RISK OF INFECTIVE ENDOCARDITIS AFTER INTRACARDIAC SURGERY

The most important risk of infective endocarditis (IE) after intracardiac surgery is after prosthetic valve replacement. In the recent literature, the prevalence of prosthetic IE depends on the criteria of definition of IE and on the interval between surgery and IE. The rate of early IE ranges from 0.4 to 1.3 %, and the rate of late IE is less than 0.5 %/pt/year. The prevalence of prosthetic IE does not depend on the type of prosthesis, nor on its location; it increases in case of multivalvular replacement. Staphyloccoci are the most usual micro-organisms in early IE; in late IE, the spectrum of microorganisms is the same as in native valve IE. The portal of entry is more often found in early than in late prosthetic IE (50 %). The risk of IE in patients operated on for congenital heart disease is very low after repair of left-to-right intracardiac shunts and after pulmonary or aortic valvotomy. It is higher in patients operated on for tetralogy of Fallot or for complex cyanotic congenital heart disease, chiefly in case of residual interventricular defect or after palliative surgery (systemic-pulmonary anastomosis). The risk of IE on intracardiac electrodes is low, as the risk after interventional cardiology procedures or after heart transplantation. Prophylaxis of IE is essential after prosthetic valve replacement, and after surgery for tetralogy of Fallot or for complex malformations.