Long-Term Survival Benefits of Porcine versus Pericardial Bioprostheses in Elderly Patients Undergoing Isolated Aortic Valve Replacement: A 32-Year Study

Background: The elderly population is growing at an unprecedented rate. Aortic valve disease increases with age. Bioprostheses are the valves of choice for older patients; however, the optimal tissue valve remains undetermined. The purpose of this investigation was to perform a life-of-patient survival comparison of the prototypical porcine and pericardial prostheses in elderly patients. Methods: The study population (N = 1480) consisted of patients 65 years of age and older who underwent isolated aortic valve replacement from 1990 through 2005 with a CarpentierEdwards Porcine (n = 650) or Pericardial (n = 830) bioprosthesis. Propensity score-matched groups were created. Results: Valve selection was not associated with operative mortality. Survival estimates at 10 years were better for Pericardial (41.8%; 95% CI: 37.9 to 45.7) than Porcine (32.6%; 95% CI: 28.8 to 36.3); and 5.2% (95% CI: 3.2 to 7.1) versus 2.0%; (95% CI: 0.8 to 3.2) at 20 years (p < 0.001). E-value analysis found minimal influence of unknown study confounders. Factors associated with long-term mortality were porcine valve (p < 0.001), age (p < 0.001), diabetes mellitus (p < 0.001), preop renal insufficiency (p < 0.001), peripheral artery disease (p = 0.011), congestive heart failure (p = 0.003), New York Heart Association Class III or IV (p = 0.004), surgical history-reoperation (p = 0.012), transient ischemic attack (p = 0.009), prolonged ventilation (p = 0.010), postop renal insufficiency (p < 0.001), and atrial fibrillation (p = 0.009). The indexed Effective Orifice Area (EOAi) was assessed and did not influence observed long-term survival differences. Conclusions: This unusual lifetime study provided substantial evidence for the superiority of the pericardial over the porcine bioprosthesis in the aortic position in elderly patients. It demonstrated enhanced long-term survival benefits for elderly patients without any increase in perioperative mortality. It is intended to inform future investigation into aortic valve design.