Considerations for prostheses choice in multiple valve surgery

The prosthesis type for multiple valve surgery (replacement of two or more diseased native or prosthetic valves, replacement of two diseased valves with repair/reconstruction of a third, or replacement of a single diseased valve with repair/reconstruction of a second valve) remains inadequately evaluated. The clinical performance of multiple valve surgery with bioprostheses (BP) and mechanical prostheses (MP) was assessed to compare patient survival and composites of valve-related complications.

Between 1975 and 2000, 1245 patients had multiple valve surgery (BP 785, mean age 62.0 ± 14.7 years; and MP 460, mean age 56.9 ± 12.9 years). There were 1712 procedures performed [BP 969(56.6%) and MP 743(43.4%). Concomitant coronary artery bypass (conCABG) was BP 206(21.3%) and MP 105(14.1%) (p = 0.0002). The cumulative follow-up was BP 5131 years and MP 3364 years. Independent predictors were determined for mortality, valve-related complications and composites of complications.

Unadjusted patient survival at 12 years was BP 52.1 ± 2.1% and MP 54.8 ± 4.6% (p = 0.1127), while the age adjusted survival was BP 48.7 ± 2.3% and MP 54.4 ± 5.0%. The predictors of overall mortality were age [Hazard Ratio (HR) 1.051, p < 0.0001], previous valve (HR 1.366, p = 0.028) and conCABG (HR 1.27, p = 0.021). The actual freedom from valve-related mortality at 12 years was BP 85.6 ± 1.6% and MP 91.0 ± 1.6% (actuarial p = 0.0167). The predictors of valve-related mortality were valve type (BP > MP) (2.61, p = 0.001), age (HR 1.032, p = 0.0005) and previous valve (HR 12.61, p < 0.0001). The actual freedom from valve-related reoperation at 12 years was BP 60.8 ± 1.9% and MP85.6 ± 2.1% (actuarial p < 0.001). The predictors of valve-related reoperation were valve type (MP > BP) (HR 0.32, p < 0.0001), age (HR 0.99, p = 0.0001) and previous valve (HR 1.38, p = 0.008) CONCLUSIONS: Overall survival (age adjusted) is differentiated by valve type over 10 and 12 years and valve-related mortality and valve-related reoperation favours the use of mechanical prostheses, overall for multiple valve surgery.