Transcatheter aortic valve replacement (TAVR) has become a common theraputic option for aortic stenosis, but the evidence for precise anatomy for TAVR is accumulating. This paper presents the case of an 71-year-old female patient who had an extremely high risk of coronary obstruction due to both coronary ostia lying too low. The patient underwent TAVR with the help of coronary protection successfully. During the procedure, the patient was protected with wires only for both coronaries. After deployment, angiofluoroscopy suggested that chimney stenting should be applied for left coronary. The whole procedure was unenventful and both coronaries were seen.
Objective To investigate the role and mechanism of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) in the activation of aortic valve interstitial cells (AVICs) in aortic stenosis. Methods Isolating primary AVICs and stimulating their activation with transforming growth factor β1 (TGF-β1, 30 ng/mL), the expression of PGC-1α was detected. The activation of AVICs induced by TGF-β1 was observed after overexpression of PGC-1α by adenovirus or inhibition of PGC-1α function by GW9662. The possible downstream molecular mechanism of PGC-1α in AVICs activation was screened. Finally, the phenotype was further verified in primary human AVICs. Results The expression of PGC-1α decreased after the activation of AVICs induced by TGF-β1 (control group: 1.00±0.18; 24 h: 0.31±0.10; 48 h: 0.32±0.06; 72 h: 0.20±0.07; P<0.05). Specific overexpression of PGC-1α by adenovirus inhibited the activation of AVICs induced by TGF-β1 stimulation (periostin: 3.17±0.64 vs. 1.45±0.54, P<0.05; α-smooth muscle actin: 0.77±0.11 vs. 0.28±0.06, P<0.05). On the contrary, inhibition of PGC-1α function by GW9662 promoted the activation of AVICs (periostin: 2.20±0.68 vs. 7.99±2.50, P<0.05). Subsequently, it was found that PGC-1α might inhibit the activation of AVICs through downregulating the expression of calcium/calmodulin-dependent protein kinase (CAMK1δ) (0.97±0.04 vs. 0.74±0.11, P<0.05), and downregulating the expression of CAMK1δ alleviated the activation of AVICs (periostin: 1.76±0.11 vs. 0.99±0.20, P<0.05). The possible mechanism was that the activation of mammalian target of rapamycin (mTOR) signaling pathway was inhibited by reducing the accumulation of reactive oxygen species (ROS) (778.3±139.4 vs. 159.3±43.2, P<0.05). Finally, the protective effect of PGC-1α overexpression was verified in the activated phenotype of human AVICs (periostin: 2.73±0.53 vs. 1.63±0.14, P<0.05; connective tissue growth factor: 1.27±0.04 vs. 0.48±0.09, P<0.05). Conclusions The expression of PGC-1α significantly decreases during the activation of AVICs induced by TGF-β1. The overexpression of PGC-1α significantly inhibites the activation of AVICs, suggesting that PGC-1α plays a protective role in the activation of AVICs. The possible mechanism is that PGC-1α can inhibit the activation of CAMK1δ-ROS-mTOR pathway. In conclusion, interventions based on PGC-1α expression levels are new potential therapeutic targets for aortic stenosis.
