left ventricular unloading Dotaz Zobrazit nápovědu
The main reason for the emergency implantation of venoarterial extracorporeal membrane oxygenation (VA-ECMO) is the restoration of adequate systemic perfusion, while protecting the failing heart and promoting myocardial recovery are equally important goals. Following initial haemodynamic stabilization and often the urgent revascularization of the culprit lesion, the clinical focus is then directed towards the most efficient strategy for cardioprotection. Frequent echocardiography measurements may help to estimate the degree of unwanted left ventricular (LV) overloading during VA-ECMO. Additionally, the estimation of high LV filling pressures by Doppler echocardiography or their (in-)direct measurement using a dedicated surgical left atrial pressure line and conventional pulmonary artery catheter in a wedge position or a pigtail catheter in the left ventricle can be performed. Mechanical overload of the left ventricle is the major adverse effect and an obvious mechanistic and prognostic challenge of contemporary ECMO care. Many efforts are under way to overcome this phenomenon by LV unloading, which was effectively achieved by the current combined approach using an axial decompression device, while novel technical developments and approaches are tested and urgently anticipated. The aim of this report is to introduce in depth pathophysiological background, current concepts, and future perspectives in LV unloading strategies.
- Klíčová slova
- Cardiac arrest, Cardiogenic shock, Cardioprotection, Oxygenation, Unloading, Venoarterial ECMO,
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: The aim of this study was to quantify and understand the unloading effect of percutaneous balloon atrial septostomy (BAS) in acute cardiogenic shock (CS) treated with venoarterial (VA) extracorporeal membranous oxygenation (ECMO). BACKGROUND: In CS treated with VA ECMO, increased left ventricular (LV) afterload is observed that commonly interferes with myocardial recovery or even promotes further LV deterioration. Several techniques for LV unloading exist, but the optimal strategy and the actual extent of such procedures have not been fully disclosed. METHODS: In a porcine model (n = 11; weight 56 kg [53-58 kg]), CS was induced by coronary artery balloon occlusion (57 minutes [53-64 minutes]). Then, a step-up VA ECMO protocol (40-80 mL/kg/min) was run before and after percutaneous BAS was performed. LV pressure-volume loops and multiple hemoglobin saturation data were evaluated. The Wilcoxon rank sum test was used to assess individual variable differences. RESULTS: Immediately after BAS while on VA ECMO support, LV work decreased significantly: pressure-volume area, end-diastolic pressure, and stroke volume to ∼78% and end-systolic pressure to ∼86%, while superior vena cava and tissue oximetry did not change. During elevating VA ECMO support (40-80 mL/kg/min) with BAS vs without BAS, we observed 1) significantly less mechanical work increase (122% vs 172%); 2) no end-diastolic volume increase (100% vs 111%); and 3) a considerable increase in end-systolic pressure (134% vs 144%). CONCLUSIONS: In acute CS supported by VA ECMO, atrial septostomy is an effective LV unloading tool. LV pressure is a key component of LV work load, so whenever LV work reduction is a priority, arterial pressure should carefully be titrated low while maintaining organ perfusion.
- Klíčová slova
- animal model, atrial septostomy, cardiogenic shock, left ventricular unloading, venoarterial extracorporeal membrane oxygenation,
- MeSH
- kardiogenní šok * diagnóza terapie MeSH
- lidé MeSH
- mimotělní membránová oxygenace * metody MeSH
- modely nemocí na zvířatech MeSH
- prasata MeSH
- vena cava superior MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The peripheral venoarterial extracorporeal life support (V-A ECLS) in cardiogenic shock (CS) may lead to LV overload. The transaortic suction device (Impella, ABIOMED Inc., Danvers, MA) was compared to the pulmonary artery (PA) drainage, for LV unloading efficacy during V-A ECLS in a porcine cardiogenic shock model. A dedicated CS model included 12 swine (21 ± 1.8-week-old and weighing 54.3 ± 4.6 kg) supported with V-A ECLS and randomized to Impella or PA-related LV drainage. LV unloading and end-organ perfusion were evaluated through the PA catheter and LV pressure/volume analysis. The LV end-diastolic volume sharply dropped with Impella (143.6 ± 67.4 vs 123 ± 75.7 mL) compared to a slight decrease in the PA cannula group (134.1 ± 39.9 vs 130.1 ± 34.7 mL), resulting in an overall stroke work and pressure-volume area reductions with both techniques. However, stroke work reduction was more significant in the Impella group (V-A ECLS 3998.8 ± 2027.6 vs V-A ECLS + Impella 1796.9 ± 1033.9 mm Hg × mL, P = 0.016), leading to a more consistent pressure-volume area reduction (Impella reduction 34.7% vs PA cannula reduction 9.7%) In terms of end organ perfusion, central and mixed O2 saturation improved with V-A ECLS, and subsequently, remaining unchanged with either Impella or PA cannula as unloading strategy (SVmO2: Impella 86.0 ± 5.8 vs 87.8 ± 5.8; PA cannula 82.5 ± 10.7 vs 82.5 ± 11.3 %). Transaortic suction and PA drainage provided effective LV unloading during V-A ECLS while maintaining adequate end-organ perfusion. Impella provides a greater LV unloading effect and reduces more effectively the total LV stroke work.
