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        find Keyword "left ventricular" 51 results
        • Value of transthoracic echocardiography to monitor and evaluate aortic insufficiency after implantation of left ventricular assist device

          ObjectiveTo explore the value of transthoracic echocardiography (TTE) to monitor and evaluate aortic insufficiency (AI) within one year after the implantation of the left ventricular assist device (LVAD).MethodsWe retrospectively collected and analyzed the TTE data of 12 patients who received LVAD implantation from 2018 to 2020 in our hospital. All patients were males, with an average age of 43.3±8.6 years. We analyzed temporal changes in the aortic annulus (AA), aortic sinus (AoS), ascending aorta (AAo), the severity of AI and the opening of aortic valve before operation and 1 month, 3 months, 6 months and 12 months after LVAD implantation.ResultsAll 12 patients survived within 1 year after LVAD implantation. One patient was bridged to heart transplantation 6 months after implantation, and two patients did not receive TTE after 3 and 6 months. Compared to pre-implantation, AoS increased at 1 month after implantation (31.58±5.09 mm vs. 33.83±4.69 mm). The inner diameters of AA, AoS and AAo increased at 3, 6 and 12 months after LVAD implantation compared to pre-implantation (P<0.05), but all were within the normal range except for one patient whose AoS slightly increased before operation. After LVAD pump speed was adjusted, the opening of aortic valve improved. The severity of AI increased at 6 and 12 months after LVAD implantation compared to pre-implantation, and increased at 12 months compared to 6 months after LVAD implantation (P<0.05).ConclusionTTE can evaluate aortic regurgitation before and after LVAD implantation and monitor the optimization and adjustment of LVAD pump function, which has a positive impact on the prognosis after LVAD implantation.

          Release date:2021-07-02 05:22 Export PDF Favorites Scan
        • Evaluating the Left Ventricular Diastolic Function of Diabetes Mellitus Patients Using Dual-gate Doppler

          To evaluate the value of left ventricular diastolic function in type 2 diabetes mellitus (DM) using dual-gate Doppler and relative factors, we included 50 non-obesity and hypertension-free DM patients into the controlled group in the study along with 48 age-and-gender-matched healthy volunteer subjects. The peak early diastolic velocity (E), peak later diastolic velocity (A), deceleration time (DT), anterior mitral annulus diastolic peak velocity (e'), isovolumic relaxation time (IVRT), E/A, E/e', Tei index and TE-e' were measured with dual-gate Doppler. 20 subjects were randomly selected for repetitive analysis. Study showed statistical difference in E/A, DT, e', E/e', IVRT, Tei index and TE-e' between the two groups (P < 0.05). Linear regression analysis showed positive correlation between TE-e' and IVRT, course of DM patients and TE-e'(Beta=0.295, P=0.020), and HbA1C control level and TE-e'(Beta=0.399, P=0.010). Repeated analysis showed good reproducibility for both within and between groups. Dual-gate Doppler has clinical value in evaluating left ventricular diastolic function in type 2 diabetes mellitus patients. The course of type 2 diabetes mellitus patients and HbA1C control level were both closely related with left ventricular diastolic function.

          Release date:2021-06-24 10:16 Export PDF Favorites Scan
        • Risk factors for death after one-stage radical surgery in children with interruption of aortic arch and ventricular septal defect

          Objective To analyze the risk factors for death in children with interruption of aortic arch (IAA) and ventricular septal defect (VSD) after one-stage radical surgery. Methods A retrospective analysis was performed on patients with IAA and VSD who underwent one-stage radical treatment in the First Hospital of Hebei Medical University from January 2006 to January 2017. Cox proportional hazards regression model was used to analyze the risk factors for death after the surgery. Results A total of 152 children were enrolled, including 70 males and 82 females. Twenty-two patients died with a mean age of 30.73±9.21 d, and the other 130 patients survived with a mean age of 37.62±11.06 d. The Cox analysis showed that younger age (OR=0.551, 95%CI 0.320-0.984, P=0.004), low body weight (OR=0.632, 95%CI 0.313-0.966, P=0.003), large ratio of VSD diameter/aortic root diameter (VSD/AO, OR=2.547, 95%CI 1.095-7.517, P=0.044), long cardiopulmonary bypass time (OR=1.374, 95%CI 1.000-3.227, P=0.038), left ventricular outflow tract obstruction (LVOTO, OR=3.959, 95%CI 1.123-9.268, P=0.015) were independent risk factors for postoperative death. Conclusion For children with IAA and VSD, younger age, low body weight, large ratio of VSD/AO, long cardiopulmonary bypass time and LVOTO are risk factors for death after one-stage radical surgery.

          Release date:2024-09-20 12:30 Export PDF Favorites Scan
        • Original Study of A Long-term Aortic Valve Pump of 23mm Outer Diameter, Weighing 31g

          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.

