Background: Infective endocarditis carries a high risk of morbidity and mortality. Rapid diagnosis, effective treatment, and prompt recognition of complications are essential to good patient outcome. Aim: The study aimed to evaluate health outcomes among patients with acute infective endocarditis linked to nurses’ performance along with standard care protocol. Design: A quasi- experimental research design was utilized in this study. Setting: The study was carried out in Coronary Care Unit at Benha University Hospital. Sample: Convenient sample of (50) nurses and purposive sample of (66) adult conscious patients. Tools: three tools were used, Tool (1): Self-administered questionnaire to assess nurses' knowledge concerning acute infective endocarditis, tool (2): Observational checklist to assess nurses' practice regarding acute infective endocarditis patients, Tool (3): Structured interviewing questionnaire to assess patients’ health outcomes. Results: The study revealed that 20.0 % of studied nurses had satisfactory level of total knowledge, moreover, 15.6 % of studied nurses had satisfactory level of total practice about nursing care for patient with acute infective endocarditis pre standard care protocol, which improved immediately and post one month periods of implementation to become (71.1%, 64.4 %, respectively) with a statistically significant differences at (p≤0.05). Also, incidence of complications pre standard care protocol was among 96.7% of patients, which slightly declined immediately and post one month periods of implementation to become (86.7%, 50%, respectively). Conclusion: Providing nursing education has been shown to be effective on nurses' performance regarding care of patient with acute infective endocarditis. Recommendation: Continuous education and training of nurses and patients regarding acute infective endocarditis.