- Klíčová slova
- CS porcine model, Cardiogenic shock, ECLS, Impella, LV unloading, LV venting, Pulmunary drainage,
- MeSH
- arteria pulmonalis diagnostické zobrazování MeSH
- drenáž MeSH
- kardiogenní šok diagnóza etiologie terapie MeSH
- mimotělní membránová oxygenace * MeSH
- podpůrné srdeční systémy * MeSH
- prasata MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Phosphodiesterase-5A inhibitors (PDE5i) are sometimes used in patients with advanced heart failure with reduced ejection fraction before heart transplant or left ventricular assist device implantation to decrease right ventricular (RV) afterload and mitigate the risk of right heart failure. Conflicting evidence exists regarding the impact of these drugs on RV contractility. The aim of this study was to explore the acute effects of PDE5i on ventricular-vascular coupling and load-independent RV contractility. METHODS: Twenty-two patients underwent right heart catheterization and gated equilibrium blood pool single photon emission computed tomography, before and after 20 mg intravenous sildenafil. Single photon emission computed tomography and right heart catheterization-derived data were used to calculate RV loading and contractility. RESULTS: PDE5i induced a decrease in the right atrial pressure (-43%), pulmonary artery (PA) mean pressure (-26%), and PA wedge pressure (PAWP; -23%), with favorable reductions in pulmonary vascular resistance (-41%) and PA elastance (-40%), and increased cardiac output (+13%) (all P < 0.01). The RV ejection fraction increased with sildenafil (+20%), with no change of RV contractility (P = 0.74), indicating that the improvement in the RV ejection fraction was related to enhanced RV-PA coupling (r = 0.59, P = 0.004) by a decrease in the ventricular load. RV diastolic compliance increased with sildenafil. The decrease in the PAWP correlated with RV end-diastolic volume decrease; no relationship was observed with the change in LV transmural pressure, suggesting decreased pericardial constraint. CONCLUSIONS: Acute PDE5i administration has profound RV afterload-reducing effects, improves the RVEF, decreases RV volumes, and decreases the PAWP, predominantly through relief of pericardial constraint, without effects on RV chamber contractility. These findings support further study of PDE5i in protection of RV function in advanced heart failure with reduced ejection fraction who are at risk of RV failure.
- Klíčová slova
- PDE5 inhibitors, LVAD, Right ventricle, heart failure, pulmonary hypertension,
- MeSH
- arteria pulmonalis MeSH
- dysfunkce pravé srdeční komory * diagnostické zobrazování farmakoterapie MeSH
- funkce pravé komory srdeční MeSH
- lidé MeSH
- sildenafil citrát MeSH
- srdeční selhání * farmakoterapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- sildenafil citrát MeSH
BACKGROUND: Veno-arterial extracorporeal membrane oxygenation can be vital to support patients in severe or rapidly progressing cardiogenic shock. In cases of left ventricular distension, left ventricular decompression during veno-arterial extracorporeal membrane oxygenation may be a crucial factor influencing the patient outcome. Application of a double lumen arterial cannula for a left ventricular unloading is an alternative, straightforward method for left ventricular decompression during extracorporeal membrane oxygenation in a veno-arterial configuration. OBJECTIVES: The purpose of this article is to use a mathematical model of the human adult cardiovascular system to analyze the left ventricular function of a patient in cardiogenic shock supported by veno-arterial extracorporeal membrane oxygenation with and without the application of left ventricular unloading using a novel double lumen arterial cannula. METHODS: A lumped model of cardiovascular system hydraulics has been coupled with models of non-pulsatile veno-arterial extracorporeal membrane oxygenation, a standard venous cannula, and a drainage lumen of a double lumen arterial cannula. Cardiogenic shock has been induced by decreasing left ventricular contractility to 10% of baseline normal value. RESULTS: The simulation results indicate that applying double lumen arterial cannula during veno-arterial extracorporeal membrane oxygenation is associated with reduction of left ventricular end-systolic volume, end-diastolic volume, end-systolic pressure, and end-diastolic pressure. CONCLUSIONS: A double lumen arterial cannula is a viable alternative less invasive method for left ventricular decompression during veno-arterial extracorporeal membrane oxygenation. However, to allow for satisfactory extracorporeal membrane oxygenation flow, the cannula design has to be revisited.
