Of the 20,663 cases, 15,305 (74%) were performed by surgeons, while 5,358 (26%) were performed by interventionalists. The mean patient age was 71 years, 61% were male, and 72% were white. The majority of cases (97%) were performed at teaching hospitals or at designated teaching institutions (61%). Unadjusted outcomes were similar between surgeons and interventionalists in terms of stroke (4.33% vs. 4.41%, respectively), MI (2.10% vs. 2.13%), and mortality (0.84% and 1.03%). When the researchers examined the percentage of stroke in 2008, “we saw an initial increase,” Dr. Sgroi said. “This may have been due to the amount of physicians who were performing carotid stenting.”
The researchers observed a statistically significant difference between the two groups in hospital length of stay as well as total hospital charges, with procedures performed by interventionalists resulting in a stay that was about one-third of a day longer, and about $3,000 more expensive.
Adjusted multivariate analysis demonstrated no statistically significant differences between the two types of clinicians in stroke, MI, or hospital mortality. However, hospital length of stay was significantly lower for procedures performed by surgeons, compared with interventionalists (2.81 vs. 3.08 days, respectively), as were total hospital charges ($48,088 vs. $51,719). “The cause of the difference is unclear and not discernible through the available data,” Dr. Sgroi said.
When he and his associates examined the 10-unit volume difference among centers, they found a statistically significant increase in the rate of stroke among lower-volume centers, but no other significant differences in outcomes were observed. “We believe that the rate of complications secondary to carotid stenting has stayed consistent from 2004 to 2011, despite advances in technology,” Dr. Sgroi concluded.
He acknowledged certain limitations of the study, including its retrospective design and the fact that data from the NIS account for only 20% of the U.S. population.
Dr. Sgroi reported having no financial disclosures.
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