Tricuspid Incompetence and Geometry of the Right Ventricle as Predictors of Right Ventricular Function After Implantation of a Left Ventricular Assist Device

The Right Ventricular-Arterial Compliance Index: A Novel Hemodynamic Marker to Predict Right Heart Failure Following Left Ventricular Assist Device

The development of right heart failure (RHF) in patients with advanced heart failure following left ventricular assist device (LVAD) implantation remains difficult to predict. We proposed a novel composite hemodynamic index-the right ventricular-arterial compliance index (RVACi), derived from pulmonary artery pulse pressure (PAPP), ejection time (ET), heart rate (HR), and cardiac output (CO), with and expressed as mm Hg·s/L. We then conducted a retrospective, single-center analysis comparing the predictive value of RVACi for the development of RHF or unplanned right ventricular (RV) mechanical circulatory support following LVAD implantation against existing hemodynamic indices. One hundred patients were enrolled after screening 232 patients over a 10 year period, with 74 patients having complete hemodynamic data for RVACi calculation. There was good correlation between pulmonary arterial capacitance ( R ² = 0.48) and pulmonary vascular resistance ( R ² = 0.63) with RVACi, but not RV stroke work index or pulmonary artery pulsatility index. Reduced baseline RVACi (52 ± 23 vs . 92 ± 55 mm Hg·s/L; p = 0.02) was the strongest hemodynamic predictor of unplanned RV mechanical circulatory support requirement in patients following LVAD insertion. Composite pulsatile hemodynamic indices including RVACi may provide additional insight over existing hemodynamic indices for the prediction of RHF and need for RV mechanical circulatory support.

Tricuspid Valve Reconstruction in Patients with Right Heart Decompensation Due to Severe Tricuspid Regurgitation on LVAD Support

Background/Objectives: Right ventricular (RV) dysfunction after left ventricular assist device (LVAD) implantation is associated with reduced survival and affects duration of hospitalization. Some patients with RV dysfunction on LVAD have significant tricuspid valve regurgitation (TR) with concomitant signs of RV failure. In these cases, tricuspid valve repair (TVR) may minimize clinical signs of RV failure. Methods: We report on two patients (one female, one male) developing significant TR receiving TVR through a right thoracotomy on LVAD support. Results: The time between LVAD implantation and TVR was 4 months and 50 months, respectively. The female patient could be discharged from hospital without TR and any signs of RV dysfunction. The male patient died 13 days later due to septic shock following mesenteric ischemia. At this time, echocardiography showed a competent tricuspid valve. Conclusions: In conclusion, these results provide insight into the clinical judgment of when TVR should be attempted. They suggest whether TVR may be a strategy to avoid hospitalization, minimize the clinical signs of RV insufficiency and improve quality of life in patients on LVAD support with severe TR and clinical signs of right heart dysfunction.

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.

Surgical Treatment of Tricuspid Valve Regurgitation in Patients Undergoing Left Ventricular Assist Device Implantation: Interim analysis of the TVVAD trial

OBJECTIVES

Right heart failure remains a serious complication of left ventricular assist device therapy. Many patients presenting for left ventricular assist device implantation have significant tricuspid regurgitation. It remains unknown whether concurrent tricuspid valve surgery reduces postoperative right heart failure. The primary aim was to identify whether concurrent tricuspid valve surgery reduced the incidence of moderate or severe right heart failure within the first 6 months after left ventricular assist device implantation.

METHODS

Patients with moderate or severe tricuspid regurgitation on preoperative echocardiography were randomized to left ventricular assist device implantation alone (no tricuspid valve surgery) or with concurrent tricuspid valve surgery. Randomization was stratified by preoperative right ventricular dysfunction. The primary end point was the frequency of moderate or severe right heart failure within 6 months after surgery.

RESULTS

This report describes a planned interim analysis of the first 60 randomized patients. The tricuspid valve surgery group (n = 32) had mild or no tricuspid regurgitation more frequently on follow-up echocardiography studies compared with the no tricuspid valve surgery group (n = 28). However, at 6 months, the incidence of moderate and severe right heart failure was similar in each group (tricuspid valve surgery: 46.9% vs no tricuspid valve surgery: 50%, P = .81). There was no significant difference in postoperative mortality or requirement for right ventricular assist device between the groups. There were also no significant differences in secondary end points of functional status and adverse events.

CONCLUSIONS

The presence of significant tricuspid regurgitation before left ventricular assist device is associated with a high incidence of right heart failure within the first 6 months after surgery. Tricuspid valve surgery was successful in reducing postimplant tricuspid regurgitation compared with no tricuspid valve surgery but was not associated with a lower incidence of right heart failure.

Special Considerations for Advanced Heart Failure Surgeries: Durable Left Ventricular Devices and Heart Transplantation

Heart transplantation and durable left ventricular assist devices (LVADs) represent two definitive therapies for end-stage heart failure in the modern era. Despite technological advances, both treatment modalities continue to experience unique risks that impact surgical and perioperative decision-making. Here, we review special populations and factors that impact risk in LVAD and heart transplant surgery and examine critical decisions in the management of these patients. As both heart transplantation and the use of durable LVADs as destination therapy continue to increase, these considerations will be of increasing relevance in managing advanced heart failure and improving outcomes.

Machine Learning Multicenter Risk Model to Predict Right Ventricular Failure After Mechanical Circulatory Support: The STOP-RVF Score

Importance

The existing models predicting right ventricular failure (RVF) after durable left ventricular assist device (LVAD) support might be limited, partly due to lack of external validation, marginal predictive power, and absence of intraoperative characteristics.

Objective

To derive and validate a risk model to predict RVF after LVAD implantation.

Design, Setting, and Participants

This was a hybrid prospective-retrospective multicenter cohort study conducted from April 2008 to July 2019 of patients with advanced heart failure (HF) requiring continuous-flow LVAD. The derivation cohort included patients enrolled at 5 institutions. The external validation cohort included patients enrolled at a sixth institution within the same period. Study data were analyzed October 2022 to August 2023.

