Counterpulsation Research Articles

Efficacy Study of Fault Trending Algorithm to Prevent Fault Occurrence on Automatic Trampoline Webbing Machine

Nowadays, fault diagnostics is widely applied under Industry 4.0 to reduce machine maintenance costs, improve productivity, and increase machine availability. However, fault diagnostics are mostly post-mortem. When the fault is identified, it is already too late because damages have been done to the product and machine. This paper compares the efficacy of several signal data processing techniques for detecting faults that are about to occur. Our aim is to find an efficient way to predict the fault before it occurs. A continuous wavelet transform synchrosqueezed scalogram was found to be most suitable for this purpose, but it is difficult to apply. A novel procedure is proposed to count the number of pulses in the synchrosqueezed scalogram. A new method for detecting the trend from the pulse counts is then developed to predict the fault before it happens. The procedure and method are illustrated with experimental data collected while running an automated double-thread trampoline webbing machine.

Echocardiographic evaluation of patients with diastolic dysfunction of the left ventricle treated with external counterpulsation

Abstract Funding Acknowledgements Type of funding sources: None. Background The influence of the external counterpulsation (ECP, EECP) on patients with diastolic dysfunction of the left ventricle (LV) is unclear. We aim to determine whether external counterpulsation therapy improves echocardiographic parameters in these patients. Methods We studied 57 patients with stable coronary artery disease undergoing one course of external counterpulsation therapy. The average age of the patients was 63.07 ± 7.44 years (there were 43 (75.4%) male and 14 (24.6%) women). All patients divided into two groups: patients with diastolic dysfunction of the left ventricle (E/e" ratio > 14, total 15 patients, main group) and control group (E/e"< =14, total 42 patients). The mean age of the patients included in the main and control groups was 64.20 ± 5.93 and 62.67 ± 7.93 years (p = 0.36). All patients treated with one course of ECP (EECP) treatment (33,26 ± 3,60 and 32,85 ± 4,56 sessions, p = 0,38). Results from echocardiographic examinations after the treatment in these groups were compared. Echocardiographic assessment included evaluation of the chamber size, chamber volume, ejection fraction of the left ventricle (LV) by 2D and Doppler measurements. Results Echocardiographic parameters for main and control groups before treatment: the diastolic diameter of the LV (cm): 5,65 ± 0,97 and 5,20 ± 0,62 (p = 0,0913); the end-diastolic volume of the LV (ml): 93.53 ± 28.38 and 75.45 ± 25.13 (p = 0.0163); LV stroke volume (ml): 48,57 ± 11,47 and 43,02 ± 10,64 (p = 0,1471); LV ejection fraction (%): 52.83 ± 10.12 and 59.11 ± 9.53 (p = 0.0340); the volume of the left atrium (ml): 73.25 ± 22.79 and 57.86 ± 20.60 (p = 0.0229); tissue Doppler velocity of the mitral annulus (e ", cm/s): 5,89 ± 1,18 and 7,43 ± 1,50 (p = 0,0006); E/e" ratio: 18,85 ± 3,40 and 9,69 ± 1,95 (p < 0,0001). Echocardiographic parameters for the main and control groups after treatment: the diastolic diameter of the LV (cm): 5.53 ± 0.85 and 5.15 ± 0.57 (p = 0.1879); the end diastolic volume of the LV (ml): 92.91 ± 31.29 and 75.15 ± 22.78 (p = 0.0536); LV stroke volume (ml): 50,77 ± 11,49 and 47,01 ± 11,24 (p = 0,2612); LV ejection fraction (%): 56.81 ± 10.50 and 64.06 ± 7.67 (p = 0.0088); the volume of the left atrium (ml): 60.84 ± 16.20 and 55.77 ± 17.53 (p = 0.2388); tissue Doppler velocity of the mitral annulus (e", cm/s): 6,15 ± 1,11 and 7,73 ± 1,90 (p = 0,0037); E/e" ratio: 15.97 ± 5.39 and 10.08 ± 2.81 (p < 0.0001). Statistically significant changes between two groups noted for the left atrium volume: decrease in 12,41 ± 16,33 ml and 2,09 ± 13,72 ml (p = 0,0124) in both groups, and for E/e" ratio: decrease in -2,87 ± 3,94 in the main group and increase in 0,39 ± 2,12 in the control group (p = 0,0003). Conclusion ECP treatment was associated with a decrease in the left atrium volume and E/e’ ratio in patients with diastolic dysfunction of the left ventricle.

