Enhanced external counterpulsation treatment improves multi-organ hemodynamics for postoperative liver transplantation patient. A case report.

INTRODUCTION: Post liver transplantation (LT) patients endure high morbidity rate of multi-organ ischemic symptoms following reperfusion. We hypothesize that enhanced external counterpulsation (EECP) as a typical non-invasive assisted circulation procedure, which can efficiently inhibit the relative ischemic symptoms via the systemic improvement of hemodynamics. CASE PRESENTATION: A 51-year-old male patient, 76 kg, 172 cm, received orthotopic LT surgery for viral hepatitis B induced acute-on-chronic liver failure hepatic failure. His medical records revealed ischemic symptoms in multi-organ at the time of hospital discharge, including headache, refractory insomnia, abdominal paralysis, and lower limb pain. The EECP treatment was introduced for assisted rehabilitation and to improve the postoperative quality of life. Doppler Ultrasound examination showed significant augmentation of blood flow volume in the carotid arteries, the hepatic artery, the portal vein and the femoral artery during EECP intervention. A standard 35-hour EECP treatment led to significant improvement in quality of life, e.g. sleep quality and walking ability. CONCLUSION: We report a case of multi-organ ischemic symptoms in a post LT patient. EECP treatment can significantly improve the quality of life via the systematic promotion of hemodynamics.

Hemodynamics of ventricular-arterial coupling under enhanced external counterpulsation: An optimized dual-source lumped parameter model.

BACKGROUND AND OBJECTIVE: Enhanced external counterpulsation (EECP) is a mechanically assisted circulation technique widely used in the rehabilitation and management of ischemic cardiovascular diseases. It contributes to cardiovascular functions by regulating the afterload of ventricle to improve hemodynamic effects, including increased diastolic blood pressure at aortic root, increased cardiac output and enhanced blood perfusion to multiple organs including coronary circulation. However, the effects of EECP on the coupling of the ventricle and the arterial system, termed ventricular-arterial coupling (VAC), remain elusive. We aimed to investigate the acute effect of EECP on the dynamic interaction between the left ventricle and its afterload of the arterial system from the perspective of ventricular output work. METHODS: A neural network assisted optimization algorithm was proposed to identify the ordinary differential equation (ODE) relation between aortic root blood pressure and flow rate. Based on the optimized order of ODE, a lumped parameter model (LPM) under EECP was developed taking into consideration of the simultaneous action of cardiac and EECP pressure sources. The ventricular output work, in terms of aortic pressure and flow rate cooperated with the LPM, was used to characterize the VAC of ventricle and its afterload. The VAC subjected to the principle of minimal ventricular output work was validated by solving the Euler-Poisson equation of cost function, ultimately determining the waveforms of aortic pressure and flow rate. RESULTS: A third-order ODE can precisely describe the hemodynamic relationship between aortic pressure and flow rate. An optimized dual-source LPM with three energy-storage elements has been constructed, showing the potential in probing VAC under EECP. The LPM simulation results demonstrated that the VAC in terms of aortic pressure and flow rate yielded to the minimal ventricular output work under different EECP pressures. CONCLUSIONS: The ventricular-arterial coupling under EECP is subjected to the minimal ventricular output work, which can serve as a criterion for determining aortic pressure and flow rate. This study provides insight for the understanding of VAC and has the potential in characterizing the performance of the ventricular and arterial system under EECP.

A numerical study on the siphonic effect of enhanced external counterpulsation at lower extremities with a coupled 0D-1D closed-loop personalized hemodynamics model.

Enhanced external counterpulsation (EECP) is a treatment and rehabilitation approach for ischemic diseases, including coronary artery disease. Its therapeutic benefits are primarily attributed to the improved blood circulation achieved through sequential mechanical compression of the lower extremities. However, despite the crucial role that hemodynamic effects in the lower extremity arteries play in determining the effectiveness of EECP treatment, most studies have focused on the diastole phase and ignored the systolic phase. In the present study, a novel siphon model (SM) was developed to investigate the interdependence of several hemodynamic parameters, including pulse wave velocity, femoral flow rate, the operation pressure of cuffs, and the mean blood flow changes in the femoral artery throughout EECP therapy. To verify the accuracy of the SM, we coupled the predicted afterload in the lower extremity arteries during deflation using SM with the 0D-1D patient-specific model. Finally, the simulation results were compared with clinical measurements obtained during EECP therapy to verify the applicability and accuracy of the SM, as well as the coupling method. The precision and reliability of the previously developed personalized approach were further affirmed in this study. The average waveform similarity coefficient between the simulation results and the clinical measurements during the rest state exceeded 90%. This work has the potential to enhance our understanding of the hemodynamic mechanisms involved in EECP treatment and provide valuable insights for clinical decision-making.

