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.

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).

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 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.

Enhanced external counterpulsation improves cardiac function in Beagles after cardiopulmonary resuscitation

The aim of this study was to investigate the influence of enhanced external counterpulsation (EECP) on the cardiac function of beagle dogs after prolonged ventricular fibrillation. Twenty-four adult male beagles were randomly divided into control and EECP groups. Ventricular fibrillation was induced in the animals for 12 min, followed by 2 min of cardiopulmonary resuscitation. They then received EECP therapy for 4 h (EECP group) or not (control group). The hemodynamics was monitored using the PiCCO2 system. Blood gas and hemorheology were assessed at baseline and at 1, 2, and 4 h after return of spontaneous circulation (ROSC). The myocardial blood flow (MBF) was quantified by 18F-flurpiridaz PET myocardial perfusion imaging at baseline and 4 h after ROSC. Survival time of the animals was recorded within 24 h. Ventricular fibrillation was successfully induced in all animals, and they achieved ROSC after cardiopulmonary resuscitation. Survival time of the control group was shorter than that of the EECP group [median of 8 h (min 8 h, max 21 h) vs median of 24 h (min 16 h, max 24 h) (Kaplan Meyer plot analysis, P=0.0152). EECP improved blood gas analysis findings and increased the coronary perfusion pressure and MBF value. EECP also improved the cardiac function of Beagles after ROSC in multiple aspects, significantly increased blood flow velocity, and decreased plasma viscosity, erythrocyte aggregation index, and hematocrit levels. EECP improved the hemodynamics of beagle dogs and increased MBF, subsequently improving cardiac function and ultimately improving the survival time of animals after ROSC.

Successful Use of Intra-aortic Balloon Counterpulsation for Systemic Ventricular Failure Following Total Pericardiectomy for Calcific Chronic Constrictive Pericarditis.

We report two male patients aged 18 and 19 years, respectively, undergoing total pericardiectomy for chronic calcific constrictive pericarditis who developed systemic ventricular failure unresponsive to medical management following surgery. The failing circulation was successfully reestablished using intra-aortic balloon counterpulsation. Aortic counterpulsation facilitates recovery of ventricular function and appears to be a reasonable alternative in select instances of refractory cardiac failure following pericardiectomy.

Superior mesenteric flow pattern during counterpulsation: is simply a shorter balloon the solution for visceral hypoperfusion?

OBJECTIVES: We studied the flow pattern in the superior mesenteric artery (SMA) during intra-aortic balloon pump support, comparing 2 intra-aortic balloons of 2 different lengths. METHODS: Sixteen Landrace pigs (mean weight 84.0 kg ± 6.0) were used in this study. The animals were randomly assigned to 2 groups: group 1 received an 8-Fr, 40-ml standard balloon; group 2 received an 8-Fr, 40-ml short balloon. SMA flow was measured during early, mid- and telediastole. RESULTS: The standard balloon led to a reduction in SMA flow in early diastole (P < 0.001), a negative flow in mid-diastole (P < 0.001) and a reincrease in telediastole (P < 0.001). In contrast, in early diastole a significant reduction was observed with the short balloon (P < 0.001), followed by another drop in mid-diastole (P < 0.001), without reaching negative values and by a telediastolic increase (P < 0.001). SMA flows were comparable between balloons during early diastole (P = 0.66), whereas they were higher with the short balloon during mid (P < 0.001) and telediastole (P = 0.02). Overall, the diastolic area was significantly larger when the short balloon was used (P < 0.001). Finally, during counterpulsation, mesenteric resistances increased significantly (P < 0.001), although, with the short balloon, they were lower than with the standard balloon (P = 0.01). CONCLUSIONS: Despite better overall mean mesenteric diastolic flow, the short balloon leads to early- and mid-diastolic flow reduction, although to a lesser extent than the standard intra-aortic balloon pump balloon. Our data are a call for improvement in the design of the short balloon.

Non-PCI/CABG therapies for refractory angina.

Angina persists for many patients despite modern medical therapy and/or revascularization, and this is referred to as refractory angina. All patients with refractory angina must be treated with aggressive risk factor modification plus optimized medical management. ß-Blockers and nitrates are usually first-line agents; however most patients require multiple medications for refractory symptom control. Novel agents, such as ranolazine and ivabradine, as well as non-pharmacologic therapies, such as enhanced external counterpulsation and cardiac rehabilitation, may provide relief or reduction of angina. Other standard treatments such as antiplatelet therapy, lipid reduction therapy, blood pressure control, diabetes control, smoking cessation, and wei1ght control should be part of the management of refractory angina as well.

