Objective: To evaluate the acceptance rate of the 2007 American Heart Association (AHA) prophylactic protocol by the patients for whom the need for prophylaxis for infective endocarditis was downgraded. Method and Materials: A survey among patients was conducted. Patients were included if they had to receive antibiotic prophylaxis prior to dental treatment according to the 1997 AHA protocol and did not require antibiotic prophylaxis prior to dental treatment according to the 2007 AHA guidelines. The perception of the patients and their physicians to the change was analyzed. Possible contributing parameters were assessed. Results: The slight decrease in the rate of acceptance with an increase in time since the AHA publication demonstrated by the logistic regression (odds ratio, 0.93; 95% CI, 0.79 to 1.10) was not statistically significant (P = .41). Parameters related to lower patient acceptance rates were invasiveness of dental treatment and the type of dental setting (P = .046 and .001, respectively). Parameters that were found not to affect the patient acceptance rate were the severity of cardiac condition and a durable history of dental treatments in the same institute (P = .06 and .26, respectively). Conclusions: Sixteen months after publication of the 2007 AHA guidelines, the acceptance rate of the protocol is moderate to high. Reasons for this partial acceptance are discussed. Palabras clave: acceptance, American Heart Association, endocarditis, prophylaxis