Incidence and clinical significance of late right heart failure during continuous-flow left ventricular assist device support

Durable left ventricular assist devices as a bridge to transplantation: what to expect along the way?

INTRODUCTION

The scarcity of donors coupled with the improvements in left ventricular assist devices (LVAD) technology has led to the use of LVAD as a bridge to transplantation (BTT).

AREAS COVERED

The authors provide an overview of the current status of LVAD BTT implantation with special focus ranging from patient selection and pre-implantation optimization to post-transplant outcomes.

EXPERT OPINION

The United Network for Organ Sharing 2018 policy amendment resulted in a significant reduction in the number of LVADs used for BTT in the US. To overcome this issue, modifications in the US allocation policy to consider factors such as days on device support, age, and type of complications may be necessary to potentially increase implantation rates.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

The safety of sodium glucose transporter 2 inhibitors and trends in clinical and hemodynamic parameters in patients with left ventricular assist devices

BACKGROUND

The safety and impact of sodium glucose transporter 2 inhibitors (SGLT2-I) in patients with left ventricular assist devices (LVAD) are unknown.

METHODS

A retrospective analysis of all consecutive patients who underwent LVAD Heart Mate 3 (HM3) implantation at a single medical center and received SGLT2-I therapy following surgery was conducted. LVAD parameters, medical therapy, laboratory tests, echocardiography, and right heart catheterization (RHC) study results were recorded and compared before and after initiation of SGLT2-I.

RESULTS

SGLT2-I medications were initiated in 29 (21%) of 138 patients following HM3 implantation (23 (79%) received Empagliflozin and 6 (21%) Dapagliflozin). The mean age at the time of LVAD implantation was 62 ± 6.7 years, 25 (86%) were male, and 23 (79%) had diabetes mellitus. The median time from HM3 implantation to SGLT2-I initiation was 108 days, IQR (26-477). Following SGLT2-I therapy, the daily dose of furosemide decreased from 47 to 23.5 mg/day (mean difference = 23.5 mg/d, 95% CI 8.2-38.7, p = 0.004) and significant weight reduction was observed (mean difference 2.5 kg, 95% CI 0.7-4.3, p = 0.008). Moreover, a significant 5.6 mm Hg reduction in systolic pulmonary artery pressure (sPAP) was measured during RHC (95% CI 0.23-11, p = 0.042) in a subgroup of 11 (38%) patients. LVAD parameters were similar before and after SGLT2-I initiation (p > 0.2 for all). No adverse events were recorded during median follow-up of 354 days, IQR (206-786).

CONCLUSION

SGLT2-I treatment is safe in LVAD patients and might contribute to reduction in patients sPAP.

Hemodynamic Optimization by Invasive Ramp Test in Patients Supported With HeartMate 3 Left Ventricular Assist Device

In patients supported by the HeartMate 3 left ventricular assist device (HM3 LVAD), pump speed adjustments may improve hemodynamics. We investigated the hemodynamic implications of speed adjustments in HM3 recipients undergoing hemodynamic ramp tests. Clinically stable HM3 recipients who underwent routine invasive hemodynamic ramp tests between 2015 and 2022 at our center were included. Filling pressure optimization, defined as central venous pressure (CVP) <12 mm Hg and pulmonary capillary wedge pressure (PCWP) <18 mm Hg, was assessed at baseline and final pump speeds. Patients with optimized pressures were compared to nonoptimized patients. Overall 60 HM3 recipients with a median age of 62 years (56, 71) and time from LVAD implantation of 187 days (124, 476) were included. Optimized filling pressures were found in 35 patients (58%) at baseline speed. Speed was adjusted in 84% of the nonoptimized patients. Consequently, 39 patients (65%) had optimized pressures at final speed. There were no significant differences in hemodynamic findings between baseline and final speeds ( p > 0.05 for all). Six and 12 month readmission-free rates were higher in optimized compared with nonoptimized patients ( p = 0.03 for both), predominantly due to lower cardiac readmission-free rates ( p = 0.052). In stable outpatients supported with HM3 who underwent routine ramp tests, optimized hemodynamics were achieved in only 2 of 3 of the patients. Patients with optimized pressures had lower all-cause readmission rates, primarily driven by fewer cardiac-related hospitalizations.

Right heart failure with left ventricular assist devices: Preoperative, perioperative and postoperative management strategies. A clinical consensus statement of the Heart Failure Association (HFA) of the ESC

Right heart failure (RHF) following implantation of a left ventricular assist device (LVAD) is a common and potentially serious condition with a wide spectrum of clinical presentations with an unfavourable effect on patient outcomes. Clinical scores that predict the occurrence of right ventricular (RV) failure have included multiple clinical, biochemical, imaging and haemodynamic parameters. However, unless the right ventricle is overtly dysfunctional with end-organ involvement, prediction of RHF post-LVAD implantation is, in most cases, difficult and inaccurate. For these reasons optimization of RV function in every patient is a reasonable practice aiming at preparing the right ventricle for a new and challenging haemodynamic environment after LVAD implantation. To this end, the institution of diuretics, inotropes and even temporary mechanical circulatory support may improve RV function, thereby preparing it for a better adaptation post-LVAD implantation. Furthermore, meticulous management of patients during the perioperative and immediate postoperative period should facilitate identification of RV failure refractory to medication. When RHF occurs late during chronic LVAD support, this is associated with worse long-term outcomes. Careful monitoring of RV function and characterization of the origination deficit should therefore continue throughout the patient's entire follow-up. Despite the useful information provided by the echocardiogram with respect to RV function, right heart catheterization frequently offers additional support for the assessment and optimization of RV function in LVAD-supported patients. In any patient candidate for LVAD therapy, evaluation and treatment of RV function and failure should be assessed in a multidimensional and multidisciplinary manner.

"Durable left ventricular assist devices as a bridge to transplantation in The Old and The New World"

Heart transplantation remains the gold standard treatment for end-stage heart failure patients without contraindications. However, limited donor availability and long wait times have created a need for left ventricular assist devices (LVAD) to be used as a bridge to transplantation in appropriately selected patients. Improvements in LVAD technology have resulted in improved short- and long-term outcomes, further supporting the use of these devices for a bridge-to-transplant (BTT) indication. LVAD utilization as BTT exhibits notable disparities worldwide, mainly due to variations in organ availability, allocation policies, and financial constraints. Although Europe has experienced a consistent increase in the use of LVAD for this purpose, the United Network for Organ Sharing 2018 policy amendment resulted in a significant reduction in the number of LVADs used for BTT in the US. To overcome this issue, modifications in the US allocation policy to consider factors such as days on device support, age, and type of complications may be necessary to potentially increase implantation rates.The authors provide an overview comparing the current state of heart transplantation in the US and Europe, with a particular focus on how distinct allocation policies and organ availability impact medical practices. Additionally, the review will examine critical aspects ranging from patient selection and pre-implantation optimization to post-transplant outcomes.