Exposures

Study participants underwent chronic continuous-flow LVAD support.

Main Outcome and Measures

The primary outcome was RVF incidence, defined as the need for RV assist device or intravenous inotropes for greater than 14 days. Bootstrap imputation and adaptive least absolute shrinkage and selection operator variable selection techniques were used to derive a predictive model. An RVF risk calculator (STOP-RVF) was then developed and subsequently externally validated, which can provide personalized quantification of the risk for LVAD candidates. Its predictive accuracy was compared with previously published RVF scores.

Results

The derivation cohort included 798 patients (mean [SE] age, 56.1 [13.2] years; 668 male [83.7%]). The external validation cohort included 327 patients. RVF developed in 193 of 798 patients (24.2%) in the derivation cohort and 107 of 327 patients (32.7%) in the validation cohort. Preimplant variables associated with postoperative RVF included nonischemic cardiomyopathy, intra-aortic balloon pump, microaxial percutaneous left ventricular assist device/venoarterial extracorporeal membrane oxygenation, LVAD configuration, Interagency Registry for Mechanically Assisted Circulatory Support profiles 1 to 2, right atrial/pulmonary capillary wedge pressure ratio, use of angiotensin-converting enzyme inhibitors, platelet count, and serum sodium, albumin, and creatinine levels. Inclusion of intraoperative characteristics did not improve model performance. The calculator achieved a C statistic of 0.75 (95% CI, 0.71-0.79) in the derivation cohort and 0.73 (95% CI, 0.67-0.80) in the validation cohort. Cumulative survival was higher in patients composing the low-risk group (estimated <20% RVF risk) compared with those in the higher-risk groups. The STOP-RVF risk calculator exhibited a significantly better performance than commonly used risk scores proposed by Kormos et al (C statistic, 0.58; 95% CI, 0.53-0.63) and Drakos et al (C statistic, 0.62; 95% CI, 0.57-0.67).

Conclusions and Relevance

Implementing routine clinical data, this multicenter cohort study derived and validated the STOP-RVF calculator as a personalized risk assessment tool for the prediction of RVF and RVF-associated all-cause mortality.

Successful echocardiography-guided medical management of severe early post-implant right ventricular failure in a patient with left ventricular assist device support: a case report

BACKGROUND

Post-implant right heart failure (RHF) has been recognized as a crucial prognostic factor in patients receiving left ventricular assist devices (LVADs), and its management has long attracted attention from cardiologists and surgeons.

CASE PRESENTATION

This report described an 18-year-old female with acutely deteriorating heart failure due to dilated cardiomyopathy who underwent paracorporeal pulsatile-flow LVAD and developed early post-implant RHF. At postoperative day (POD) six, she was almost asymptomatic at rest on 2.5 mg/kg/min of dobutamine; however, the echocardiogram, performed as part of the daily postoperative care, revealed a severely enlarged right ventricle with a decompressed left ventricle, implying the development of post-implant RHF. Bolus infusion of saline and reduction of pump flow (6.0 L/min to 3.0 L/min) led to normalization of both ventricular shapes in 30 s, suggesting that RHF could be managed without surgical interventions. Milrinone was started on POD six, followed by sildenafil administration on POD seven. Fluid balance was strictly adjusted under the close observation of daily echocardiograms. Milrinone and dobutamine were discontinued on PODs 18 and 21, respectively. The patient was listed for a heart transplant on POD 40. Despite reduced right ventricular function (right ventricular stroke work index of 182.34 mmHg*ml/m- 2, body surface area 1.5 m2), she was successfully converted to implantable LVAD on POD 44 with no recurrence of post-implant RHF thereafter for four years.

CONCLUSIONS

In post-implant RHF management, early detection, together with proper and prompt medical management, is crucial to avoiding any surgical intervention. Close observation of daily echocardiograms might be helpful in detecting subclinical RHF and is useful for post-implant medical management.

Proportion of right ventricular failure and echocardiographic predictors in continuous-flow left ventricular assist device: a systematic review and meta-analysis

Background

Right ventricular failure (RVF) in patients with a continuous-flow left ventricle assist device (CF-LVAD) is associated with higher incidence of mortality. This systematic review aims to assess the overall proportion of RVF and the pre-operative echocardiographic parameters which are best correlating to RVF.

Methods

A systematic research was conducted between 2008 and 2019 on MEDLINE, EMBASE, PUBMED, UPTODATE, OVID, COCHRANE LIBRARY, and Google Scholar electronic databases by performing a PRISMA flowchart. All observational studies regarding echocardiographic predictors of RVF in patients undergoing CF-LVAD implantation were included.

Results

A total number of 19 observational human studies published between 2008 and 2019 were included. We identified 524 RVF patients out of a pooled final population of 1741 patients. The RVF overall proportion was 28.25% with 95% confidence interval (CI) 0.24-0.34. The highest variability of perioperative echocardiographic parameters between the RVF and no right ventricular failure (NO-RVF) groups has been found with tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and right ventricular global longitudinal strain (RVGLS). Their standardized mean deviation (SMD) was - 0.33 (95% CI - 0.54 to - 0.11; p value 0.003), - 0.34 (95% CI - 0.53 to - 0.15; p value 0.0001), and 0.52 (95% CI 0.79 to 0.25; p value 0.0001), respectively.

Conclusions

The echocardiographic predictors of RVF after CF-LVAD placement are still uncertain. However, there seems to be a trend of statistical correlation between TAPSE, FAC, and RVGLS with RVF event after CF-LVAD placement.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-022-01447-7.

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.

Blood flow kinetic energy is a novel marker for right ventricular global systolic function in patients with left ventricular assist device therapy

Objectives

Right ventricular (RV) failure remains a major concern in heart failure (HF) patients undergoing left ventricular assist device (LVAD) implantation. We aimed to measure the kinetic energy of blood in the RV outflow tract (KE-RVOT) - a new marker of RV global systolic function. We also aimed to assess the relationship of KE-RVOT to other echocardiographic parameters in all subjects and assess the relationship of KE-RVOT to hemodynamic parameters of RV performance in HF patients.