Enhanced external counterpulsation: A new method to alleviate contrast-induced acute kidney injury

BackgroundContrast-induced acute kidney injury (CI-AKI) is a common complication after exposure to contrast media. Renal ischaemia occurs in the initial stage of CI-AKI, however, there are very few effective measures to improve renal perfusion. MethodsA total of 114 patients with an estimated glomerular filtration rate (eGFR) of 60–89 ml/min/1.73m2 were randomly assigned to two groups: enhanced external counterpulsation (EECP) group (N = 57) and control group (N = 57). Two hours after contrast exposure, EECP group received EECP treatment for 1 h while no intervention was performed control group. The primary outcome was the incidence of serum cystatin C concentration to 10% above the baseline concentration at 24 h after contrast administration. The secondary outcomes were the incidence of CI-AKI (defined as an increase in serum creatinine concentration to ≥0.5 mg/dl or by 25% compare to the baseline after contrast exposure), contrast clearance and adverse clinical events. ResultsThe primary outcome was observed in 26 patients (6 EECP and 20 control; 11% vs. 35%; P = 0.002). CI-AKI occurred in four patients (0 EECP and 4 control; 0% vs. 7%; P = 0.042). The clearance rate of iopromide in the initial 3 h was significantly different between EECP and control group (59.92 ± 8.84 vs 46.80 ± 9.26 ml/min/1.73 m2; P < 0.001). No adverse clinical events were observed in this study. ConclusionsThis study demonstrates that EECP increases the contrast clearance and may have an effect in reducing the risk of CI-AKI.The study has been registered in Chinese Clinical Trial Registry (ChiCTR 2,000,039,190).

The detection efficiency study of NaI(Tl) scintillation detector with the different numbers of SiPMs

SiPMs are generally coupled into whole columns in gamma energy spectrum measurement, but the relationship between the distribution of whole SiPM columns and the energy resolution of the measured energy spectra is rarely reported. In this work, ∅ 3 × 3 inch NaI scintillator is placed on an 8 × 8 SiPM array, and the energy resolution of the 137Cs peak at 662 keV corresponding to the γ-ray is selected as a reference. Each SiPM is switched to explore the influence of the number of SiPM arrays, distribution position, and reflective layer on the energy resolution of SiPMs. Results show that without coupling, the energy resolution is greatly improved when the number of SiPMs ranges from 4 to 32. However, after 32 slices (the area covered by SiPMs relative to the scintillator reaches 25.9%), the improvement in energy resolution and total pulse count is not obvious. In addition, the position of SiPMs relative to the scintillator does not exert much impact on the energy resolution. Results also indicate that by adding a reflective film (ESR), the energy resolution of the tested group increases by 10.38% on average. This work can provide a reference for the design and application of miniaturized SiPM gamma spectrometers.

A Systematic Review on the Economic Evaluations Evidence of Enhanced External Counter-Pulsation (EECP) for Managing Chronic Stable Angina.

Background: Chronic Stable Angina (CSA) does not respond to clinical interventions always. Therefore, enhanced external counter pulsation (EECP) has been approved by the Food and Administration Drug (FDA) as an effective technology. This study aimed to synthesize evidence on the economic evaluation of EECP in managing CSA through a systematic approach. Methods: In this systematic review study, PubMed/Medline, Cochrane Library, Web of Sciences, Scopus, National Institute for Health Research Journals Library, and the University of York Centre for Review and Dissemination (CRD) were searched. The targeted population was people who suffered from CSA, and the main therapeutic intervention was EECP. The comparators were not limited to any particular ones. Outcomes were changes in the Canadian Cardiovascular Society grading of angina pectoris, quality of life, and any other investigated relevant outcomes in the retrieved studies. The quality of studies was assessed through Philips et al and Joanna Briggs Institute Critical Appraisal tools. We synthesized data through a narrative approach. Results: We retrieved 7821 studies; among which 3 studies were included in the final phase. Two studies were systematic reviews and the Markov model economic evaluation. Another study was a partial economic evaluation. Conclusion: All studies only considered direct costs. EECP is a cost-effective technology in managing CSA, however, the sensitivity analysis of the studies showed the cost-effectiveness ratio is varied considerably and further studies are needed to extrapolate its economic value.

