Objective To study the development of a physiologic fixation method and investigate the effect of physiologic fixation method on porcine aortic root and aortic valve leaflets. Methods Physiological fixer of aortic root was manufactured in a factory. The fixers with different diameter were made of organic glass. Porcine aortic root with ascending aorta and anterior leaflet of mitral valve and partial ventricular septum were dissected out from the fresh heart. The roots were attached to appropriately sized inflow and outflow spigots. Physiologic fixation was utilized to maintain aortic root and leaflets natural anatomical shape, the aortic root was pressurized to the inflow and outflow portions simultaneously, and the leaflets floated freely at zero-pressure differential with in the pressurized root. Results The process of physiologic fixation retained the properties of a native valve. The leaflets were much softer and extensible than those from valves fixed under low pressure. The results of pulsatile flow testing indicated that the effective orifice areas of predilation at 80mmHg were significantly greater than those of predilation at 40 mmHg（P〈0.05）, while mean pressure differences were found to be lower comparatively（P〈0.05）. This difference translates into a mode of valve function that more closely approximates that of the native aortic valve. Conclusion Physiologic fixation process retains the valve＇s natural anatomical shape as well as the underlying structure of the leaflets, providing improved flow characteristics.
Abstract： Objective To investigate the longterm complications and preventions of rapid twostage arterial switch operation through longterm follow-up. Methods We reviewed the clinical information of 21 patients of rapid twostage arterial switch operation from September 2002 to September 2007 in Shanghai Children’s Medical Center. Among them, there were 13 males and 8 females with an average age of 75 d (29-250 d) and an average weight of 5 kg (3.5-7.0 kg). The data of left ventricle training period and the data before and after the twostage arterial switch operation were analyzed, and the risk factors influencing the aortic valve regurgitation were analyzed by the logistic multivariable regression analysis. Results The late diameter of anastomosis of pulmonary and aortic artery were increased compared with those shortly after operation (0.96±0.30 cm vs. 0.81±0.28 cm, t=-1.183,P=0.262; 1.06±0.25 cm vs. 0.09±0.21 cm, t=-1.833,P=0.094), but there was no significant difference. The late velocity of blood flow across the anastomoses was not accelerated, which indicated no obstruction. The late heart function was better than that shortly after operation, while there was no significant difference between left ventricular ejection fraction(LVEF) during these two periods (62.88%±7.28% vs. 67.92%±7.83%,t=1.362,P=0.202). The late left ventricular end diastolic dimension(LVDd) was significantly different from that shortly after operation (2.16±0.30 cm vs.2.92±0.60 cm，t=-5.281，P=0.003). Compared with earlier period after operation, the thickness of left ventricular posterior wall thickness（LVPWT）was also increased (0.39±0.12 cm vs. 0.36±0.10 cm,t=0.700,P=0.500), but there was no significant difference. The postoperative aortic valve regurgitation was worsened in 4 patients (30.77%, 4/13), not changed in 7 patients and alleviated in 2 patients compared with that before operation. There was no severe regurgitations during the followup. The logistic regression analysis showed that the small preoperative diameter ratio of aortic valve to pulmonary valve and long follow-up time were two risk factors for the [CM(159mm]aggravation of aortic regurgitation. Conclusion There is a relatively high aortic regurgitation rate after rapid two stage arterial switch operation, but there is no later death or reoperation and the survival conditions are satisfactory. All patients must be followed up periodically to check the anastomosis of pulmonary and aortic arteries and the aortic valve.
