Patient-prosthesis mismatch after small-size stentless aortic valve replacement

Area of Science:

• Cardiology
• Cardiac Surgery
• Biomedical Engineering

Background:

• Patient-prosthesis mismatch (P-PM) can occur after aortic valve replacement (AVR).
• The Cryolife O'Brien (CLOB) bioprosthesis is used in AVR procedures.
• Understanding P-PM implications is crucial for optimizing patient outcomes.

Purpose of the Study:

• To determine the incidence of P-PM after AVR using small-size CLOB bioprosthesis.
• To evaluate the clinical and hemodynamic consequences of P-PM in these patients.

Main Methods:

• Retrospective study of 62 patients undergoing AVR with 21-23 mm CLOB bioprosthesis.
• Effective orifice area (EOA) calculated and indexed to body surface area (BSA) for indexed EOA (EOAI).
• Mismatch defined as EOAI ≤ 0.85 cm²/m².

Main Results:

• Early P-PM (EOAI ≤ 0.85 cm²/m²) observed in 20% at discharge, decreasing to 3.3% at 6 months.
• Female sex, younger age, and smaller patient annulus index were predictors of mismatch.
• Mismatch was associated with higher mean gradients initially, but differences resolved by 1 year.
• No significant differences in midwall fractional shortening, survival, or clinical status were observed between groups.

Conclusions:

• P-PM after AVR with small CLOB bioprosthesis is an early postoperative phenomenon in a minority of patients.
• The mismatch resolved over time, with adequate indexed EOA to BSA in all patients at late follow-up.
• Early P-PM did not lead to adverse clinical repercussions or affect long-term outcomes.