Incidence of Bacterial Endocarditis in Ventricular Septal Defects

Abstract

In summary, the population figures presented place the risk of bacterial endocarditis for cases of ventricular septal defect in the 5 to 14-year age group as 1 in 470 patient years, or 2.1 per 100 cases in 10 years. The estimated risks for the 5-year-old and 15-year-old patient up to the age of 70 years would be 13.6% and 11.5% respectively. In the city of Toronto, only four cases were seen in 10 years in the general population of over half a million, while in metropolitan Toronto with the population of 1.3 million, eight cases were seen in a similar period. If the clinical experiences of the various authors reported in the literature are pooled with that at The Hospital for Sick Children in Toronto, one would have 21 cases of bacterial endocarditis in 11,328 patient years. This would place the incidence as approximately 1 in 500 patient years. It is suggested that the surgery for ventricular septal defect may itself initiate bacterial endocarditis as noted in three of our cases. On the basis of the available data, there is insufficient evidence to designate the risk of future bacterial endocarditis as an adequate reason for surgical closure of the defect.