19-mm biological aortic valve prostheses: long term gradients and related-Outcome

Introduction: Small-sized biological prostheses for aortic valve replacement (AVR) increase the propensity for residual left ventricular outflow stenosis resulting in an elevated trans-valvular gradient and subsequent compromised quality of life. The alternative is root enlargement or extended root procedures. We aimed to determine the long-term performance of implanted 19 mm supra annular pericardial prostheses.

Material and methods: 122 consecutive patients underwent AVR with 19-mm biological prosthesis (2008-2020). Serial postoperative echocardiographic data (pre operation, pre discharged, 1 year and most recent exams) and the respective clinical status were analyzed.

Results and discussion: Patient`s age ranged between 38 and 89 years (mean 72 ± 8.6), 83.6% were female gender. Average BSA was 1.72 ± 0.18 m2 (range, 1.25-2.3). Preoperative average velocity, peak and mean and trans-valvular gradients were 4.3m/s ±0.8m/s, 75.8 ± 18.7 mmHg and 47.3mmHg± 18.8 mmHg, respectively. Early postoperative average velocity, peak and mean trans-valvular gradients were 2.8m/s ±0.49m/s, 32.4 ± 12 mmHg and 18.6mmHg± 6.9 mmHg, respectively.

These indices remained stable during serial echocardiographic examinations (p=NS) at median post-operative follow-up duration of 33 months (range 1 to 139 months). We did not find significant long term gradient difference according to patient gender and BSA (59 patients had BSA<1.72 m2, 63 had BSA>1.72 m2 the mean gradients were 17.63 mmHg and 18.48 mmHg respectively (p=NS).

Conclusion: 19-mm biological valves significant reduce trans-valvular gradient, confer an acceptable hemodynamic performance in recipients assigned for biological prostheses. Recipients may probably achieve functional improvement and acceptable event-free survival.