A real-time patient-specific treatment strategy for enhanced external counterpulsation.

Diastolic/systolic blood pressure ratio (D/S) ≥ 1.2 is the gold standard of enhanced external counterpulsation (EECP) treatment, but it does not show a clear clinical correspondence with the configuration of the EECP mode. As such, a single target results in different treatment effects in different individuals. The local haemodynamic effect (wall shear stress, WSS) of EECP on vascular endothelial cells is conducive to promote the growth of collateral circulation vessels and restore the blood supply distal to the stenosis lesion. Considering the haemodynamic effects of WSS on human arteries, this study developed a real-time patient-specific treatment strategy of EECP for patients with cardio-cerebrovascular diseases. Based on patient-specific haemodynamic data from 113 individuals, an optimization algorithm was developed to achieve the individualization of a 0D lumped-parameter model of the human circulatory system, thereby simulating the patient-specific global haemodynamic effects. 0D/3D coupled cardio-cerebrovascular models of two subjects were established to simulate the local WSS. We then established statistical models to evaluate clinically unmeasurable WSS based on measurable global haemodynamic indicators. With the aim of attaining appropriate area- and time-averaged WSS (ATAWSS, 4-7 Pa), as evaluated by global haemodynamic indicators, a closed-loop feedback tuning method was developed to provide patient-specific EECP treatment strategies. Results showed that for clinical data collected from 113 individuals, the individualized 0D model can accurately simulate patient-specific global haemodynamic effects (average error <5%). Based on two subjects, the statistical models can be used to evaluate local ATAWSS (error <6%) for coronary arteries and for cerebral arteries. An EECP mode planned by the patient-specific treatment strategy can promote an appropriate ATAWSS within a 16 s calculation time. The real-time patient-specific treatment strategy of EECP is expected to improve the long-term outcome for each patient and have potential clinical significance.

Influence of enhanced external counterpulsation on endothelial function: a meta-analysis of randomized controlled trials.

OBJECTIVES: Enhanced external counterpulsation (EECP) is an effective and noninvasive treatment for patients with refractory angina and chronic heart failure. However, previous studies evaluating the influence of EECP on endothelial function showed inconsistent results. This systematic review and meta-analysis was conducted to evaluate the effects of EECP on endothelial function measured by brachial artery flow-mediated dilation (FMD). DESIGN: PubMed, Embase, Cochrane Library, CNKI, and Wanfang databases were searched for randomized controlled trials comparing the influence of EECP versus usual care on FMD in adult population. A random-effects model incorporating the potential influence of heterogeneity was used to pool the results. RESULTS: Nineteen studies with 1647 patients were included in the meta-analysis. Compared with usual care or conventional therapy, additional treatment with EECP for 3-7 weeks was associated with a significantly improved FMD (mean difference [MD]: 1.96%, 95% confidence interval [CI]: 1.57-2.36, p < 0.001, I2 = 52%). Subgroup analysis showed consistent results in patients with coronary artery disease and in patients with other diseases (p for subgroup difference = 0.21). Results of meta-regression analysis showed that the mean baseline FMD level was positively correlated with the influence of EECP on FMD (coefficient = 0.42, p < 0.001). Results of subgroup analysis suggested that the increment of FMD following EECP was larger in patients with baseline FMD ≥ 5% (MD: 2.69, 95% CI: 2.27-3.10, p < 0.001; I2 = 15%) compared to those with baseline FMD < 5% (MD: 1.49, 95% CI: 1.13-1.85, p < 0.001; I2 = 0%; p for subgroup difference < 0.001). CONCLUSIONS: EECP may be effective in improving endothelial function measured by FMD.

Enhanced external counterpulsation treatment regulates blood flow and wall shear stress metrics in femoral artery: An in vivo study in healthy subjects.

