JAMA: Cardiac device infective endocarditis leads to infection, mortality
“Cardiac device infection is a serious, emerging disease with a 210 percent increase in incidence between 1993 and 2008,” Eugene Athan, MD, of Barwon Health in Geelong, Australia, and colleagues wrote. “In-hospital charges for this complication are estimated to be at least U.S. $146,000 per case. Cardiac device infective endocarditis (CDIE) in particular has a substantially higher mortality rate than cardiac device infection without endocarditis.”
To better understand the implications of CDIE, Athan et al conducted a prospective cohort study using data from the International Collaboration on Endocarditis—Prospective Cohort Study (ICE-PCS). The study was conducted between June 2000 and August 2006 at 61 sites.
The researchers used in-hospital and one-year mortality rates as the study’s primary endpoint. All patients who were enrolled had endocarditis defined by Duke endocarditis criteria.
Of the total 2,760 patients, 177 were diagnosed with definite infective endocarditis. Of those with definite endocarditis, 152 had pacemakers, 21 had implantable cardioverter-defibrillators and four had an unspecified device. The majority of CDIE patients were men, had a median age of 71.2 and had diabetes. Blood cultures were positive in 149 patients and most were staphylococcal-related.
The researchers found valve infection to be present in 66 patients and echocardiographic detection of valvular vegetations in 63 patients. The researchers performed lead and device removal in 141 of the 177 endocarditis patients during the index hospitalization. Of the 66 patients with concomitant valve infection, 30 underwent valve surgery during index hospitalization. Twenty-six CDIE patients died during index hospitalization (18 of 141 who underwent device removal and eight of 34 who did not).
Fifteen deaths were reported between discharge and one-year follow-up. Of the 177 CDIE patients, 126 were alive at one year, 41 had died and 10 were lost to follow-up.
The authors concluded that patients who underwent device removal at index hospitalization saw improved one-year survival rates. Eighty-one patients with defined CDIE had healthcare-associated infections. Of those 81 patients, 61 had nosocomial and 20 had nonnosocomial infections. Patients with healthcare-acquired infections were associated with intravascular access and hemodialysis, which occurred more frequently in patients referred from other facilities.
Data showed that in-hospital mortality was lower in CDIE patients compared to in-hospital mortality rates of patients without cardiac devices who had native-valve or prosthetic valve staphylococcal infective endocarditis (18.6 percent vs. 22.4 percent vs. 31.3 percent).
“Cardiac device infective endocarditis accounted for 6.4 percent of all cases of definite infective endocarditis,” the authors wrote. “The high percentage of patients with healthcare-associated CDIE reiterates the significant recent epidemiologic trend and prognostic influence on survival previously described in both native- and prosthetic-valve infective endocarditis.”
Currently, the American Heart Association (AHA) recommends complete device and lead removal for patients who have definite infection as evidenced by valvular vegetations, lead vegetations or both, the authors wrote. In the current study, however, device removal was not found to be linked with improved in-hospital survival, but it did lead to significantly higher one-year survival.
“The presence of concomitant valve infection was associated with increased mortality at one year, regardless of device removal,” the authors wrote. “This finding suggests an important additional risk associated with CDIE and an influence on its outcome.”
Athan et al concluded that CDIE patients with or without concomitant valve infection could benefit from a multidisciplinary approach to management that includes cardiologists, infectious disease specialists and cardiac surgeons. This approach could improve long-term outcomes, they offered.
“In conclusion, CDIE, similar to native- and prosthetic-valve endocarditis, is significantly influenced by healthcare interventions in its development, microbiology and outcome,” they concluded. “Given that numbers of cardiovascular implantable electronic devices placed are increasing rapidly, further studies on the prevention and treatment of this serious complication are needed.”