Despite improvements in medical and surgical therapy, infective endocarditis (IE) is still associated with a severe prognosis and remains a therapeutic challenge. We aimed to evaluate the impact of a standardized diagnostic and therapeutic protocol on mortality and to correlate the outcome with compliance with our management-based protocol.
We conducted an observational before-after study that included 333 consecutive patients treated for IE at a referral center from 1991 to 2006, which was divided into 2 periods: period 1 (1991-2001), before implementation of our therapeutic protocol (n = 173), and period 2 (2002-2006), after implementation of our protocol (n = 160). Our protocol was created by a multidisciplinary task force including a sampling of biological specimens, the use of only 4 antimicrobial agents, a standardized duration of treatment, standardized surgical indications, and 1 year of close follow-up. Because our protocol was based on a local consensus by physicians and surgeons, it was not possible to randomize the study.
The 1-year mortality significantly decreased from 18.5% during period 1 to 8.2% during period 2 (hazard ratio, 0.41; 95% confidence interval, 0.21-0.79 [P = .008]). After multivariable analysis, the management during period 2 remained a strong protective factor (adjusted hazard ratio, 0.26; 95% confidence interval, 0.09-0.76 [P = .01]). During period 2, we observed a statistically significantly better compliance in antimicrobial therapy and fewer cases of renal failure. Deaths by embolic events and multiple organ failure syndrome also significantly decreased during period 2.
A dramatic reduction in mortality was observed during this study, suggesting that a management-based approach has a significant impact on IE outcome.