Hospital risk factors for bovine pericardial bioprosthesis valve implantation

Identification of preoperative heart valve surgery risk factors aim to improve surgical outcomes with the possibility to offset conditions related to increased morbidity and mortality.

Intent of this study is to identify hospital risk factors in patients undergoing bovine pericardial bioprosthesis implantation.

Retrospective study including 703 consecutive patients who underwent implantation of at least one St. Jude Medical-Biocor bovine pericardial bioprosthesis between September 1991 and December 2005 at the Rio Grande do Sul Cardiology Institute; 392 were aortic, 250 were mitral and 61 were mitroaortic. Characteristics analyzed were gender, age, body mass index, NYHA (New York Heart Association) functional class, ejection fraction, valve lesions, systemic hypertension, diabetes mellitus, kidney function, arrhythmias, prior heart surgery, coronary artery bypass graft, tricuspid valve surgery and elective, urgent or emergency surgery. Main outcome was in-hospital mortality. Relationship between risk factors and in-hospital mortality was analyzed using logistic regression.

Were 101 (14.3%) in-hospital deaths. Characteristics with significant relationship to increased mortality were female gender (p<0.001), age over 70 years (p=0.004), atrial fibrillation (p=0.006), diabetes mellitus (p=0.043), creatinine > 2.4 mg/dl (p=0.004), functional class IV (p<0.001), mitral valve lesion (p<0.001), previous heart surgery (p=0.005), tricuspid valve surgery (p<0.001) and emergency surgery (p<0.001).

Mortality rate observed is accepted by literature and is justifiable due to the high prevalence of risk factors, showing an increased significance level for female gender, age above 70, functional class IV, tricuspid valve repairs and emergency surgery. Offsetting these factors could contribute to reduced in-hospital mortality for valve surgery.