Treatment Strategies and Outcomes of Right Ventricular Failure Post Left Ventricular Assist Device Implantation: An INTERMACS Analysis

Right heart failure (RHF) management after left ventricular assist device (LVAD) implantation includes inotropes, right ventricular mechanical support, and heart transplantation. The purpose of this study is to compare different RHF treatment strategies in patients with a magnetically levitated centrifugal LVAD. A total of 6,632 Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) patients from 2013 to 2020 were included. Of which, 769 (69.6%) patients (group 1) were supported with inotropes (≥14 days post-LVAD implantation), 233 (21.1%) patients (group 2) were supported with temporary right ventricular assist device (RVAD) that was implanted during LVAD implant, 77 (7.0%) patients (group 3) with durable centrifugal RVAD implanted during the LVAD implant, and 26 (2.4%) patients (group 4) were supported with RVAD (temporary or permanent), which was implanted at a later stage. Groups 1 and 4 had higher survival rates in comparison with group 2 (hazard ratio [HR] = 0.513, 95% confidence intervals [CIs] = 0.402-0.655, p < 0.001, versus group 1) and group 3 (HR = 0.461, 95% CIs = 0.320-0.666, p < 0.001, versus group 1). Patients in group 3 showed higher heart transplantation rates at 12 and 36 months as compared with group 1 (40.4% and 46.6% vs. 21.9% and 37.4%, respectively), group 2 (40.4% and 46.6% vs. 25.8% and 39.3%, respectively), and group 4 (40.4% and 46.6% vs. 3.8% and 12.0%, respectively). Severe RHF post-LVAD is associated with poor survival. Patients with LVAD who during the perioperative period are in need of right ventricular temporary or durable mechanical circulatory support constitute a group at particular risk. Improvement of devices tailored for right ventricular support is mandatory for further evolution of the field.

Acute right ventricular geometric change predicts outcomes in HeartMate 3 patients

BACKGROUND

The physiological response of the right ventricle (RV) following left ventricular assist device (LVAD) implantation is difficult to predict. We aimed to investigate RV geometric and functional changes after LVAD insertion and their effects on clinical outcomes.

METHODS

We retrospectively reviewed 188 patients who underwent HeartMate 3 implantation at our center between November 2014 and September 2021. The RV end-diastolic diameter (RVEDD) and RV end-diastolic area (RVEDA) were measured on preoperative and predischarge transthoracic echocardiography. The nonadapted group included patients with increased RVEDD and RVEDA at discharge. The composite outcome was defined as death or readmission due to worsening right heart failure.

RESULTS

There were 82 patients (44%) who had a nonadapted and 106 patients (56%) who had an adapted RV. Preoperatively, the nonadapted group had smaller RVEDD (46 vs 49 mm, p < 0.001) and RVEDA (27 vs 31 cm2, p < 0.001). At discharge, the nonadapted group had larger RVEDD (51 vs 43 mm, p < 0.001) and RVEDA (33 vs 27 cm2, p < 0.001). Kaplan-Meier analysis demonstrated worse 3-year survival (77% vs 91%, p = 0.006) and freedom from composite outcome (58% vs 85%, p < 0.001) in the nonadapted group. A multivariable Cox proportional hazards model showed that nonadaption (hazard ratio [HR] 3.09, 95% confidence interval [CI] 1.29-7.40, p = 0.01) and age (HR 3.73, 95% CI 1.42-9.77, p = 0.007) were independent predictors of composite outcome.

CONCLUSIONS

Acute RV dimensional changes after LVAD insertion may represent intrinsic RV function and may be a useful prognostic marker.

Occult right ventricular dysfunction and right ventricular-vascular uncoupling in left ventricular assist device recipients

BACKGROUND

Detecting right heart failure post left ventricular assist device (LVAD) is challenging. Sensitive pressure-volume loop assessments of right ventricle (RV) contractility may improve our appreciation of post-LVAD RV dysfunction.

METHODS

Thirteen LVAD patients and 20 reference (non-LVAD) subjects underwent comparison of echocardiographic, right heart cath hemodynamic, and pressure-volume loop-derived assessments of RV contractility using end-systolic elastance (Ees), RV afterload by effective arterial elastance (Ea), and RV-pulmonary arterial coupling (ratio of Ees/Ea).

RESULTS

LVAD patients had lower RV Ees (0.20 ± 0.08 vs 0.30 ± 0.15 mm Hg/ml, p = 0.01) and lower RV Ees/Ea (0.37 ± 0.14 vs 1.20 ± 0.54, p < 0.001) versus reference subjects. Low RV Ees correlated with reduced RV septal strain, an indicator of septal contractility, in both the entire cohort (r = 0.68, p = 0.004) as well as the LVAD cohort itself (r = 0.78, p = 0.02). LVAD recipients with low RV Ees/Ea (below the median value) demonstrated more clinical heart failure (71% vs 17%, p = 0.048), driven by an inability to augment RV Ees (0.22 ± 0.11 vs 0.19 ± 0.02 mm Hg/ml, p = 0.95) to accommodate higher RV Ea (0.82 ± 0.38 vs 0.39 ± 0.08 mm Hg/ml, p = 0.002). Pulmonary artery pulsatility index (PAPi) best identified low baseline RV Ees/Ea (≤0.35) in LVAD patients ((area under the curve) AUC = 0.80); during the ramp study, change in PAPi also correlated with change in RV Ees/Ea (r = 0.58, p = 0.04).

CONCLUSIONS

LVAD patients demonstrate occult intrinsic RV dysfunction. In the setting of excess RV afterload, LVAD patients lack the RV contractile reserve to maintain ventriculo-vascular coupling. Depression in RV contractility may be related to LVAD left ventricular unloading, which reduces septal contractility.

The Role of Artificial Intelligence and Machine Learning in the Prediction of Right Heart Failure after Left Ventricular Assist Device Implantation: A Comprehensive Review

One of the most challenging and prevalent side effects of LVAD implantation is that of right heart failure (RHF) that may develop afterwards. The purpose of this study is to review and highlight recent advances in the uses of AI in evaluating RHF after LVAD implantation. The available literature was scanned using certain key words (artificial intelligence, machine learning, left ventricular assist device, prediction of right heart failure after LVAD) was scanned within Pubmed, Web of Science, and Google Scholar databases. Conventional risk scoring systems were also summarized, with their pros and cons being included in the results section of this study in order to provide a useful contrast with AI-based models. There are certain interesting and innovative ML approaches towards RHF prediction among the studies reviewed as well as more straightforward approaches that identified certain important predictive clinical parameters. Despite their accomplishments, the resulting AUC scores were far from ideal for these methods to be considered fully sufficient. The reasons for this include the low number of studies, standardized data availability, and lack of prospective studies. Another topic briefly discussed in this study is that relating to the ethical and legal considerations of using AI-based systems in healthcare. In the end, we believe that it would be beneficial for clinicians to not ignore these developments despite the current research indicating more time is needed for AI-based prediction models to achieve a better performance.

Using pulsatility responses to breath-hold maneuvers to predict readmission rates in continuous-flow left ventricular assist device patients

BACKGROUND

Dynamic respiratory maneuvers induce heterogenous changes to flow-pulsatility in continuous-flow left ventricular assist device patients. We evaluated the association of these pulsatility responses with patient hemodynamics and outcomes.

METHODS

Responses obtained from HVAD (Medtronic) outpatients during successive weekly clinics were categorized into three ordinal groups according to the percentage reduction in flow-waveform pulsatility (peak-trough flow) upon inspiratory-breath-hold, (%∆P): (1) minimal change (%∆P ≤ 50), (2) reduced pulsatility (%∆P > 50 but <100), (3) flatline (%∆P = 100). Same-day echocardiography and right-heart-catheterization were performed. Readmissions were compared between patients with ≥1 flatline response (F-group) and those without (NF-group).

RESULTS

Overall, 712 responses were obtained from 55 patients (82% male, age 56.4 ± 11.5). When compared to minimal change, reduced pulsatility and flatline responses were associated with lower central venous pressure (14.2 vs. 11.4 vs. 9.0 mm Hg, p = 0.08) and pulmonary capillary wedge pressure (19.8 vs. 14.3 vs. 13.0 mm Hg, p = 0.03), lower rates of ≥moderate mitral regurgitation (48% vs. 13% vs. 10%, p = 0.01), lower rates of ≥moderate right ventricular impairment (62% vs. 25% vs. 27%, p = 0.03), and increased rates of aortic valve opening (32% vs. 50% vs. 75%, p = 0.03). The F-group (n = 28) experienced numerically lower all-cause readmissions (1.51 vs. 2.79 events-per-patient-year [EPPY], hazard-ratio [HR] = 0.67, p = 0.12), reduced heart failure readmissions (0.07 vs. 0.57 EPPY, HR = 0.15, p = 0.008), and superior readmission-free survival (HR = 0.47, log-rank p = 0.04). Syncopal readmissions occurred exclusively in the F-group (0.20 vs. 0 EPPY, p = 0.01).

