Objective: Mortality in active infective endocarditis (AIE) is substantial and reinfection can strongly influence outcome. Assessment of factors influencing mortality is important. We studied 108 (33%) patients suffering from root abscess out of a total of 327 AIE patients admitted to the Deutsches Herzzentrum Berlin for surgical treatment between 1996 and 2003. Among them were 53 (25.5% of all patients) who were diagnosed as having secondary infective mitral valve disease (SMVD). Mean age was 53+/-14.2 years; there were 37 men and 16 women.
Methods: Risk factors were assessed on the basis of clinical, hemodynamic, echocardiographic and surgical information. Mean follow-up was 325+/-251 days with complete echocardiographic examination performed in patients with double valve surgery. The differences between groups were analyzed using Student's t-test. Multivariate analysis for the whole group suffering from abscess was performed to identify independent factors influencing mortality.
Results: In 19 (35.8%) patients suffering from SMVD mitral valve reconstruction was undertaken and mitral valve replacement was performed in 34 (64.2%) patients. There were 27 patients treated with a Shelhigh prosthesis: 18 with double valve replacement (both Shelhigh) and nine with an aortic Shelhigh prosthesis and concomitant mitral valve reconstruction. Homografts were used in 17 patients, with mitral reconstruction in 10 and a stented mitral prosthesis in seven. In nine cases two stented valve prostheses were used. The calculated mean Doppler gradient for homografts and Shelhigh in aortic position was 12 (+/-5.7) and 15 (+/-4.6), respectively (NS). The following predisposing factors for mortality were assessed: severe damage of aortic annulus (OR 4.65, CI 1.22-17.1, P=0.0159); septic shock (OR 3.44, CI 0.85-13.9, P=0.07) and poor ejection fraction (<40%), and dilated LV.
Conclusions: Excessive mortality reaching 29% was noted in patients suffering from AIE with aortic ring abscess and SMVD requiring double valve surgery. Double valve surgery with semi-stented Dacron-free valve prostheses is associated with a low rate of reinfection and good function of the implants. The most potent independent risk factors for death were septic shock and severe aortic root destruction.