DISCUSSION

This is the first prospective evaluation of the Magna Ease bioprosthesis for surgical AVR. These results demonstrate good safety and effectiveness, with functional and hemodynamic outcomes that remain consistent over the 8‑year follow‑up.

Survival

Kaplan–Meier analyses showed freedom from all‑cause and valve‑related mortality at 8 years were 80.7% (95% CI 74.9, 86.4) and 95.8% (95% CI 92.8, 98.8), respectively. A recent retrospective study of AVR with the Magna Ease valve, with a median follow-up of 4.5 years, revealed overall survival at 12 years of 54% (95% CI 47.8, 62), albeit with limited numbers of patients. [13] Another retrospective, single-center study of the Magna Ease valve in 1,126 consecutive patients reported 78.2% survival probability at 9 years.[11] Studies of the Trifecta valve (Abbott Laboratories, IL, US) have shown comparable midterm all-cause and valve‑related mortality.[14-16] The Freestyle valve (Medtronic, Dublin, Ireland) showed similar rates of 10-year survival to Magna Ease in a retrospective cohort analysis.[17, 18] In another multivariable retrospective analysis, the Mitroflow valve (LivaNova, London, UK) was associated with a higher risk of mortality compared with the Magna Ease valve at 5 years (hazard ratio 1.57 [95% CI 1.17, 2.11], p<0.01).[19]

Thromboembolic events, bleeding, and endocarditis

Early and late complications in this study were consistent with others.[5, 14] Freedom from endocarditis, thromboembolism, and major bleeding at 8 years were 97.3% (95% CI 95.1, 99.5), 86.7% (95% CI 81.9, 91.5), and 85.1% (95% CI 80.0, 90.1), respectively. The reported rate of bleeding events does not pose an unexpected or additional risk to patients treated with the Magna Ease valve. Most of the bleeding events had no further clinical consequences, and those observed were typical for older patients following cardiac surgery.

Hemodynamic performance

Mean gradient remained acceptable at 8 years: 14.8±8.3 mmHg compared with 12.2±5.0 mmHg at 1 year, and was consistent with findings of a recent study.[11] Although one meta‑analysis concluded gradients were lower for the Trifecta valve than the Magna and Magna Ease valves at 6 months (mean difference 4.1 mmHg; 95% CI 3.5, 4.7; p<0.0001),[20] a recent large comparative analysis found a concerning decline in Trifecta hemodynamics over 5 years, with an increased rate of explant due to structural deterioration, compared with the original PERIMOUNT valve.[21]
The hemodynamic improvement seen in this study resulted in a sustained improvement in NYHA functional class for nearly two-thirds of patients.

Valve durability

Freedom from SVD was 99.1% (95% CI 97.9, 100.0) at 5 years and 90.1% (95% CI 84.7, 95.4) at 8 years. The 8-year rate is slightly lower than the 10-year freedom from SVD rates with the Magna Ease valve reported by Bourguignon et al. (94.2%) and Forcillo et al.(98±0.2%), or the 12-year rates from Piperata et al.(93%).[5, 13, 22] However, comparing SVD rates from different studies is challenging because of differing SVD definitions and cohort ages. Freedom from SVD with the Trifecta valve was reported to be 98.7% and 93.3% at 5 and 8 years, respectively,[15] although a recent study demonstrated increased risk of valve failure in the Trifecta valve compared with the Magna Ease valve at 48 months.[18]
Freedom from reintervention due to SVD was 99.1% (95% CI 97.9, 100.0) at 5 years and 93.6% (95% CI 89.3, 97.8) at 8 years. Rates reported for the Trifecta valve were 97.3% (95% CI 94.7, 98.6) at 6 years.[14, 23] In a propensity score-matched analysis between the Trifecta valve and the Magna Ease valve, the Trifecta valve cohort had a significantly higher risk of repeat AVR for structural valve failure at 7 years (5.7% vs 0%, p=0.009).[16] Another propensity score-matched analysis showed a significantly lower freedom from explant for the Trifecta valve compared with the PERIMOUNT valve at 5 years (95.9% vs 98.7%, p<0.001).[21]
In an effort to reduce SVD and improve durability of bioprosthetic valves, Edwards Lifesciences has developed RESILIA tissue with advanced anticalcification technology, but durability data beyond 5 years with this tissue are still awaited.[24, 25]

LIMITATIONS

This study has some limitations. While it includes outcomes from 14 centers and used an independent CEC to adjudicate safety events, an echo core lab was not used, potentially introducing variability, as echocardiographic data were collected and evaluated by individual centers. Secondly, this study did not include a comparator study arm to compare these Magna Ease valve outcomes to those of other contemporary valves.

CONCLUSION

This is the first multicenter, prospective cohort study of the Magna Ease valve, with clinical events committee adjudication of all safety events. The Magna Ease valve demonstrated satisfactory freedom from mortality and valve-related complications requiring reintervention, and sustained improvement in hemodynamics at 8 years. These data support the continued use of this valve, adding to the growing body of evidence that the Magna Ease valve represents a standard of performance against which other surgical valves may be compared.[7, 11]