          Release date:2016-08-30 06:22 Export PDF Favorites Scan
        • Prognosis of the complete transposition of great arteries with left ventricular outflow tract obstruction after intraventricular repair

          Objective To compare the clinical characteristics and prognosis of patients who received two different intraventricular repair. Methods We retrospectively analyzed the clinical data of 24 complete transposition of the great arteries (TGA)/left ventricular outflow tract obstruction (LVOTO) patients who all received intraventricular repair. The patients were allocated into two groups including a REV group and a Rastelli group. There were 13 patients with 9 males and 4 females at median age of 25.2 (6, 72) months in the REV group. There were 11 patients with 10 males and 1 female at median age of 47.9 (14, 144) months in the Rastelli group. Results The age at operation (P=0.041), pulmonary valve Z value (P=0.002), and LVOT gradient (P=0.004), rate of multiphase operation between the REV group and the Rastelli group was statistically different. The mean follow-up time was 17.3 months. And during the follow-up, 1 patient had early mortality, 2 patients had early reintervention, 7 patients had postoperative RVOTO, and received Rastelli and larger VSD inner diameter were associated with postoperative RVOTO. Conclusion As the traditional surgery for TGA/LVOTO patients, the intraventricular repair has a low early mortality and low early reintervention. Modified REV is associated with postoperative peripheral pulmonary vein isolation (PVIS). Patients who received Rastelli operation and with larger VSD inner diameter are more likely to have postoperative RVOTO, but the reintervention for PVI and RVOTO during follow up is very low.

          Release date:2019-05-28 09:28 Export PDF Favorites Scan
        • Study on regurgitation using the coupling model of left ventricular assist device and cardiovascular system

          Regurgitation is an abnormal condition happens when left ventricular assist devices (LVADs) operated at a low speed, which causes LVAD to fail to assist natural blood-pumping by heart and thus affects patients’ health. According to the degree of regurgitation, three LVAD’s regurgitation states were identified in this paper: no regurgitation, slight regurgitation and severe regurgitation. Regurgitation index (RI), which is presented based on the theory of dynamic closed cavity, is used to grade the regurgitation of LVAD. Numerical results showed that when patients are in exercising, resting and sleeping state, the critical speed between slight regurgitation and no regurgitation are 6 650 r/min, 7 000 r/min and 7 250 r/min, respectively, with corresponding RI of 0.401, 0.300 and 0.238, respectively. And the critical speed between slight regurgitation and severe regurgitation are 5 500 r/min, 6 000 r/min and 6 450 r/min, with corresponding RI of 0.488, 0.359 and 0.284 respectively. In addition, there is a negative relation correction between RI and rotational speed, so that grading the LVAD’s regurgitation can be achieved by determining the corresponding critical speed. Therefore, the detective parameter RI based on the signal of flow is proved to be able to grade LVAD’s regurgitation states effectively and contribute to the detection of LVAD’s regurgitation, which provides theoretical basis and technology support for developing a LVADs controlling system with high reliability.

          Release date:2017-10-23 02:15 Export PDF Favorites Scan
        • Changes of left ventricular structure and function after minimally invasive repair of mitral valve prolapse

          ObjectiveTo evaluate the changes of left ventricular structure and function by echocardiography and its grading of left ventricular diastolic function in patients with mitral valve prolapse treated by minimally invasive mitral valve repair.MethodsBy retrospective analysis, 37 patients including 25 males and 12 females aged 53.49±11.02 years with mitral valve prolapse who underwent minimally invasive mitral valve repair were as an operation group, and 34 healthy persons including 19 males and 15 females aged 54.26±8.33 years matched by age and sex were selected as a control group. Ultrasound parameters of every participant were routinely collected before operation, 1 month, 3 months, 6 months and 1 year after operation, and left ventricular diastolic function was graded. The ultrasound parameters between the two groups were compared.ResultsThe diameters of left ventricular end systolic and diastolic phase, left atrial diameter and left ventricular volume in the operation group were significantly smaller than those before operation. The diameters of left ventricle and left atrium after operation were significantly shorter than those before operation, but they were still larger than those of the control group. The ejection fraction value decreased significantly at one month after the operation and then returned to normal level. The incidence of left ventricular diastolic dysfunction at 6 months and 1 year after operation was significantly lower than that before operation (P<0.05).ConclusionMinimally invasive repair for patients with mitral valve prolapse can significantly improve systolic and diastolic functions of left ventricle while reconstructing left atrial and left ventricular structures.

          Release date:2019-09-18 03:45 Export PDF Favorites Scan
        • Dissipative energy loss within the left ventricle detected using vector flow mapping technology in hypertension

          We have tried to explore the energy loss (EL) within the left ventricle in hypertension by using vector flow mapping (VFM) to detect left ventricular hemodynamic changes in hypertensive patients as early as possible and reflect changes of left ventricular function in hypertension by using EL. Twenty-one hypertensive patients with increased left ventricle mass index (LVMI), 14 hypertensive patients with normal LVMI and 22 control subjects were enrolled in this study. Systolic and diastolic EL derived from VFM within the left ventricle and E/e' by dual Doppler were recorded and analyzed. Compared with those of the controls, diastolic and systolic EL were significantly increased in hypertensive group (P<0.05). In diastole, EL=0.439×SBP (systolic blood pressure)–8.349; in systole, EL=0.385×SBP+0.644×LVMI–10.854. And the EL was positively correlated with E/e', but there was no significant correlation between EL and ejection fraction (EF) in the pooled population. The study shows that the increased EL can help us detect changes of left ventricular hemodynamic in hypertensive patients. It needs further investigation to prove whether EL within the left ventricle could be a new parameter to evaluate diastolic function. SBP and LVMI are the independent predictors for systolic EL, while SBP is the independent predictor for diastolic EL.

