ObjectiveTo analyze risk factors of early outcomes of mitral valvuloplasty (MVP)for the treatment of degenerative mitral regurgitation (DMR). MethodsClinical data of 132 DMR patients who underwent MVP in Fu Wai Hospital between January 1, 2011 and November 1, 2011 were retrospectively analyzed. A total of 114 patients (86.4%)were followed up after discharge with their mean age of 51.21±12.78 years, including 76 males (66.7%). Preoperative risk factors of early outcomes of MVP were analyzed. ResultsAmong those patients, there were 25 patients with atrial fibri-llation (AF)(21.9%). Preoperative ejection fraction was 63.88%±6.93%. Preoperative echocardiography showed left ventricular end-diastolic diameter (LVEDD)was 31.61±5.51 mm/m2. There were 66 patients (57.9%)with tricuspid regurg-itation, and 34 patients (29.8%)underwent concomitant tricuspid valvuloplasty including 10 patients (8.8%)who received tricuspid annuloplasty rings. Two patients died postoperatively, 2 patients underwent re-operation of mitral valve replacement or MVP respectively. Postoperative echocardiography showed moderate or severe mitral regurgitation in 15 patients. Preoperative risk factors of early outcomes of MVP included AF (36.8% vs. 18.9%, P=0.035), large LVEDD (34.02±3.76 mm/m2 vs. 31.15±5.68 mm/m2, P=0.042)and functional mitral regurgitation (15.8% vs. 1.1%, P=0.007). Multivariate analysis showed greater postoperative LVEDD reduction significantly lowered the incidence of postoperative events (HR 0.002, 95% CI < 0.001-0.570, P=0.031). ConclusionsEnlargement of the left ventricle is an independent preoperative risk factor for early outcomes of MVP for DMR patients. Greater postoperative LVEDD reduction significantly lowers the incidence of postoperative events.
Objective To study the effect of preparation conditions for small-diameter polyurethane(PU) vascular graft on microstructure and mechanical properties. Methods The small-diameter microporous PU artificial vascular grafts were prepared by dipping and leaching method. The dimension and microstructure were controlled by changing mold diameter, PU materials, salt sizes, salt to polymer ratio, times of dipping layers etc. The mechanical properties of PU grafts including radical compliance, water permeability, longitudinal strength, burst strength, and suture tearing strength were measured and the effect of the graft dimension and microstructure on their properties were studied. Results The internal diameter of grafts prepared was 2-4 mm depending on mold diameter. The wall thickness was 0.6-1.2 mmafter dipping 4-8 layers. The density was 0.23-0.49 g/cm3. The pore was 42-95 μm in diameter. The porosity was 56%80%. The radical compliance was 1.2%-7.4%·13.3 kPa-1 and higher compliances could be obtained by using moreelastic polyurethane, higher salt to polymer ratio, longer diameter and less wall thickness. The water permeability, mainly depending on salt to polymer ratio,diameter, and wall thickness, was 0.29-12.44 g／(cm2·min). The longitudinal strength was 1.55-4.36 MPa correlating with tensile strength of polyurethane and salt to polymer ratio. The burst strength was 60-300 kPa also depending on tensile strength of polyurethane and salt to polymer ratio. The suture tearing strength was 19.5-96.2 N／cm2 depending on tensile strength of polyurethanebut not on the angle of tearing and graft axial directions. The compliance and water permeability of Chronoflex grafts were higher than those of PCU1500 grafts, but longitudinal strength, burst strength, and suture tearing strength of PCU1500 grafts were better than those of Chronoflex grafts. Conclusion Small-diameter grafts with proper pore sizes, porosity, matching compliance can be obtained by selecting PU materials and optimizing the preparation conditions.
