Right Ventricular Failure After Left Ventricular Assist Device

Cardiac replacement therapy: Critical issues and future perspectives of heart transplantation and artificial heart

Diagnostic and therapeutic advances in the cardiovascular field have caused a progressive reduction in mortality from acute causes, with an ever-increasing chronicity of cardiovascular pathologies. In recent years, mechanical supports have played a fundamental role, allowing the patient to be stabilized in the most critical phase of acute heart failure (AHF) and acting as a "bridge" for definitive therapies. Heart transplantation (HTx) is the gold-standard treatment for end-stage HF, but it is burdened by a series of critical issues that limit its use, first of all the shortage of grafts. It also requires the patient to take immunosuppressive therapy for life, which exposes him to a greater risk of infectious and oncological diseases. For these reasons, in the last years, mechanical supports are increasingly used as "destination therapy", alternatively to HTx. However, also mechanical supports are not free from critical issues that limit their use. In this review we aim to analyze critical issues and future perspectives of advanced HF therapies.

TOWARDS A UNIVERSAL DEFINITION FOR RIGHT HEART FAILURE:A WORK IN PROGRESS

BACKGROUND

Broadly speaking, right heart failure can be defined as a clinical syndrome with signs and symptoms of heart failure resulting from right ventricular dysfunction, as evidenced by abnormal structure or function. The heterogeneity of conditions associated with right heart failure combined with the challenges of characterizing the structural and functional relationships of the right ventricle make a singular definition of right heart failure elusive. We performed a concise scoping review of the literature that provides knowledge synthesis of right heart failure in different clinical populations, and extracted the recommended criteria to define the syndrome.

METHODS

Searches were conducted to identify reviews, guidelines, consensus statements, systematic reviews, meta-analysis and consensus statements concerning right heart or right ventricular failure in well described adult human disease populations from the previous 10 years. After removal of case reports and duplicates, publications describing syndromes in the context of left sided heart disease were also removed. Data extracted from selected manuscripts included the patient population and quantitative criteria to define right heart failure, categorized based on diagnostic modalities.

RESULTS

Of 9487 articles initially identified, 71 were selected for full text review. We found that the majority of the reviewed literature offered multi-faceted diagnostic approaches, including clinical, echocardiographic, hemodynamic and therapeutic characteristics, with unique additions or omissions depending on the clinical contexts. Nomenclature for right heart failure was variable and only 40% of articles articulated a narrative definition.

CONCLUSION

At this time, development of consistent criteria and a universal definition for right heart failure remains a work in process.

Right Heart Failure in the Intensive Care Unit: Etiology, Pathogenesis, Diagnosis, and Treatment

Right heart (RH) failure carries a high rate of morbidity and mortality. Patients who present with RH failure often exhibit complex aberrant cardio-pulmonary physiology with varying presentations. The treatment of RH failure almost always requires care and management from an intensivist. Treatment options for RH failure patients continue to evolve rapidly with multiple options available, including different pharmacotherapies and mechanical circulatory support devices that target various components of the RH circulatory system. An understanding of the normal RH circulatory physiology, treatment, and support options for the RH failure patients is necessary for all intensivists to improve outcomes. The purpose of this review is to provide clinical guidance on the diagnosis and management of RH failure within the intensive care unit setting, and to highlight the different pathophysiological manifestations of RH failure, its hemodynamics, and treatment options available at the disposal of the intensivist.

Effect of Oxidative Stress on Mitochondrial Damage and Repair in Heart Disease and Ischemic Events

The literature analysis conducted in this review discusses the latest achievements in the identification of cardiovascular damage induced by oxidative stress with secondary platelet mitochondrial dysfunction. Damage to the platelets of mitochondria as a result of their interactions with reactive oxygen species (ROS) and reactive nitrogen species (RNS) can lead to their numerous ischemic events associated with hypoxia or hyperoxia processes in the cell. Disturbances in redox reactions in the platelet mitochondrial membrane lead to the direct oxidation of cellular macromolecules, including nucleic acids (DNA base oxidation), membrane lipids (lipid peroxidation process) and cellular proteins (formation of reducing groups in repair proteins and amino acid peroxides). Oxidative changes in biomolecules inducing tissue damage leads to inflammation, initiating pathogenic processes associated with faster cell aging or their apoptosis. The consequence of damage to platelet mitochondria and their excessive activation is the induction of cardiovascular and neurodegenerative diseases (Parkinson's and Alzheimer's), as well as carbohydrate metabolism disorders (diabetes). The oxidation of mitochondrial DNA can lead to modifications in its bases, inducing the formation of exocyclic adducts of the ethano and propano type. As a consequence, it disrupts DNA repair processes and conduces to premature neoplastic transformation in critical genes such as the p53 suppressor gene, which leads to the development of various types of tumors. The topic of new innovative methods and techniques for the analysis of oxidative stress in platelet mitochondria based on methods such as a nicking assay, oxygen consumption assay, Total Thrombus formation Analysis System (T-Tas), and continuous-flow left ventricular assist devices (CF-LVADs) was also discussed. They were put together into one scientific and research platform. This will enable the facilitation of faster diagnostics and the identification of platelet mitochondrial damage by clinicians and scientists in order to implement adequate therapeutic procedures and minimize the risk of the induction of cardiovascular diseases, including ischemic events correlated with them. A quantitative analysis of the processes of thrombus formation in cardiovascular diseases will provide an opportunity to select specific anticoagulant and thrombolytic drugs under conditions of preserved hemostasis.