Methods

Fifty-one subjects were prospectively enrolled into 4 groups (healthy controls, NYHA Class II, NYHA Class IV, LVAD patients) as follows: 11 healthy controls, 32 HF patients (8 NYHA Class II and 24 Class IV), and 8 patients with preexisting LVADs. The 24 Class IV HF patients included 21 pre-LVAD and 3 pre-transplant patients. Echocardiographic parameters of RV function (TAPSE, St', Et', IVA, MPI) and RV outflow color-Doppler images were recorded in all patients. Invasive hemodynamic parameters of RV function were collected in all Class IV HF patients. KE-RVOT was derived from color-Doppler imaging using a vector flow mapping proprietary software. Kruskal-Wallis test was performed for comparison of KE-RVOT in each group. Correlation between KE-RVOT and echocardiographic/hemodynamic parameters was assessed by linear regression analysis. Receiver operating characteristic curves for the ability of KE-RVOT to predict early phase RV failure were generated.

Results

KE-RVOT (median ± IQR) was higher in healthy controls (55.10 [39.70 to 76.43] mW/m) than in the Class II HF group (22.23 [15.41 to 35.58] mW/m, p < 0.005). KE-RVOT was further reduced in the Class IV HF group (9.02 [5.33 to 11.94] mW/m, p < 0.05). KE-RVOT was lower in the LVAD group (25.03 [9.88 to 38.98] mW/m) than the healthy controls group (p < 0.005). KE-RVOT had significant correlation with all echocardiographic parameters and no correlation with invasive hemodynamic parameters. RV failure occurred in 12 patients who underwent LVAD implantation in the Class IV HF group (1 patient was not eligible due to death immediately after the LVAD implantation). KE-RVOT cut-off value for prediction of RV failure was 9.15 mW/m (sensitivity: 0.67, specificity: 0.75, AUC: 0.66).

Conclusions

KE-RVOT, a novel noninvasive measure of RV function, strongly correlates with well-established echocardiographic markers of RV performance. KE-RVOT is the energy generated by RV wall contraction. Therefore, KE-RVOT may reflect global RV function. The utility of KE-RVOT in prediction of RV failure post LVAD implantation requires further study.

Interventricular-Septal Output While Supported on Left Ventricular Assist Device Therapy

The effects of left ventricular unloading on septal function in patients with left ventricular assist devices (LVADs) have not been well characterized in vivo. The purpose of this study was to evaluate the relationship between markers of septal function with echocardiography in relationship to RV dysfunction and late RV failure after LVAD implantation. A retrospective study was conducted of patients supported on centrifugal-flow LVADs implanted over a 10-year period. Echocardiographic data were collected pre-operatively and up to 2 years after implantation. Interventricular septum (IVS) measurements were taken at end-systole and end-diastole. Interventricular-septal output (ISO) was calculated using the formula: (IVSs-IVSd)×heart rate. A total of 110 patients were included. An immediate and sustained reduction in both lateral annulus systolic velocity (RVS') and TAPSE were observed after implant ( p < 0.0001). However, ISO gradually decreased over time ( p < 0.0001). While ISO was not predictive of late RV failure, a decrease in ISO by 25% or greater from pre-implant to hospital discharge was associated with late RV failure (OR 4.8; 95% CI, 1.4-16.5; p = 0.012) even after adjusting for relevant clinical variables ( p ≤ 0.01 for each model). RV function is known to be influenced by mechanical ventricular interdependence and we demonstrate that measurement of ISO may be a useful marker in assessing RV dysfunction and predicting RV failure in patients following LVAD implantation.

Concomitant tricuspid valve repair in left ventricular assist device implantation may increase the risk for temporary right ventricular support but does not impact overall outcomes

OBJECTIVES

Tricuspid valve repair in left ventricular assist device implantation continues to pose a challenge and may impact the occurrence of early and late right heart failure. We investigated the effects of concomitant tricuspid repair on clinical outcomes.

METHODS

A retrospective, multicentre study enrolled adult patients who received continuous-flow left ventricular assist devices between 2005 and 2017 and compared those who received concomitant tricuspid valve repair to those who did not. Primary outcomes were early right heart failure necessitating temporary ventricular assist devices and right heart failure-related rehospitalizations requiring inotropic or diuretic treatment.

RESULTS

Out of 526 patients who underwent left ventricular assist device implantation, 110 (21%) received a concomitant tricuspid valve repair. Those patients were sicker, and most had moderate or severe tricuspid regurgitation. A significantly higher incidence of temporary right ventricular assist devices was observed in the group with concomitant tricupid valve repair (18% vs. 11%, P = 0.049), with a significantly elevated risk for temporary right heart assist device (sHR 1.68, 95% CI 1.04-2.72; P = 0.037). After adjusting for confounders, no significant differences were found in the incidence of and risk for most clinical outcomes, including right heart failure-related rehospitalizations (P = 0.891) and death (P = 0.563).

CONCLUSIONS

Concomitant tricuspid valve repair, when deemed necessary in left ventricular assist device implantation, may increase the risk of early right heart failure requiring a temporary right ventricular assist device but does not impact the incidence or risk of death or rehospitalizations due to late right heart failure.

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.

Tricuspid Valve Surgery in Patients Receiving Left Ventricular Assist Devices

BACKGROUND

 Tricuspid regurgitation (TR) is common and related to poor prognosis in patients after left ventricular assist device (LVAD) implantation. The concomitant tricuspid valve surgery (TVS) at the time of LVAD implantation on short and long-term outcomes are controversial in current evidence.

METHODS

 This is a single-center, observational, retrospective study. We enrolled patients with moderate-to-severe TR who received LVAD implantations from 2009 to 2020. Postoperative right ventricular failure (RVF), right ventricular assist device (RVAD) use, hospital mortality, new-onset renal replacement therapy (RRT), and acute kidney injury (AKI) were evaluated retrospectively.