Acute Hemodynamic Effects of Intra-aortic Balloon Counterpulsation Pumps in Advanced Heart Failure.

BACKGROUND: The utility of intra-aortic balloon counterpulsation pumps (IABPs) in low cardiac output states is unknown and no studies have explored the impact of IABP therapy on ventricular workload in patients with advanced heart failure (HF). For these reasons, we explored the acute hemodynamic effects of IABP therapy in patients with advanced HF. METHODS: We prospectively studied 10 consecutive patients with stage D HF referred for IABP placement before left ventricular assist device (LVAD) surgery and compared with 5 control patients with preserved left ventricular (LV) ejection fraction (EF) who did not receive IABP therapy. Hemodynamics were recorded using LV conductance and pulmonary artery catheters. Cardiac index (CI)-responder and CI-nonresponder status was assigned a priori as being "equal to or above" or below the median of the IABP effect on CI, respectively, within 24 hours after IABP activation. RESULTS: Compared with controls, patients with advanced HF had lower LVEF, lower LV end-systolic pressure, lower LV stroke work, and higher LV end-diastolic pressures and volumes before IABP activation. IABP activation reduced LV stroke work primarily by reducing end-systolic pressure. IABP therapy increased CI by a median of 20% as well as increased diastolic pressure time index and the myocardial oxygen supply:demand ratio. Compared with CI-nonresponders, CI-responders had higher systemic vascular resistance, lower right heart filling pressures, and a trend toward lower left heart filling pressures with improved indices of right heart function. Compared with CI-nonresponders, the diastolic pressure time index was increased among CI-responders. CONCLUSIONS: IABP therapy may be effective at reducing LV stroke work, increasing CI, and favorably altering the myocardial oxygen supply:demand ratio in patients with advanced HF, especially among patients with low right heart filling pressures and high systemic vascular resistance.

Sunshine Heart C-Pulse: device for NYHA Class III and ambulatory Class IV heart failure.

Advanced heart failure (HF) patients not meeting criteria for ventricular assist device or heart transplant with life-limiting symptoms are limited to medical and resynchronization therapy. The Sunshine Heart C-Pulse, based on intra-aortic balloon pump physiology, provides implantable, on-demand, extra-aortic counterpulsation, which reduces afterload and improves cardiac perfusion in New York Heart Association Class III and ambulatory Class IV HF. The C-Pulse reduces New York Heart Association Class, improves 6-min walk distances, inotrope requirements and HF symptom questionnaires. Advantages include shorter operative times without cardiopulmonary bypass, no reported strokes or thrombosis and no need for anticoagulation. Driveline exit site infections, inability to provide full circulatory support and poor function with intractable arrhythmias remain concerns. Current randomized controlled studies will evaluate long-term efficacy and safety compared with medical and resynchronization therapy.

Accuracy of Continuous Cardiac Output Measurement With the LiDCOplus System During Intra-Aortic Counterpulsation After Cardiac Surgery.

OBJECTIVE: To evaluate the effect of intra-aortic counterpulsation on precision, accuracy, and concordance of continuous pulse contour cardiac output determined using LiDCOplus (LiDCO Group, London). DESIGN: Prospective trial. SETTING: University hospital critical care unit. PARTICIPANTS: Patients with intra-aortic balloon pump support in the 1:1 mode after elective or urgent cardiac surgery. INTERVENTIONS: Lithium dilution calibrated pulse contour cardiac output was compared with pulmonary artery bolus thermodilution cardiac output during hemodynamically stable conditions in the course of standardized postoperative management. MEASUREMENTS AND MAIN RESULTS: Fifty-one paired measurements demonstrated good correlation between the 2 methods (r = 0.88, p<0.001). Mean bias was -0.14±0.81 L/min, limits of agreement 1.48 to -1.77 L/min, and percentage error 28%. Concordance between the 2 techniques regarding directional changes>±10% cardiac output was 100% (p = 0.008). Trending ability was moderate when paired cardiac output changes were assessed using linear regression, 4-quadrant table, and polar plots. When changes <±10% of the reference cardiac output were excluded, 90% of the data pairs still lay within the 30° radial limits. Optimal timing of the balloon pump was indispensable for proper determination of pulse contour cardiac output. CONCLUSIONS: Because of the LiDCOplus-specific algorithm in determining stroke volume from the arterial pulse waveform, which differs from other devices, accuracy and precision of continuous pulse contour cardiac output only are affected insignificantly by intra-aortic counterpulsation. The authors nevertheless caution that the device should be recalibrated after major hemodynamic alterations or otherwise inexplicable changes of the pulse contour cardiac output to improve trending.