Right ventricular-pulmonary arterial coupling in patients with implanted left ventricular assist devices

OBJECTIVE

Both the right ventricular (RV) contractile function and pulmonary arterial (PA) pressure influence clinical outcomes in patients supported with left ventricular assist devices (LVADs), but the impact of RV-PA coupling is unknown. This study aimed to determine the prognostic impact of RV-PA coupling in patients with implanted LVADs.

METHODS

Patients with implanted third-generation LVADs were retrospectively enrolled. The RV-PA coupling was assessed preoperatively by the ratio of RV free wall strain (RVFWS) derived from speckle-tracking echocardiography and noninvasively measured peak RV systolic pressure (RVSP). The primary end point was a composite of all-cause mortality or right heart failure (RHF) hospitalization. Secondary end points consisted of all-cause mortality at a 12-month follow-up and RHF hospitalization.

RESULTS

A total of 103 patients were screened, and 72 with good RV myocardial imaging were included. The median age was 57 years; 67 patients (93.1%) were men, and 41 (56,9%) had dilated cardiomyopathy. A receiver-operating characteristic analysis (AUC 0.703, 51.5% sensitivity, 94.9% specificity) was used to identify the optimal cutoff point (0.28%/mmHg) for the RVFWS/TAPSE threshold. Nineteen subjects (26.4%) had advanced RV-PA uncoupling. Event rates were estimated using the Kaplan-Meier method showing a strong association with an increased risk for the primary end point of death or RHF hospitalization (89.47% vs. 30.19%, p < 0.001). A similar observation applied to all-cause mortality (47.37% vs. 13.21%, p = 0.003) and RHF hospitalization (80.43% vs. 20%, p < 0.001).

CONCLUSIONS

An advanced RV dysfunction assessed by RV-PA coupling may serve as a predictor of adverse outcomes in patients with implanted LVADs.

Adverse Hemodynamic Consequences of Continuous Left Ventricular Mechanical Support: JACC Review Topic of the Week

Left ventricular assist devices (LVADs) provide lifesaving therapy for patients with advanced heart failure. The recognition of pump thrombosis, stroke, and nonsurgical bleeding as hemocompatibility-related adverse events (HRAEs) led to pump design improvements and reduced adverse event rates. However, continuous flow can predispose patients to right-sided heart failure (RHF) and aortic insufficiency (AI), especially as patients live longer with their device. Given the hemodynamic contributions to AI and RHF, these comorbidities can be classified as hemodynamic-related events (HDREs). Hemodynamic-driven events are time dependent and often manifest later than HRAEs. This review examines the emerging strategies to mitigate HDREs, with a focus on defining best practices for AI and RHF. As we head into the next generation of LVAD technology, it is important to differentiate HDREs from HRAEs so that we can continue to advance the field and improve the true durability of the pump-patient continuum.

Severe pulmonary valve insufficiency caused by transjugular cannulation of pulmonary artery for right ventricular assist device: diagnosis and surgical solution-a case report

Implantation of a temporary percutaneous right ventricular assist device (RVAD) in patients with right heart failure after left ventricular assist device (LVAD) implantation is an established technique that may cause complications. We present a 60-year-old male patient who underwent urgent LVAD implantation. On the second postoperative day the patient developed acute right heart failure. We implanted a temporary percutaneous RVAD with two cannulas via the right internal jugular vein and the right femoral vein. Transesophageal echocardiography revealed severe pulmonary insufficiency. After performing re-sternotomy we anastomosed a prosthetic graft to the pulmonary trunk (PT), performed subxiphoid tunneling of the graft and replaced the transjugular outflow cannula. The pulmonary regurgitation caused by the percutaneous transvalvular cannula disappeared. In such case a direct anastomosis to the PT is the solution.