RESULTS

 Sixty-eight patients were included, 36 with and 32 without concomitant TVS. Baseline characteristics did not differ between the two groups. Patients receiving TVS had significantly increased incidences of postoperative RVF (52.8 vs. 25.0%, p = 0.019), RVAD implantation (41.7 vs. 18.8%, p = 0.041), and new-onset RRT (22.2 vs. 0%, p = 0.004). No difference in the incidence of AKI and hospital mortality was detected. Besides, these associations remained consistent in patients who underwent LVAD implantation via median sternotomy. During a median follow-up of 2.76 years, Kaplan-Meier analysis and competing-risk analysis showed that TVS was not associated with better overall survival in patients after LVAD implantation compared with the no-TVS group.

CONCLUSION

 Our study suggests that concomitant TVS failed to show benefits in patients receiving LVAD implantation. Even worse, concomitant TVS is associated with significantly increased incidences of RVF, RVAD use, and new-onset of RRT. Considering the small sample size and short follow-up, these findings warrant further study.

Prognostic Value of Natriuretic Peptides for All-Cause Mortality, Right Ventricular Failure, Major Adverse Events, and Myocardial Recovery in Advanced Heart Failure Patients Receiving a Left Ventricular Assist Device: A Systematic Review

Aims: Major adverse event (MAE) rates during left ventricular assist device (LVAD) therapy in advanced heart failure (HF) patients are high, and impair quality of life and survival. Prediction and risk stratification of MAEs in order to improve patient selection and thereby outcome during LVAD therapy is therefore warranted. Circulating natriuretic peptides (NPs) are strong predictors of MAEs and mortality in chronic HF patients. However, whether NPs can identify patients who are at risk of MAEs and mortality or tend toward myocardial recovery after LVAD implantation is unclear. The aim of this systematic review is to analyze the prognostic value of circulating NP levels before LVAD implantation for all-cause mortality, MAEs and myocardial recovery after LVAD implantation.

Methods and Results: Electronic databases were searched for studies analyzing circulating NP in adults with advanced HF before LVAD implantation in relation to mortality, MAEs, or myocardial recovery after LVAD implantation. Twenty-four studies published between 2008 and 2021 were included. Follow-up duration ranged from 48 hours to 5 years. Study sample size ranged from 14 to 15,138 patients. Natriuretic peptide levels were not predictive of all-cause mortality. However, NPs were predictive of right ventricular failure (RVF) and MAEs such as ventricular arrhythmias, moderate or severe aortic regurgitation, and all-cause rehospitalization. No relation between NPs and myocardial recovery was found.

Conclusion: This systematic review found that NP levels before LVAD implantation are not predictive of all-cause mortality after LVAD implantation. Thus, NP levels may be of limited value in patient selection for LVAD therapy. However, NPs help in risk stratification of MAEs and may be used to identify patients who are at risk for RVF, ventricular arrhythmias, moderate or severe aortic regurgitation, and all-cause rehospitalization after LVAD implantation.

Contemporary outcomes of continuous-flow biventricular assist devices

Background

Significant right ventricular failure (RVF) complicating left ventricular assist device (LVAD) placement has been reported at 10-30%. Although primarily indicated for left ventricular failure, ventricular assist devices (VADs) have become utilized in a biventricular setup to combat right ventricular failure (RVF) following LVAD implantation. With the advent of continuous-flow LVADs (CF-LVADs) superseding their pulsatile predecessors, the shift towards CF-biventricular assist devices (CF-BiVADs) come with the prospect of improved outcomes over previous pulsatile BiVADs. We aim to review the literature and determine the outcomes of CF-BiVAD recipients.

Methods

A systematic review was performed to determine the outcomes of CF-BiVADs. Pre-operative demographics and device configuration data was collected. Primary outcomes evaluated were short-term survival, long-term survival, duration of support, and survival to transplant. Secondary outcomes evaluated included intensive care unit (ICU) and hospital length of stay (ICU-LOS and HLOS, respectively), pump thrombosis, pump exchange. Median and interquartile range was reported where appropriate. A major limitation was the likely overlap of cohorts across publications, which may have contributed to some selection bias.

Results

Of 1,282 screened, 12 publications were evaluated. Sample size ranged from 4 to 93 CF-BiVAD recipients, and follow-up ranged from 6 to 24 months. Mean age ranged from 34 to 52 years old. Forty-five percent of CF-BiVADs had right atrial (RA-) inflow cannulation, with the remaining being right ventricular (RV). Thirty-day survival was a median of 90% (IQR 82-97.8%) and 12-month survival was a median of 58.5% (IQR 47.5-62%). Where reported, rate of pump thrombosis (predominantly the right VAD) was a median of 31% (IQR 14-36%), although pump exchange was only 9% (IQR 1.5-12.5%).

Conclusions

RVF post-LVAD implantation is a high morbidity and mortality complication. There is no on-label continuous-flow RVAD currently available. Thus, the modifications of LVADs for right ventricular support to combat pump thrombosis has resulted in various techniques. BiVAD recipients are predominantly transplant candidates, and complications of pump thrombosis and driveline infection whilst on wait-list are of great consequence. This study demonstrates the need for an on-label CF-BiVAD.

Progression of cardiac disease in patients with lamin A/C mutations

Aims

We aimed to study the progression of cardiac dysfunction in patients with lamin A/C mutations and explore markers of adverse cardiac outcome.

Methods and results

We followed consecutive lamin A/C genotype-positive patients divided into tertiles according to age. Patients underwent repeated clinical examinations, electrocardiograms (ECGs), and echocardiograms. We followed left ventricular (LV) and right ventricular (RV) size and function, and the severity atrioventricular-valve regurgitations. Outcome was death, LVAD implant, or cardiac transplantation. We included 101 patients [age 44 (29–54) years, 39% probands, 50% female]. We analysed 576 echocardiograms and 258 ECGs during a follow-up of 4.9 (interquartile range 2.5–8.2) years. The PR-interval increased at young age from 204 ± 73 to 212 ± 69 ms (P < 0.001), LV ejection fraction (LVEF) declined from middle age from 50 ± 12% to 47 ± 13% (P < 0.001), while LV volumes remained unchanged. RV function and tricuspid regurgitation worsened from middle age with accelerating rates. Progression of RV dysfunction [odds ratio (OR) 1.3, 95% confidence interval (CI) (1.03–1.65), P = 0.03] and tricuspid regurgitation [OR 4.9, 95% CI (1.64–14.9), P = 0.004] were associated with outcome when adjusted for age, sex, comorbidities, LVEF, and New York Heart Association functional class.

