Evaluating treatment options for patients with infective endocarditis: when is it the right time for surgery?

Evolution of epidemiological characteristics of infective endocarditis in Greece

OBJECTIVE

The clinical profile, management and outcome of infective endocarditis (IE) may be influenced by socioeconomic issues.

METHODS

A nationwide prospective study evaluated IE during the era of deep economic crisis in Greece. Epidemiological data and factors associated with 60-day mortality were analyzed through descriptive statistics, logistic and Cox-regression models.

RESULTS

Among 224 patients (male 72.3%, mean age 62.4 years), Staphylococcus aureus (n = 62; methicillin-resistant S. aureus (MRSA) 33.8%) predominated in the young without impact on mortality (p = 0.593), whilst Enterococci (n = 36) predominated in the elderly. Complications of IE were associated with mortality: heart failure [OR 2.415 (95% CI: 1.159-5.029), p = 0.019], stroke [OR 3.206 (95% CI: 1.190-8.632), p = 0.018] and acute kidney injury [OR 2.283 (95% CI: 1.085-4.805), p = 0.029]. A 60-day survival benefit was solely related to cardiac surgery for IE during hospitalization [HR 0.386 (95% CI: 0.165-0.903), p = 0.028] and compliance with antimicrobial treatment guidelines [HR 0.487 (95% CI: 0.259-0.916), p = 0.026]. Compared with a previous country cohort study, history of rheumatic fever and native valve predisposition had declined, whilst underlying renal disease and right-sided IE had increased (p < 0.0001); HIV infection had emerged (p = 0.002). No difference in rates of surgery and outcome was assessed.

CONCLUSIONS

A country-wide survey of IE highlighted emergence of HIV, right-sided IE and predominance of MRSA in the youth during a severe socioeconomic crisis. Compliance with treatment guidelines promoted survival.

Mortality and timing of surgery in the left-sided infective endocarditis: an Italian multicentre study

OBJECTIVES

Observational studies on early surgery in infective endocarditis have conflicting results. This study aims to compare the treatment strategies for early surgery (within 2 weeks of diagnosis) and late surgery/medical therapy in terms of survival among patients with the left-sided infective endocarditis.

METHODS

This study included patients with the left-sided infective endocarditis registered between 2006 and 2010 in the Italian Registry of Infective Endocarditis (RIEI). A Cox proportional hazards model was used to estimate the effect of these treatment strategies on overall survival and included sociodemographic and clinical characteristics associated with treatment, risk factors for mortality and early surgery as a time-dependent covariate to avoid indication and immortal time biases.

RESULTS

Among the 502 patients included, 184 (36.7%) underwent early surgery. Of the remaining 318 patients, 138 underwent late surgery. The early surgery group had fewer patients with comorbidities and with enterococcus as the causative microorganism, but this group had more complicated cardiac conditions. No difference in mortality risk was estimated between the treatment groups including early surgery as time-dependent variables (adjusted hazard ratio  = 0.95, 95% confidence interval 0.55-1.63), while a distorted and overestimated beneficial effect of surgery was estimated considering surgery as a non-time-dependent variable (adjusted hazard ratio 0.41, 95% confidence interval 0.25-0.70).

CONCLUSIONS

Our study did not confirm a better overall survival in patients undergoing early surgery. However, even with the use of statistical techniques to control biases, we could not draw definitive conclusions that early surgery is not beneficial. Our results need to be assessed by randomized trials before any changes in clinical practice can be recommended.