          Release date:2017-04-13 10:03 Export PDF Favorites Scan
        • Analysis of the risk factors for extracorporeal membrane oxygenation use after surgical repair in patients with anomalous origin of the left coronary artery from the pulmonary artery combined with severe left ventricular dysfunction

          ObjectiveTo analyze the early outcomes of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) patients with severe left ventricular dysfunction after surgical repair, and to explore the predictors for extracorporeal membrane oxygenation (ECMO) support for these patients.MethodsThe clinical data of ALCAPA patients with severe left ventricular dysfunction (left ventricular ejection fraction<40%) who underwent coronary artery reimplantation in the pediatric center of our hospital from 2013 to 2020 were retrospectively analyzed. The patients were divided into an ECMO group and a non-ECMO group. Clinical data of the two groups were compared and analyzed.ResultsA total of 64 ALCAPA patients were included. There were 7 patients in the ECMO group, including 4 males and 3 females aged 6.58±1.84 months. There were 57 pateints in the non-ECMO group, including 30 males and 27 females aged 4.34±2.56 months. The mortality of the patients was 6.25% (4/64), including 2 patients in the ECMO group, and 2 in the non-ECMO group. The postoperative complications rate was significantly higher in the ECMO group than that in the non-ECMO group (P=0.041). There were statistical differences in the cardiopulmonary bypass time [254 (153, 417) min vs. 106 (51, 192) min, P=0.013], aortic cross-clamping (ACC) time (89.57±13.66 min vs. 61.58±19.57 min, P=0.039), and preoperative left ventricular end-diastolic diameter/body surface area (132.32±14.71 mm/m2 vs. 108.00±29.64 mm/m2, P=0.040) between the two groups. Multivariate logistic regression analysis showed that ACC time was an independent risk factor for postoperative ECMO support (P=0.005). Receiver operating characteristic (ROC) curve analysis showed that the area under the ROC curve was 0.757, the sensitivity was 85.70%, specificity was 66.70%, with the cut-off value of 66 min.ConclusionACC time is an independent risk factor for postoperative ECMO support. Patients with an ACC time>66 min have a significantly higher risk for ECMO support after the surgery.

          Release date:2023-03-24 03:15 Export PDF Favorites Scan
        • A prediction model for long-term death in patients with acute myocardial infarction and reduced left ventricular ejection fraction

          Objective To explore the risk factors for long-term death of patients with acute myocardial infarction (AMI) and reduced left ventricular ejection fraction (LVEF), and develop and validate a prediction model for long-term death. Methods This retrospective cohort study included 1013 patients diagnosed with AMI and reduced LVEF in West China Hospital of Sichuan University between January 2010 and June 2019. Using the RAND function of Excel software, patients were randomly divided into three groups, two of which were combined for the purpose of establishing the model, and the third group was used for validation of the model. The endpoint of the study was all-cause mortality, and the follow-up was until January 20th, 2021. Cox proportional hazard model was used to evaluate the risk factors affecting the long-term death, and then a prediction model based on those risk factors was established and validated. Results During a median follow-up of 1377 days, 296 patients died. Multivariate Cox regression analysis showed that age≥65 years [hazard ratio (HR)=1.842, 95% confidence interval (CI) (1.067, 3.179), P=0.028], Killip class≥Ⅲ[HR=1.941, 95%CI (1.188, 3.170), P=0.008], N-terminal pro-brain natriuretic peptide≥5598 pg/mL [HR=2.122, 95%CI (1.228, 3.665), P=0.007], no percutaneous coronary intervention [HR=2.181, 95%CI (1.351, 3.524), P=0.001], no use of statins [HR=2.441, 95%CI (1.338, 4.454), P=0.004], and no use of β-blockers [HR=1.671, 95%CI (1.026, 2.720), P=0.039] were independent risk factors for long-term death. The prediction model was established and patients were divided into three risk groups according to the total score, namely low-risk group (0-2), medium-risk group (4-6), and high-risk group (8-12). The results of receiver operating characteristic curve [area under curve (AUC)=0.724, 95%CI (0.680, 0.767), P<0.001], Hosmer-Lemeshow test (P=0.108), and Kaplan-Meier survival curve (P<0.001) showed that the prediction model had an efficient prediction ability, and a strong ability in discriminating different groups. The model was also shown to be valid in the validation group [AUC=0.758, 95%CI (0.703, 0.813), P<0.001]. Conclusions In patients with AMI and reduced LVEF, age≥65 years, Killip class≥Ⅲ, N-terminal pro-brain natriuretic peptide≥5598 pg/mL, no percutaneous coronary intervention, no use of statins, and no use of β-blockers are independent risk factors for long-term death. The developed risk prediction model based on these risk factors has a strong prediction ability.

          Release date:2022-04-25 03:47 Export PDF Favorites Scan
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