ObjectiveTo summarize the clinical experience in the treatment of high-risk patients with severe aortic valve disease by transcatheter aortic valve implantation (TAVI) via heart apex approach and to evaluate the early efficacy.MethodFive patients who underwent TAVI via heart apex approach from September 2017 to February 2019 in Henan Thoracic Hospital were retrospectively analyzed, including 3 males and 2 females, aged 65-84 (74.6±4.5) years.ResultAll operations were performed through a small left incision into the thoracic cavity (3-5 cm), and then through the J-Valve transport system, the aortic valve was successfully released via heart apex after precise positioning under digital subtraction angiography. One patient developed ventricular fibrillation during the operation, and the operation was completed with the assistance of emergency femoral arteriovenous catheterization cardiopulmonary bypass; one patient underwent percutaneous coronary intervention first because of severe coronary stenosis; one patient had paroxysmal atrial fibrillation during the perioperative period, and had hepatorenal insufficiency and thrombocytopenia after the operation, and was improved after medical treatment; one patient had perivalvular leak during the operation, and was improved after re-implantation of the valve; one patient was in stable condition during operation and recovered smoothly after operation. Surgery was successful in all 5 patients. The follow-up time was 2-19 months, and the early clinical effect was good.ConclusionThe short-term clinical efficacy of TAVI via heart apex approach in the treatment of high-risk severe aortic valve disease is definite and safe, but the long-term and medium-term effects need to be further evaluated.
ObjectiveTo analyze the early- and middle-term prognosis of various surgical methods in children with congenital aortic valve diseases, to provide reference for surgical methods in children with aortic valve stenosis or regurgitation.MethodsThe clinical data of 85 children with various aortic valve diseases treated in the Children’s Hospital of Fudan University from January 2005 to December 2018 were retrospectively analyzed. There were 64 males and 21 females, with an average age of 45 months ranging from 5 days to 15 years. Among them 18 patients underwent balloon aortic valvuloplasty (BAV), 8 surgical aortic valvotomy (SAV), 27 aortic valve autogenous pericardium repair, 16 mechanical arterial valve replacement and 16 Ross operation. They were followed up for 6.25±2.76 years. The re-intervention and survival status after different operations were analyzed.ResultsThere were 3 deaths and 17 reoperations in 85 children. The 5-year survival rate of the patients with SAV, BAV, aortic valve autogenous pericardium repair, mechanical arterial valve replacement and Ross operation was 87.4%, 88.9%, 100.0%, 100.0% and 100.0%, respectively; there was no statistical difference in the early and middle-term survival rates among various operations (P>0.05). The 5-year free from re-intervention rate of the patients with SAV, BAV, aortic valve autogenous pericardium repair, mechanical arterial valve replacement and Ross operation was 44.4%, 18.4%, 100.0%, 66.9% and 80.5%, respectively; there was a statistical difference in the early and middle-term re-intervention rate among various operations (P<0.05).ConclusionThe operation of congenital aortic stenosis or regurgitation needs to be performed according to the pathological changes of the valvular tissues. For children with severe lesions, SAV is recommended for the first intervention. For congenital aortic stenosis, SAV and BAV are both palliative operations which need further evaluation and re-intervention. Ross operation and mechanical arterial valve replacement have low re-intervention rate, and the middle- and long-term follow-up shows that the effect is accurate. Aortic valve autogenous pericardium repair is expected to become a method to delay or replace Ross operation and valve replacement.
Heart valve replacement is the major surgical treatment of severe valvular diseases. Due to the durability and reoperation-free, mechanical valves are widely used. Bioprosthesis valves became popular recently because of long service life and no demand for lifelong anticoagulation. However, how to choose the appropriate prosthetic heart valves, especially the application of bioprosthesis valves for patients at 55 to 65 years is still a major problem. This review focuses on more effective and scientific basis for rational choice of mechanical and bioprosthesis valve.
ObjectiveBy comparing the difference between different stenosed degree of aortic valve in flow field uniformity and turbulent shear stress (TSS), to explore the relation between flow field uniformity and different stenosed degree of aortic valve, and probe the clinical value for deciding the operation timing, and analyze the possible role of TSS in the progress of the disease.MethodsThe flow field uniformity values and TSS in parasternal long axis plane and apical five cavity plane on each point were measured and calculated by pulse wave Doppler echocardiography technique for 33 patients with different stenosed degree of aortic valve.ResultsThere were significant difference between the different stenosed degree of aortic valve in maximal velocity difference(ΔV max )and TSS( P lt;0.05, 0.01). The more severe the aortic stenosis was, the worse the flow field uniformity was, the lower the TSS was.ConclusionsThere are significant difference between the patients of different stenosed degree of aortic valve in flow field uniformity. Flow field uniformity has important value in classifying the degree of aortic stenosis and deciding the timing of operation. The more severe the aortic stenosis is ,the lower TSS is. It can be thought that low TSS distribution has important role in pathological process of constriction in cardiovascular system diseases.