ObjectiveTo analyze the characteristics and cardiac anatomy of patients with conduction block after transcatheter aortic valve replacement (TAVR) with Venus-A valve.MethodsRetrospective analysis was conducted on the clinical data of patients with severe aortic stenosis who underwent TAVR with Venus-A valve in the Second Affiliated Hospital of Army Military Medical University from October 2017 to May 2020. According to the occurrence of heart conduction block after TAVR, the patients were divided into the blocked group and the unblocked group, and the differences in characteristics and cardiac anatomy between the two groups were compared.ResultsForty-nine patients with severe aortic stenosis were included in the analysis, including 29 in the blocked group and 20 in the unblocked group. The incidence of atrial fibrillation in the blocked group was higher than that in the unblocked group (P=0.015), and there was no statistically significant difference in other preoperative indicators (P>0.05). There was no statistically significant difference in postoperative indicators between the blocked group and the unblocked group (P>0.05). Among bicuspid aortic valve, the ellipticity of left ventricular outflow tract and annulus in the blocked group were higher than those in the unblocked group (P<0.05), and the ratio of the short diameter of the left ventricular outflow tract to the bottom diameter of the implanted valve was smaller than that of the unblocked group (t=2.225, P=0.043). There was no significant difference in other cardiac anatomical indicators (P>0.05). As to tricuspid aortic valve cases, there was no significant difference in cardiac anatomic parameters between the blocked group and the unblocked group (P>0.05).ConclusionsFor bicuspid aortic valve patients with severe aortic stenosis and implanted with Venus-A valve, larger elliptic rate of annulus or left ventricular outflow tract, smaller proportion of left ventricular outflow tract diameter to the bottom diameter of implanted valve are associated with conduction block after TAVR. These anatomical patterns might be used as potential clinical indicators to predict postoperative conduction block.
This paper discusses a female patient with severe aortic stenosis, who was preoperatively assessed to be at high risk of left coronary artery occlusion, but developed complete occlusion of the right coronary artery during the procedure of transcatheter aortic valve replacement, leading to hemodynamic disorder. Surgical treatment under emergency cardiopulmonary bypass played a critical role in rescuing the patient.
ObjectivesTo investigate simple assess method of the degree of low transvalvular gradient aortic stenosis patients with impaired left ventricular function and to investigate aortic valve replacement indications, short and mid-term outcome of this kind of patients. MethodsWe retrospectively analyzed the clinical data of 21 low-gradient patients with impaired left ventricular function in our hospital from January 2011 through May 2014. There were 15 males and 6 females aged 41-66 (54.6± 10.7) years with mean aortic transvalvular gradient less than 40 mm Hg and left ventricular ejection fraction (LVEF) less than 50%. ResultsIn response to dobutamine echocardiography stress test, 20 patients underwent aortic valve replacement. The result of intraoperative pathology showed 11 patients were with bicuspid aortic valve malformation, 4 patients with degenerative changes, 4 patients with rheumatic disease. During the same period, 3 patients underwent atrial fibrillation ablation, 1 patient with ascending aorta replacement, 2 patients with coronary artery bypass grafting, 1 patient with mitral valvuloplasty. One patient died of multiple organ failure on the fourth day after operation. The remaining patients recovered. The patients were followed up for 3 to 37 months after operation. Heart function of majority improved to gradeⅠorⅡin 3 months after surgery. The result of echocardiogram showed prosthetic valve function was good and LVEF increased (preoperative 35.7%± 8.2% vs. postoperative 49.4%± 7.2%). One patient suffered sudden death of unknown cause in the 11th months after operation. ConclusionsFor patients whose dobutamine echocardiography stress test displayed with true severe aortic stenosis and left ventricular contractile reserve capacity, after aortic valve replacement and relief of the obstruction, the left ventricular afterload decreases significantly, the left ventricular function also improves, LVEF and the quality of life improve significantly after operation.
Transcatheter aortic valve replacement (TAVR) is a minimally invasive approach to treat symptomatic severe aortic stenosis with surgical taboos or high risk. With the update of the guidelines, the indication of TAVR has been extended to the intermediate-risk aortic stenosis population, and even has a tendency to further expand to the low-risk population. This review highlights the research progress and new evidence of TAVR in respects of patient selection, valve and approach selection, ethnic differences, and surgical complications such as perivalvular leakage, cardiac conduction block, vascular complications, stroke, acute kidney injury, and coronary artery occlusion.
