In the same cohort, patients who underwent generator replacement at a center that did 250 or more procedures per year were 45% less likely to have any type of complication, compared with patients who were treated at centers that did fewer procedures each year, said Dr. Mela, director of the pacemaker laboratory at Massachusetts General Hospital in Boston.
Other variables examined that did not have a significant bearing on complication rates included age, gender, number and severity of comorbidities as measured by the Charlson Comorbidity Index, specialty of the physician performing the procedure (electrophysiologist compared with nonelectrophysiologist), and type of practice (academic center compared with private hospital).
The analysis used data from the first arm of REPLACE, in which 1,031 patients were enrolled at 68 U.S. centers (34 academic and 34 private) during July 2007–March 2008, and tallied the number of complications during 6 months' follow-up. The researchers reported a 4% major complication rate, a 7.4% minor complication rate, and an overall complication rate of 10.9% at the annual meeting of the Heart Rhythm Society in Boston last May.
Subsequent analysis examined potential determinants of the complication rate. Patients with a pacemaker had a major complication rate of 2.3%, compared with a rate of 5.8% in patients with an ICD (the registry included roughly equal numbers of patients with each device type). The 68 sites had a median annual procedure volume of 250. High-volume sites had an overall complication rate of 8.6%; low-volume centers had an overall rate of 14.9%.
Dr. Mela said that she has received honoraria from Boston Scientific, Medtronic, and St. Jude Medical.