- Klíčová slova
- Extracorporeal membrane oxygenation, cannula, circulation, double lumen cannula, model, modelica,
- MeSH
- chirurgická dekomprese přístrojové vybavení metody MeSH
- design vybavení metody MeSH
- dospělí MeSH
- dysfunkce levé srdeční komory chirurgie MeSH
- kanyla * MeSH
- kardiogenní šok * patofyziologie chirurgie MeSH
- katetrizace centrálních vén přístrojové vybavení metody MeSH
- katetrizace metody MeSH
- lidé MeSH
- mimotělní membránová oxygenace * přístrojové vybavení metody MeSH
- počítačová simulace MeSH
- reprodukovatelnost výsledků MeSH
- srdeční komory patofyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
A 19-year-old woman with no previous cardiac history was admitted to the hospital with third-degree atrioventricular block and left ventricular dysfunction. Her condition quickly deteriorated to severe biventricular failure and cardiogenic shock requiring mechanical circulatory support. An endomyocardial biopsy revealed lymphocytic myocarditis with no PCR-detectable viral genomes, with CD8 T-cell predominance and pro-inflammatory macrophage expansion shown by myocardial flow cytometry. The therapy consisted of immunosuppression (high-dose methylprednisolone) and temporary mechanical circulatory support with enhanced ability to achieve left ventricular unloading by combination of extracorporeal membrane oxygenation with Impella (ECMELLA). After 2 weeks of support, complete and sustained recovery from myocarditis was observed.
- Klíčová slova
- Extracorporeal membrane oxygenation (ECMO), Fulminant myocarditis, Immunosuppression, Mechanical circulatory support,
- MeSH
- CD8-pozitivní T-lymfocyty MeSH
- dospělí MeSH
- imunosupresivní léčba MeSH
- lidé MeSH
- mladý dospělý MeSH
- myokarditida * diagnóza etiologie terapie MeSH
- podpůrné srdeční systémy * MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- práce podpořená grantem MeSH
Ventricular assist devices (VAD) have recently established themselves as an irreplaceable therapeutic modality of terminal heart failure. Because of the worldwide shortage of donors, ventricular assist devices play a key role in modern heart failure therapy. Some clinical data have revealed the possibility of cardiac recovery during VAD application. On the other hand, both clinical and experimental studies indicate the risk of the cardiac atrophy development, especially after prolonged mechanical unloading. Little is known about the specific mechanisms governing the unloading-induced cardiac atrophy and about the exact ultrastructural changes in cardiomyocytes, and even less is known about the ways in which possible therapeutical interventions may affect heart atrophy. One aim of this review was to present important aspects of the development of VAD-related cardiac atrophy in humans and we also review the most significant observations linking clinical data and those derived from studies using experimental models. The focus of this article was to review current methods applied to alleviate cardiac atrophy which follows mechanical unloading of the heart. Out of many pharmacological agents studied, only the selective beta2 agonist clenbuterol has been proved to have a significantly beneficial effect on unloading-induced atrophy. Mechanical means of atrophy alleviation also seem to be effective and promising.
