Quattro valve trial at mid-term: December 1996 to November 2004.

BACKGROUND AND AIM OF THE STUDY

The Quattro valve is a stentless pericardial mitral bioprosthesis that is treated with a post-tanning aldehyde capping designed to reduce calcification. A prospective trial was started in December 1996; herein are reported the results of the three centers that performed the surgery and followed up patients in the majority of cases. Young patients were deliberately included in the trial.

METHODS

Follow up data from 175 patients (mean age 46 years; range: 12-87 years) were collected and analyzed. Among patients, 44% were aged < 40 years. Follow up was 91% complete; mean follow up was 3.4 years (range: 0-7.5 years); total follow up was 465 patient-years (pt-yr). Clinical outcome was assessed according to the AATS/STS guidelines, and results analyzed according to Kaplan-Meier product limit calculation and by FDA Optimal Performance Criteria (OPC).

RESULTS

Early mortality was 1.7% (all non-valve related). At 60 months after surgery, mean overall survival was 84.8 +/- 3.6%, mean overall freedom from valve-related death was 99.2 +/- 0.9%, and mean overall freedom from calcification, pannus and tears was 96.1 +/- 2.2%. FDA OPC values (data for mechanical valve, tissue valve, Quattro valve in patients aged < 40 years and of all ages, respectively; expressed as %/pt-yr) were as follows: thromboembolism/stroke 3.0, 2.5, 0, 0.4; thrombosis 0.8, 0.2, 0, 0; major hemorrhage 1.5, 0.9, 0, 0.4; major perivalvular leak 0.6, 0.6, 0.4, 0.6; late endocarditis 1.2, 1.2, 1.8, 1.3; calcification/pannus 0, 0, 0.8, 0.6. Statistical analysis of these data showed there to be no difference between patients aged less or more than 40 years.

CONCLUSION

Overall mid-term results with the Quattro valve were acceptable. The lack of early calcification in young patients shows promise. More young patient-years of follow up will be needed to establish a secure indication for use in young, rheumatic patients where anticoagulation control is deficient.