLUSION: There is wide variation in the practice of combined cardiac catheterization, which appears to be related to teaching status and geographic location. The most common justification for the procedure was planned revascularization, which is not one of the specific indications supported by current literature.