As a non-invasive assisted circulation therapy, enhanced external counterpulsation (EECP) has demonstrated potential in treatment of lower-extremity arterial disease (LEAD). However, the underlying hemodynamic mechanism remains unclear. This study aimed to conduct the first prospective investigation of the EECP-induced responses of blood flow behavior and wall shear stress (WSS) metrics in the femoral artery. Twelve healthy male volunteers were enrolled. A Doppler ultrasound-basedapproach was introduced for the in vivo determination of blood flow in the common femoral artery (CFA) and superficial femoral artery (SFA) during EECP intervention, with incremental treatment pressures ranging from 10 to 40 kPa. Three-dimensional subject-specific numerical models were developed in 6 subjects to quantitatively assess variations in WSS-derived hemodynamic metrics in the femoral bifurcation. A mesh-independence analysis was performed. Our results indicated that, compared to the pre-EECP condition, both the antegrade and retrograde blood flow volumes in the CFA and SFA were significantly augmented during EECP intervention, while the heart rate remained constant. The time average shear stress (TAWSS) over the entire femoral bifurcation increased by 32.41%, 121.30%, 178.24%, and 214.81% during EECP with treatment pressures of 10 kPa, 20 kPa, 30 kPa, and 40 kPa, respectively. The mean relative resident time (RRT) decreased by 24.53%, 61.01%, 69.81%, and 77.99%, respectively. The percentage of area with low TAWSS in the femoral artery dropped to nearly zero during EECP with a treatment pressure greater than or equal to 30 kPa. We suggest that EECP is an effective and non-invasive approach for regulating blood flow and WSS in lower extremity arteries.

The Effect of EECP on Ischemic Heart Failure: a Systematic Review.

PURPOSE OF REVIEW: Heart failure is a serious global health problem, and coronary artery disease is one of the main causes. At present, the treatment options for ischemic heart failure (IHF) are limited. This article mainly aims to explore the evidence of enhanced external counterpulsation (EECP) as a non-invasive cardiac rehabilitation method in patients with IHF and to make a preliminary exploration of its mechanisms. RECENT FINDINGS: According to the existing evidence, the standard course of EECP is safe in patients with IHF and can significantly improve the quality of life of these patients. The effect of EECP on systolic function is still unclear, while EECP has a significant improvement effect on cardiac diastolic function. At the same time, this treatment can reduce the re-hospitalization rate and emergency visit rate of patients within 6 months. In terms of mechanisms, in addition to the immediate hemodynamic effect, existing evidence mostly suggests that its improvement of cardiac function may come from its upregulation of shear stress to improve myocardial perfusion. EECP is safe to use in patients with stable ischemic heart failure, and it can improve the performance status of patients and may be beneficial to cardiac function and reduce the short-term re-hospitalization rate.

Treatment strategy of different enhanced external counterpulsation frequencies for coronary heart disease and cerebral ischemic stroke: A hemodynamic numerical simulation study.

BACKGROUND AND OBJECTIVES: Currently, enhanced external counterpulsation (EECP) devices mainly produce one counterpulsation per cardiac cycle. However, the effect of other frequencies of EECP on the hemodynamics of coronary and cerebral arteries is still unclear. It should be investigated whether one counterpulsation per cardiac cycle leads to the optimal therapeutic effect in patients with different clinical indications. Therefore, we measured the effects of different frequencies of EECP on the hemodynamics of coronary and cerebral arteries to determine the optimal counterpulsation frequency for the treatment of coronary heart disease and cerebral ischemic stroke. METHODS: We established 0D/3D geometric multi-scale hemodynamics model of coronary and cerebral arteries in two healthy individuals, and performed clinical trials of EECP to verify the accuracy of the multi-scale hemodynamics model. The pressure amplitude (35 kPa) and pressurization duration (0.6 s) were fixed. The global and local hemodynamics of coronary and cerebral arteries were studied by changing counterpulsation frequency. Three frequency modes, including one counterpulsation in one, two and three cardiac cycles, were applied. Global hemodynamic indicators included diastolic / systolic blood pressure (D/S), mean arterial pressure (MAP), coronary artery flow (CAF), and cerebral blood flow (CBF), whereas local hemodynamic effects included area-time-averaged wall shear stress (ATAWSS) and oscillatory shear index (OSI). The optimal counterpulsation frequency was verified by analyzing the hemodynamic effects of different frequency modes of counterpulsation cycles and full cycles. RESULTS: In the full cycle, CAF, CBF and ATAWSS of coronary and cerebral arteries were the highest when one counterpulsation per cardiac cycle was applied. However, in the counterpulsation cycle, the global and local hemodynamic indicators of coronary and cerebral artery reached the highest when one counterpulsation in one cardiac cycle or two cardiac cycles was applied. CONCLUSIONS: For clinical application, the results of global hemodynamic indicators in the full cycle have more clinical practical significance. Combined with the comprehensive analysis of local hemodynamic indicators, it can be concluded that for coronary heart disease and cerebral ischemic stroke, applying one counterpulsation per cardiac cycle may provide the optimal benefit.