Objective To evaluate the effectiveness of multiple small-diameter drilling decompression combined with hip arthroscopy for early oeteonecrosis of the femoral head (ONFH). Methods Between March 2010 and December 2013, 91 patients with early ONFH were treated with the operation of multiple small-diameter drilling decompression combined with hip arthroscopy in 39 cases (53 hips, group A) or with drilling decompression alone in 52 cases (74 hips, group B). The patients in 2 groups had obvious hip pain and limited motion before operation. There was no significant difference in gender, age, etiology, effected side, stage of osteonecrosis, and preoperative Harris score between 2 groups (P>0.05). Results All operations succeeded and all incisions healed by first intention. The operation time was significantly longer in group A [(73.3±10.6) minutes] than in group B [(41.5±7.2) minutes] (t=8.726, P=0.000). Temporary of sciatic nerve apraxia after operation occurred in 2 patients of group A, and no complication occurred in other patients. Patients were followed up 24-52 months (mean, 39.3 months) in group A and 24-48 months (mean, 34.6 months) in group B. At last follow-up, the Harris scores were 83.34±8.76 in group A and 76.61±9.22 in group B, showing significant differences when compared between 2 groups (t=–4.247, P=0.029) and when compared with preoperative values in 2 groups (t=–10.327, P=0.001; t=–8.216, P=0.008). X-ray films showed that the collapse of the femoral head was observed in 6 hips (1 hip at stage Ⅰand 5 hips at stage Ⅱ) in group A, and in 16 hips (4 hips at stageⅠand 12 hips at stage Ⅱ) in group B; and hip arthroplasty was performed. The total effective rates were 88.68% (47/53) in group A and 78.38% (58/74) in group B, respectively; showing significant difference between 2 groups (χ2=5.241, P=0.041). Conclusion Multiple small-diameter drilling decompression combined with hip arthroscopy is effective in pain relief, improvement of hip function, slowing-down the process of femoral head necrosis, delaying the need for total hip arthroplasty in patients with early ONFH.
Retinal blood vessels are the only circulatory system that can be observed under non-invasive conditions. By observing the morphological changes of retinal blood vessels, the changes of blood circulation can be indirectly reflected. The occurrence, development and evolution of different diseases can be discovered. With the development of new detection technologies, especially the wide application of fundus photography and optical coherence tomography, a more intuitive and non-invasive quantitative index is provided for retinal vascular measurement. It is important for the diagnosis, guiding treatment and follow-up of related vascular diseases. This article reviews the development of retinal vessel diameter measurement methods and related applications in clinical diagnosis and treatment.
Reports about the application of transcatheter aortic valve replacement (TAVR) for patients with aortic stenosis, whose valve sizes exceed the maximum recommended annular diameter of the largest artificial valve, is rarely in China. This paper reports an aortic stenosis patient characterized by large aortic annulus diameter with severe calcification and treated by TAVR. A comprehensive and careful operation plan was made before the operation. The anterior and posterior balloon dilatation and coronary artery protection were used during the operation. The patient was followed up for 2 years and was in stable condition.
Objective To explore the strategy of intrathoracic anastomosis in patients with esophageal squamous cell carcinoma when the proximal esophagus is dilated to different degrees and explore its mechanism. Methods We retrospectively reviewed the clinical data of patients who underwent esophagectomy between 2014 and 2017 in West China Hospital. The patients were divided into two groups including a significant dilatation group with inner mucosal phase diameter (IMPD)≥17.9 mm and a non-significant dilatation group with IMPD<17.9 mm. And the patients were divided into two groups (a layered manual anastomosis group and a stapled anastomosis group) according to anastomosis method and propensity score matching was applied to adjust for potential confounders. Results We finally included 654 patients. There were 206 patients with 158 males and 48 females at average age of 62.21±7.72 years in the layerd manual analstomosis group and 448 patietns with 377 males and 71 females at average age of 62.57±8.42 years in the stapled anastomosis group. We also used Masson trichrome staining to assess the collagen fiber content in the esophagus. Compared with layered manual anastomosis, the incidence of anastomotic leakage was higher in the significant dilatation group than that in the stapled anastomosis group (original cohort: 3.8% vs. 10.7%, P=0.093; propensity score-matched cohort: 1.4% vs. 15.3%, P=0.004). And there was no significant difference in anastomotic leakage b etween layered manual anastomosis and stapled anastomosis in the non-significant dilatation group (original cohort: 4.7% vs. 4.2%, P=0.830; propensity score-matched cohort: 4.8% vs. 4.0%, P=0.206). Moreover, the average collagen fiber area ratio was significantly lower in the significant dilation group than that in the non-significant dilatation group (P=0.045). Conclusion There is a significant reduction in collagen fibers in the proximal esophageal wall tissue of esophageal squamous cell carcinoma patients with a IMPD≥17.9 mm. Intrathoracic layered manual anastomosis effectively reduces postoperative anastomotic leakage in these patients.
