Search

Objective To evaluate the effect of multilevel single-shot thoracic paravertebral blockade (PVB) on the occurrence of chronic postsurgical pain (CPSP) in patients undergoing breast cancer surgery. Design A randomized controlled trial with two parallel groups. Setting A tertiary hospital. Methods Patients scheduled for breast cancer surgery were randomized to receive either ultrasound-guided multilevel single-shot PVB from T2 to T5 (the PVB group) or nothing (the control group). Surgery was then performed under general anesthesia. Patients were followed up for 12 months after surgery. The primary end point was incidence of CPSP at six months after surgery. Results A total of 218 patients were enrolled and randomized; of these, 208 and 204 completed six- and 12-month follow-up, respectively. The incidence of CPSP at six months was significantly lower in the PVB group (12.5% [13/104]) than in the control group (24.0% [25/104], relative risk = 0.52, 95% CI = 0.28–0.96, P = 0.031). Pain scores within 48 hours both at rest and with movement were lower in the PVB group than the control group (P = 0.006 and P Conclusions For patients undergoing breast cancer surgery, multilevel single-shot PVB reduces the incidence of CPSP at six months; it also improves early postoperative analgesia and reduces neuropathic pain at six and 12 months after surgery.

Growing evidence have demonstrated that thyroid hormones have been involved in the processes of cardiovascular metabolism. However, the causal relationship of thyroid function and cardiometabolic health remains partly unknown.The Mendelian randomization (MR) was used to test genetic, potentially causal relationships between instrumental variables and cardiometabolic traits. Genetic variants of free thyroxine (FT4) and thyrotropin (TSH) levels within the reference range were used as instrumental variables. Data for genetic associations with cardiometabolic diseases were acquired from the genome-wide association studies of the FinnGen, CARDIoGRAM and CARDIoGRAMplusC4D, CHARGE, and MEGASTROKE. This study was conducted using summary statistic data from large, previously described cohorts. Association between thyroid function and essential hypertension (EHTN), secondary hypertension (SHTN), hyperlipidemia (HPL), type 2 diabetes mellitus (T2DM), ischemic heart disease (IHD), myocardial infarction (MI), heart failure (HF), pulmonary heart disease (PHD), stroke, and non-rheumatic valve disease (NRVD) were examined.Genetically predicted FT4 levels were associated with SHTN (odds ratio = 0.48; 95% CI = 0.04-0.82,Our study suggests FT4 and TSH are associated with cardiometabolic diseases, underscoring the importance of the pituitary-thyroid-cardiac axis in cardiometabolic health susceptibility.

The role of uric acid (UA) in survival of patients with hypertrophic obstructive cardiomyopathy (HOCM) has not been fully evaluated. This study aimed to determine whether UA could be an independent risk factor of cardiac death in patients with HOCM.A total of 317 patients with HOCM, who were receiving conservative treatment in Fuwai Hospital from October 2009 to December 2014, all of them completed UA evaluations, were analyzed. Patients were divided into three groups according to the UA levels: Tertile 1 (≤ 318 μmol/L,During a median follow-up of 45 months, 29 cardiac deaths (9.1%) occurred, including 6 sudden cardiac deaths and 23 heart failure-related deaths. Cardiac death in Tertile 3 (UA concentration was found to be independently associated with cardiac death in HOCM patients receiving conservative treatment. Randomized trials of UA-lowering agents for HOCM patients are warranted.

For the estimation of frequency response function (FRF) using the window-based spectral estimation method, the error models of the FRF estimation are introduced, including window interpolation error and transient error models, and an error model-based iterative compensation (EMIC) method is then proposed to improve the FRF estimation accuracy. The specific iteration steps of the proposed EMIC method are presented, fast computations are adopted in the steps as far as possible; and that, iteration convergence and noise uncertainty are analyzed. The analyses reveal that, the proposed EMIC method is almost always convergent as long as the error of the FRF pre-estimation is small, intercepting enough data and using a window which has smaller and fewer side DFT bins as well as smaller front-end value for FRF estimation can result in better iteration convergence; whereas, the proposed EMIC method will slightly increase the noise uncertainty of FRF estimation compared with that without iterative compensation because it removes the window interpolation effects on noise just like removing the error. To verify the effectiveness and practicability of the proposed EMIC method, model simulation and actual sensor data verification are implemented, and multi existing methods are employed for comparison. The results show that, the proposed EMIC method can largely decrease the error of the FRF estimated by the window-based spectral estimation method, it has the best maximum error restraining capabilities especially in the resonance frequency band and relatively better comprehensive error restraining capabilities especially when the data is not long enough compared with the mentioned existing methods, also, the time consumption of the proposed EMIC method is acceptable and is usually seconds or less; and that, the theoretical analyses, model simulation results and actual data verification results are consistent with each other. Consequently, the proposed EMIC method is proven to be effective and practical for improving the FRF estimation of a stable LTI system from its step or impulse response data.