Tolerability safety and effectiveness of enhanced external counterpulsation versus individual shear rate therapy in patients with lower extremity atherosclerotic disease: A prospective pilot clinical trial.

AIMS: We aimed to investigate the tolerability, safety, and effectiveness of enhanced external counterpulsation therapy (EECP) versus individual shear rate therapy (ISRT) in patients with lower extremity atherosclerotic disease (LEAD). METHODS: Eighteen patients (age: 73.1 ± 6 years) underwent EECP and ISRT, each daily over five consecutive days in a cross-over design with a 1 week resting period in between the two regimens. A quality-of-life questionnaire was used to assess the therapy experience. Oxygen saturation (SO2 ), relative hemoglobin amount (rHb) and blood flow (Flow) in the capillary-venous-system (microcirculation) of the skin were monitored continuously during all therapy sessions using the micro-lightguide spectrophotometer, also known as oxygen to see (O2C). The effects of EECP and ISRT on the renal function and skeletal muscles were evaluated using serial blood and urine tests. RESULTS: EECP therapy had to be terminated early before the end of the 5th session in 10 patients (55.6%) because of discomfort. Four patients (22.2%) experienced signs of critical limb ischaemia under EECP. The total score of the quality-of-life questionnaire was significantly higher (= better tolerated) post-ISRT compared with EECP. Microcirculation monitoring revealed that ISRT significantly increased the SO2 , blood flow and rHb during the therapy. All three parameters remained significantly increased in the observation period after ISRT. The serum levels of creatin kinase and myoglobin increased significantly under EECP. CONCLUSIONS: ISRT significantly improves tolerability, safety, and effectiveness over EECP in patients with LEAD.

A personalized 0D-1D model of cardiovascular system for the hemodynamic simulation of enhanced external counterpulsation.

BACKGROUND AND OBJECTIVE: Enhanced external counterpulsation (EECP) is a non-invasive treatment modality capable of treating a variety of ischemic diseases. Currently, no effective methods of predicting the patient-specific hemodynamic effects of EECP are available. In this study, a personalized 0D-1D model of the cardiovascular system was developed for hemodynamic simulation to simulate the changes in blood flow in the EECP state and develop the best treatment protocol for each individual. METHODS: A 0D-1D closed-loop model of the cardiovascular system was developed for hemodynamic simulation, consisting of a 1D wave propagation model for arteries, a 0D model for veins and capillaries, and a one-fiber model for the heart. Additionally, a simulation model coupling EECP with a 1D model was established. Physiological data, including the blood flow in different arteries, were clinically collected from 22 volunteers at rest and in the EECP state. Sensitivity analysis and a simulated annealing algorithm were used to build personalized 0D-1D models using the clinical data in the rest state as optimization objectives. Then, the clinical data on EECP were used to verify the applicability and accuracy of the personalized models. RESULTS: The simulation results and clinical data were found to be in agreement for all 22 subjects, with waveform similarity coefficients (r) exceeding 90% for most arteries at rest and 80% for most arteries during EECP. CONCLUSIONS: The 0D-1D closed-loop model and the optimized method can facilitate personalized modeling of the cardiovascular system using the data in the rest state and effectively predict the hemodynamic changes in the EECP state, which is significant for the numerical simulation of personalized hemodynamics. The model can also potentially be used to make decisions regarding patient-specific treatment.

Enhanced External Counterpulsation Effects on Venous Leg Symptoms.