Conclusion

In patients with lamin A/C genotype, electrical disease started at young age. From middle age, LV function deteriorated progressively, while LV size remained unchanged. Worsening of RV function and tricuspid regurgitation accelerated in older age and were associated with outcome. Our systematic map on cardiac deterioration may help optimal monitoring and prognostication in lamin A/C disease.

Right ventricular failure after left ventricular assist device implantation: a review of the literature

Right ventricular failure (RVF) following left ventricular assist device (LVAD) implantation remains a major complication which may significantly impair patient outcome. The genesis of RVF is, however, multifactorial, and the mechanisms underlying such a condition have not been fully elucidated, making its prevention challenging and the course not always predictable. Although preoperative risks factors can be associated with RV impairment, the physiologic changes after the LV support, can still hamper the function of the RV. Current medical treatment options are limited and sometimes, patients with a severe post-LVAD RVF may be unresponsive to pharmacological therapy and require more aggressive treatment, such as temporary RV support. We retrieved 11 publications which we assessed and divided in groups based on the RV support [extracorporeal membrane oxygenation (ECMO), right ventricular assist device (RVAD), TandemHeart with ProtekDuo cannula]. The current review comprehensively summarizes the main studies of the literature with particular attention to the RV physiology and its changes after the LVAD implantation, the predictors and prognostic score as well as the different modalities of temporary mechanical cardio-circulatory support, and its effects on patient prognosis for RVF in such a setting. In addition, it provides a decision making of the pre-, intra and post-operative management in high- and moderate- risk patients.

A Modified Grading System for Early Right Heart Failure Matches Functional Outcomes and Survival After Left Ventricular Assist Devices

Early right heart failure (ERHF) remains a common complication after continuous-flow left ventricular assist device (cf-LVAD) and has been associated with increased mortality. The specific criteria used to define ERHF remain somewhat arbitrary. Correlating the degree of ERHF with outcomes after LVAD could inform a more clinically relevant definition. We identified 196 patients who underwent first durable cf-LVAD between 2008 and 2015 at a single center. Postimplant ERHF was graded as absent, mild (requiring inotropic support for 14-20 days), moderate (inotropes for ≥ 21 days), or severe (requiring unplanned RVAD at any time during the index hospitalization). ERHF was associated with clinical outcomes including 1 year survival and New York Heart Association (NYHA) class and 6 minute walk distance (6MWD) at 3 and 6 months. Survival was assessed using the Kaplan-Meier method with log-rank testing and multivariate Cox proportional-hazards modeling. Compared to patients without ERHF, those with mild ERHF had similar 1 year survival (hazard ratio [HR] 0.69, 95% confidence interval [CI]: 0.26-1.80, p = 0.45), while mortality was substantially increased in patients with moderate (HR 2.65, 95% CI: 1.27-5.54, p = 0.009) and severe ERHF (HR 8.16, 95% CI: 3.97-16.76, p < 0.0001). The severity of ERHF was associated with 6MWD at both 3 months (p = 0.001) and 6 months (p = 0.013). The relationship between ERHF and postimplant survival and functional status persisted in multivariate modeling. A simple, modified grading system for ERHF severity is strongly associated with 1 year survival and functional capacity after cf-LVAD. These results argue against using a binary definition for ERHF and suggest the need to modify definition of ERHF severity.

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.

Right Ventricular Strain to Assess Early Right Heart Failure in the Left Ventricular Assist Device Candidate

PURPOSE OF REVIEW

Right heart failure (RHF) following left ventricular assist device implantation (LVAD) remains the primary cause of postoperative mortality and morbidity, and prediction of RHF is the main interest of the transplantation community. In this review, we outline the role and impact of right ventricular strain in the evaluation of the right ventricle function before LVAD implantation.

RECENT FINDINGS

Accumulating data suggest that measurement of right ventricular longitudinal strain (RVLS) has a critical role in predicting RHF preoperatively and may improve morbidity and mortality following LVAD implantation. However, the significant intraobserver, interobserver variability, the lack of multicenter, prospective studies, and the need for a learning curve remain the most critical limitations in the clinical practice at present. This review highlighted the importance of right ventricular strain in the diagnosis of RHF preoperatively and revealed that RVLS might have a crucial clinical measurement for the selection and management of LVAD patients in the future with the more extensive multicenter studies.

A review of the management of patients with advanced heart failure in the intensive care unit

Despite progress in the medical and device therapy for heart failure (HF), the prognosis for those with advanced HF remains poor. Acute heart failure (AcHF) is the rapid development of, or worsening of symptoms and signs of HF typically leading to hospitalization. Whilst many HF decompensations are managed at a ward-based level, a proportion of patients require higher acuity care in the intensive care unit (ICU). Admission to ICU is associated with a higher risk of in-hospital mortality, and in those who fail to respond to standard supportive and medical therapy, a proportion maybe suitable for mechanical circulatory support (MCS). The optimal pre-operative management of advanced HF patients awaiting durable MCS or cardiac transplantation (CTx) is vital in improving both short and longer-term outcomes. This review will summarize the clinical assessment, hemodynamic profiling and management of the patient with AcHF in the ICU. The general principles of pre-surgical optimization encompassing individual systems (the kidneys, the liver, blood and glycemic control) will be discussed. Other factors impacting upon post-operative outcomes including nutrition and sarcopenia and pre-surgical skin decolonization have been included. Issues specific to durable MCS including the assessment of the right ventricle and strategies for optimization will also be discussed.