- MeSH
- agonisté adrenergních beta-receptorů terapeutické užití MeSH
- atrofie etiologie patologie terapie MeSH
- klenbuterol terapeutické užití MeSH
- lidé MeSH
- podpůrné srdeční systémy škodlivé účinky MeSH
- srdeční selhání etiologie patologie terapie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- agonisté adrenergních beta-receptorů MeSH
- klenbuterol MeSH
AIMS: Patients on chronic haemodialysis have a wide range of changes in cardiac function and structure, including left ventricular hypertrophy, dilation and diastolic dysfunction or pulmonary hypertension. All these changes were linked to increased mortality in previous studies. High-flow arteriovenous fistulas (AVF) are supposed to be a factor contributing to their development. This study investigated the early effect of surgical AVF blood flow (Qa) reduction on these changes in patients with or without heart failure changes. METHODS AND RESULTS: Forty-two patients in chronic haemodialysis programme with high-flow AVF (Qa over 1500 mL/min), indicated for surgery for ≥1 of the following indications: 1.manifest heart failure; 2.hand ischemia; 3.advanced structural heart changes detected by echocardiography. The patients underwent echocardiography on selection visit, before blood flow reducing surgery and six weeks thereafter. The Qa reduction led to decrease of left ventricular mass (p = 0.02), end-diastolic volume (p = 0.008), end-diastolic diameter (p = 0.003) and left atrial volume (p = 0.0006). Diastolic function improved. Similarly, right ventricular diameter and right atrial volume decreased (p = 0.000001 and 0.00009, respectively) together with the decrease of estimated pulmonary artery systolic pressure. 81% of patients suffered from pulmonary hypertension prior to surgery, only 36% thereafter. CONCLUSION: The surgical restriction of the hyperkinetic circulation leads to several improvements of heart structure and function, which was linked to higher mortality in other studies. The beneficial effect of Qa reduction is present even in patients without symptoms of heart failure. The contribution of AVF must be considered with structural or functional heart changes.
- Klíčová slova
- Echocardiography, Haemodialysis, High flow arteriovenous fistula, High-output heart failure,
- MeSH
- arteriovenózní zkrat * škodlivé účinky MeSH
- dialýza ledvin škodlivé účinky MeSH
- echokardiografie MeSH
- hemodynamika MeSH
- lidé MeSH
- srdeční selhání * diagnostické zobrazování terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
An important complication of the prolonged left ventricle assist device support in patients with heart failure is unloading-induced cardiac atrophy which proved resistant to various treatments. Heterotopic heart transplantation (HTx) is the usual experimental model to study this process. We showed previously that implantation of the newly designed intraventricular spring expander can attenuate the atrophy when examined after HTx in the failing heart (derived from animals with established heart failure). The present study aimed to examine if enhanced isovolumic loading achieved by implantation of the expander would attenuate cardiac post-HTx atrophy also in the healthy heart. Cardiac atrophy was assessed as the ratio of the transplanted-to-native heart weight (HW) and its degree was determined on days 7, 14, 21 and 28 after HTx. The transplantation resulted in 32±3, 46±2, 48±3 and 46±3 % HW loss when measured at the four time points; implantation of the expander had no significant effect on these decreases. We conclude that enhanced isovolumic loading achieved by intraventricular implantation of the expander does not attenuate the development of cardiac atrophy after HTx in the healthy heart. This indicates that such an approach does not represent a useful therapeutic measure to attenuate the development of unloading-induced cardiac atrophy.
- MeSH
- atrofie patologie chirurgie MeSH
- heterotopická transplantace přístrojové vybavení metody MeSH
- krysa rodu Rattus MeSH
- myokard patologie MeSH
- podpůrné srdeční systémy * MeSH
- potkani inbrední LEW MeSH
- srdce diagnostické zobrazování MeSH
- transplantace srdce přístrojové vybavení metody MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The term 'mechanosensation' describes the capacity of cells to translate mechanical stimuli into the coordinated regulation of intracellular signals, cellular function, gene expression and epigenetic programming. This capacity is related not only to the sensitivity of the cells to tissue motion, but also to the decryption of tissue geometric arrangement and mechanical properties. The cardiac stroma, composed of fibroblasts, has been historically considered a mechanically passive component of the heart. However, the latest research suggests that the mechanical functions of these cells are an active and necessary component of the developmental biology programme of the heart that is involved in myocardial growth and homeostasis, and a crucial determinant of cardiac repair and disease. In this Review, we discuss the general concept of cell mechanosensation and force generation as potent regulators in heart development and pathology, and describe the integration of mechanical and biohumoral pathways predisposing the heart to fibrosis and failure. Next, we address the use of 3D culture systems to integrate tissue mechanics to mimic cardiac remodelling. Finally, we highlight the potential of mechanotherapeutic strategies, including pharmacological treatment and device-mediated left ventricular unloading, to reverse remodelling in the failing heart.
- MeSH
- fibroblasty patologie MeSH
- lidé MeSH
- myokard patologie MeSH
- remodelace komor MeSH
- srdeční komory patologie MeSH
- srdeční selhání * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH