1.Apicoaortic Conduit Bypass Surgery for Severe Calcific Aortic Valve Stenosis
Akitatsu Yamashita ; Akihiko Sasaki
Japanese Journal of Cardiovascular Surgery 2011;40(5):247-250
We report a case of a 79-year-old woman who underwent apicoaortic conduit bypass (ACB) surgery for severe calcific aortic valve stenosis. We did not perform conventional aortic valve replacement because of the patient's advanced age and because she had a small aortic annulus (17 mm) and a high risk of bleeding and cerebral infarction. ACB surgery through a left thoracotomy was performed via a femorofemoral bypass. A hand-made valve conduit was made from the left ventricular apex to the descending aorta. Her postoperative course was uneventful ; postoperative echocardiography showed a decreased pressure gradient at the native aortic valve between the left ventricle and the aorta. This procedure is useful in high-risk patients with severe calcified aortic valve stenosis.
2.Long-Term Outcome of Ultrasonic Scalpel Coronary Artery Bypass Grafting Using Bilateral Internal Thoracic Arteries
Akitatsu Yamashita ; Satomi Inoue ; Toshiyuki Maeda ; Masaki Tabuchi
Japanese Journal of Cardiovascular Surgery 2015;44(6):307-311
It seems obvious that artery grafts improve the long-term prognosis of coronary artery bypass grafting (CABG). Besides, the superiority of using bilateral ITAs compared with a single ITA has been reported. An ultrasonic scalpel was introduced in our hospital in April 2001, and since then, we have harvested bilateral ITAs with it in a full skeletonized fashion, and as a result, we have been using bilateral ITAs for CABG routinely. In this study, we reviewed the surgical outcomes in 256 patients who underwent CABG alone, using bilateral ITAs harvested with ultrasonic scalpel between April, 2001 and December, 2012. Of these patients, 194 underwent off-pump CABG (8 were converted to on-pump CABG), and 38 required emergency surgery. One patient died from cerebral infarction within 30 days after the operation. Of all 256 patients, 234 underwent graftograms within 2 weeks after surgery, and 10 patients (4.3%) needed re-intervention including redo CABG or PCI in the early stage. None of these suffered mediastinitis. We also studied long-term outcomes. The follow-up rate was 100% and the mean follow-up period was 2.97±2.6 years. The survival rate was 81.8%, and 72.6% at 5 years, and 10 years, respectively. The freedom from redo CABG was 99.5%, and 99.3% at 5 years, and 10 years, respectively. The freedom from PCI was 96.3%, and 95.2% at 5 years, and 10 years, respectively. The freedom from MACE was 90.3%, and 81.2% at 5 years, and 10 years, respectively. Bilateral ITAs harvested with an ultrasonic scalpel can be used for CABG safely and with satisfactory long-term results.
3.Evaluation of Decellularized Arteries Derived from Biological Tissue
Akitatsu YAMASHITA ; Seiichi FUNAMOTO ; Younguei ZHANG ; Yoshihide HASHIMOTO ; Akio KISHIDA
Japanese Journal of Cardiovascular Surgery 2020;49(2):45-51
Background : Cardiovascular surgery involves the use of several artificial materials as graft vessels. Although artificial blood vessels of medium and large diameters currently present a satisfactory patency and durability, those of small diameter remain inferior to one's own vessels to prevent issues such as early thrombosis and vascular stenosis. The present study aimed to investigate the functionality of decellularized tissues that hold structures and growth factors derived from a living body. Methods : Mini pigs were used for the study. The bovine-derived decellularized blood vessels were transplanted into the pigs' carotid artery, and no anticoagulant or antiplatelet drugs were used after the surgery. The blood vessels were dissected and evaluated for patency and tissue staining. Result : The patency of the blood vessels was confirmed in all cases ; however, a thrombus was confirmed in one transplanted vessel. Pathological findings showed maintenance of the blood vessel structure, presenting no issues with collagen or elastin. Conclusion : This study demonstrated that biologically derived decellularized blood vessels are highly functional and present an intact luminal basement membrane, even without antiplatelet therapy. This study suggested that decellularized blood vessels can potentially help in the development of medical devices with higher functionality than that of the existing materials.