The sinusoidal signal outputted by the vortex flow sensor is often superimposed with the white noise, which will affect the accuracy of spectrum correction. When the signal is truncated by rectangular window, a method (hereinafter referred to as RWBWFCR) combining bilateral correction with weighted average on the basis of Fourier coefficients ratio is proposed so as to improve the antinoise performance of the frequency correction. The correction principle of this method is presented. The effects on the frequency correction of changing the initial phase, the frequency deviation, the calculation points of fast Fourier transform, and the signal-to-noise ratio (SNR) are analyzed. The theoretical accuracy of this method when there is stationary Gaussian white noise is deduced and verified. This method has some advantages, such as less computation load, small storage space, high correction precision, strong anti-interference ability, and is easy to be implemented by a microcontroller in real time. RWBWFCR method is applied to the low-power and antivibration type vortex flowmeter with single sensor to improve the reliability of the digital signal processing method based on the frequency correction.

Vortex flowmeter is installed in piping to measure the fluid flow rate. The piping is easily disturbed by strong transient impact in the application fields, such as other components impacting on the pipeline, manual knocking on the pipe, and opening and closing of valves. The strong transient impact will be picked up by the vortex flow sensor, which makes the vortex flowmeter output wrong measurement results. The current commonly used digital signal processing method can do nothing about it. To solve this problem, an experimental setup is built in our laboratory to study the impact interference, and a large number of vortex flow sensor output signals are collected. The characteristics of transient impacts outputted by the vortex sensor are analyzed so as to describe this type of signal quantitatively. The pattern of transient impact is that the signal amplitudes increase suddenly and then attenuate gradually. A segmented Kalman filter based digital signal processing method is proposed according to this pattern. The data segment containing strong transient impact is found first; the transient impact power is reduced by filtering the data segment second; and through spectral analysis of the filtered signal, the maximum peak of the spectrum is extracted as the vortex flow signal finally. The algorithm is implemented in real time by a low-power microcontroller. Both gas and water flow experiments have been conducted to verify the validity and reliability of the antistrong transient impact algorithm.

To solve the key problem that vortex flowmeter is susceptible to be disturbed by pipe vibration, the collected data of the vortex flow sensor output signal are filtered, and the amplitudes of the filtered signal are extracted. The fluctuations of both the amplitude and frequency are analyzed and compared so as to study antistrong vibration interference digital signal processing methods for vortex flowmeter. The patterns of fluctuation features are extracted by calculating and analyzing the probability density function and the cycle differenced sequence. Combining with the features of the amplitude modulation and frequency modulation, the mathematical models of the vortex signal, vibration interference, and cofrequency signal are built, and the patterns between the frequency and model parameters are obtained. The effectiveness of the three types of signal models is verified through error analysis, then the reliability of the fluctuation patterns of signal amplitude and frequency is examined, which provides the basis for digital signal processing methods based on fluctuation features.

To assess the condition of left ventricular outflow tract obstruction (LVOTO) under resting conditions and physiological exercise in hypertrophic cardiomyopathy (HCM) patients.A total of 60 patients with HCM and left ventricular outflow tract gradient (LVOTG)50 mm Hg (1 mm Hg = 0.133 kPa) at rest were enrolled consecutively, and LVOTG at rest and exercise were measured by echocardiography. Of 51 patients with gradients30 mm Hg at rest, 26 were latent LVOTO with exercise peak value LVOTG ≥ 30 mm Hg, 25 were non LVOTO with exercise peak value LVOTG30 mm Hg, and 9 were resting obstruction with LVOTG 30-49 mm Hg. The morphological characteristics of different types of obstruction were analyzed.Patients with latent LVOTO were more likely to have SAM (73.1% vs 8.0%) , narrow of LVOT (46.2% vs 4.0%) , higher resting gradients [(16.9 ± 7.2) mm Hg vs (7.1 ± 4.3) mm Hg] and mitral regurgitation grade at rest than patients with non-obstructive (all P values0.05). The distribution of septal hypertrophy were different in the two groups (P0.05). Multivariate logistic regression analysis showed independent predictors of latent LVOTO were SAM (OR 6.431, 95%CI 2.323-291.112, P = 0.002) at rest and distribution of septal hypertrophy(OR 0.011, 95% CI 0.001-0.179, P = 0.008).Approximately half of patients with non-obstructive HCM at rest have latent LVOTO. SAM and distribution of septal hypertrophy may be useful to identify patients with latent obstruction.

