Surgery for infective endocarditis: determinate factors in the outcome

AIM: The appropriate operative procedures for treatment of infective endocarditis (IE) are still controversial. The authors reviewed their own operative results focusing on preoperative risk factors, intraoperative findings and operative procedures. METHODS: The authors reviewed the cases of 40 adult patients who had undergone surgery since 1999. The mean age of patients was 58 years ranging from 31 to 78 including 30 males and 10 females. Thirty-three patients had native valve endocarditis (NVE) and the remaining seven patients had prosthetic valve endocarditis (PVE). Diseased lesions were located in the mitral valve (MV) in 21 patients, aortic valve in 15 and mitral plus aortic valves in four. Twenty-eight patients (70%) were operated on during the active phase of IE. Streptococcus, Staphyrococcus and Enterococcus species were predominant in the bacterial examination. RESULTS: Active vegetation was observed in 26 (65%) patients. Perforation of valve leaflets was observed in 11 (28%) cases. Changes of native MV leaflet were mild in 8 (40%) out of 20, which seemed to be reparable, while, changes of the native aortic valve leaflet were moderate to severe in 13 (87%) out of 15 patients. Valvular annuls were involved in the infection in 17 (43%) patients. Of the 33 NVE patients, prosthetic valve replacement was performed in 29 patients incduding 19 mitral and 15 aortic valves. MV plasty was performed in 4 patients. In seven PVE patients, prosthetic MV replacement was performed twice. In the aortic group, three patients underwent aortic root translocation, The Ross procedure and standard root replacement were performed respectively. Four patients died after surgery including one NVE case and three PVE cases. Three PVE patients who underwent aortic root translocation or the Ross procedure survived. The hospital mortality of NVE and PVE surgery was 3% and 43% (P<0.01), respectively. By univariant anlysis, there were no significant correlations between operative results and preoperative factors such as bacteria, infective phase, cardiac failure, renal failure, sepsis or brain morbidity. The only significant factor on hospital mortality was PVE. Three patients died of non-cardiac diseases during the follow-up period. CONCLUSION: Operative results of NVE were good after complete resection of infective sites including valve annulus. Both valve replacement and plasty were available for NVE patients. In PVE, new strategies are indispensable and aortic root translocation or the Ross procedure should be a treatment of choice.