BACKGROUND: Venous diseases encompass a large spectrum of abnormalities in the venous system with complaints, such as aching and swelling. Enhanced external counterpulsa-tion, proven safe and effective in patients with coronary artery disease and chronic heart failure, is a technique that increases venous return and augments diastolic blood pres-sure. This study assessed the effects of enhanced external counterpulsation on symp-toms of venous disease using the Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms questionnaire. METHODS: This study was designed prospectively for evaluating venous symptoms before and after enhanced external counterpulsation treatment. The study population con-sisted of 30 consecutive patients who were admitted to the cardiology clinic. The Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms ques-tionnaire was applied to assess venous symptoms one day before and after enhanced external counterpulsation treatment. RESULTS: The mean age of the patients was 64.62 ± 9.67 years. After 35 hours of enhanced external counterpulsation, 28 patients (93%) had at least 1 New York Heart Association functional class reduction compared with baseline and 43% of patients had 2 New York Heart Association functional classes improvement. The New York Heart Association class significantly decreased after enhanced external counterpulsation treatment (P<.001). There was a significant improvement in their swelling and night cramps symptoms compared with baseline (P< .001 and P = .05, respectively). Also, The left ventricular ejec-tion fraction significantly increased after the enhanced external counterpulsation treat- ment (P = .02). CONCLUSIONS: The findings obtained in the present study suggested that patients treated with enhanced external counterpulsation showed a significant reduction in swelling and night cramps symptoms. Although the total VEIN score did not change after the enhanced external counterpulsation procedure, improvement in swelling and night cramps under-lines the beneficial effects of enhanced external counterpulsation through the venousvascular territory.

The Effect of Long-Term External Counterpulsation Combined with Exercise Therapy on the Establishment of Collateral Circulation in Patients with Coronary Artery Occlusive Disease.

Objective: By detecting the levels of external counterpulsation combined with exercise therapy on the levels of moesin, angiopoietin-like protein2 (Angptl 2), angiopoietin-like protein (Angptl 3), hypoxia inducible factor-1α (HIF-1α), and RNA-34a (miR-34a) in patients with coronary artery occlusive disease, the effect of external counterpulsation combined with exercise therapy on the establishment of occluded coronary collateral circulation was studied. Methods: A retrospective analysis of 166 patients with coronary heart disease was confirmed by coronary angiography results that at least one coronary artery (anterior descending branch, circumflex branch, and right coronary artery) was completely occluded and was classified into the control group (routine medication) and the treatment group (routine drug therapy plus exercise therapy and external counterpulsation) according to the treatment plan of the patient. The serum levels of moesin, Angptl 2, Angptl 3, and HIF-1α were detected by enzyme-linked immunosorbent assay (ELISA) test. The index of microcirculatory resistance (IMR) and coronary flow reserve (CFR) of the two groups of patients were measured before and after 2 weeks of treatment. The formation of collateral circulation was analyzed according to the Rentrop classification method. Results: After treatment, the IMR levels of the two groups were significantly decreased, and the CFR levels were significantly increased. The decrease of IMR level and the increase of CFR level in the experimental group were better than those in the control group (P < 0.05). There was no significant difference in the positive detection rate of moesin antibody between the two groups, but the OD detection value of the treatment group decreased significantly (P < 0.05). The levels of Angptl 2, Angptl 3, and miR-34a in the treatment group were lower than those in the control group, while the relative expression of HIF-1α was higher than that in the control group. The difference was statistically significant (P < 0.05). External counterpulsation combined with exercise therapy improved the formation rate of collateral circulation (P < 0.05). Conclusions: External counterpulsation combined with exercise therapy can reduce moesin antibody, Angptl 2, Angptl 3, and miR-34a levels increase HIF-1α levels, and promote the establishment of occluded coronary collateral circulation.

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

BACKGROUND: Contrast-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. METHODS: A 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. RESULTS: The 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. CONCLUSIONS: This 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).

Adverse events and their management during enhanced external counterpulsation treatment in patients with refractory angina pectoris: observations from a routine clinical practice.

AIMS: Enhanced external counterpulsation (EECP) is a non-invasive treatment (35 one-hour sessions) for patients with refractory angina pectoris (RAP). To avoid interruption of treatment, more knowledge is needed about potential adverse events (AE) of EECP and their appropriate management. To describe occurrence of AE and clinical actions related to EECP treatment in patients with RAP and compare the distribution of AE between responders and non-responders to treatment. METHODS AND RESULTS: A retrospective study was conducted by reviewing medical records of 119 patients with RAP who had undergone one EECP treatment and a 6-min-walk test pre- and post-treatment. Sociodemographic, medical, and clinical data related to EECP were collected from patients' medical records. An increased walking distance by 10% post-treatment, measured by 6-min-walk test, was considered a responder. The treatment completion rate was high, and the occurrence of AE was low. Adverse events occurred more often in the beginning and gradually decreased towards the end of EECP treatment. The AE were either device related (e.g. muscle pain/soreness) or non-device related (e.g. bradycardia). Medical (e.g. medication adjustments) and/or nursing (e.g. extra padding around the calves, wound dressing) actions were used. The AE distribution did not differ between responders (n = 49, 41.2%) and non-responders. Skin lesion/blister occurred mostly in responders and paraesthesia occurred mostly in non-responders. CONCLUSION: Enhanced external counterpulsation appears to be a safe and well-tolerated treatment option in patients with RAP. However, nurses should be attentive and flexible to meet their patients' needs to prevent AE and early termination of treatment.