CONCLUSION

Responses to inspiratory-breath-hold predicted hemodynamics and readmission risk. The impact of inspiratory-breath-hold on pulsatility can non-invasively guide hemodynamic management decisions, patient optimization, and readmission risk stratification.

Evolution of Mechanical Circulatory Support for advanced heart failure

This comprehensive review highlights the significant advancements in Left Ventricular Assist Device (LVAD) therapy, emphasizing its evolution from the early pulsatile flow systems to the cutting-edge continuous-flow devices, particularly the HeartMate 3 (HM3) LVAD. These advancements have notably improved survival rates, reduced complications, and enhanced the quality of life (QoL) for patients with advanced heart failure. The dual role of LVADs, as a bridge-to-transplantation and destination therapy is discussed, highlighting the changing trends and policies in their application. The marked reduction in hemocompatibility-related adverse events (HRAE) with the HM3 LVAD, compared to previous models signifies ongoing progress in the field. Challenges such as managing major infections are discussed, including innovative solutions like energy transfer systems aimed at eliminating external drivelines. It explores various LVAD-associated complications, including HRAE, infections, hemodynamic-related adverse events, and cardiac arrhythmias, and underscores emerging strategies for predicting post-implantation outcomes, fostering a more individualized patient care approach. Tools such as the HM3 risk score are introduced for predicting survival based on pre-implant factors, along with advanced imaging techniques for improved complication prediction. Additionally, the review highlights potential new technologies and therapies in LVAD management, such as hemodynamic ramp tests for optimal speed adjustment and advanced remote monitoring systems. The goal is to automate LVAD speed adjustments based on real-time hemodynamic measurements, indicating a shift towards more effective, patient-centered therapy. The review concludes optimistically that ongoing research and potential future innovations hold the promise of revolutionizing heart failure management, paving the way for more effective and personalized treatment modalities.

Should we touch tricuspid valve at the time of LVAD implantation? A young patient series

BACKGROUND

The aim of the study is to compare the results of patients who had moderate or severe tricuspid insufficiency (TI) at the time of left ventricular assist device (LVAD) implantation that did not undergo intervention.

METHODS

Between October 2013 and December 2019, 144 patients who did not undergo tricuspid valve repair (TVR) during LVAD implantation in our department were included in the study. The patients were divided into two groups according to the TI grade; Group 1: 106 patients (73.6%) with moderate TI and Group 2: 38 patients (26.4%) with severe TI. All patients were evaluated for mortality, need of inotrope, blood product transfusion, intensive care unit (ICU) stay, duration of mechanical ventilation, and early and late right ventricular failure (RVF). Minimally invasive technique was favored in patients with worse right ventricular (RV) function to prevent the need for postoperative RV support and bleeding.

RESULTS

The mean ages of the patients in the Group 1 and Group 2 were 46 ± 15 years (82% male), and 45 ± 11.2 years (81.5% males), respectively. Post-operative duration of mechanical ventilation, ICU stay, blood loss, and reoperations were similar (p > 0.05). There was no significant difference in early RVF, pump thrombosis, stroke, bleeding, and 30-day mortality between groups (p > 0.05). Incidence of late RVF was higher in Group 2 (p < 0.05).

CONCLUSION

Although the risk of late RVF may increase in patients with preoperative severe TI, not intervening in TI during LVAD implantation does not cause adverse clinical outcomes in the early period.

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.

Tricuspid regurgitation in the setting of LVAD support

Tricuspid valve regurgitation (TR) is a common complication of end-stage heart failure. Increased pulmonary venous pressures caused by left ventricular (LV) dysfunction can result in a progressive dilation of the right ventricle and tricuspid valve annulus, resulting in functional TR. Here, we review what is known about TR in the setting of severe LV dysfunction necessitating long-term mechanical support with left ventricular assist devices (LVADs), including the occurrence of significant TR, its pathophysiology, and natural history. We examine the impact of uncorrected TR on LVAD outcomes and the impact of tricuspid valve interventions at the time of LVAD placement, revealing that TR frequently improves after LVAD placement with or without concomitant tricuspid valve intervention such that the benefit of concomitant intervention remains controversial. We summarize the current evidence on which to base medical decisions and provide recommendations for future directions of study to address outstanding questions in the field.

Characteristics and Predictors of Late Right Heart Failure After Left Ventricular Assist Device Implantation

Late right heart failure (LRHF) following left ventricular assist device (LVAD) implantation remains poorly characterized and challenging to predict. We performed a multicenter retrospective study of LRHF in 237 consecutive adult LVAD patients, in which LRHF was defined according to the 2020 Mechanical Circulatory Support Academic Research Consortium guidelines. Clinical and hemodynamic variables were assessed pre- and post-implant. Competing-risk regression and Kaplan-Meier survival analysis were used to assess outcomes. LRHF prediction was assessed using multivariable logistic and Cox proportional hazards regression. Among 237 LVAD patients, 45 (19%) developed LRHF at a median of 133 days post-LVAD. LRHF patients had more frequent heart failure hospitalizations ( p < 0.001) alongside other complications. LRHF patients did not experience reduced bridge-to-transplant rates but did suffer increased mortality (hazard ratio 1.95, 95% confidence interval [CI] 1.11-3.42; p = 0.02). Hemodynamically, LRHF patients demonstrated higher right atrial pressure, mean pulmonary arterial pressure, and pulmonary vascular resistance (PVR), but no difference in pulmonary arterial wedge pressure. History of early right heart failure, blood urea nitrogen (BUN) > 35 mg/dl at 1 month post-LVAD, and diuretic requirements at 1 month post-LVAD were each significant, independent predictors of LRHF in multivariable analysis. An LRHF prediction risk score incorporating these variables predicted LRHF with excellent discrimination (log-rank p < 0.0001). Overall, LRHF post-LVAD is more common than generally appreciated, with significant morbidity and mortality. Elevated PVR and precapillary pulmonary pressures may play a role. A risk score using early right heart failure, elevated BUN, and diuretic requirements 1 month post implant predicted the development of LRHF.

Right heart failure after left ventricular assist device: From mechanisms to treatments

Left ventricular assist device (LVAD) therapy is a lifesaving option for patients with medical therapy-refractory advanced heart failure. Depending on the definition, 5-44% of people supported with an LVAD develop right heart failure (RHF), which is associated with worse outcomes. The mechanisms related to RHF include patient, surgical, and hemodynamic factors. Despite significant progress in understanding the roles of these factors and improvements in surgical techniques and LVAD technology, this complication is still a substantial cause of morbidity and mortality among LVAD patients. Additionally, specific medical therapies for this complication still are lacking, leaving cardiac transplantation or supportive management as the only options for LVAD patients who develop RHF. While significant effort has been made to create algorithms aimed at stratifying risk for RHF in patients undergoing LVAD implantation, the predictive value of these algorithms has been limited, especially when attempts at external validation have been undertaken. Perhaps one of the reasons for poor performance in external validation is related to differing definitions of RHF in external cohorts. Additionally, most research in this field has focused on RHF occurring in the early phase (i.e., ≤1 month) post LVAD implantation. However, there is emerging recognition of late-onset RHF (i.e., > 1 month post-surgery) as a significant cause of morbidity and mortality. Late-onset RHF, which likely has a unique physiology and pathogenic mechanisms, remains poorly characterized. In this review of the literature, we will describe the unique right ventricular physiology and changes elicited by LVADs that might cause both early- and late-onset RHF. Finally, we will analyze the currently available treatments for RHF, including mechanical circulatory support options and medical therapies.

