The Spanish Monostrut Study Group: a ten-year experience with 8,599 implants

Area of Science:

• Cardiovascular Surgery
• Biomaterials Science
• Medical Device Engineering

Background:

• The Monostrut valve is a weld-free, pyrolytic carbon, tilting-disc prosthesis.
• Established in Spain in May 1983, the Spanish Monostrut Study Group initiated a prospective evaluation of this device.

Purpose of the Study:

• To prospectively evaluate the long-term performance and safety of the Monostrut valve.
• To assess valve-related complications and patient outcomes over a 10-year period.

Main Methods:

• A total of 8,599 Monostrut valves were implanted in 7,317 patients across 22 centers over 10 years.
• Follow-up data was 96% complete, with a mean follow-up of 4.3 years, totaling 29,155 patient-years.
• Procedures included aortic (3,229), mitral (2,806), and double valve replacements (1,282).

Main Results:

• The 10-year probability of freedom from structural deterioration was 100%.
• Key complication rates included nonstructural dysfunction (96% +/- 0.5%), thromboembolism (82.9% +/- 1.5%), and anticoagulant-related hemorrhage (87.6% +/- 1.4%).
• Actuarial freedom from reoperation was 95% +/- 0.5%, with 94% of patients in New York Heart Association class I-II post-implantation.

Conclusions:

• The Monostrut valve exhibits exceptional durability with no observed structural failures in a decade.
• The study confirms a low incidence of valve-related complications, supporting its safety and efficacy.
• Long-term data indicates favorable patient outcomes and a low reoperation rate.