To compare left ventricular outflow tract (LVOT) gradient induced by dobutamine stress echocardiography (DSE) and exercise echocardiography (EE) in patients with hypertrophic cardiomyopathy (HCM).DSE and EE were performed in 40 consecutive patients with HCM and LVOT gradient50 mm Hg (1 mm Hg = 0.133 kPa) at rest. Dobutamine was administered intravenously at incremental doses of 200, 400, 600, 800 and 1200 µg/min at 5 min intervals. LVOT gradients were measured at rest, at peak exercise and during each dose of DSE.LVOT gradient at rest was lower than 30 mm Hg in 36 patients and between 30 and 49 mm Hg in 4 patients. Of the 36 patients with LVOT gradient30 mm Hg at rest, mechanical LVOT obstruction (latent LVOTO) was evidenced in 17 patients during EE and in 18 patients during DSE and good consistency (91.7%, kappa value 0.833) was found between the two maneuvers. The provoked gradient was similar between DSE at 800 µg/min and EE at peak exercise (P = 0.181). In the 4 patients with LVOT gradient between 30 and 49 mm Hg [(38.8 ± 2.6) mm Hg], LVOT gradient increased to (85.3 ± 26.4) mm Hg during EE and (105.0 ± 28.0) mm Hg during DES.DES and EE are comparable and suitable provoke methods for identifying LVOT obstruction in patients with HCM.

To investigate the effect and safety of early intervention and delayed intervention therapy on elderly patients and younger patients with non-ST segment elevation acute coronary syndrome.The patients with non-ST segment elevation acute coronary syndrome were randomly divided into early intervention group (coronary angiography taken within 24 hours after grouping) and delayed intervention group (coronary angiography taken after 36 hours after grouping). The primary endpoint was a composite endpoint of death, myocardial infarction and stroke during 180 days follow-up.A total of 815 patients were enrolled, including 198 elderly patients aged 75 years and above, and 617 younger patients aged below 75 years. The elderly patients had a greater incidence of the primary endpoint than that of younger patients (P = 0.00). The primary endpoint of early intervention group were obviously lower than that of delayed intervention group of younger patients (P = 0.01). There was no significant difference in primary endpoint incidence of early intervention group and delayed intervention group of the elderly patients (P = 0.39).The elderly patients with non-ST segment elevation acute coronary syndrome who underwent intervention had greater incidence of death and myocardial infarction. Early intervention reduced the rate of myocardial infarction for the younger patients. There was no significant difference in primary endpoint incidence between early intervention and delayed intervention among elderly patients.

To determine gender differences in baseline characteristics and intervention treatment in relation to prognosis in patients with non-ST segment elevation acute coronary syndrome (NSTEACS).A total of 814 patients (545 men and 269 women) with NSTEACS were randomized to early intervention (coronary angiography24 hours after randomization) or delayed intervention (coronary angiography36 hours after randomization). The primary outcome was a composite of death, myocardial infarction, or stroke at 6 months.Women were older and more frequently had hypertension, diabetes, and history of coronary artery disease (CAD) or chronic angina (P0.05 for all). Women less were smokers and had elevations in cardiac marker (P0.05 for both). Women who underwent angiography had no significant lesions more often, but the left main stem and/or three-vessel diseases were similar with men. In adjusted multiple logistic regression analysis, the previous myocardial infarction and severe coronary artery disease were independently associated with the risk of primary endpoint in women. On multivariate analysis for men, severe coronary artery disease delayed intervention strategy and at least 3 risk factors for CAD were independently associated with the risk of primary endpoint.In NSTEACS patients, different gender had the different prognostic predictor. Severe coronary diseases were as an independent predictor for both male and female patients. An early intervention strategy resulted in a beneficial effect in men which was not seen in women.