Comparison of effects of extra-thoracic paraaortic counterpulsation to intraaortic balloon pump on circulatory support in acute heart failure.

BACKGROUND: Previously designed intra-thoracic paraaortic counterpulsation device has limited stroke volume and may depress the lung to cause complications. The purpose of this study was to evaluate the hemodynamic effects of an extra-thoracic paraaortic counterpulsation device (ETPACD) in comparison to intraaortic balloon pump (IABP) in an animal model with acute heart failure. METHODS: The acute heart failure model was successfully induced by snaring branch of anterior descending coronary artery in sheep (weighting, 38-50 kg, n = 8). The ETPACD is a single port, 65-ml stroke volume blood chamber designed to be connected to descending aorta through a valveless graft and placed extra-thorax. In comparison, a standard clinical 40-ml IABP was placed in the descending aorta. The hemodynamic indices of both devices were recorded during counterpulsation assistance. Two of the sheep were allowed to survive for 1 week to examine the prolonged effect. RESULTS: Both ETPACD and IABP increased cardiac output with higher effect of ETPACD (13.52 % vs. 8.19 % in IABP, P < 0.05) and on mean diastolic aortic pressure (26.73 % vs. 12.58 % in IABP, P < 0.01). Both ETPACD and IABP also produced a greater reduction in left ventricular end-diastolic pressure (26.77 % vs. 23.08 %, P > 0.05). The ETPACD increased left carotid artery flow more significantly the IABP (18.00 % vs. 9.19 % , P < 0.05). In two of the sheep allowed to survive for 1 week, the device worked well with no complications and there was no thrombus formation in the chamber of ETPACD. CONCLUSIONS: This study demonstrated that both ETPACD and IABP provided benefit of circulatory support in acute heart failure with better effect on hemodynamic parameters provided by ETPACD. Therefore, ETPACD with theoretical larger stroke volume may become a promising counterpulsation device for treatment of heart failure.

Increasing pressure of external counterpulsation augments blood pressure but not cerebral blood flow velocity in ischemic stroke.

External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion but the optimal use of ECP in ischemic stroke has not been well documented. We aimed to investigate the effects of ECP treatment pressure on cerebral blood flow and blood pressure (BP). We recruited 38 ischemic stroke patients with large artery occlusive disease and 20 elderly controls. We commenced ECP treatment pressure at 150 mmHg and gradually increased to 187.5, 225 and 262.5 mmHg. Mean cerebral blood flow velocities (CBFV) of bilateral middle cerebral arteries and continuous beat-to-beat BP were recorded before ECP and during each pressure increment for 3 minutes. Patient CBFV data was analyzed based on whether it was ipsilateral or contralateral to the infarct. Mean BP significantly increased from baseline in both stroke and control groups after ECP commenced. BP increased in both groups following raised ECP pressure and reached maximum at 262.5 mmHg (patients 16.9% increase versus controls 16.52%). The ipsilateral CBFV of patients increased 5.15%, 4.35%, 4.55% and 3.52% from baseline under the four pressures, respectively. All were significantly higher than baseline but did not differ among different ECP pressures; contralateral CBFV changed likewise. Control CBFV did not increase under variable pressures of ECP. ECP did increase CBFV of our patients to a roughly equal degree regardless of ECP pressure. Among the four ECP pressures tested, we recommend 150 mmHg as the optimal treatment pressure for ischemic stroke due to higher risks of hypertension-related complications with higher pressures.

Aortic counterpulsation: C-pulse and other devices for cardiac support.

Heart failure is the leading cause of hospitalization in the USA. Despite major advances in the medical and device-related therapy including chronic resynchronization therapy for management of heart failure, significant number of patients eventually require advanced cardiac therapy including mechanical circulatory support or heart transplant. Heart transplant is a gold standard for end-stage heart failure but is limited by the donor heart shortage creating a definite need for alternative effective therapies. The earliest and most common form of mechanical circulatory support is counterpulsation therapy. Annually, more than 150,000 patients worldwide receive counterpulsation therapy for various indications including cardiogenic shock or severe left ventricular dysfunction (Nanas and Moulopoulos in Cardiology, 84:156-167, 1994) and many thousands of lives are saved each year (65 % survival) (Torchiana et al. in Journal of Thoracic and Cardiovascular Surgery, 113(4):758-764, 1997). There are different types of aortic counterpulsation devices. Here, we will give an overview of different counterpulsation devices with focus on C-Pulse device. Extra-aortic balloon counterpulsation, C-Pulse (Sunshine Heart Inc., Eden Prairie, MN), is an important and novel approach in the management of patients with advanced heart failure who remain symptomatic despite optimum medical and device-based therapy. C-Pulse is designed to provide permanent, long-term, continuous partial circulatory support for New York Heart Association class III and ambulatory class IV heart failure patients. C-Pulse is a nonblood-contacting counterpulsation using an inflatable cuff around the ascending aorta, extra-aortic balloon (EAB) counterpulsation device. A pivotal, multicenter US study to assess the safety and efficacy of C- Pulse in patient with Stage C and NYHA Class III or ambulatory Class IV heart failure is in progress.