Nowadays, aortic bioprostheses are used more and more widely in clinical practice, but the valve will experience structural valve degradation over time, and eventually lose its function, which is valve failure. Valve failure has become a significant challenge for aortic valve replacement and especially limits the expansion of indications for transcatheter aortic valve replacement. This review focuses on the current status and relevant evidence on the definition, risk factors, epidemiological characteristics, diagnosis and evaluation, treatment strategies of aortic bioprostheses failure. The purpose is to provide a basis for a more comprehensive understanding of aortic bioprostheses failure, finding better coping strategies and further improving the long-term durability of the valve.
ObjectiveTo systematically review the efficiency and safety of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis at intermediate-low risk compared with surgical aortic valve replacement (SAVR).MethodsTwo researchers searched literatures independently in databases including PubMed, Embase, Scopus, Cochrane Library, China Biology Medicine disc, China National Knowledge Internet, VIP database for studies published from January 2012 to October 2017, then screened for propriate studies, collected information from different follow-up period all on the principle of Cocharan handbook. At last statistal analysis was performed in RevMan 5.3 to calculate relative risk (RR) and its 95% confidence interval (CI).ResultsThirteen studies were enrolled in this Meta-analysis with 10 753 patients, including 5 263 cases in TAVR group and 5 490 cases in SAVR group. Meta-analysis showed that there were no statistically significant differences in all-cause mortality between TAVR group and SAVR group in 30 days, 1 year or 2 years after operation [RR=0.96, 95%CI (0.75, 1.24), P=0.78; RR=0.84, 95%CI (0.68, 1.03), P=0.09; RR=0.97, 95%CI (0.84, 1.14), P=0.75]; while stroke more preferred SAVR no matter 30 days or 1 year [RR=0.64, 95%CI (0.51, 0.80), P<0.000 1;RR=0.76, 95%CI (0.63, 0.92), P=0.004].ConclusionThere is no significant difference in all-cause mortality of intermediate-low risk patients undergoing TAVR and SAVR, but TAVR perfoms better in terms of srtoke.
Due to the lack of calcification of the aortic valve, it is difficult to provide effective support for the fixation of artificial valve in aortic stenosis characterized by leaflet thickening. There is a risk of postoperative perivalvular leakage and secondary valve implantation, which is widely regarded as a relative contraindication for transcatheter aortic valve replacement (TAVR). But aortic valvuloplasty and self-expanding transcatheter aortic valve has showed its safety and efficacy. This paper reports a patient with bicuspid aortic valve characterized by leaflet thickening treated with TAVR. After the operation, the patient’s symptom of exertional dyspnea was significantly improved, New York Heart Association class increased to Ⅱ, no perivalvular leakage was found, and the mean transaortic pressure gradient and the maximum aortic valve velocity decreased significantly.
ObjectiveTo investigate clinical outcomes of aortic valve replacement (AVR)for surgical treatment of patients with severe aortic stenosis (AS)and left ventricular dysfunction (LVD). MethodsClinical data of 29 patients with severe AS and LVD (left ventricular ejection fraction (LVEF) < 0.50)who underwent AVR in Changhai Hospital between January 2000 and December 2011 were retrospectively analyzed. Patients with mitral stenosis were excluded from this study. There were 22 male and 7 female patients with their age of 14-76 (56.3±12.9)years. Preoperative and postoperative clinical and echocardiographic findings were compared to assess AVR effects. Possible risk factors affecting postoperative recovery of left ventricular function were analyzed according to postoperative LVEF changes. ResultsOne patient died within 30 days after AVR. In the other 28 patients, postoperative aortic pressure gradient (APG)decreased from 97.6±25.1 mm Hg to 25.0±9.7 mm Hg, while LVEF increased from 41%±6% to 56%±11%. Postoperative left ventricular end-diastolic/systolic diameter/volume all significantly improved (all P < 0.001). ConclusionsAVR is an effective treatment for patients with severe AS and LVD. Left ventricular function improves significantly in most patients after AVR. Patients with a less dilated left ventricle may have a better LVEF recovery.