Prognostic value of TAPSE/PASP ratio in right ventricular failure after left ventricular assist device implantation: Experience from a tertiary center

Background

In this study, we aimed to investigate the prognostic value of the tricuspid annular plane systolic excursion (TAPSE)/ pulmonary arterial systolic pressure (PASP) ratio in right ventricular failure patients undergoing left ventricular assist device implantation.

Methods

Between February 2013 and February 2020, a total of 75 heart failure patients (65 males, 10 females; median age: 54 years; range, 21 to 66 years) were retrospectively analyzed. The prognostic value of TAPSE/PASP ratio was assessed using the multivariate Cox regression models and confirmed using the Kaplan-Meier analyses.

Results

Forty-one (55.4%) patients had an ischemic heart failure etiology. The indication for assist device implantation was bridge to transplant in 64 (85.3%) patients. The overall survival rates at one, three, and five years following left ventricular assist device implantation were 82.7%, 68%, and 49.3%, respectively. Right ventricular failure was observed in 24 (32%) patients during follow-up. In the multivariate analysis, TAPSE/PASP was found to be independently associated with postoperative right ventricular failure (HR: 1.63; 95% CI: 1.49-2.23). A TAPSE/PASP of 0.34 mm/mmHg was found to be the most accurate predictor value, with lower ratios correlating with right ventricular failure. The Kaplan-Meier analysis showed a better overall survival using a TAPSE/PASP ≥ of 0.34 mm/mmHg (p<0.001).

Conclusion

A lower TAPSE/PASP ratio, particularly lower values than 0.34 mm/mmHg, strongly predicts right ventricular failure after left ventricular assist device implantation in patients with advanced heart failure.

Hospitalization Patterns and Impact of a Magnetically-Levitated Left Ventricular Assist Device in the MOMENTUM 3 Trial

BACKGROUND

In the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) pivotal trial, the HeartMate 3 (HM3) fully magnetically levitated left ventricular assist device (LVAD) demonstrated superiority over the axial-flow HeartMate II (HMII) LVAD. The patterns and predictors of hospitalizations with the HM3 LVAD have not been characterized.

OBJECTIVES

This study sought to determine causes, predictors, and impact of hospitalizations during LVAD support.

METHODS

Patients discharged after LVAD implantation were analyzed. In the pivotal trial, 485 recipients of HM3 were compared with 471 recipients of HMII. The pivotal trial HM3 group was also compared to 949 recipients of HM3 in the postapproval phase within the trial portfolio. Predictors of cause-specific rehospitalization were analyzed.

RESULTS

The rates of rehospitalization were lower with HM3 LVAD than with HMII LVAD in the pivotal trial (225.7 vs 246.4 events per 100 patient-years; P < 0.05). Overall, rehospitalization rates and duration were similar in the HM3 postapproval phase and pivotal trial but prolonged hospitalizations (>7 days) were less frequent (rate ratio: 0.90 [95% CI: 0.80-0.98]; P < 0.05). In HM3 recipients, the most frequent causes of rehospitalization included infection, heart failure (HF)-related events, and bleeding. First rehospitalization caused by HF-related event versus other causes was associated with reduced survival (HR: 2.2 [95% CI: 1.3-3.9]; P = 0.0014). Male sex, non-White race, presence of cardiac resynchronization therapy/implantable cardioverter-defibrillator, obesity, higher right atrial pressure, smaller LV size, longer duration of index hospitalization, and lower estimated glomerular filtration rate at index discharge predicted HF hospitalizations.

CONCLUSIONS

Contemporary support with the HM3 fully magnetically levitated LVAD is associated with a lower hospitalization burden than with prior pumps; however, rehospitalizations for infection, HF, and bleeding remain important challenges for progress in the patient journey. (MOMENTUM 3 IDE Clinical Study, NCT02224755; MOMENTUM 3 Continued Access Protocol [MOMENTUM 3 CAP], NCT02892955).

Right Heart Failure Following Left Ventricular Device Implantation: Natural History, Risk Factors, and Outcomes: An Analysis of the STS INTERMACS Database

BACKGROUND

Our current understanding of right heart failure (RHF) post-left ventricular assist device (LVAD) is lacking. Recently, a new Interagency Registry for Mechanically Assisted Circulatory Support definition of RHF was introduced. Based on this definition, we investigated natural history, risk factors, and outcomes of post-LVAD RHF.

METHODS

Patients implanted with continuous flow LVAD between June 2, 2014, and June 30, 2016 and registered in the Interagency Registry for Mechanically Assisted Circulatory Support/Society of Thoracic Surgeons Database were included. RHF incidence and predictors, and survival after RHF were assessed. The manifestations of RHF which were separately analyzed were elevated central venous pressure, peripheral edema, ascites, and use of inotropes.

RESULTS

Among 5537 LVAD recipients (mean 57±13 years, 49% destination therapy, support 18.9 months) prevalence of 1-month RHF was 24%. Of these, RHF persisted at 12 months in 5.3%. In contrast, de novo RHF, first identified at 3 months, occurred in 5.1% and persisted at 12 months in 17% of these, and at 6 months occurred in 4.8% and persisted at 12 months in 25%. Higher preimplant blood urea nitrogen (ORs,1.03-1.09 per 5 mg/dL increase; P<0.0001), previous tricuspid valve repair/replacement (ORs, 2.01-10.09; P<0.001), severely depressed right ventricular systolic function (ORs,1.17-2.20; P=0.004); and centrifugal versus axial LVAD (ORs,1.15-1.78; P=0.001) represented risk factors for RHC incidence at 3 months. Patients with persistent RHF at 3 months had the lowest 2-year survival (57%) while patients with de novo RHF or RHF which resolved by 3 months had more favorable survival outcomes (75% and 78% at 2 years, respectively; P<0.001).

CONCLUSIONS

RHF at 1 or 3 months post-LVAD was a common and frequently transient condition, which, if resolved, was associated with relatively favorable prognosis. Conversely, de novo, late RHF post-LVAD (>6 months) was more frequently a persistent disorder and associated with increased mortality. The 1-, 3-, and 6-month time points may be used for RHF assessment and risk stratification in LVAD recipients.

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.

Outcomes With Phosphodiesterase-5 Inhibitor Use After Left Ventricular Assist Device: An STS-INTERMACS Analysis

BACKGROUND

Elevated right ventricular afterload following continuous-flow left ventricular assist device (CF-LVAD) may contribute to late right heart failure (LRHF). PDE5i (phosphodiesterase-5 inhibitors) are used to treat pulmonary hypertension and right heart dysfunction after CF-LVAD, but their impact on outcomes is uncertain.

METHODS

We queried Interagency Registry for Mechanically Assisted Circulatory Support from 2012 to 2017 for adults receiving a primary CF-LVAD and surviving ≥30 days from index discharge. Patients receiving early PDE5i (ePDE5i) at 1 month were propensity-matched 1:1 with controls. The primary outcome was the cumulative incidence of LRHF, defined using prevailing Interagency Registry for Mechanically Assisted Circulatory Support criteria; secondary outcomes included all-cause mortality and major bleeding.

