ObjectiveTo summarize the indication and surgical experiences of valve replacement, high-risk factors and long-term results for aortic regurgitation and large left ventricle. MethodsWe retrospectively analyzed the clinical data of 42 patients with aortic regurgitation and left ventricle end-diastolic diameter (LVEDD) ≥70 mm and left ventricle end-systolic diameter (LVESD) ≥ 50 mm in our hospital from March 2004 through December 2012. There were 38 males and 4 females,aged 16-73 (45.86±14.99) years. The patients underwent aortic valve replacement, who were evaluated by echocardiography at pre-operation, pre-discharge and early follow-up. The follow up period was 12-132 months. ResultsEarly death occurred in one patient. And five patients died during the follow-up. One week after surgery in 41 patients, LVEDD (62.00±13.21 mm), LVESD (50.71±14.02 mm), indexed LVEDD (35.23±8.58 mm/m2), indexed LVESD (28.92±9.08 mm/m2), LVEF (46.41%±12.49%), were significantly smaller than those before the operation (P<0.01). Heart function grades, preoperative EF, LVEDD and indexed LVEDD were the predictors for left ventricular function recovery. One-year, 5-year, 10-year survival rate was 92.9%, 90.2%, 83.8%, respectively. ConclusionMost of patients with aortic regurgitation and large left ventricle still have indications for surgical treatment, but severe left ventricular dysfunction and ventricular arrhythmia are high risk factors for long-term survival.
The heart valve prosthesis must have excellent hydrodynamic performance which is usually tested in vitro, not in vivo. This paper comprehensively introduced the principles and methods of hydrodynamic performance in vitro testing, helping clinicians to understand valve performance parameters, evaluate valve applicability, and reduce clinical risk of the valve prosthesis. In vitro testing not only serves as the "gold standard" for valve prosthesis assessment, but also provides detailed data for design and optimization of the prosthesis. ISO 5840 defines the items and methods for valve in vitro testing, which consists of three parts: (1) pulsatile flow testing, which reproduces the pulsating flow of the valve prosthesis after implantation in the human body; (2) steady flow testing, which assesses valve forward flow resistance; (3) durability testing, which evaluates the durability of the valve prosthesis and determines the expected failure mode. In addition, the paper presented the differences between atrioventricular and aortic valve testing, the method of mitral valve testing, the differences between transcatheter and surgical valve testing, and the method of valve flow visualization.