Enhanced external counterpulsation for management of symptoms associated with long COVID

Study objectiveEnhanced external counterpulsation (EECP) as a possible therapy for Long COVID. DesignRetrospective analysis of a contemporary, consecutive patient cohort. Setting7 outpatient treatment centers. ParticipantsLong COVID patients. Intervention15–35 EECP treatments. Main outcome measuresThe change from baseline in 1) Patient Reported Outcome Measurement Information System (PROMIS) Fatigue; 2) Seattle Angina Questionnaire (SAQ); 3) Duke Activity Status Index (DASI); 4) 6-Minute Walk Test (6MWT); 5) Canadian Cardiovascular Society (CCS) Angina Grade; 6) Rose Dyspnea Scale (RDS); and 7) Patient Health Questionnaire (PHQ-9). ResultsCompared to baseline, the PROMIS Fatigue, SAQ, DASI, and 6MWT improved by 4.63 ± 3.42 (p < 0.001), 21.44 ± 16.54 (p < 0.001), 18.08 ± 13.82 (p < 0.001), and 200.00 ± 180.14 (p = 0.002), respectively. CCS and RDS improved in 63% and 44% of patients, respectively. All patients unable to work prior to EECP were able to return post-therapy. Conclusions and relevanceEECP significantly improved validated fatigue and cardiovascular-related markers in patients with Long COVID.

A Lightweight Sampling Time Error Correction Technique for Micro Phasor Measurement Units

In this paper, we deal with enhancing the accuracy of the sampling instant of Micro Phasor Measurement Units (&#x03BC;PMUs) used in distribution grids. The pulse per second (PPS) signal of the GPS synchronizes the start of each second of all &#x03BC;PMUs in the grid. The internal clock of each &#x03BC;PMUs then takes over and determines the sampling instants till the next PPS. Due to the inaccuracy and drift of the clock and the unavoidably needed fractional count of the clock pulses, accumulation of error leads to excessive phase error. A lightweight algorithm is proposed for the correction of the sampling period. The algorithm fine tunes the timer count used to determine the sampling instant. As the proposed algorithm aims at correcting the sampling instant, it can be applied by any other platform, but it needs an accurate time reference like that of the 1PPS (1 pulse per second) of the GPS. The performance evaluation shows that, the maximum phase error is lower than the accepted phase error by about two orders of magnitude. The theoretical results are confirmed by implementing the algorithm on a prototype &#x03BC;PMU.

A Personalized 0D-1D Modeling Approach of Cardiovascular System for the Hemodynamics Simulation of Enhanced External Counterpulsation

A Personalized 0D-1D Modeling Approach of Cardiovascular System for the Hemodynamics Simulation of Enhanced External Counterpulsation

Intra-aortic Balloon Pump May Attenuate Adverse Hemodynamic Effects of Negative Intrathoracic Pressure in Cardiogenic Shock

High negative intrathoracic pressure (NIP), as occurs during obstructive sleep apnea or hiccups, results in adverse hemodynamic consequences, specifically a decrease in left ventricle (LV) performance. These untoward effects can potentially be catastrophic in the case of an already compromised LV in cardiogenic shock. The interplay of intra-aortic balloon pump counter pulsation during abrupt high NIP in cardiogenic shock is described.

Highly sensitive broadband photomultiplication type all-polymer photodetectors and their applications in optical pulse counting

Broadband photomultiplication type all-polymer photodetectors with the structure of ITO/PFN-Br/PBDB-T : PYF-T-o (3 : 100)/LiF/Au achieve EQEs of 18 000% at 360 nm and 9000% at 850 nm under 4 V, which are applied in an optical pulse counting circuit.

Vital Sign Detection via Angular and Range Measurements With mmWave MIMO Radars: Algorithms and Trials

