Objective To identify the heart sounds of aortic stenosis by deep learning model based on DenseNet121 architecture, and to explore its application potential in clinical screening aortic stenosis. Methods We prospectively collected heart sounds and clinical data of patients with aortic stenosis in Tianjin Chest Hospital, from June 2021 to February 2022. The collected heart sound data were used to train, verify and test a deep learning model. We evaluated the performance of the model by drawing receiver operating characteristic curve and precision-recall curve. Results A total of 100 patients including 11 asymptomatic patients were included. There were 50 aortic stenosis patients with 30 males and 20 females at an average age of 68.18±10.63 years in an aortic stenosis group (stenosis group). And 50 patients without aortic valve disease were in a negative group, including 26 males and 24 females at an average age of 45.98±12.51 years. The model had an excellent ability to distinguish heart sound data collected from patients with aortic stenosis in clinical settings: accuracy at 91.67%, sensitivity at 90.00%, specificity at 92.50%, and area under receiver operating characteristic curve was 0.917. Conclusion The model of heart sound diagnosis of aortic stenosis based on deep learning has excellent application prospects in clinical screening, which can provide a new idea for the early identification of patients with aortic stenosis.
Transcatheter aortic valve replacement (TAVR) as a mature technology has been widely applied in Western countries. In China, with the first two domestic prostheses being approved for commercial use, the technology now is expecting a fast development. In this article, we reviewed the features of Chinese aortic stenosis patients, the early Chinese experience of TAVR, the application of domestic prostheses and remaining problems.
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.
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.
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.
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.
Valvular heart disease (VHD) is a common cardiac disease. Patients with severe VHD have a poor prognosis. With the development of minimal invasive treatments in VHD, especially with the wide application of transcatheter aortic valve replacement in aortic stenosis, these diseases have been regained attention. The disease spectrum and modes of treatment have also changed. However, we currently lack a large population-based VHD-related epidemiologic study in China. In this article, we will summarize the current status of VHD in China using available epidemiologic data.
It has been 20 years since the first transcatheter aortic valve replacement (TAVR) was performed internationally in 2002, and the development of TAVR technology in China has also been more than 10 years. The reliability of TAVR has been clinically proven, and it has also brought good benefits to patients with aortic stenosis. With the gradual progress of technology, TAVR has a trend to surpass surgical aortic valve replacement and become the mainstream surgery for patients with aortic stenosis. This article will review the relevant issues in the development of TAVR technology in recent years, based on existing research, and provide certain clinical references for the future development of TAVR technology.
Objective To systematically evaluate the impact of pulmonary hypertension (PH) on the prognosis of patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Methods A computerized search was conducted in CNKI, Wanfang Data, VIP, CBM, PubMed, The Cochrane Library, EMbase, and Web of Science databases from inception to June 2023 for cohort studies on the prognostic impact of PH in severe AS patients undergoing TAVR. Two researchers independently screened the literature, extracted data, and assessed the quality of included studies. Stata 17.0 software was used for meta-analysis. Results A total of 16 cohort studies were included, all with Newcastle-Ottawa Scale scores≥7. Meta-analysis results showed that, compared with AS patients without PH, those with PH had significantly higher 1-year all-cause mortality after TAVR [OR=2.10, 95%CI (1.60, 2.75), P<0.01], 30-day all-cause mortality [OR=2.09, 95%CI (1.54, 2.83), P<0.01], and cardiovascular mortality [OR=1.49, 95%CI (1.18, 1.90), P<0.01]. The differences between the two groups in major bleeding events, stroke, myocardial infarction, pacemaker implantation, and postoperative renal failure were not statistically significant. For outcome indicators with significant heterogeneity, subgroup analyses were performed based on PH measurement methods, diagnostic criteria, and different types of PH. The results showed that most subgroup combined results were consistent with the overall findings and that heterogeneity was significantly reduced. Conclusion PH significantly increases the 30-day all-cause mortality, 1-year all-cause mortality, and cardiovascular mortality in patients with severe AS undergoing TAVR.
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.