The Effect of Enhanced External Counterpulsation on Platelet Aggregation in Patients with Coronary Heart Disease.

BACKGROUND: Resistance to antiplatelet therapy, especially aspirin or clopidogrel, triggers other therapies for patients with coronary heart disease (CHD). Enhanced external counterpulsation (EECP) is a noninvasive, pneumatic technique that provides beneficial effects for patients with CHD. However, the physiological effects of EECP have not been fully studied, and the role of EECP on platelet function remains poorly understood. METHODS: A total of 168 patients with CHD were finally selected from the Second Xiangya Hospital and randomly assigned to either a control group or EECP group. The control group accepted only standard medical treatment, while the EECP group accepted standard medical treatment and EECP treatment. Blood samples were collected from patients at baseline and after EECP, and platelet aggregation was assessed. Changes in platelet aggregation were compared before and after treatment. RESULTS: There was no difference in the basal levels of arachidonic acid (AA) induced platelet maximum aggregation ratio (MAR) between the two groups. The AA-induced platelet MAR was significantly decreased after EECP therapy. The logistic analysis showed that low HDL-C was not favorable for the decrease in platelet aggregation. CONCLUSION: EECP therapy is favorable for lowering platelet aggregation in patients with CHD, especially the AA-induced platelet aggregation ratio.

Still a place for aortic counterpulsation in cardiac surgery and patients with cardiogenic shock?

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2021. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2021 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from https://link.springer.com/bookseries/8901 .

Effects of enhanced external counterpulsation on exercise capacity and quality of life in patients with chronic heart failure: A meta-analysis.

BACKGROUND: This meta-analysis aimed to synthesize randomized controlled trials to evaluate the effects of enhanced external counterpulsation (EECP) on exercise capacity and quality of life in patients with chronic heart failure (CHF). METHODS: Both English and Chinese databases were searched from their inception to June 30, 2020 (PubMed, EMBASE, Cochrane Library, CINAHL (EBSCO), Web of Science for English publications and Chinese Biomedical Database, China National Knowledge Infrastructure, Wanfang Data for Chinese publication). Titles, abstracts, and full-text articles were screened against study inclusion criteria: randomized controlled trials studying EECP intervention for patients with CHF. The meta-analysis was conducted with Revman 5.3 or STATA 16.0. RESULTS: Eight randomized controlled trials were included. EECP induced significant improvement in 6-min walking distance (WMD=84.79 m; 95% CI, 47.64 to 121.95; P < .00001). Moreover, EECP was beneficial for left ventricular ejection fraction (SMD = 0.64; 95% CI,0.29 to 1.00; P = .0004), and N-terminal pro brain natriuretic peptide (SMD = -0.61; 95%CI, -1.20 to -0.01; P = 0.04).However, compared with the control groups, EECP did not significantly reduce the Minnesota Living with Heart Failure Questionnaire scores(WMD, -9.28; 95% CI, -19.30 to 0.75; P = 0.07). CONCLUSIONS: Despite heterogeneity and risk of bias, this meta-analysis confirms that EECP can improve exercise capacity in CHF patients, especially the elderly. However, the evidence that EECP improves the quality of life in patients with CHF is still insufficient. More and larger well-designed randomized controlled trials are still warranted. REGISTRATION INFORMATION: PROSPERO registration no. CRD 42020188848.

The Preference, Effect, and Prognosis of Intra-Aortic Balloon Counterpulsation in Acute Myocardial Infarction Complicated by Cardiogenic Shock Patients: A Retrospective Cohort Study.