This study aims to explore the effect of aortic sinus diameter on aortic valve opening and closing performance in the case of no obvious disease of aortic valve and annulus and continuous dilation of aortic root. A total of 25 three-dimensional aortic root models with different aortic sinus and root diameters were constructed according to the size of clinical surgical guidance. The valve sinus diameter DS is set to 32, 36, 40, 44 and 48 mm, respectively, and the aortic root diameter DA is set to 26, 27, 28, 29 and 30 mm, respectively. Through the structural mechanics calculation with the finite element software, the maximum stress, valve orifice area, contact force and other parameters of the model are analyzed to evaluate the valve opening and closing performance under the dilated state. The study found that aortic valve stenosis occurs when the DS = 32 mm, DA = 26, 27 mm and DS = 36 mm, DA = 26 mm. Aortic regurgitation occurs when the DS = 32, 36 and 40 mm, DA = 30 mm and DS = 44, 48 mm, DA = 29, 30 mm. The other 15 models had normal valve movement. The results showed that the size of the aortic sinus affected the opening and closing performance of the aortic valve. The smaller sinus diameter adapted with the larger root diameter and the larger sinus diameter adapted with the smaller root diameter. When the sinus diameter is 40 mm, the mechanical performance of the valve are good and it can well adapt with the relatively large range of aortic root dilation.
Objective To analyze the quantitative relationship between respiratory effort and inferior vena cava (IVC) diameter variability in healthy adults, and explore the effects of respiratory effort on the fluid responsiveness with IVC diameter variability. Methods From October 2022 to May 2023, a cross-sectional study was conducted in healthy young subjects who met the criteria. Respiratory effort was evaluated by using portable pulmonary function to measure the subjects’ inspiratory conditions in three states (quiet breathing, moderate inspiration, and maximal inspiration). At the same time, the IVC internal diameter was measured by bedside ultrasound and the IVC diameter variability was calculated. The correlation between inspiratory volume and IVC diameter variation was analyzed, and the receiver operator characteristic (ROC) curve was drawn. The sensitivity and specificity of fluid responsiveness induced by inspiratory effort were predicted according to the area under the ROC curve (AUC). Results A total of 95 subjects were screened, aged 27.13±5.77 years, of whom 30 (32%) subjects were males. During quiet breathing, 41.1% of subjects had IVC inner diameter variation ≥50%. For moderate inspiration, it was 68.4%. At maximum inspiration, this proportion is more than 85%. Inspiratory volume was moderately positively correlated with IVC diameter variation, and the correlation coefficient r=0.45. With the IVC diameter variation ≥50% as the positive criterion for fluid responsiveness, the AUC of fluid responsiveness induced by inspiratory effort was 0.73 (95% confidence interval 0.67 - 0.78, P<0.001), and the inspiratory volume threshold was 13 mL/kg ideal body weight when the maximum Youden index was 0.41. That is, moderate force breathing can induce fluid responsiveness, with sensitivity of 79.57% and specificity of 61.62%. Conclusion The degree of respiratory effort significantly affects the IVC inner diameter variation, and there may be false positives in the evaluation of fluid responsiveness according to IVC inner diameter variation in the case of spontaneous breathing.
The aim of the present experimental study is to determine the effects of sinotubular junction diameter on artificial bioprosthesis valves. An experimental study was performed for aortic root models with different sinotubular junction taper under pulsatile flow condition. The sinotubular junction diameters were modified to create four models with different sinotubular junction tapers with 0, 1, 3 and 5 degrees, respectively, using three dimensional printing techniques. After installing the testing bioprosthesis valve on the aortic root models, we conducted experiments of the pulsatile flow testing with different stroke volume in the pulsatile circulation simulation system. The testing condition was set at the pulse frequency of 70 beats/min and the stroke volume of 2–7 L/min. The status of the valves in 10 continuous pulse cycles was tested and the average results were obtained for each stroke volume. The results of testing showed that the mean transvalvular pressure gradients agreed well with the national standard, and all smaller than 10 mm Hg. The sinotubular junction taper had an influence on regurgitation fraction of the artificial bioprosthesis valve. The smaller sinotubular junction taper showed beneficial effect to decrease the regurgitation fraction. In the case of smaller stroke volume, the smaller sinotubular junction taper was beneficial to increase the effective valve orifice area. In the case of larger stroke volume, the larger sinotubular junction taper was beneficial to increase the effective valve orifice area. This study indicates that a doctor should consider the smaller sinotubular junction taper in the case of smaller stroke volume more. In the case of larger stroke volume, the doctor should consider the larger sinotubular junction taper more.
Objective To explore the effectiveness and failure causes of large-head metal-on-metal total hip arthroplasty (large-head MoM THA). Methods Between March 2007 and May 2010, 159 patients (183 hips) underwent large-head MoM THA, and the clinical data were analyzed. There were 50 females (54 hips) and 109 males (129 hips) with an average age of 50 years (range, 20-78 years). Single hip was involved in 135 cases (left hip in 69 cases and right hip in 66 cases) and double hips in 24 cases. The causes included femoral head necrosis in 74 cases (93 hips), Legg-Calve-Perthes in 1 case (1 hip), osteoarthritis in 18 cases (19 hips), developmental dysplasia of the hip in 17 cases (18 hips), osteoarthritis after hip septic infection in 8 cases (8 hips), traumatic arthritis of the hip in 6 cases (6 hips), femoral neck fracture in 17 cases (17 hips), ankylosing spondylitis in 8 cases (11 hips), rheumatoid arthritis of hip in 9 cases (9 hips), and adult onset Still’s disease in 1 case (1 hip). Before operation, visual analogue scale (VAS) was 6.59±0.87; Harris score was 45.99±8.07. Results Healing of incisions by first intention was achieved, and no operative complication occurred. The patients were followed up 1.2-8.2 years (mean, 6.1 years). Implant failure was observed in 15 cases (17 hips), and the 5-year survival rate of large-head MoM THA was 91.80% (168/183). The causes of implant failure after THA were inflammatory pseudotumor in 4 cases (4 hips), acetabular aseptic loosening in 3 cases (3 hips), osteolysis in 4 cases (5 hips), acetabular aseptic loosening combined with inflammatory pseudotumor in 3 cases (3 hips), and functional disused in 1 case (2 hips). Of them, 9 cases (11 hips) did not receive revision surgery for various reasons, while 6 cases (6 hips) underwent revision surgery at 1.2-5.4 years (mean 3.7 years) after large-head MoM THA. At last follow-up, VAS and Harris score were 1.72±1.48 and 81.37±10.75 respectively, showing significant differences when compared with preoperative scores (t=–35.547，P=0.000；t=33.823，P=0.000). The function was excellent in 44 hips, good in 89 hips, fair in 33 hips, and poor in 17 hips. Conclusion Large-head MoM THA has a high revision rate during mid- and long-term follow-up because of inflammatory pseudotumor, acetabular aseptic loosening, and osteolysis. Early revision can effectively improve the function of the hip and improve patients’quality of life.