ObjectiveTo evaluate early and midterm outcomes of aortic root enlargement (ARE) combined with supra-annular valve implantation for adult patients with aortic stenosis (AS) and small aortic roots (SARs). MethodsFrom January 2007 to July 2011, ARE combined with supra-annular valve implantation was performed for 38 adult patients with AS and SARs in Department of Cardiac Surgery of Beijing Anzhen Hospital. There were 12 males and 26 females with their age of 16-58 (38.6±21.0) years, body weight of 48-78 (58.5±12.0) kg, body height of 153-176 (162.8±12.0) cm and a mean body surface area (BSA) of 1.67±0.32 m2. There were 19 patients with rheumatic AS, 11 patients with congenital bicuspid aortic valve and AS, 5 patients with degenerative AS and 3 patients with AS and infective endocarditis. Preopera-tively, 8 patients were in NYHA class Ⅱ, 29 patients were in NYHA class Ⅲ, and 1 patient was in NYHA class Ⅳ. Aortic annular diameter (AAD) was 15-20 (17.6±2.8) mm and trans-aortic pressure gradient was 53-75 (62.8±10.5) mm Hg. ResultsCardiopulmonary bypass time was 83-145 (112±29) minutes, and aortic cross-clamping time was 58-116 (87±28) minutes. Intraoperative measurement of AAD was 15-20 (17.3±2.6) mm, AAD after ARE was 20-25 (22.6±2.3) mm. AAD after ARE was 12-17 (14.0±2.6) mm larger than AAD before ARE. Actual size of prosthetic valves was 2-3 sizes larger than predicted size without ARE in all the patients. There was no perioperative death or severe complication including bleeding. Length of ICU stay was 12-41 (26±14) hours, and length of hospital stay was 9-15 (12.5±3.2) days. A total of 37 patients (97.4%) were followed up for over 2 years after discharge. All the patients were in NYHA class Ⅰ. Grade 2/6 systolic murmur was heard in 3 patients. Electrocardiogram (ECG) showed significant improvement or complete disappearance of left ventricular hypertrophy in 35 patients, and mild left ventricular hypertrophy in 2 patients. ECG during follow-up didn't show any sign of myocardial ischemia, ventricular arrhythmia or severe atrioventricular block in any patient. ConclusionEarly and midterm outcomes of ARE combined with supra-annular valve implantation for adult patients with AS and SARs are satisfactory, but long-term outcomes of this procedure need further follow-up.
Objective To assess clinical outcomes of valve-sparing aortic root replacement for patients with aortic root aneurysm.?Methods?From February 2001 to September 2010， sixty patients with aortic root aneurysm underwent valve-sparing aortic root replacement in Fu Wai Hospital. There were 44 male patients and 16 female patients with an average age of 37.2±13.0 years （ranging from 9-64 years）. Fifteen patients had aortic dissection， 10 patients had ascendingaorta aneurysm， 25 patients had Marfan syndrome， and 2 patients had bicuspid aortic valve. Aortic root reconstruction was performed in 53 patients and aortic valve reimplantation was performed in 7 patients. Preoperative and postoperative heart function and degree of aortic insufficiency （AI） were compared.?Results?Valve-sparing aortic root replacement was performed in all patients. There was no in-hospital death or severe postoperative complications in this group. The median duration of mechanical ventilation was 13 hours （ranging from 2 to 1 110 hours） ， while the mean intensive care unit stay was 2.7±2.5 days （ranging from 1 to 18 days） . Postoperative echocardiography showed AI degree was significantly reduced in all the patients. Only three patients had moderate to severe AI， and all the other patients had none or trivial AI. All the patients were followed up for 2-122 （61.5±35.9） months. During follow-up， 4 patients were lost， 9 patients died， and the overall survival rate was 83.9% （47/56）. Two patients underwent aortic valve replacement in the 13 th and 14 th postoperative month respectively because of severe AI. Heart function of 47 patients was significantly improved compared with their preoperative heart function. Thirty-five patients （74.4%）were in New York Heart Association （NYHA） functional classⅠ， and 8 patients （17.0%） were in class II. Forty patients （85.1%）were free from moderate or severe AI.?Conclusion Valve-sparing aortic root replacement has satisfactory long-term outcomes for patients with aortic root aneurysm， and valve-related complication rate is low.