RESULTS

Among 9627 CF-LVAD recipients analyzed, 2463 (25.6%) received ePDE5i and 1600 were propensity-matched 1:1 with controls. Before implant, ePDE5i patients had more severe RV dysfunction (13.1% versus 9.6%) and higher pulmonary vascular resistance (2.8±2.7 versus 2.2±2.4 WU), both P<0.001, but clinical factors were well-balanced after propensity-matching. In the unmatched cohort, ePDE5i patients had a higher 3-year cumulative incidence of LRHF, mortality, and major bleeding, but these differences were attenuated in the propensity-matched cohort: LRHF 40.8% versus 35.7% (hazard ratio, 1.14 [95% CI, 0.99-1.32]; P=0.07); mortality 38.6% versus 35.8% (hazard ratio, 0.99 [95% CI, 0.86-1.15]; P=0.93); major bleeding 51.2% versus 46.0% (hazard ratio, 1.12 [95% CI, 0.99-1.27]; P=0.06).

CONCLUSIONS

Compared with propensity-matched controls, adult CF-LVAD patients receiving ePDE5i had similar rates of LRHF, mortality, and major bleeding. While intrinsic patient risk factors likely account for more adverse outcomes with ePDE5i in the unmatched cohort, there is no obvious benefit of ePDE5i in the LVAD population.

The right ventricular involvement in dilated cardiomyopathy: prevalence and prognostic implications of the often-neglected child

Dilated cardiomyopathy (DCM) is a primary heart muscle disease characterized by left or biventricular systolic impairment. Historically, most of the clinical attention has been devoted to the evaluation of left ventricular function and morphology, while right ventricle (RV) has been for many years the forgotten chamber. Recently, progresses in cardiac imaging gave clinicians precious tools for the evaluation of RV, raising the awareness of the importance of biventricular assessment in DCM. Indeed, RV involvement is far from being uncommon in DCM, and the presence of right ventricular dysfunction (RVD) is one of the major negative prognostic determinants in DCM patients. However, some aspects such as the possible role of specific genetic mutations in determining the biventricular phenotype in DCM, or the lack of specific treatments able to primarily counteract RVD, still need research. In this review, we summarized the current knowledge on RV involvement in DCM, giving an overview on the epidemiology and pathogenetic mechanisms implicated in determining RVD. Furthermore, we discussed the imaging techniques to evaluate RV function and the role of RV failure in advanced heart failure.

Contemporary Drug Treatment of Advanced Heart Failure with Reduced Ejection Fraction

The introduction of multiple new pharmacological agents over the past three decades in the field of heart failure with reduced ejection fraction (HFrEF) has led to reduced rates of mortality and hospitalizations, and consequently the prevalence of HFrEF has increased, and up to 10% of patients progress to more advanced stages, characterized by high rates of mortality, hospitalizations, and poor quality of life. Advanced HFrEF patients often show persistent or progressive signs of severe HF symptoms corresponding to New York Heart Association class III or IV despite being on optimal medical, surgical, and device therapies. However, a subpopulation of patients with advanced HF, those with the most advanced stages of disease, were often insufficiently represented in the major trials demonstrating efficacy and tolerability of the drugs used in HFrEF due to exclusion criteria such as low BP and kidney dysfunction. Consequently, the results of many landmark trials cannot necessarily be transferred to patients with the most advanced stages of HFrEF. Thus, the efficacy and tolerability of guideline-directed medical therapies in patients with the most advanced stages of HFrEF often remain unsettled, and this knowledge is of crucial importance in the planning and timing of consideration for referral for advanced therapies. This review discusses the evidence regarding the use of contemporary drugs in the advanced HFrEF population, covering components such as guideline HFrEF drugs, diuretics, inotropes, and the use of HFrEF drugs in LVAD recipients, and provides suggestions on how to manage guideline-directed therapy in this patient group.

Nephrology Considerations in the Management of Durable and Temporary Mechanical Circulatory Support

Durable and temporary mechanical circulatory support (MCS) use is growing for a range of cardiovascular indications. Kidney dysfunction is common in people evaluated for or receiving durable or temporary MCS and portends worse outcomes. This kidney dysfunction can be due to preexisting kidney chronic kidney disease (CKD), acute kidney injury (AKI) related to acute cardiovascular disease necessitating MCS, AKI due to cardiac procedures, and acute and chronic MCS effects and complications. Durable MCS, with implantable continuous flow pumps, is used for long-term support in advanced heart failure refractory to guideline-directed medical and device therapy, either permanently or as a bridge to heart transplantation. Temporary MCS-encompassing in this review intra-aortic balloon pumps (IABP), axial flow pumps, centrifugal flow pumps, and venoarterial ECMO-is used for diverse situations: high-risk percutaneous coronary interventions (PCI), acute decompensated heart failure, cardiogenic shock, and resuscitation after cardiac arrest. The wide adoption of MCS makes it imperative to improve understanding of the effects of MCS on kidney health/function and of kidney health/function on MCS outcomes. The complex structure and functions of the kidney, and the complex health states of individuals receiving MCS, makes investigations in this area challenging, and current knowledge is limited. Fortunately, the increasing nephrology toolbox of noninvasive kidney health/function assessments may enable development and testing of individualized management strategies and therapeutics in the future. We review technology, epidemiology, pathophysiology, clinical considerations, and future directions in MCS and nephrology.

Clinical considerations for the evaluation of patients with left ventricular assist devices

ABSTRACT

A left ventricular assist device (LVAD) provides mechanical circulatory support for patients with end-stage heart failure. As these devices become more prevalent, clinicians must be familiar with the device's function, common complications, and management strategies when evaluating this patient population.

Late-onset right ventricular failure after continuous-flow left ventricular assist device implantation: case presentation and review of the literature

With the widespread use of implantable left ventricular assist device (LVAD), right ventricular failure (RVF) has become a serious problem that becomes apparent several weeks or later after LVAD implantation. However, there are no marked preoperative signs of RVF. This is called late-onset RVF and is currently a major problem leading to long-term complications following implantable LVAD use. Pathogenically, this could be the result of left ventricular suction by LVAD that causes the septum shift to the left ventricular side. This causes a change in morphology of the right ventricle, resulting in impaired right ventricular function. Aortic insufficiency and ventricular arrhythmia, which are also important as long-term complications after LVAD implantation, are considered to be closely involved in the onset and progression of RVF. Once late-onset RVF develops, exercise capacity declines and inotrope administration may be required. Late-onset RVF was also reported to be significantly associated with increased mortality. Several predictors of RVF have been proposed such as preoperative left ventricular diastolic dimension <64 mm, tricuspid valve annulus diameter ≥41 mm, and so on. However, some reports identified no predictors. The basic treatment strategy for late-onset RVF is to optimize volume status by administering diuretics and ensuring inotrope as needed. β-blockers and antiarrhythmic agents often need to be reduced in terms of dosage or even discontinued because these might reduce right ventricular function. Although their efficacy is unclear, pulmonary vasodilators may be used to reduce right ventricular afterload. It is better to decrease the rotation speed of LVAD to minimize the displacement of the septum; however, this is often difficult because the required flow rate cannot be secured. Progress in the prevention and management of late-onset RVF is required because the number of patients who require longer-term LVAD support will increase with the spread of LVAD use as destination therapy.

Invasive Haemodynamic Assessment Before and After Left Ventricular Assist Device Implantation: A Guide to Current Practice

Mechanical circulatory support for the management of advanced heart failure is a rapidly evolving field. The number of durable long-term left ventricular assist device (LVAD) implantations increases each year, either as a bridge to heart transplantation or as a stand-alone ‘destination therapy’ to improve quantity and quality of life for people with end-stage heart failure. Advances in cardiac imaging and non-invasive assessment of cardiac function have resulted in a diminished role for right heart catheterisation (RHC) in general cardiology practice; however, it remains an essential tool in the evaluation of potential LVAD recipients, and in their long-term management. In this review, the authors discuss practical aspects of performing RHC and potential complications. They describe the haemodynamic markers associated with a poor prognosis in patients with left ventricular systolic dysfunction and evaluate the measures of right ventricular (RV) function that predict risk of RV failure following LVAD implantation. They also discuss the value of RHC in the perioperative period; when monitoring for longer term complications; and in the assessment of potential left ventricular recovery.