Clinical impact of concomitant tricuspid valve procedures during left ventricular assist device implantation

BACKGROUND

Tricuspid regurgitation (TR) is common in patients with end-stage heart failure receiving left ventricular assist devices (LVADs), but the benefit of concomitant tricuspid valve procedures (TVPs) remains uncertain. This study examined the impact of TVP at the time of LVAD implantation on clinical outcomes and quality of life (QOL) metrics.

METHODS

We included adult patients in the Interagency Registry for Mechanical Circulatory Support database with various degrees of TR who received continuous-flow LVADs from 2008 to 2017. Patients undergoing concomitant TVP were compared with those without the intervention in a stratified analysis. Descriptive analyses, survival analyses, and Andersen‒Gill hazard models were used as appropriate to examine associations with clinical and patient-centered QOL outcomes.

RESULTS

Our analysis included 8,263 (53.1%) mild, 4,252 (33.3%) moderate, and 2,100 (13.5%) severe TR cases. TVP rate increased with severity: 8.6% of mild, 18.0% of moderate, and 43.9% of severe cases. TVP was not associated with survival benefit in cases of mild (adjusted hazard ratio [aHR]: 0.97, 95% CI: 0.79-1.19, p = 0.75), moderate (aHR: 1.03, 95% CI: 0.88-1.20, p = 0.72), or severe (aHR: 1.20, 95% CI: 0.98-1.48, p = 0.08) TR. For patients with combined moderate or severe TR, TVP was associated with increased mortality (log-rank p < 0.01, aHR: 1.13, 95% CI: 1.00-1.27, p = 0.04). After adjusting for TR severity, TVP was associated with increased risk of bleeding, arrhythmia, and stroke (p < 0.01 each) and no improvements in QOL (p > 0.05).

CONCLUSIONS

TVP at the time of LVAD implantation was not associated with either improved survival or QOL, and there were associations with increased risk of adverse events among patients with moderate and severe TR.

Right ventricle failure in patients treated with left ventricular assist device

This review article aim to highlight the right ventricular function peri left ventricular assist device implantation, and to assess the incidence, physiopathology, predictors, management and prognosis, of right ventricular failure post-implant.

Continuous-Flow Left Ventricular Assist Devices and Valvular Heart Disease: A Comprehensive Review

Mechanical circulatory support with implantable durable continuous-flow left ventricular assist devices (CF-LVADs) represents an established surgical treatment option for patients with advanced heart failure refractory to guideline-directed medical therapy. CF-LVAD therapy has been demonstrated to offer significant survival, functional, and quality-of-life benefits. However, nearly one-half of patients with advanced heart failure undergoing implantation of a CF-LVAD have important valvular heart disease (VHD) present at the time of device implantation or develop VHD during support that can lead to worsening right or left ventricular dysfunction and result in development of recurrent heart failure, more frequent adverse events, and higher mortality. In this review, we summarize the recent evidence related to the pathophysiology and treatment of VHD in the setting of CF-LAVD support and include a review of the specific valve pathologies of aortic insufficiency (AI), mitral regurgitation (MR), and tricuspid regurgitation (TR). Recent data demonstrate an increasing appreciation and understanding of how VHD may adversely affect the hemodynamic benefits of CF-LVAD support. This is particularly relevant for MR, where increasing evidence now demonstrates that persistent MR after CF-LVAD implantation can contribute to worsening right heart failure and recurrent heart failure symptoms. Standard surgical interventions and novel percutaneous approaches for treatment of VHD in the setting of CF-LVAD support, such as transcatheter aortic valve replacement or transcatheter mitral valve repair, are available, and indications to intervene for VHD in the setting of CF-LVAD support continue to evolve.

Hemodynamics of concomitant tricuspid valve procedures at LVAD implantation

BACKGROUND

Tricuspid regurgitation (TR) is common in patients receiving left ventricular assist device (LVAD) implantation. The current literature is conflicting regarding the effects of concomitant tricuspid valve repair (TVR) at LVAD implantation. We investigated the hemodynamic effects of concomitant TVR at LVAD implantation.

METHODS

Consecutive clinically stable LVAD outpatients who underwent hemodynamic ramp testings were enrolled in this study, and they were stratified by concomitant TVR. Results of hemodynamic ramp tests were compared between the TVR group and the non-TVR group.

RESULTS

Among 65 LVAD patients undergoing ramp tests, 34 patients had received TVR, and 31 had not. There were no significant differences in baseline characteristics between two groups except for higher degree of TR and lower pulmonary artery pulsatility index in the TVR group (P < .05 for both). Following LVAD implantation, the degree of TR improved significantly in the TVR group down to the comparable level with the non-TVR group. During ramp tests, the TVR group had steeper cardiac index slope (0.14 ± 0.12 vs 0.07 ± 0.07 L/min/m² /step, P = .002) and higher cardiac index at set LVAD speed (2.99 ± 0.84 vs 2.52 ± 0.42 L/min/m² , P = .007).

CONCLUSIONS

Concomitant TVR improves cardiac output and its response to LVAD speed change following LVAD implantation. Longitudinal clinical implications of such hemodynamic changes are unknown.

Intraoperative Hemodynamic and Echocardiographic Measurements Associated With Severe Right Ventricular Failure After Left Ventricular Assist Device Implantation

BACKGROUND

Severe right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation increases morbidity and mortality. We investigated the association between intraoperative right heart hemodynamic data, echocardiographic parameters, and severe versus nonsevere RVF.

METHODS

A review of LVAD patients between March 2013 and March 2016 was performed. Severe RVF was defined by the need for a right ventricular mechanical support device, inotropic, and/or inhaled pulmonary vasodilator requirements for >14 days. From a chart review, the right ventricular failure risk score was calculated and right heart hemodynamic data were collected. Pulmonary artery pulsatility index (PAPi) [(pulmonary artery systolic pressure - pulmonary artery diastolic pressure)/central venous pressure (CVP)] was calculated for 2 periods: (1) 30 minutes before cardiopulmonary bypass (CPB) and (2) after chest closure. Echocardiographic data were recorded pre-CPB and post-CPB by a blinded reviewer. Univariate logistic regression models were used to examine the performance of hemodynamic and echocardiographic metrics.