Vital signs such as respiration rate and pulse (heart rhythm) rates are very useful in determining health problems and managing well-being. Heart rate measurement techniques have evolved from counting pulses to contact-based approaches such as electrocardiography (ECG) and photoplethysmography (PPG). The current availability and proliferation of low-cost and easily integrable millimeter wave (mmWave) radar sensors make contact-free simultaneous detection of weak vital sign signals highly promising. However, radar echoes reflected from the mechanical behavior of the heart (i.e. heartbeat) are complex and mixed with other (usually stronger) mechanical signals (respiration, body movements, etc.). Such echoes, as captured by radar sensors, comprise a range of Doppler frequencies with varying densities. These frequencies can be directly related to the respiratory and heart rate patterns. Conventional spectral-based approaches adopted directly from radar signal processing do not always yield an accurate estimations of these frequencies. For example, the harmonics of the respiration signal, intermodulation, and cross-product terms complicate the robust detection of heart rate signals. In this study, we show that spatially scanning a human participant using digital beamforming methods provides a more reliable estimation technique for heart rate detection. Prior studies using radar sensors that can filter participants in the range use a range selection strategy based on either the maximum return signal or the highest variance. We developed a strategy to incorporate multiple range and angular bins to reduce the probability of erroneous heart rate estimation. The algorithm, tested on multiple participants, provides an accurate heart rate estimation compared to existing methods.

Effects of Enhanced External Counterpulsation With Different Sequential Levels on Lower Extremity Hemodynamics.

Objective: This study aimed to investigate acute hemodynamics of lower extremities during enhanced external counterpulsation with a three-level sequence at the hips, thighs, and calves (EECP-3), two-level sequence at the hips and thighs (EECP-2), and single leg three-level sequence (EECP-1).Methods: Twenty healthy volunteers were recruited in this study to receive a 45-min EECP intervention. Blood flow spectrums in the anterior tibial artery, posterior tibial artery, and dorsalis pedis artery were imaged by Color Doppler ultrasound. Mean flow rate (FR), area, pulsatility index (PI), peak systolic velocity (PSV), end-diastolic velocity (EDV), mean flow velocity (MV), and systolic maximum acceleration (CCAs) were sequentially measured and calculated at baseline during EECP-3, EECP-1, and EECP-2.Results: During EECP-3, PI, PSV, and MV in the anterior tibial artery were significantly higher, while EDV was markedly lower during EECP-1, EECP-2, and baseline (all P < 0.05). Additionally, ACCs were significantly elevated during EECP-3 compared with baseline. Moreover, FR in the anterior tibial artery was significantly increased during EECP-3 compared with baseline (P = 0.048). During EECP-2, PI and MV in the dorsalis pedis artery were significantly higher and lower than those at baseline, (both P < 0.05). In addition, FR was markedly reduced during EECP-2 compared with baseline (P = 0.028). During EECP-1, the area was significantly lower, while EDV was markedly higher in the posterior tibial artery than during EECP-1, EECP-2, and baseline (all P < 0.05). Meanwhile, FR of the posterior tibial artery was significantly reduced compared with baseline (P = 0.014).Conclusion: Enhanced external counterpulsation with three-level sequence (EECP-3), EECP-2, and EECP-1 induced different hemodynamic responses in the anterior tibial artery, dorsalis pedis artery, and posterior tibial artery, respectively. EECP-3 acutely improved the blood flow, blood flow velocity, and ACCs of the anterior tibial artery. In addition, EECP-1 and EECP-2 significantly increased the blood flow velocity and peripheral resistance of the inferior knee artery, whereas they markedly reduced blood flow in the posterior tibial artery.

Frequency-Domain Characteristics Response to Passive Exercise in Patients With Coronary Artery Disease.

Purpose: The enhanced external counterpulsation (EECP), a kind of passive exercise, is a novel non-invasive therapy used to improve peripheral perfusion in patients with coronary artery disease (CAD). However, whether frequency-domain characteristics of peripheral hemodynamics may benefit from passive exercise needs to be verified.Methods: We recruited 21 patients with CAD and 21 healthy controls in this study. Ultrasonic blood flow velocity spectrum in left carotid (LC) and right carotid (RC) common arteries, and right brachial (RB) and right femoral (RF) arteries was monitored using an ultrasonic Doppler. Frequency-domain characteristics before, during, and after passive exercise were extracted from ultrasonic spectrum images. The first and second peak amplitudes/frequencies (y1, y2, x1, x2) and power spectral energy ratio (PSER) in the 0–2.05 Hz/0.87 Hz (p5, p6) were calculated by fast Fourier transform and power spectrum density analysis.Results: For the amplitude and frequency characteristics of the spectrum, y1 in the LC of patients with CAD was significantly decreased during exercise (p = 0.036), whereas, y2 was significantly decreased immediately after passive exercise (p = 0.038). Besides those, y1 only in the RC and RB of controls was significantly decreased during exercise. Immediately after exercise, y2 in the LC of control was significantly lower than at the baseline (p = 0.014). For the energy ratio characteristics of the spectrum, there was an opposite response in the two groups that p6 was significantly reduced and elevated in the LC of controls and in the RB of patients with CAD during exercise (both p < 0.05).Conclusions: Passive exercise reduces amplitude and frequency characteristics of carotid arteries, while there was an opposite response of energy ratio characteristics in the LC and RB arteries to passive exercise between CAD patients and controls. Additionally, energy ratio characteristics of spectrum in the brachial artery were markedly elevated in CAD patients during passive exercise. Moreover, passive exercise only reduces amplitude characteristics of LC artery in the control group.