Right heart failure after left ventricular assist device implantation: a persistent problem

Left ventricular assist device (LVAD) is an option for bridge-to-transplant or destination therapy for patients with end-stage heart failure. Right heart failure (RHF) remains a complication after LVAD implantation that portends high morbidity and mortality, despite advances in LVAD technology. Definitions of RHF vary, but generally include the need for inotropic or pulmonary vasodilator support, or potential right ventricular (RV) mechanical circulatory support. This review covers the complex pathophysiology of RHF related to underlying myocardial dysfunction, interventricular dependence, and RV afterload, as well as treatment strategies to curtail this challenging problem.

Managing Right Ventricular Failure After Left Ventricular Assist Device Implant at a Destination Therapy Center

Although left ventricular assist device (LVAD) implant is associated with an increased survival in patients with end-stage heart failure, severe right ventricular failure requiring a right ventricular assist device (RVAD) placement is associated with increased short-term morbidity and mortality. Patients not eligible for transplant have limited options, which may impact decision-making and outcomes at nontransplant centers. We conducted a retrospective review of all LVAD implants at our nontransplant center. Primary stratification was by the need for a postoperative RVAD implant. The primary outcome was survival. The Cox proportional hazards regression modeling was used to further evaluate mortality. From 2017 to 2022, 128 patients underwent a primary LVAD implant and 24 (18.75%) required a perioperative RVAD placement. RVAD implant was associated with increased operative mortality (1.92% vs 33.33%, p <0.01) and decreased 1-year (91.29% vs 60.60%, p <0.01) and 2-year survival (84.05% vs 36.36%, p <0.01). However, in patients who survived their index hospitalization, 1-year (93.00% vs 91.67%, p = 0.78) and 2-year (86.16% vs 55.00%, p = 0.10) mortality were similar. On multivariable analysis, the need for a RVAD was associated with an increased hazard of 1-year (5.60 [1.96 to 16.01], p <0.01) and 2-year (5.17 [2.01 to 13.28], p <0.01) mortality. In conclusion, our series from a nontransplant center suggests that patients who survive the implant have acceptable short-term survival, even if they do not have a transplant option; thus, carefully selected patients with biventricular failure may benefit from an LVAD implant, even if an RVAD is needed.

Full-scale numerical simulation of hemodynamics based on left ventricular assist device

Ventricular assist devices have been widely used and accepted to treat patients with end-stage heart failure. The role of VAD is to improve circulatory dysfunction or temporarily maintain the circulatory status of patients. In order to be closer to the medical practice, a multi-Domain model of the left ventricular coupled axial flow artificial heart was considered to study the effect of its hemodynamics on the aorta. Because whether LVAD itself was connected between the left ventricular apex and the ascending aorta by catheter in the loop was not very important for the analysis of simulation results, on the premise of ensuring the multi-Domain simulation, the simulation data of the import and export ends of LVAD were imported to simplify the model. In this paper, the hemodynamic parameters in the ascending aorta, such as blood flow velocity vector, wall shear stress distribution, vorticity current intensity, vorticity flow generation, etc., have been calculated. The numerical conclusion of this study showed the vorticity intensity under LVAD was significantly higher than that under patients' conditions and the overall condition is similar to that of a healthy ventricular spin, which can improve heart failure patients' condition while minimizing other pitfalls. In addition, high velocity blood flow during left ventricular assist surgery is mainly concentrated near the lining of the ascending aorta lumen. What's more, the paper proposes to use Q criterion to determine the generation of vorticity flow. The Q criterion of LVAD is much higher than that of patients with heart failure, and the closer the LVAD is to the wall of the ascending aorta, the greater the Q criterion is. All these are beneficial to the effectiveness of LVAD in the treatment of heart failure patients and provide clinical suggestions for the LVAD implantation in clinical practice.

Preoperative Pulmonary Artery-to-Aorta Diameter Ratio as a Predictor of Postoperative Severe Right Ventricular Failure and 1-Year Mortality After Left Ventricular Assist Device Implantation

OBJECTIVES

To evaluate the association of pulmonary artery diameter and pulmonary artery- to-aorta diameter ratio (PA/Ao) with right ventricular failure and mortality within 1 year after left ventricular assist device implantation.

DESIGN

This was a retrospective observational study between March 2013 and July 2019.

SETTING

The study was conducted at a single, quaternary-care academic center.

PARTICIPANTS

Adults (≥18 years old) receiving a durable left ventricular assist device (LVAD). Inclusion if (1) a chest computed tomography scan was performed within 30 days before the LVAD and (2) a right and left heart catheterization was completed within 30 days before the LVAD.

