The purpose of this paper is to report the research and design of control system of magnetic coupling centrifugal blood pump in our laboratory, and to briefly describe the structure of the magnetic coupling centrifugal blood pump and principles of the body circulation model. The performance of blood pump is not only related to materials and structure, but also depends on the control algorithm. We studied the algorithm about motor current double-loop control for brushless DC motor. In order to make the algorithm adjust parameter change in different situations, we used the self-tuning fuzzy PI control algorithm and gave the details about how to design fuzzy rules. We mainly used Matlab Simulink to simulate the motor control system to test the performance of algorithm, and briefly introduced how to implement these algorithms in hardware system. Finally, by building the platform and conducting experiments, we proved that self-tuning fuzzy PI control algorithm could greatly improve both dynamic and static performance of blood pump and make the motor speed and the blood pump flow stable and adjustable.
Algorithms ; Assisted Circulation ; instrumentation ; Fuzzy Logic ; Heart-Assist Devices ; Magnetic Phenomena ; Magnetics

This paper built the mathematical model of a centrifugal blood pump, which was designed by ourselves, combined it with that of the human cardiovascular system and simulated the coupling system using Matlab. Then we set up the experiment platform, linked the blood pump to mock human cardiovascular system in case of three-stage heart failure, and measured aortic pressure and flow under different speed. The comparison between experiment results and simulation results not only indicates the coupling model is correct and the blood pump works well, but also shows that with the increase of blood pump speed, the pulsation of aortic pressure and flow will be reduced, this situation will affect the structure and function of blood vessels.
Cardiovascular System ; Heart-Assist Devices ; Hemodynamics ; Humans ; Models, Theoretical

In order to achieve auxiliary timing of ventricular assisting device to automatically track the ECG signals, we designed a set of ECG acquisition circuit in our study for the first time. Then we carried out ECG acquisition, smoothing filter and QRS detection on the LabVIEW. With the QRS signal as a benchmark, the control system immediately triggered ventricular assisting device to trigger the heart to contract for ejection for about 300 ms, and then to assist to make it relax. The practical effects of the experiment proved that ECG acquisition circuit had the feature of strong anti-interference, and control system had no false QRS detection and no false triggering of assist device. This achieves the auxiliary timing which could automatically track the ECG signal.
Electrocardiography ; instrumentation ; Heart-Assist Devices ; Humans ; Signal Processing, Computer-Assisted ; instrumentation

Objective:To analyze the efficacy of second-line regimens and prognostic factors in patients with first-relapsed multiple myeloma (MM) treated with bortezomib, cyclophosphamide, and dexamethasone (BCD).Methods:A retrospective cohort study. Clinical data were collected in first-relapsed MM patients after BCD treatment from three tertiary hospitals in north China from July 2009 to October 2022. Patients were classified according to the second-line regimen into the immunotherapy group, single novel agent group [either proteasome inhibitor (PI) or immunomodulatory drug (IMiD)], combination treatment group (both PI+IMiD), and traditional treatment group. Responses to second-line regimens and survival data were analyzed. The Kaplan-Meier method was used for survival analysis and the Cox proportional risk model was used for univariate and multivariate analyses.Results:A total of 217 patients were enrolled including 8.8% (19/217) in the immunotherapy group, 48.4% (105/217) in the PI/IMiD group, 29.9% (65/217) in the PI+IMiD group, and 12.9% (28/217) in the traditional treatment group. The median age was 62 years (range 31-83 years) and 56.2% (122/217) were males. The overall response rates (ORRs) in the four groups were 94.7% (18/19) vs. 56.2% (59/105) vs. 73.8% (48/65) vs. 32.1% (9/28) ( χ2=24.55; P<0.001), respectively. The progression-free survival (PFS) of the second-line regimens (2ndPFS) was 17.7 vs. 9.0 vs. 9.2 vs. 4.6 months ( χ2=22.74; P<0.001), respectively, among which patients in the PI/IMiD and PI+IMiD groups had comparable 2ndPFS ( χ2=1.76; P=0.923). Patients with high-risk cytogenetic abnormalities (HRCAs) achieved the longest 2ndPFS of 22.0 months in the immunotherapy group ( χ2=15.03; P=0.002). Multivariate analysis suggested that immunotherapy ( HR=0.11, 95% CI 0.05-0.27), achievement of efficacy of partial response or better ( HR=0.47, 95% CI 0.34-0.66), and non-aggressive relapse ( HR=0.25, 95% CI 0.17-0.37) were independent prognostic factors of 2ndPFS. Conclusion:In this real-world study, immunotherapy was associated with a more favorable efficacy and PFS for first-relapsed MM patients after BCD treatment, with similar outcomes in patients with HRCAs.