Baseline neuroimaging characteristics in the randomized pivotal study of renew NCP‐5 for the treatment of mild cognitive impairment (MCI) due to Alzheimer's disease or mild dementia of the Alzheimer's type

AbstractBackgroundRenew NCP‐5 is an FDA‐cleared, external counterpulsation (ECP) device used clinically to improve coronary and peripheral vascular hemodynamics by sequential compression and decompression of vascular beds in synchrony with the cardiac cycle. NCP‐5 treatment may have a beneficial effect on disorders of blood flow including mild cognitive impairment (MCI) and Alzheimer’s disease (AD). We describe here the baseline neuroimaging characteristics of the participants from a randomized pivotal study of Renew NCP‐5 for the treatment of MCI due to AD or mild dementia of the Alzheimer's type.MethodNeuroimaging was conducted across ten sites in the United States for safety screening, baseline imaging assessment including disease severity, and for acquisition of exploratory neuroimaging markers of treatment modification. Imaging protocols were based on the cross‐platform protocols developed for the Alzheimer's Disease Neuroimaging Initiative (ADNI3). Participant characterization and exploratory outcome neuroimaging measures included T1‐weighted hippocampal volume and arterial spin labeling‐based measures of cerebral blood flow (CBF).ResultBaseline structural data were acquired in 97 participants in the NCP‐5 group, and 89 participants in the active sham group. ASL data were available on a subset of scanners and acquired in 60 participants in the NCP‐5 group and 48 participants in the active sham group. Baseline neuroimaging assessment revealed expected variation with age and disease severity in the total cohort. A difference in baseline hippocampal volume and CBF was detected between the randomized groups with the NCP‐5 group having reduced measures (reduced hippocampal volume and reduced CBF) compared to the active sham group. These effects were apparent when splitting the treatment groups by disease severity and cardiovascular risk.ConclusionWe present here the baseline characteristics for the participant cohort for the randomized pivotal study of Renew NCP‐5 for the treatment of MCI due to AD or mild dementia of the Alzheimer's type. Imaging measures were in accord with expected directional effects for age and for disease. There was an unexpected difference between the NCP‐5 treatment and active sham group at baseline with the NCP‐5 group having greater neurodegeneration. Longitudinal imaging data are being examined in ongoing work.

Antibacterial and anticandidal effects of atmospheric-pressure, non-thermal, nitrogen- and argon-plasma pulses.

Atmospheric-pressure, non-thermal plasma destroys microorganisms by directly reacting with hydrocarbon molecules in the cell wall and/or by damaging the cytoplasmic membrane, proteins, and DNA with charged particles and reactive species. The aim of our study was to evaluate the antibacterial and anticandidal effects of atmospheric-pressure, non-thermal, nitrogen- and argon-plasma pulses on various pathogen preparations. The resultant antibacterial and anticandidal effects were assessed by evaluating percent and log reduction values for pathogen colonies. Nitrogen-plasma pulses emitted at an energy of 1.5J and argon-plasma pulses generated at 0.5J elicited remarkable antibacterial effects on Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA) and anticandidal effects on Candida albicans. Nitrogen-plasma pulses at a pulse count of five elicited remarkable antibacterial effects on Cutibacterium acnes at the energy settings of 1.75, 2.5, and 3J, but not at 1J. Meanwhile, argon-plasma pulses showed antibacterial effects on C. acnes at an energy of 0.5 and 0.65 J. Nitrogen- or argon-plasma pulses exert antibacterial and anticandidal effects on bacterial and fungal pathogens.

