M. Kerem VURAL, Oğuz TAŞDEMİR, Şeref KÜÇÜKER, Erol ŞENER

Çıkan aort anevrizmalarının tamirinde stensiz domuz protezi ile aortik kök replasmanı

Amaç: Aortik kapak replasmanı gerektiren çıkan aort anevrizmalarının tedavisinde Freestyle® stentsiz domuz biyoprotezinin yeri, erken ve orta dönem sonuçları yönünden değerlendirilmiştir. Materyal ve Metod: Ardışık onsekiz hastaya (13 erkek / 5 kadın; ortalama yaş 52 ± 14) implantasyon yapıldı. Hastaların fonksiyonel kapasitelerinin yedisi NYHA class II, yedisi class III ve dördü de class IV idi. Ortalama çıkan aort çapı 61 ± 7 mm (50-80) olup tüm hastalarda önemli aort yetmezliği mevcuttu. Ortalama sol ventrikül sistol sonu çapı (LVSSÇ) 44 ± 14 mm, diyastol sonu çapı (LVDSÇ) 60 ± 14 mm, septal kalınlık (IVSK) 16 ± 2 mm ve ejeksiyon fraksiyonu (LVEF) %58 ± 8 idi. Bulgular: Mortalite %11 olup, mortalite prediktörleri olarak 90 dakikayı aşan aortik klempleme süresi (p = 0.04), %55'in altında ejeksiyon fraksiyonu (p = 0.03) ve biküspid aort kapak mevcudiyeti (p = 0.03) saptandı. Postoperatif takip süresi toplam 227 ay (ortalama 24 ± 3 ay) idi. Hastalar son kontrolleri itibariyle NYHA class I fonksiyonel kapasitede olup hiçbir hastada reoperasyon gerekmemiş olup kapağa bağlı komplikasyon gelişmedi. Ameliyattan bir yıl sonra ortalama maksimum sistolik aort gradiyenti 9 ± 4 mmHg olarak ölçülmüş, LVSSÇ 37 ± 6 mm'ye (p = 0.04), LVEDV 56 ± 4 mm'ye (p = 0.04) ve IVSK 10 ± 3 mm'ye (p = 0.02) geriledi. Ortalama ejeksiyon fraksiyonu ise %60 ± 12'ye (p = 0.05) yükseldi. Hastane mortalitesi dahil olmak üzere, 2 yıllık Kaplan-Meier yaşam oranı %88 ± 8 olarak bulundu. Sonuç: Bu sonuçlara göre stentsiz domuz aort kökü interpozisyonunun, aort kapak değişimini de gerektiren aort anevrizmalarında uygun bir cerrahi tedavi seçeneği olduğu düşünülmüştür. Özellikle yaşlı hastalarda, mikotik anevrizmalarda ve antikoagülan tedavinin istenmediği hallerde sağlayacağı avantajlar nedeniyle cerrahi envanterde tutulması gereken bir yaklaşımdır. Bununla birlikte, dayanıklılığının değerlendirilmesi için uzun vadeli çalışmalara ihtiyaç vardır.

Stentless porcine root replacement for ascending aortic aneurysm repair

Background: The clinical value of root replacement with Freestyle® stentless porcine bioprosthesis in the treatment of ascending aortic aneurysm with aortic valvular disease is assessed in regard to early and mid-term results. Methods: Eighteen consecutive patients (13 male / 5 female) underwent elective stentless porcine aortic root implantation. Mean age was 52 ± 14 years. Seven patients were in NYHA class II, another 7 in class III, and 4 in class IV. Average ascending aortic diameter was 61 ± 7 mm (range 50 to 80 mm) with severe aortic regurgitation in all cases. The average left ventricular end systolic diameter (LVESD) was 44 ± 1 4 mm, end diastolic diameter (LVEDD) was 60 ± 14 mm, septal thickness (IVST) was 16 ± 2 mm and ejection fraction (LVEF) was 58% ± 8%. Results: The operative mortality was 11%. An ejection fraction less than 55% (p = 0.03), an aortic clamping time exceeding 90 minutes (p = 0.04), and bicuspid aortic stenosis (p = 0.03) were the mortality predictors. Survivors were followed for an average period of 24 ± 3 months, a total of 227 months. All were in NYHA class I and free from reoperation or valve-related events as of their last follow-up. The average peak trans aortic systolic gradiyent was 9 ± 4 mmHg, LVESD regressed to 37 ± 6 mm (p = 0.04), LVEDD to 56 ± 4 mm (p = 0.04), and IVST to 10 ± 3 mm (p = 0.02); LVEF was increased to 60% ± 12% (p = 0.05) at the first postoperative year. Kaplan-Meier survival estimate was 88% ± 8% at 2 years, including operative mortality. Conclusions: These data establish that the stentless porcine aortic root replacement provides a reasonable surgical option for ascending aortic aneurysms necessitating aortic valve replacement. It may be the treatment of choice in the elderly, in mycotic aneurysms and where anticoagulation is not desirable, hence, should be included in the cardiovascular surgeon's armamentarium. However, their durability must be evaluated with long-term studies.

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