Evolution of Late Right Heart Failure With Left Ventricular Assist Devices and Association With Outcomes

BACKGROUND

A revised definition of right heart failure (RHF) for the Society of Thoracic Surgeons Intermacs database of left ventricular assist devices (LVADs) was introduced in June 2014.

OBJECTIVES

The purpose of this study was to determine the prevalence and severity of RHF over time and the association of RHF status at 3 months with 12-month outcomes after LVAD.

METHODS

All patients in Society of Thoracic Surgeons Intermacs with follow-up and supported at least 3 months with a continuous flow LVAD implanted between June 2, 2014 and March 31, 2017 without a simultaneous RVAD. RHF was defined as both documentation and manifestations of elevated central venous pressures.

RESULTS

There were 6,118 patients included with an incidence of RHF at 3, 6, and 12 months postimplant categorized as mild in 5%, 6%, and 6% and moderate in 5%, 3%, and 3%, respectively. For those with no RHF at 3 months, there was a low incidence of subsequent RHF at 6 and 12 months. The lack of RHF at 3 months, compared with mild and moderate RHF, was associated with a lower 12-month cumulative incidence of mortality (6.9% vs 16.7% vs 28.1%; P < 0.0001) and a lower 12-month cumulative incidence of stroke (7.4% vs 9.5% vs 11.0%; P = 0.0095), gastrointestinal bleeding (14.8% vs 24.2% vs 23.6%; P < 0.0001), and rehospitalization (65.2% vs 73.2% vs 71.2%; P < 0.0001).

CONCLUSIONS

In patients surviving 3 months with LVAD support alone, mild or moderate RHF occurred in nearly 1 of 10 patients at 12 months. Patients with late RHF had worse survival and a higher cumulative incidence of major adverse events.

Right ventricular failure: a comorbidity or a clinical emergency?

There has been ample data providing a convincing perception about the underlying mechanism pertaining to left ventricle (LV) hypertrophy progressing towards LV failure. In comparison, data available on the feedback of right ventricle (RV) due to volume or pressure overload is minimal. Advanced imaging techniques have aided the study of physiology, anatomy, and diseased state of RV. However, the treatment scenario of right ventricular failure (RVF) demands more attention. It is a critical clinical risk in patients with carcinoid syndrome, pulmonary hypertension, atrial septal defect, and several other concomitant diseases. Although the remodeling responses of both ventricles on an increase of end-diastolic pressure are mostly identical, the stressed RV becomes more prone to oxidative stress activating the apoptotic mechanism with diminished angiogenesis. This instigates the advancement of RV towards failure in contrast to LV. Empirical heart failure (HF) therapies have been ineffective in improving the mortality rate and cardiac function in patients, which prompted a difference between the underlying pathophysiology of RVF and LV failure. Treatment strategies should be devised, taking into consideration the anatomical and physiological characteristics of RV. This review would emphasize on the pathophysiology of the RVF and the differences between two ventricles in molecular response to stress. A proper insight into the underlying pathophysiology is required to develop optimized therapeutic management in RV-specific HF.

Cardiovascular implantable electronic device therapy in patients with left ventricular assist devices: insights from TRAViATA

BACKGROUND

There is conflicting observational data on the survival benefit cardiac implantable electronic devices (CIED) in patients with LVADs.

METHODS

Patients in whom an LVAD was implanted between January 2008 and April 2017 in the multinational Trans-Atlantic Registry on VAD and Transplant (TRAViATA) registry were separated into four groups based on the presence of CIED prior to LVAD implantation: none (n = 146), implantable cardiac defibrillator (ICD) (n = 239), cardiac resynchronization without defibrillator (CRT-P) (n = 28), and CRT with defibrillator (CRT-D) (n = 111).

RESULTS

A total of 524 patients (age 52 years ±12, 84.4% male) were followed for 354 (interquartile range: 166-701) days. After multivariable adjustment, there were no differences in survival across the groups. In comparison to no device, only CRT-D was associated with late right ventricular failure (RVF) (hazard ratio 2.85, 95% confidence interval [CI] 1.42-5.72, p = 0.003). There was no difference in risk of early RVF across the groups or risk of ICD shocks between those with ICD and CRT-D.

CONCLUSION

In a multinational registry of patients with LVADs, there were no differences in survival with respect to CIED subtype. However, patients with a pre-existing CRT-D had a higher likelihood of late RVF suggesting significant long-term morbidity in those with devices capable of LV‑lead pacing post LVAD implantation.

Prognostic Value of Peak Oxygen Uptake in Patients Supported With Left Ventricular Assist Devices (PRO-VAD)

OBJECTIVES

The purpose of this study was to examine whether peak oxygen uptake (pVO₂) and other cardiopulmonary exercise test (CPET)-derived variables could predict intermediate-term mortality in stable continuous flow LVAD recipients.

BACKGROUND

pVO₂ is a cornerstone in the selection of patients for heart transplantation, but the prognostic power of pVO₂ obtained in patients treated with a left ventricular assist device (LVAD) is unknown.

METHODS

We collected data for pVO₂ and outcomes in adult LVAD recipients in a retrospective, multicenter study and evaluated cutoff values for pVO₂ including: 1) values above or below medians; 2) grouping patients in tertiles; and 3) pVO₂ ≤14 ml/kg/min if the patient was not treated with beta-blockers (BB) or pVO₂ ≤12 ml/kg/min if the patient was taking BB therapy.

RESULTS

Nine centers contributed data from 450 patients. Patients were 53 ± 13 years of age; 78% were male; body mass index was 25 ± 5 kg/m² with few comorbidities (stroke: 11%; diabetes: 18%; and peripheral artery disease: 4%). The cause of heart failure (HF) was most often nonischemic (66%). Devices included were the HeartMate II and 3 (Abbott); and Heartware ventricular assist devices Jarvik and Duraheart (Medtronic). The index CPET was performed at a median of 189 days (154 days-225 days) after LVAD implantation, and mean pVO₂ was 14.1 ± 5 ml/kg/min (47% ± 14% of predicted value). Lower pVO₂ values were strongly associated with poorer survival regardless of whether patients were analyzed for absolute pVO₂ in ml/kg/min, pVO₂ ≤12 BB/14 ml/kg/min, or as a percentage of predicted pVO₂ values (P ≤ 0.001 for all). For patients with pVO₂ >12 BB/14 and ventilation/carbon dioxide relationship (VE/VCO₂) slope <35, the 1-year survival was 100%.

CONCLUSIONS

Even after LVAD implantation, pVO₂ has prognostic value, similar to HF patients not supported by mechanical circulatory support devices. (PROgnostic Value of Exercise Capacity Measured as Peak Oxygen Uptake [pVO₂] in Recipients of Left Ventricular Assist Devices [PRO-VAD]; NCT04423562).

Clinical implications of late-onset right ventricular failure after implantation of a continuous-flow left ventricular assist device as bridge to transplantation

OBJECTIVES

The development of late-onset right ventricular failure (LoRVF) that occurs months after a continuous-flow left ventricular assist device (LVAD) is implanted is a clinical problem that warrants investigation. Our goal was to study the incidence, clinical manifestations and prognosis of LoRVF in a population of patients who received an LVAD as bridge to transplantation.

METHODS

Data were analysed from 97 consecutive patients who received an LVAD as bridge to transplantation and underwent a right heart catheterization at least 3 months after receiving an LVAD implantation. LoRVF was defined if both haemodynamic criteria of a central venous pressure >16 mmHg and a cardiac index <2.3 l/min/m2 were present. Clinical and echocardiographic variables, hospitalizations for heart failure and survival were compared between patients with and without LoRVF.