Detection Probability Analysis of True Random Coding Photon Counting Lidar

With the wide application of lidar in the future, the problem of crosstalk between lidars will become more serious. True random coding photon counting lidar with high anti-crosstalk ability will play an important role in solving this problem. In this paper, based on the working principle of Gm-APD, the detection probability theoretical model of true random coding photon counting lidar is built, and the impact of jitter on detection probability is considered for the first time. The influence of mean echo photon number, mean pulse count density, sequence length and pulse width on detection probability is analyzed. Monte Carlo simulation and experimental results are highly consistent with the theoretical model, which proves the correctness of the detection probability theoretical model. This theoretical model provides an effective means to evaluate the system performance.

Safety and effectiveness of enhanced external counterpulsation (EECP) in refractory angina patients: A systematic reviews and meta-analysis.

Enhanced external counterpulsation (EECP) is believed to be a non-invasive treatment for coronary artery disease and angina. The aim of this study was to determine the safety and effectiveness of EECP in refractory angina patients through a systematic reviews and meta-analysis. We conducted a comprehensive search of the literature published on PubMed, Cochrane library, Scopus, ScienceDirect, Trip Database and Google Scholar databases using appropriate keywords and specific strategy with no time limit. Having selected and screened the studies based on the defined inclusion and exclusion criteria and evaluating their quality based on the Cochrane checklist. For the meta-analysis,the Mantel-Haenszel method or the generic Inverse Variance was used. Analyses were done with Review Manager 5.2 software. A number of 299 studies were initially reviewed and finally, seventeen studies were included in the meta-analysis based on the inclusion and exclusion criteria. Also, thirteen outcomes were analyzed and the results of meta-analysis in twelve outcomes including (Systolic Blood Pressure (7 studies), Diastolic Blood Pressure (7 studies), Pulse Pressure (4 studies), Mean Arterial Pressures (4 studies), Heart Rate (6 studies), Angina episodes (7 studies), Walking distance (2 studies),Canadian Cardiovascular Society classification (6 studies), Flow-Mediated Dilation (3 studies), Daily Nitrate Usage (4 studies), Exercise Treadmill Test-Time (2 studies), ST-segment depression (2 studies)demonstrated a significant clinical advantage in the EECP treatment effectiveness in patients with angina. No significant difference was observed regarding EECP usefulness (P = 0.18) in the outcome of brachial artery diameter (2 studies). Based on the meta-analysis, the results indicate the safety and effectiveness of EECP in patients with angina pectoris and indicate the usefulness of this treatment in these patients. In general, the authors believe that the general conclusion in this regard requires some studies with a large sample size and a control group assignment.

Model-based evaluation of local hemodynamic effects of enhanced external counterpulsation

Background and ObjectivesThe treatment benefits of enhanced external counterpulsation (EECP) heavily depends on hemodynamics. Global hemodynamics of EECP can cause blood flow redistribution in the circulatory system whereas local hemodynamic effects act on vascular endothelial cells (VECs). Local hemodynamic effects of EECP on VECs are important in the treatment of atherosclerosis, but currently cannot be not evaluated. Herein we aim to establish evaluation models of local hemodynamic effects based on the global hemodynamic indicators. MethodsWe established 0D/3D geometric multi-scale hemodynamic models of the coronary and cerebral artery of two healthy individuals to calculate the global hemodynamic indicators and the local hemodynamic effects. Clinical EECP trials were performed to verify the accuracy of the multi-scale hemodynamic model. The global hemodynamic indicators included diastolic blood pressure/systolic blood pressure (Q = D/S), mean arterial pressure (MAP), internal carotid artery flow (ICAF) and cerebral blood flow (CBF), whereas local hemodynamic effects focused on time-averaged wall shear stress (TAWSS). The correlation between these indicators was analyzed via Pearson correlation coefficient. Significantly related indicators were selected for curve-fitting to establish evaluation models of the coronary and cerebral artery. Moreover, clinical data of a coronary heart disease patient and a cerebral ischemic stroke patient were collected to verify the effectiveness of the application of the established evaluation models to real patients. ResultsFor coronary artery, TAWSS was correlated to Q = D/S and ICAF (P < 0.05), whereas for cerebral artery, TAWSS was correlated to MAP and CBF (P < 0.05). The mean square error (MSE) between the evaluated values using evaluation model and the calculated values using 0D/3D model of TAWSS of the coronary and cerebral artery were 5.4% and 1.0%, respectively. The MSE of evaluation model applied to real patients was greater than that applied to healthy individuals, but within an acceptable range. ConclusionsThe presented error demonstrated validity and accuracy of the evaluation models in clinical patients. Based on the evaluation models, global hemodynamic indicators could be used to evaluate the local hemodynamic effects under the current counterpulsation mode. With TAWSS range of 4–7 Pa as the target range, EECP strategies can further be optimized.