To investigate the value of injecting a small amount of absolute ethanol into the benign solid nodules of the thyroid before radiofrequency ablation(RFA)to improve the efficiency of radiofrequency ablation. A total of 98 eligible patients(98 nodules)with pathologically confirmed benign solid nodules who were treated in our center from December 2016 to February 2018 were included and randomized into ethanol ablation(EA)combined with radiofrequency ablation(RFA)group(EA+RFA group)and RFA group,with 49 patients in each group.Routine ultrasound,contrast-enhanced ultrasound(CEUS),and thyroid function test were performed before treatment and 1,3,6,and 12 months after treatment.The general information,treatment time,ablation energy,ablation power,postoperative nodule volume reduction ratio(VRR),symptom score(SS)and cosmetic score(CS),thyroid function level,and incidence of complications were compared between these two groups. The mean treatment time [(441.30±243.31)s (790.70±349.82)s;= 4.403, =0.000],mean ablation energy [(3.92±2.01)kJ (5.15±2.12)kJ;=2.709, =0.009],and mean ablation power [(6.07±1.44)W (7.30±1.29)W;=3.612, =0.006] were significantly lower in the EA+RFA group than in the RFA group.At 3,6 and 12 months after surgery,the VRR in the EA+RFA group was(57.73±11.07)%(=-3.16, <0.001),(64.40±10.56)%(=-5.45, <0.001),and(77.29±8.48)%(=-10.46, <0.001),respectively;the VRR in the RFA group was(55.44±13.01)%(=-1.76, <0.001),(65.28±11.33)%(=-5.09, <0.001),and(75.17±9.84)%(=-8.93, <0.001),which were significantly smaller than those before surgery.There was no significant difference in VRR between the EA+RFA group and the RFA group at 1(=3.41, =0.33),3(=2.05, =0.21),6(=2.77, =0.49),and 12 months(=5.05, =0.10)after treatment.During the follow-up,no recurrence of nodules was observed on CEUS.In the EA+RFA group,the SS [(1.77±0.86).(5.54±2.15);=9.63, <0.001] and the CS[(1.39±0.77).(3.32±0.61);=10.09, =0.004]at 12 months after surgery were significantly lower than those before surgery.In the RFA group,SS [(1.63±1.04).(5.90±1.79);=12.72, <0.001] and CS [(1.64±0.83).(3.15±0.72);=8.13, =0.012] at 12 months after surgery were also significantly lower than those before surgery.The CSS in the EA+RFA group was significantly lower than that in the RFA group [(0.93±0.55).(2.44±0.53);=-11.70, =0.007].Both groups had no significant change in thyroid function during the follow-up period,and no serious complications were observed. Anhydrous alcohol injection can effectively improve the efficiency of radiofrequency ablation in treating benign solid thyroid nodules and is effective in reducing nodule volume,alleviating compressive symptoms,and decreasing cosmetic discomfort.
Catheter Ablation ; Ethanol ; Humans ; Neoplasm Recurrence, Local ; Prospective Studies ; Thyroid Nodule ; Treatment Outcome