RESULTS

A total of 110 LVAD patients were identified. Twenty-five did not meet criteria for RVF. Of the remaining 85 patients, 28 (33%) met criteria for severe RVF. Hemodynamic factors associated with severe RVF included: higher CVP values after chest closure (18 ± 9 vs 13 ± 5 mm Hg; P = .0008) in addition to lower PAPi pre-CPB (1.2 ± 0.6 vs 1.7 ± 1.0; P = .04) and after chest closure (0.9 ± 0.5 vs 1.5 ± 0.8; P = .0008). Post-CPB echocardiographic findings associated with severe RVF included: larger right atrial diameter major axis (5.4 ± 0.9 vs 4.9 ± 1.0 cm; P = .03), larger right ventricle end-systolic area (22.6 ± 8.4 vs 18.5 ± 7.9 cm; P = .03), lower fractional area of change (20.2 ± 10.8 vs 25.9 ± 12.6; P = .04), and lower tricuspid annular plane systolic excursion (0.9 ± 0.2 vs 1.1 ± 0.3 cm; P = .008). Right ventricular failure risk score was not a significant predictor of severe RVF. Post-chest closure CVP and post-chest closure PAPi discriminated severe from nonsevere RVF better than other variables measured, each with an area under the curve of 0.75 (95% CI, 0.64-0.86).

CONCLUSIONS

Post-chest closure values of CVP and PAPi were significantly associated with severe RVF. Echocardiographic assessment of RV function post-CPB was weakly associated with severe RVF.

Usefulness of right ventricular contraction pressure index to predict short-term mortality and right heart failure in patients who underwent continuous-flow left ventricular assist device implantation

Background:

Right ventricular stroke work index is a useful but invasively measured parameter that can be used to predict right heart failure following continuous-flow left ventricular assist device implantation. Right ventricular contraction pressure index is a novel parameter that was developed to measure right ventricular stroke work index with echocardiography. We aimed to investigate the clinical usefulness of right ventricular contraction pressure index to predict short-term mortality and right heart failure in patients who underwent continuous-flow left ventricular assist device implantation.

Methods:

A total of 49 patients who participated in institutional advanced heart failure registry and underwent continuous-flow left ventricular assist device implantation with a bridge-to-candidacy indication were analyzed retrospectively. Right ventricular contraction pressure index was calculated using offline measurements. Demographic, clinical and outcome data were obtained from the registry data. Patients were grouped according to right ventricular contraction pressure index quartiles.

Results:

Patients within the lowest right ventricular contraction pressure index quartile had a trend toward higher short-term mortality (46.2%, p = 0.056) and combined short-term mortality and definitive right heart failure (53.8%, p = 0.054) at 15th day postoperatively. Similarly, short-term survival or survival free of definite right heart failure were significantly lower in the lowest right ventricular contraction pressure index quartile (log-rank p = 0.045 and log-rank p = 0.03, respectively). In a proportional hazards model that included echocardiographic parameters, right ventricular contraction pressure index was an independent predictor for short-term mortality (odds ratio: 6.777, 95% confidence interval: 1.118–41.098, p = 0.037), but not for combined short-term mortality and definite right heart failure. No such associations were found for long-term mortality. Right ventricular contraction pressure index had a statistically significant correlation with invasively measured pulmonary capillary wedge pressure, pulmonary vascular resistance, mean pulmonary pressure, and right ventricular stroke work index.

Conclusion:

Right ventricular contraction pressure index was found as a useful parameter for determining short-term postoperative mortality in patients undergoing continuous-flow left ventricular assist device implantation.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

Long-term mechanical circulatory support (LT-MCS) is an important treatment modality for patients with severe heart failure. Different devices are available, and many-sometimes contradictory-observations regarding patient selection, surgical techniques, perioperative management and follow-up have been published. With the growing expertise in this field, the European Association for Cardio-Thoracic Surgery (EACTS) recognized a need for a structured multidisciplinary consensus about the approach to patients with LT-MCS. However, the evidence published so far is insufficient to allow for generation of meaningful guidelines complying with EACTS requirements. Instead, the EACTS presents an expert opinion in the LT-MCS field. This expert opinion addresses patient evaluation and preoperative optimization as well as management of cardiac and non-cardiac comorbidities. Further, extensive operative implantation techniques are summarized and evaluated by leading experts, depending on both patient characteristics and device selection. The faculty recognized that postoperative management is multidisciplinary and includes aspects of intensive care unit stay, rehabilitation, ambulatory care, myocardial recovery and end-of-life care and mirrored this fact in this paper. Additionally, the opinions of experts on diagnosis and management of adverse events including bleeding, cerebrovascular accidents and device malfunction are presented. In this expert consensus, the evidence for the complete management from patient selection to end-of-life care is carefully reviewed with the aim of guiding clinicians in optimizing management of patients considered for or supported by an LT-MCS device.

Noninvasive Assessment of Right Ventricular Function in Patients with Pulmonary Arterial Hypertension and Left Ventricular Assist Device

PURPOSE OF REVIEW

Right ventricular (RV) failure in patients with pulmonary arterial hypertension (PAH) and left ventricular assist device (LVAD) is associated with increased hospitalizations, worsening functional class, and poor survival. Accurate RV function assessment is essential in diagnosing RV failure, guiding therapies, and determining prognosis. Noninvasive imaging techniques provide fast and reliable quantification of RV morphology and function.