INTERVENTIONS

A left ventricular assist device was used for intervention.

MEASUREMENTS AND MAIN RESULTS

A total of 176 patients were included in this study. Median PA diameter and PA/Ao ratio were significantly greater in the severe right ventricular failure (RVF) group (p = 0.001, p < 0.001, respectively). Receiver operating characteristic analysis revealed PA/Ao and RVF as predictors for mortality (area under the curve = 0.725 and 0.933, respectively). Logistic regression analysis-predicted probability gave a PA/Ao ratio cutoff point of 1.04 (p < 0.001). Survival probability was significantly worse in patients with a PA/Ao ratio ≥1.04 (p = 0.005).

CONCLUSIONS

The PA/Ao ratio is an easily measurable noninvasive indicator that can predict RVF and 1-year mortality after LVAD implantation.

Management of pregnancy in left ventricular assist device and heart transplant recipients: a concise review

PURPOSE OF REVIEW

Women of reproductive age are increasingly undergoing heart transplantation (HT) or left ventricular assist device (LVAD) implantation for advanced heart failure. This review is intended to give an overview of the current state of the art management of pregnancy in patients with LVAD or HT recipients.

RECENT FINDINGS

Heart transplant recipients are at increased risk for graft rejection, renal dysfunction, preeclampsia and worsening of comorbidities (hypertension and diabetes). Patients with LVAD are at higher risk of thromboembolic events, infections, right ventricular failure and require close surveillance during pregnancy. Preconception counseling must be offered to all women of reproductive age group with HT or LVAD to avoid unplanned pregnancies.

SUMMARY

A multidisciplinary approach with close antepartum and postpartum surveillance is recommended.

Effect of levosimendan infusion prior to left ventricular assist device implantation on right ventricular failure

Objective

Investigate the safety and efficacy of preoperative levosimendan in patients undergoing left ventricular assist device (LVAD) implantation.

Methods

Consecutive patients who received LVADs (HeartMate-2, 3, HVAD) in a single tertiary medical center (2012–2018). INTERMACS profile 1 patients were excluded. The primary outcome was post-LVAD right ventricular failure (RVF) and inhospital mortality rates. The secondary outcomes included other clinical, echocardiographic and hemodynamic parameters at follow-up.

Results

Final cohort consisted of 62 patients (40[65%] in the levosimendan group and 22[35%] in the no-levosimendan group). Post-operative RVF rate and inotrope or ventilation support time were similar in the levosimendan and no-levosimendan groups (7.5% vs. 13.6%; P = 0.43, median of 51 vs. 72 h; P = 0.41 and 24 vs. 27 h; P = 0.19, respectively). Length of hospitalization, both total and in the intensive care unit, was not statistically significant (median days of 13 vs. 16; P = 0.34, and 3 vs. 4; P = 0.44, respectively). Post-operative laboratory and echocardiographic parameters and in-hospital complication rate did not differ between the groups, despite worse baseline clinical parameters in the Levosimendan group. There was no significant difference in the in-hospital and long term mortality rate (2.5% vs. 4.5%; P > 0.999 and 10% vs. 27.3% respectively; P = 0.64).

Conclusions

Levosimendan infusion prior to LVAD implantation was safe and associated with comparable results without significant improved post-operative outcomes, including RVF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01915-6.

Predicting, Recognizing, and Treating Right Heart Failure in Patients Undergoing Durable LVAD Therapy

Despite advancing technology, right heart failure after left ventricular assist device implantation remains a significant source of morbidity and mortality. With the UNOS allocation policy change, a larger proportion of patients proceeding to LVAD are destination therapy and consist of an overall sicker population. Thus, a comprehensive understanding of right heart failure is critical for ensuring the ongoing success of durable LVADs. The purpose of this review is to describe the effect of LVAD implantation on right heart function, review the diagnostic and predictive criteria related to right heart failure, and discuss the current evidence for management and treatment of post-LVAD right heart failure.

Characteristics and Outcomes of Pediatric Patients With a Ventricular Assist Device Presenting to the Emergency Department

OBJECTIVES

A growing number of children receive support from left ventricular assist devices (LVADs) in the outpatient setting. Unexpected complications of LVAD support occur that require emergent management, and no studies examine how pediatric LVAD patients present to the emergency department (ED). The goals of this study were (1) to describe frequency of visits, clinical characteristics, adverse events, and outcomes of LVAD-supported children treated in ED settings and (2) to evaluate for associations between specified patient outcomes and ED care location.

