Sabahattin GÖKSEL, Mehmet Ali ÖZATİK, Zafer İŞCAN, Oğuz TAŞDEMİR, Ülkü YILDIZ, Kamil GÖL, Binali MAVİTAŞ

"Medtronic freestyle stentsiz biyoprotez" lerle yapılan aort kapak replasmanlarının erken ve orta dönem sonuçları

Amaç: İleri yaş grubunda, stensiz ve kalsifikasyon önleyici alfa-amino-oleik asit ile muamele edilmiş bir biyoprotez olan "Medtronic Freestyle" ile yapılan aort valv replasmanlarının (AVR) erken ve orta dönem sonuçlarının değerlendirilmesi. Materyal ve Metot: 13'ü kadın (%35), ortalama yaşları 61.6 $pm$ 6.5 (55-71) olan toplam 40 hastada Medtronic Freestyle stentsiz biyoprotez kullanılarak AVR yapıldı. Preoperatif NYHA'ya göre ortalama fonksiyonel kapasiteleri 2.9 idi. 5 olguda diabet ve 3 olguda hipertansiyon hikayesi mevcuttu. Aort darlığı nedeni ile ameliyat edilen olgularda ortalama preoperatif aortik sistolik gradient 78 $pm$ 29 mmHg idi. Ortalama kros-klemp süresi 79 $pm$ 12 dakika, ortalama kardiyopulmoner bypass süresi 110 $pm$ 27 dakika olarak bulundu. Bulgular: Erken postoperatif dönemde 1 hasta kaybedildi (% 2.5). Taburcu edilen hastalar toplam 60.1 yıl takip edildiler. Ortalama takip süresi 18.9 $pm$ 12.3 aydı. Takipte 2 olgu non-kardiyak nedenlerle kaybedildi. 1 yıllık gerçekleşen yaşam beklentisi %94.9, 18 ay için %92.2 olarak bulundu. Sol ventrikül kas kitle indeksi anlamlı derecede azalma gösterdi (p = 0.02). Takip boyunca hastalarda tromboemboli, prostetik kapak endokarditi yada paravalvüler leak görülmedi, hemoliz tespit edilmedi. Yapısal kapak bozulması veya reoperasyon gereksinimi olmadı. Sonuç: Stentsiz biyoprotez kapaklar üstün hemodinamik performansları, sol ventrikül hipertrofisinin gerilemesi üzerinde olumlu etkileri ve orta dönem takipte kapağa bağlı komplikasyon oranlarının çok düşük olması nedeni ile, uzun dönem durabiliteleri ile ilgili yeterli klinik çalışmalar henüz bulunmamasına karşın, ileri yaşlardaki hastalarda iyi bir seçenektir.

Early and mid-term results of aortic valve replacement with medtronic freestyle stentless bioprosthesis

Background: To evaluate the early and mid-term results of aortic valve replacements (AVR) in an older patient group with a stentless valve "Medtronic Freestyle" which is pretreated with an anti-mineralizing agent, alpha-amino-oleic acid. Methods: AVR was performed with Medtronic Freestyle bioprosthesis to 40 patients with a mean age of 61.6 $pm$ 6.5 years (55-71).Thirteen (35%) of the patients were female. Mean preoperative functional capacity according to NYHA was 2.9. Five patients had diabetes and 3 patients were hypertensive. Mean preoperative systolic aortic gradient was 78 $pm$ 29 mmHg in cases that were operated for aortic stenosis. Mean cross-clamp duration and cardiopulmonary bypass time were 79 $pm$ 12 minutes, and 110 $pm$ 27 minutes respectively. Results: One patient died in the early postoperative period (2.5%). Total follow-up of the patients those were discharged were 60.1 years. Mean follow-up was 18.9 $pm$ 12.3 months. Two late deaths occurred during the follow up due to non-cardiac causes. Actuarial survival rate for 12 months was calculated to be 94.9% and 92.2% for 18 months. Left ventricular mass index decreased significantly (p =0.02). During the follow-up, no valve related complications such as thromboemboli, prosthetic valve endocarditis or paravalvular leak were observed. Structural valve dysfunction was not seen and no reoperations were needed. Conclusion: Even though long term durabilities need to be proven, stentless bioprosthesis with their superior hemodynamic performance, advantages for the regression of left ventricular hypertrophy and with minimal valve related complications in the mid term follow-up, are better choices compared to other valves in the elderly.

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