BACKGROUNDS: Intra-aortic balloon counterpulsation is increasingly used in acute myocardial infarction complicated by cardiogenic shock. The aim of this study was to explore the preference, effect, and prognosis of intra-aortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock patients. METHODS: Data of acute myocardial infarction complicated by cardiogenic shock patients at the Fourth Medical Center of PLA General Hospital were collected retrospectively. A propensity score was calculated with a logistic regression which contained clinically meaningful variables and variables selected by Lasso and then used to match the control group. The cumulative incidence curve and Gray's test were employed to analyse the effect and prognosis of intra-aortic balloon counterpulsation on mortality. RESULTS: A total of 1962 acute myocardial infarction cases admitted between May 2015 and November 2018 were identified, and 223 cases with acute myocardial infarction complicated by cardiogenic shock were included as the study cohort, which contained 34 cases that received IABP and 189 cases that did not receive IABP. Patients with higher alanine aminotransferase (OR = 1.93, 95% CI 1.29-2.98), higher triglyceride (OR = 3.71, 95% CI 1.87-7.95), and higher blood glucose (OR = 1.08, 95% CI 0.99-1.18) had a higher probability of receiving intra-aortic balloon counterpulsation. In the propensity score matching analysis, 34 cases received intra-aortic balloon counterpulsation and 102 matched controls were included in the comparison. By comparing the cumulative incidence of in-hospital mortality, there was no statistically significant difference between the intra-aortic balloon counterpulsation group and matched control group (P = 0.454). CONCLUSION: The use of intra-aortic balloon counterpulsation may not improve the prognosis of the acute myocardial infarction complicated by cardiogenic shock patients.

Enhanced external counterpulsation: A unique treatment for the "No-Option" refractory angina patient.

WHAT IS KNOWN AND OBJECTIVES: Coronary artery disease (CAD) is the leading cause of death in the United States. For patients on whom guideline-driven measures have been tried, enhanced external counterpulsation (EECP) is the only truly noninvasive and safe intervention for which a reduction of angina symptoms and nitrate use, increased exercise tolerance, and improvement in myocardial ischaemia have been shown. The objective of this study was to demonstrate, by way of literature review, the efficacy of EECP as a treatment modality for the relief of refractory angina and improvement in quality of life in CAD patients. METHODS: This article reviewed the safety and efficacy of EECP in patients with refractory angina, by conducting a sweeping search and analysis of existing published literature. RESULTS AND DISCUSSION: Critical review of a multitude of studies revealed that EECP consistently reduces angina pectoris, extends time to exercise-induced ischaemia, decreases dependency on nitroglycerine for frequent chest pain, increases maximum workload, and improves the quality of life in patients with symptomatic stable angina. The literature reviewed also indicated that EECP is well-tolerated by the vast majority of patients, with relatively few adverse events reported. CONCLUSION: The present study suggests that EECP is a safe and likely best available method of treatment for patients presenting with symptomatic CAD not amenable to further revascularization.

Effects of external counter-pulsation on endothelial function assessed by peripheral artery tonometry, levels of glycaemia and metabolic markers in individuals with type 2 diabetes mellitus.

BACKGROUND AND AIMS: External counter-pulsation (ECP) generates sheer stress thereby improving endothelial function and anginal symptoms in coronary artery disease. Endothelial dysfunction is also involved in the pathogenesis of T2DM. The aim of this pilot study was to investigate the use of ECP at different doses in improving endothelial function and glycaemic markers in T2DM. METHODS: This prospective study involved 46 subjects with T2DM randomly assigned to receive 35 sessions of ECP at different regimens (0.5 h versus 1 h) and duration (7 versus 12 weeks). Endothelial function was evaluated by reactive hyperaemia index (RHI) via peripheral arterial tonometry at the start, midpoint and end of study. Other secondary outcomes included fasting glucose, HOMA-IR, HbA1c, blood pressure, lipid profile, weight and vibration sense. RESULTS: There was no change in RHI across all 3 regimens of ECP individually or collectively at the end of the study (ΔRHI +0.01%, p = 0.458). Glycaemic markers also remained unchanged at endpoint. Subgroup analysis showed an improvement in RHI (ΔRHI +20.6%, p = 0.0178) in subjects with more severe endothelial dysfunction at baseline. CONCLUSION: ECP did not show a beneficial effect on endothelial function or glycemic control in this South-East Asian population with T2DM at any of the three regimens. This may partly be explained by less severe endothelial dysfunction and less insulin resistance in our population at baseline.