Therapeutic approaches in the stimulation of the coronary collateral circulation.

Arteriogenesis as a way to restore blood flow after arterial occlusion has been under investigation for the treatment of coronary artery disease (CAD) for decades. Therapeutic approaches so far have included delivery of cytokines and growth factors as well as mechanical stimulation such as external counterpulsation. As knowledge on the mechanisms of arteriogenesis expanded, new therapeutic approaches have emerged. This review summarizes recent attempts to stimulate the growth of the coronary vasculature and discusses their potential in clinical application. This article also delivers an overview of current studies and trials on coronary arteriogenesis.

Concept and first experimental results of a new ferromagnetic assist device for extra-aortic counterpulsation.

OBJECTIVES: Based on a ferromagnetic silicone cuff for extra-aortic counterpulsation, a new assist device concept was developed. The driving force is generated by an external magnetic field, which leads to contraction of a soft magnetic cuff. The force generation capacity of the device was tested in a silicone aorta model. METHODS: Magnetic elastomers can be constructed through dispersion of micro- or nanoparticles in polymer matrices and were designed to act as soft actuators. Two magnetically active silicone cuffs were produced with a nanomagnet loading of 250 wt% (Cuff 1) and a micromagnet loading of 67 wt% (Cuff 2). The magnetic cuffs were applied on a silicone aorta model and contracted against hydrostatic pressure. RESULTS: A full contraction of Cuff 1 was possible against a maximal hydrostatic pressure of 30 cmH2O (22 mmHg) at a magnetic flux density of 0.4 T (Tesla) and 65 cmH2O (48 mmHg) at a magnetic flux density of 1.2 T. A 50% contraction of Cuff 2 was possible against a maximal hydrostatic pressure of 80 cmH2O (59 mmHg) at a magnet-cuff-distance (MCD) of 0 cm. At MCDs of 1 and 2 cm a 50% contraction was possible against 33 cmH2O (24 mmHg) and 10 cmH2O (7 mmHg), respectively. CONCLUSIONS: Combining the advantages of magnetic elastomers with the principle of extra-aortic counterpulsation in a new assist device concept avoids the need for anticoagulation (no contact with bloodstream). With regard to the magnetic principle of action, no intra- to extracorporeal connection is needed. More experimental work is needed to further increase the force generated by the silicone cuff and to transfer the device concept into an in vivo setting.

Effect of enhanced external counterpulsation treatment on renal function in cardiac patients.

BACKGROUND: Enhanced external counterpulsation (EECP) enhances coronary perfusion and reduces left ventricular afterload. However, the role of EECP on renal function in cardiac patients is unknown. Our aim was to assess renal function determined by serum cystatin C in cardiac patients before and after EECP treatment. METHODS: A prospective observational longitudinal study was conducted in order to evaluate renal function using serum cystatin C (Cys C) and estimated glomerular filtration rate (GFR) after 35 sessions of EECP treatment in 30 patients with chronic stable angina and/or heart failure. The median (IQR) time for follow-up period after starting EECP treatment was 16 (10-24) months. RESULTS: Cys C significantly declined from 1.00 (0.78-1.31) to 0.94 (0.77-1.27) mg/L (p < 0.001) and estimated GFR increased from 70.47 (43.88-89.41) to 76.27 (49.02-91.46) mL/min/1.73 m(2) (p = 0.006) after EECP treatment. Subgroup analysis showed that patients with baseline GFR <60 mL/min/1.73 m(2) or NT-proBNP >125 pg/mL had a significant decrease in Cys C when compared to other groups (p < 0.01). CONCLUSIONS: The study demonstrated that EECP could improve long-term renal function in cardiac patients especially in cases with declined renal function or with high NT-proBNP. TRIAL REGISTRATION: The study was registered in the clinical trial as International Standard Randomized Controlled Trial Number ISRCTN11560035.