Background: There is no consensus regarding which risk factors influence the outcome of mitral valve replacement.
Aim: To study the effects of the referring health care system and other factors on the results of mitral replacement.
Patients and methods: We included 632 patients operated between 1990 and 2010 receiving the St Jude prosthesis. Patients were divided into three groups, group 1 composed by 180 patients coming from the Public System, group 2 composed by 182 patients coming from the University System and group 3 composed by 270 patients coming from the Private System.
Results: Overall operative mortality was 4.3%. There was no difference between groups in mortality. Factors responsible for operative mortality were: emergency operation (Odds Patio (OR): 5.6 P < 0.01) and left ventricular function (according to ejection fraction) grade III to IV (OR: 2.5 p = 0.048). Actuarial survival rates at 1, 5, 10, 15 and 20 years were 95%, 87%, 76%, 61% and 41%, respectively. Risk factors for long-term mortality were diabetes (OR: 3.3 p < 0.01), left ventricular function grades III-IV (OR: 2.6 p < 0.01), New York Heart Association functional class III to PV (OR: 2.1 p < 0.005) and male sex (OR: 1.5 p < 0.032).
Conclusions: Referring health care system and type of surgery do not constitute a risk factor for mitral replacement. Risk factors were: emergency surgery, ventricular function grades III-IV, diabetes, functional capacity class III-IV and male sex. Integration of public and private health care systems in a university hospital setting achieves excellent outcomes for complex pathology.