RESULTS

LoRVF was diagnosed in 13% of patients after a median time of 11 months. Patients with LoRVF presented preoperative worse right ventricular (RV) dilatation and severe tricuspid regurgitation. LORVF was also associated with postoperative RV dilatation, moderate to severe tricuspid regurgitation and lower tricuspid annular plane systolic excursion. LoRVF resulted in increased brain natriuretic peptide levels and the need for diuretics, lower haemoglobin levels and a higher rate of atrial fibrillation and gastrointestinal bleeding. The rate of hospitalizations for heart failure in patients with LoRVF was 46%, and 15% required an urgent transplantation due to refractory RV failure. LoRVF decreased global survival and survival free from hospitalizations for heart failure (P < 0.0001).

CONCLUSIONS

LoRVF after the implantation of an LVAD as bridge to transplantation is associated with higher morbidity and lower survival. The results suggest that the routine use of a right heart catheterization and transthoracic echocardiography may contribute to an early diagnosis before further severe complications due to refractory RV failure might occur.

ID NUMBER OF THE IRB APPROVAL

AZ-2019-521 on 10 July 2019.

Clinical findings associated with incomplete hemodynamic left ventricular unloading in patients with a left ventricular assist device

INTRODUCTION AND OBJECTIVES

The effect of a centrifugal continuous-flow left ventricular assist device (cfLVAD) on hemodynamic left ventricular unloading (HLVU) and the clinical conditions that interfere with hemodynamic optimization are not well defined.

METHODS

We retrospectively evaluated the likelihood of incomplete HLVU, defined as high pulmonary capillary wedge pressure (hPCWP)> 15mmHg in 104 ambulatory cfLVAD patients when the current standard recommendations for cfLVAD rotor speed setting were applied. We also evaluated the ability of clinical, hemodynamic and echocardiographic variables to predict hPCWP in ambulatory cfLVAD patients.

RESULTS

Twenty-eight percent of the patients showed hPCWP. The variables associated with a higher risk of hPCWP were age, central venous pressure, absence of treatment with renin-angiotensin-aldosterone system inhibitors, and brain natriuretic peptide levels. Patients with optimal HLVU had a 15.2±14.7% decrease in postoperative indexed left ventricular end-diastolic diameter compared with 8.9±11.8% in the group with hPCWP (P=.041). Independent predictors of hPCWP included brain natriuretic peptide and age. Brain natriuretic peptide <300 pg/mL predicted freedom from hPCWP with a negative predictive value of 86% (P <.0001).

CONCLUSIONS

An optimal HLVU can be achieved in up to 72% of the ambulatory cfLVAD patients when the current standard recommendations for rotor speed setting are applied. Age, central venous pressure and therapy with renin-angiotensin-aldosteron system inhibitors had a substantial effect on achieving this goal. Brain natriuretic peptide levels and the magnitude of reverse left ventricular remodeling seem to be useful noninvasive tools to evaluate HLVU in patients with functioning cfLVAD.

Joint EAPCI/ACVC expert consensus document on percutaneous ventricular assist devices

There has been a significant increase in the use of short-term percutaneous ventricular assist devices (pVADs) as acute circulatory support in cardiogenic shock and to provide haemodynamic support during interventional procedures, including high-risk percutaneous coronary interventions. Although frequently considered together, pVADs differ in their haemodynamic effects, management, indications, insertion techniques, and monitoring requirements. This consensus document summarizes the views of an expert panel by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) and the Association for Acute Cardiovascular Care (ACVC) and appraises the value of short-term pVAD. It reviews the pathophysiological context and possible indications for pVAD in different clinical settings and provides guidance regarding the management of pVAD based on existing evidence and best current practice.

Joint EAPCI/ACVC expert consensus document on percutaneous ventricular assist devices

There has been a significant increase in the use of short-term percutaneous ventricular assist devices (pVADs) as acute circulatory support in cardiogenic shock and to provide haemodynamic support during interventional procedures, including high-risk percutaneous coronary interventions. Although frequently considered together, pVADs differ in their haemodynamic effects, management, indications, insertion techniques, and monitoring requirements. This consensus document summarizes the views of an expert panel by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) and the Association for Acute Cardiovascular Care (ACVC) and appraises the value of short-term pVAD. It reviews the pathophysiological context and possible indications for pVAD in different clinical settings and provides guidance regarding the management of pVAD based on existing evidence and best current practice.

A new hemodynamic index to predict late right failure in patients implanted with last generation centrifugal pump

BACKGROUND

Right ventricular failure (RVF) is a severe event that increases perioperative mortality after left ventricle assist device (LVAD) implantation. Right ventricular (RV) function is particularly affected by the LVAD speed by altering RV preload and afterload as well as the position of the interventricular septum. However, there are no studies focusing on the relationship between pump speed optimization and risk factors for the development of late RVF.

METHODS

Between 2015 and 2019, 50 patients received LVAD implantation at San Camillo Hospital in Rome. Of these, 38 who underwent pump speed optimization were included. Post-optimization hemodynamic data were collected. We assessed a new Hemodynamic Index (HI), calculated as follows:  HI = MAP × PCWP CVP × RPM set RPM max , to determine the risk of late RVF, which was defined as the requirement for rehospitalization and inotropic support.

RESULTS

Ten patients had late RVF after LVAD implantation. Five patients required diuretic therapy and speed optimization. Three patients required inotropic support with adrenaline 0.05 μg/kg/min. Two patients needed prolonged continuous venovenous hemofiltration and high dose inotropic support. Multivariate analysis revealed that a low HI (odds ratio 11.5, 95% confidence interval, 1.85-65.5, p [.003]) was an independent risk factor for late RVF after LVAD implantation.

CONCLUSION

We demonstrated a low HI being a significant risk factor for the development of RVF after LVAD implantation. We suggest implementing HI as a decision support tool for goal-direct optimization of the device aiming to reduce the burden of late-onset RVF during the follow-up.

Pulmonary vasodilator use in continuous-flow left ventricular assist device management

Pulmonary hypertension (PH) due to left heart disease is the most common etiology for PH. PH in patients with heart failure with reduced fraction (HFrEF) is associated with reduced functional capacity and increased mortality. PH-HFrEF can be isolated post-capillary or combined pre- and post-capillary PH. Chronic elevation of left-sided filling pressures may lead to reverse remodeling of the pulmonary vasculature with development of precapillary component of PH. Untreated PH in patients with HFrEF results in predominant right heart failure (RHF) with irreversible end-organ dysfunction. Management of PH-HFrEF includes diuretics, vasodilators like angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers or angiotensin-receptor blocker-neprilysin inhibitors, hydralazine and nitrates. There is no role for pulmonary vasodilator use in patients with PH-HFrEF due to increased mortality in clinical trials. In patients with end-stage HFrEF and fixed PH unresponsive to vasodilator challenge, implantation of continuous-flow left ventricular assist device (cfLVAD) results in marked improvement in pulmonary artery pressures within 6 months due to left ventricular (LV) mechanical unloading. The role of pulmonary vasodilators in management of precapillary component of PH after cfLVAD is not well-defined. The purpose of this review is to discuss the pharmacologic management of PH after cfLVAD implantation.

Perioperative Right Ventricular Dysfunction: Analysis of Outcomes

Right ventricular dysfunction (RVD) is a well-known prognostic factor for adverse outcomes in cardiovascular medicine. The right ventricle (RV) in medically managed heart failure patients and in surgical patients perioperatively generally is overshadowed by left ventricular disease. However, with advancement of various diagnostic tools and better understanding of its functional anatomy, the role of the RV is emerging in many clinical conditions. The failure of one ventricle has significant effect on the function of the other ventricle and it is predominantly due to ventricular interdependence.¹ The etiology of RVD is multifactorial and irrespective of etiology. RVD has been associated with significant increases in morbidity and mortality in various clinical scenarios.^2,3 The primary objective of this comprehensive review is to analyze various etiology-related outcomes of RVD in the perioperative population.