Abstract： Objective To investigate the effects of βreceptor blocker on intraventricular pressure gradient and left ventricle remodeling after valve replacement for critical aortic stenosis. Methods Fifty-six patients with critical aortic stenosis underwent aortic valve replacement surgery from January 2008 to January 2010 in the First Affiliated Hospital of Zhengzhou University. Thirtytwo of them who were followed up were selected to be enrolled in this study. The patients were divided into two groups under the same basis of clinical features. Twelve patients in the experimental group received oral βreceptor blocker (Metoprolol, 6.2525.00 mg once, twice daily). The rest 20 patients in the control group had no βreceptor blocker. The various indicators of ultrasound cardiogram (UCG) shortly after operation (within a week) and long after operation (6-24 months) were compared between the two groups. Results No death occurred in both groups, and chest distress, shortness of breath and other symptoms were obviously alleviated. Although left ventricular endsystolic dimension (LVESD) and left ventricular outflow tract dimension (LVOTD) of both groups increased 6-24 months after operation, compared with the early postoperative period, only the increase of LVOTD in the experimental group showed statistical difference (t=-47.937, P=0.001). In both groups, interventricular septum thickness (IVST), left ventricular posterior wall thickness (LVPWT), filament band velocity of left ventricular outflow tract (V), intraventricular pressure gradient (G) and left ventricular mass index (LVMI) of the later period after operation were significantly lower than those of the early postoperative period. All these indicators in the experimental group showed significant differences (t=7.781, P=0.001；t=5.749, P=0.001; t=2.637, P=0.023; t=7.167, P=0.001; t=100.061, P0.001), while only V, G， and LVMI showed statistical differences in the control group (t=4.051, P=0.001; t= 4.759, P= 0.001; t=-0.166,P=0.001). EF in the experimental group also indicated significant difference compared with early period after aortic valve replacement (t=-6.621, P=0.001). EF between two groups indicated no significant difference (t=-0.354,P=0.726). But differences between the two groups in LVEDD, IVS, G， and LVMI were all statistically significant in the later period after surgery (t=-2.494, P=0.018; t=-3.434, P=0.002;t=-2.171,P=0.038; t=-2.316, P=0.028). Conclusion β-receptor blocker is a safe and reliable drug for those patients who have undergone aortic valve replacement surgery for critical aortic stenosis, and can decrease significantly the residual intraventricular pressure gradient and accelerate left ventricular cardiac remodeling.
Objective To investigate the feasibility of a long-term left ventricular assist device placed in the aortic valve annulus for terminal cardiopathy. Methods An implantable aortic valve pump （23ram outer diameter, weighing 31g） was developed. There were a central rotor and a stator in the device. The rotor was consisted of driven magnets and an impeller, the stator was consisted of a motor coil with an iron core and outflow guide vanes. The device was implanted identical to an aortic valve replacement, occupying no additional anatomic space. The blood was delivered directly from left ventricle to the aortic root by aortic valve pump like natural ventricle, neither connecting conduits nor ＂bypass＂ circuits were necessary, therefore physiologic disturbances of natural circulation was less. Results Aortic valve pump was designed to cycle between a peak flow and zero net flow to approximate systole and diastole. Bench testing indicated that a blood flow of 7L/min with 50 mmHg（1kPa = 7.5mmHg） pressure could be produced by aortic valve pump at 15 000r/min. A diastole aortic pressure of 80mmHg could be maintained by aortic valve pump at 0L/min and the same rotating speed. Conclusions This paper exhibits the possibility that an aortic valve pump with sufficient hemodynamic capacity could be made in 23mm outer diameter, 31g and it could be implantable. This achievement is a great progress to extend the applications of aortic valve pump in clinic and finally in replacing the natural donor heart for heart transplantation. Meanwhile, this is only a little step, because many important problems, such as blood compatibility and durability, require further investigation.