METHODS

This was a retrospective cohort study of children in a single-center outpatient VAD program who presented to several EDs during a 10-year period. We defined adverse events according to the Advanced Cardiac Therapies Improving Outcomes Network registry guidelines. Secondary analysis evaluated for associations between specified patient outcomes (adverse events, hospitalizations, intensive care unit admissions) and ED care location (institutional vs other ED).

RESULTS

Of 104 subjects with LVAD implantations during the study period, 30 (28.8%) transitioned to outpatient care. Among subjects in the outpatient VAD program, 24 (80%) of 30 had 54 visits to various EDs over 141.9 patient-months. The median age at time of ED visit was 13.5 years (range, 7.2-17.9 years). The median number of visits per subject was 1 (range, 0-6). The most common complaints on arrival to the ED were vomiting or abdominal pain (16.7%), fever (15.3%), and headache (13.9%). Seventeen adverse events occurred during 14 (25.9%) of 54 ED visits. The most common adverse events were major infection (33.3%) and right heart failure (16.7%). Hospital admission resulted from 41 (75.9%) of 54 ED visits, including 17 (41.5%) of 41 to a cardiovascular intensive care unit. Care at a nonspecialty ED was associated with a higher rate of hospitalization (93.8% vs 68.4%, P = 0.049). During the study period, 4 subjects (13.3%) died, including 1 patient on destination therapy, 1 with multisystem organ failure due to cardiogenic shock, and 2 with hemorrhagic stroke. No patient died while in the ED.

CONCLUSIONS

Among subjects in a single outpatient pediatric VAD program presenting to the ED, the most common complaints were abdominal pain/vomiting, fever, and headache. The most common adverse events were major infection and right heart failure. Subjects had a high rate of ED utilization and hospital admission.

Physiology and Clinical Utility of HeartMate Pump Parameters

The HeartMate 3 left ventricular assist device (LVAD) is now the only centrifugal pump intended for durable support being actively manufactured and implanted for adults in the United States. The changes in preload and afterload that accompany common clinical scenarios experienced by patients with an LVAD will cause specific changes to the LVAD pump parameters, namely, the pump power, pulsatility index, and flow. Appropriate care of this unique, and growing, population requires a full understanding of these variables as well as the underlying physiologic principles governing their derivation. The aim of this review is to focus on the updated functionality of the HeartMate 3, specifically in comparison to the HeartMate II, as well as the application of pump parameter interpretation to common clinical scenarios.

Continuous-flow left ventricular assist device: Current knowledge, complications, and future directions

Long-term continuous-flow left ventricular assist devices have become a real alternative to heart transplantation in patients with advanced heart failure, achieving a promising 2-year event-free survival rate with new-generation devices. Currently, this technology has spread throughout the world, and any cardiologist or cardiac surgeon should be familiar with its fundamentals and its possible complications as well as the advances made in recent years. The aim of this review is to describe current knowledge, management of complications, and future directions of this novel heart-failure therapy.

Exploring gender differences in trajectories of clinical markers and symptoms after left ventricular assist device implantation

AIMS

Despite well-known gender differences in heart failure, it is unknown if clinical markers and symptoms differ between women and men after left ventricular assist device (LVAD) implantation. Our aim was to examine gender differences in trajectories of clinical markers (echocardiographic markers and plasma biomarkers) and symptoms from pre- to post-LVAD implantation.

METHODS AND RESULTS

This was a secondary analysis of data collected from a study of patients from pre- to 1, 3, and 6 months post-LVAD implantation. Data were collected on left ventricular internal end-diastolic diameter (LVIDd) and ejection fraction (LVEF), plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP), and soluble suppressor of tumorigenicity (sST2). Physical and depressive symptoms were measured using the Heart Failure Somatic Perception Scale and Patient Health Questionnaire-9, respectively. Latent growth curve modelling was used to compare trajectories between women and men. The average age of the sample (n = 98) was 53.3 ± 13.8 years, and most were male (80.6%) and had non-ischaemic aetiology (65.3%). Pre-implantation, women had significantly narrower LVIDd (P < 0.001) and worse physical symptoms (P = 0.041) compared with men. Between pre- and 6 months post-implantation, women had an increase in plasma sST2 followed by a decrease, whereas men had an overall decrease (slope: P = 0.014; quadratic: P = 0.011). Between 1 and 6 months post-implantation, women had a significantly greater increase in LVEF (P = 0.045) but lesser decline in plasmoa NT-proBNP compared with men (P = 0.025).

CONCLUSION

Trajectories of clinical markers differed somewhat between women and men, but trajectories of symptoms were similar, indicating some physiologic but not symptomatic gender differences in response to LVAD.