Abstract 13341: Enhanced External Counterpulsation Attenuates Coronary Microcirculation Dysfunction in Coronary Artery Disease With Diabetes: Primary Results of EECP-CMD Study

Introduction: Coronary microcirculation dysfunction (CMD) is recognized as a pivotal pathophysiological change of coronary artery disease (CAD) with diabetes, however, there is little evidence for CMD medication treatment. Though enhanced external counterpulsation (EECP), a non-invasive therapy to increase shear stress of coronary flow, has been proved to release angina and restore endothelial capacities, whether EECP could attenuate CMD remains unknown. Hypothesis: EECP could attenuate CMD in patients of CAD with diabetes. Methods: This is a single center, prospective, randomized, single blind, control clinical trial (ChiCTR1800019060). Forty-eight patients [age: (57.7±8.5) yrs, 30 males] diagnosed with CAD and diabetes were enrolled during March 2019 and October 2020 in the Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, China. The main exclusion criteria are as follows: type 1 diabetes or diabetes history≤3 years; ≥ 70 years old; acute coronary syndrome; chronic total occlusion lesions and contraindications for EECP. All accepted coronary angiography and index of microcirculation resistance (IMR) test with pressure wire, then were randomized to EECP (n=24) or control (n=24) group. All followed standard medication therapy as guidelines recommended, EECP group took 35 times of EECP (60 minutes per time, 5 times a week and 7 weeks for whole procedure) after IMR test. Another IMR test would be done at the end of 12-week follow-up, the occurrence of angina and the metabolic parameters, FMD, PWV, CPET and TTE would also be evaluated. Results: The baseline IMR displayed no significant difference in both groups [EECP: (26.56±3.70) vs. Control: (26.91±4.22), P =0.74], while IMR markedly decreased in the EECP group than control at the end of follow-up [(24.02±3.15) vs. (26.78±4.63), P =0.02]. After multivariate linear regression analysis, FMD and PWV were found to independently correlated with IMR change [FMD: (β=0.45, P =0.014); PWV: (β=-0.27, P =0.038)]. Apart from above, EECP reduced angina occurrence and improved exercise tolerance, early diastolic function of left ventricular. Conclusion: EECP attenuates CMD in CAD with diabetes through coronary microcirculation resistance decrease.

Abstract 11515: Noninvasive Quantitation of Coronary Collateral Flow Capacity in Patients with Chronic Total Occlusion Treated with External Counter Pulsation: Dobutamine Compared with Vasodilator Stress Pet Identifies Collaterogenesis

Introduction: FDA approved external counterpulsation (ECP) improves coronary collateral flow index measured invasively, using intracoronary wedge pressure beyond a severe stenosis. However, there is presently no noninvasive method to measure coronary collateral flow capacity (CCFC), in patients with total coronary occlusion (CTO). Hypothesis: CCFC can be measured noninvasively by comparing the improvement in flow in the ischemic bed beyond CTO, using dobutamine stress (DBT), which supports supply side pressure, compared with vasodilator stress (DIP), which lowers supply side pressure, causing coronary steal. Methods: Seven patients with CTO were treated with 35 sessions of ECP, and studied with both DIP and DOB stress PET myocardial perfusion imaging. Coronary flow capacity (CFC), which integrates absolute rest and stress flow with coronary flow reserve on a per pixel basis, was measured objectively with FDA approved HeartSee software. Results: As shown in the Table, all patients demonstrated a decrease in the size of the ischemic zone at risk, defined as moderate or severely reduced CFC, when CFC with DIP was compared with DOB: 28% LV mass vs. 5%; p &amp;lt 0.01. Five of 7 patients also demonstrated significant improvement in global CFC by Kolmogorov-Smirnoff analysis. Absolute stress flow into the ischemic zone improved significantly in all ECP treated patients during demand ischemia compared with vasodilator stress (1.9 vs. 1 ml/min/g; p &amp;lt 0.01). One of the two patients who did not improve global CFC, despite ECP treatment, underwent coronary arteriography demonstrating a new flow limiting stenosis in the supply side vessel, which was successfully stented. Conclusion: ECP treatment is associated with improved coronary collateralization in patients with CTO, which can be identified noninvasively with quantitative PET myocardial perfusion imaging.