Right Ventricular Failure Post-Implantation of Left Ventricular Assist Device: Prevalence, Pathophysiology, and Predictors

Despite advances in left ventricular assist device (LVAD) technology, right ventricular failure (RVF) continues to be a complication after implantation. Most patients undergoing LVAD implantation have underlying right ventricular (RV) dysfunction (either as a result of prolonged LV failure or systemic disorders) that becomes decompensated post-implantation. Additional insults include intra-operative factors or a sudden increase in preload in the setting of increased cardiac output. The current literature estimates post-LVAD RVF from 3.9% to 53% using a diverse set of definitions. A few of the risk factors that have been identified include markers of cardiogenic shock (e.g., dependence on inotropes and Interagency Registry for Mechanically Assisted Circulatory Support profiles) as well as evidence of cardiorenal or cardiohepatic syndromes. Several studies have devised multivariable risk scores; however, their performance has been limited. A new functional assessment of RVF and a novel hepatic marker that describe cholestatic properties of congestive hepatopathy may provide additional predictive value. Furthermore, future studies can help better understand the relationship between pulmonary hypertension and post-LVAD RVF. To achieve our ultimate goal-to prevent and effectively manage RVF post-LVAD-we must start with a better understanding of the risk factors and pathophysiology. Future research on the different etiologies of RVF-ranging from acute post-surgical complication to late-onset RV cardiomyopathy-will help standardize definitions and tailor therapies appropriately.

Influence of Atrial Fibrillation on Functional Tricuspid Regurgitation in Patients With HeartMate 3

Background

Functional tricuspid regurgitation (TR) can occur secondary to atrial fibrillation (AF). The impact of AF on functional TR and cardiovascular events is uncertain in patients with left ventricular assist devices. This study aimed to investigate the effect of AF on functional TR and cardiovascular events in patients with a HeartMate 3 left ventricular assist device.

Methods and Results

We retrospectively reviewed 133 patients who underwent HeartMate 3 implantation at our center between November 2014 and November 2018. We excluded patients who had undergone previous or concomitant tricuspid valve procedures and those whose echocardiographic images were of insufficient quality. The primary end point was death and the presence of a cardiovascular event at 1 year. We defined cardiovascular event as a composite of death, stroke, and hospital readmission due to recurrent heart failure and significant residual TR as vena contracta width ≥3 mm. In total, 110 patients were included in this analysis. Patients were divided into 3 groups: no AF (n=51), paroxysmal AF (n=40), and persistent AF (PeAF) (n=19). Kaplan‐Meier analysis showed that patients with PeAF had the worst survival (no AF 98%, paroxysmal AF 98%, PeAF 84%, log‐rank P=0.038) and event‐free rate (no AF 93%, paroxysmal AF 89%, PeAF 72%, log‐rank P=0.048) at 1 year. Thirty‐one (28%) patients had residual TR 1 month after left ventricular assist device implantation. Patients with residual TR had a significantly poor prognosis compared with those without residual TR (log‐rank P=0.014).

Conclusions

PeAF was associated with increased mortality, cardiovascular events, and residual TR compared with no AF and paroxysmal AF.

Discharge and Readmissions After Ventricular Assist Device Placement in the US Pediatric Hospitals: A Collaboration in ACTION

Discharging children on ventricular assist device (VAD) support offers advantages for quality of life. We sought to describe discharge and readmission frequency in children on VAD support. All VAD-implanted patients aged 10-21 years at Advanced Cardiac Therapies Improving Outcomes Network (ACTION) centers were identified from the Pediatric Health Information System database (2009-2018). Discharge frequency on VAD was calculated. Patients discharged on VAD were compared with those not discharged. Freedom from readmission was assessed using the Kaplan-Meier method. A total of 298 VAD-implanted patients from 25 centers were identified, of which 163 (54.7%) were discharged. Discharges increased over time (36.9% [2009-2012] vs. 59.7% [2013-2018], p = 0.001). Of 144 discharged patients with follow-up, 96 (66.7%) were readmitted for reasons other than transplantation. Heart failure was the most common reason for readmission (27.7%), followed by infection (25.8%) and hematologic concerns (16.8%). In-hospital mortality on readmission was uncommon (1.8%) and the median length of stay was 6 days (interquartile range 2-19 days). Discharge of children on VAD support has increased over time, although variability exists across centers. Readmissions are common with diverse indications; however, the risk of mortality is low. Further interventions, including collaboration in ACTION, are critical to increasing discharges and optimizing outpatient management.

Short-Term Efficacy and Safety of Tolvaptan in Patients with Left Ventricular Assist Devices

Tolvaptan is an effective therapy for heart failure patients with symptomatic congestion and hyponatremia. The efficacy of its use in patients with continuous-flow left ventricular assist devices (LVADs) is unknown. The aim of this study was to assess the clinical efficacy and safety of tolvaptan in LVAD patients. We retrospectively reviewed medical records of patients who underwent LVAD implantation between January 2014 and August 2018. Among 217 consecutive LVAD patients, tolvaptan was used in 20 patients. Mean age was 46 ± 14 years old and 14 patients were males. The duration of tolvaptan therapy was 4 (interquartile range 1-8) days. Urine volume significantly increased from 2,623 ± 1,109 ml/day before tolvaptan to 4,308 ± 1,432 ml/day during tolvaptan therapy (p < 0.001). Serum sodium increased from 127 ± 3 to 133 ± 3 mEq/L at the end of tolvaptan therapy (p < 0.001). No patients developed hypernatremia (serum sodium >150 mEq/L). The 90-day overall survival following tolvaptan therapy was 89% in both the tolvaptan group and a propensity score-matched non-tolvaptan group (p = 0.918). Survival free of heart failure readmissions was also comparable between the groups (p = 0.751). In conclusion, short-term use of tolvaptan following LVAD implantation is a safe and effective therapy to augment diuresis and improve hyponatremia.

Consequences of functional mitral regurgitation and atrial fibrillation in patients with left ventricular assist devices

BACKGROUND

Functional mitral regurgitation (MR) (FMR) and atrial fibrillation (AF) are common in patients undergoing left ventricular assist device (LVAD) implantation. However, the impact of FMR and AF on clinical outcomes is uncertain. This study aimed to investigate the characteristics and prognostic significance of FMR and AF in patients with LVADs.

METHODS

We retrospectively reviewed all patients who underwent LVAD implantation at our center between January 2010 and December 2017. We defined significant FMR as the ratio of MR color jet area to left atrial area of >20% and persistent or permanent AF (PeAF) as persistent or permanent AF at LVAD implantation.

RESULTS

A total of 380 patients were included in this analysis. Patients were divided into 6 groups: patients with no PeAF and no significant FMR (Group 1), patients with no PeAF but with significant FMR (Group 2), patients with PeAF but no significant FMR (Group 3), patients with PeAF and significant FMR (Group 4), patients with concomitant mitral valve surgery (MVS) at LVAD implantation and without PeAF (Group 5), and patients with concomitant MVS and with PeAF (Group 6). A total of 56 patients (15%) died within 2 years. Kaplan-Meier curve analysis demonstrated a 2-year survival of 81% in Group 1, 89% in Group 2, 87% in Group 3, 47% in Group 4, 87% in Group 5, and 79 % in Group 6 (log-rank test, p < 0.001). The multivariable Cox proportional-hazards model showed that classification in Group 4 was an independent predictor of mortality (hazard ratio, 4.31; 95% CI: 2.19-8.46; p < 0.001).

CONCLUSIONS

The coexistence of significant FMR and PeAF may represent a poor prognostic marker in patients undergoing LVAD implantation.