RECENT FINDINGS

We review echocardiography, nuclear medicine, and cardiac magnetic resonance imaging (MRI) uses for RV function assessment in patients with PAH and LVAD. We identify current knowledge gaps in utilizing noninvasive tests to assess RV function. Echocardiography is most widely used to quantify RV function in patients with PAH and LVAD, followed by cardiac MRI for RV morphology and function measurement in PAH patients. The first-pass radionuclide angiography with radiolabeled RBC is the gold standard for calculating RV function. Gated blood pool SPECT can be an alternative as it separates the cardiac chambers well and provides accurate assessment of the RV function with high reproducibility, which is particularly useful for monitoring treatment. More research is needed to compare and validate these modalities in evaluating RV function.

Mechanical circulatory support for the right ventricle in combination with a left ventricular assist device

Introduction: Right heart failure (RHF) in patients with a left ventricular assist device (LVAD) carries a poor prognosis although the treatment strategy including mechanical circulatory support for the failing right ventricle (RV) has not been well established. Areas covered: In this review, we describe an overview of RHF post-LVAD implant including natural history, prevalence, pathophysiology, outcomes, and challenges to predict RHF post-LVAD implant. Then, we focus on right ventricular assist devices (RVADs) and their clinical outcomes. Recently developed percutaneous RVADs are the major advance in this field. Finally, we discuss future perspectives to overcome limitations of the current treatment options. Expert opinion: In the absence of dedicated RVAD system RHF post-LVAD implant may have been undertreated. Now that dedicated percutaneous RVADs have emerged, surgeons are encouraged to use these new devices to improve outcomes of LVAD therapy. As experience accumulates, we should be able to establish the best possible strategy to treat early RHF post-LVAD implant. Late RHF is another form of RHF post-LVAD implant and has been underappreciated. Further research is mandatory to clarify the mechanism and risk factors. There are still unmet needs for a dedicated implantable RVAD for a subset of patients who need long-term RV support.

Left ventricular assist device implantation with concomitant tricuspid valve repair: is there really a benefit?

Background

The objectives of this study was to investigate if concomitant tricuspid valve repair in patients undergoing continuous flow left ventricular assist device (LVAD) implantation has an impact on the outcome regarding survival and adverse events.

Methods

Between June 2007 and February 2018, 124 consecutive patients received HeartMate II (HMII) [74 (59.7%)] HeartWare (HVAD) [16 (12.9%)], or HeartMate III (HM III) [34 (27.4%)] for end-stage heart failure. Mean age was 63.5±10.9 years. Two 18-patient groups were identified; with [tricuspid valve reconstruction (TVR)] group and without (non-TVR group) accompanying TVR. The primary endpoint was overall survival after device implantation. Secondary endpoints were adverse events during the follow-up period.

Results

Survival was not significantly different between the groups (P>0.05). In TVR group, there was a higher need for open chest after surgery and a prolonged inotrope use because of right heart failure (RHF), a higher incidence of acute kidney dysfunction requiring dialysis, as well as a higher need for packed red blood cells due to postoperative bleeding (P<0.05).

Conclusions

In this cohort of patients, LVAD implantation with a concurrent tricuspid valve repair appears to have a worse outcome regarding RHF, bleeding tendency and renal dysfunction (P<0.05). However, the survival was comparable in both TVR and Non-TVR groups (P>0.05).

Atrial Fibrillation Should Guide Prophylactic Tricuspid Procedures During Left Ventricular Assist Device Implantation

Atrial fibrillation (AF) and tricuspid regurgitation (TR) are common in patients undergoing left ventricular assist device (LVAD) implantation. TR progression is associated with the presence of AF, and questions remain as to who benefits from tricuspid valve procedures (TVPs). We examined the impact of preoperative AF on TR progression after LVAD implantation. From February 2007 to May 2014, 250 patients underwent LVAD implantation at our institution. Patients with concomitant TVP were excluded from this analysis (113 patients). The indication for LVAD was destination therapy in 80 patients (58%) and the etiology of heart failure was ischemic in 73 (53%). Follow-up was available in all early survivors for a total of 393 patient-years of support. Of the 137 non-TVP patients, 52 (38%) had AF preoperatively. Observed overall survival at 1, 3, and 5 years was 82%, 67%, and 55%, respectively. Median grade of TR increased from 2 preoperatively to 3 (p = 0.04) in the AF group and 2.2 (p = 0.75) in the non-AF group at 5 years of follow-up. We also observed a significant difference in the degree of TR between groups at 3 months (p = 0.03) and 12 months (p = 0.01) postimplantation, and a trend toward significance at 18 (p = 0.06) and 24 (p = 0.07) months. The presence of AF is associated with early progression of TR after LVAD implantation. Addition of concomitant TVP in patients with preoperative AF may be considered in patients with less than severe TR. The impact of these findings on right ventricular failure/remodeling remains to be evaluated.

Role of imaging in diagnosis and management of left ventricular assist device complications

Heart failure is a clinical condition that is associated with significant morbidity and mortality. With the advent of left ventricular assist device (LVAD), an increasing number of patients have received an artificial heart both as a bridge-to-therapy and as a destination therapy. Clinical trials have shown clear survival benefits of LVAD implantation. However, the increased survival benefits and improved quality of life come at the expense of an increased complication rate. Common complications include perioperative bleeding, infection, device thrombosis, gastrointestinal bleeding, right heart failure, and aortic hemodynamic changes. The LVAD-associated complications have unique pathophysiology. Multiple imaging modalities can be employed to investigate the complications, including computed tomography (CT), positron emission tomography-computed tomography (PET-CT), catheter angiography and echocardiography. Imaging studies not only help ascertain diagnosis and evaluate the severity of disease, but also help direct relevant clinical management and predict prognosis. In this article, we aim to review the common LVAD complications, present the associated imaging features and discuss the role of imaging in their management.

Choosing Between Left Ventricular Assist Devices and Biventricular Assist Devices

Right ventricular failure following left ventricular assist devices implantation is a serious complication associated with high mortality. In patients with or at high risk of developing right ventricular failure, biventricular support is recommended. Because univentricular support is associated with high survival rates, biventricular support is often undertaken as a last resort. With the advent of newer right ventricular and biventricular systems under design and testing, better differentiation is required to ensure optimal patients care. Clear guidelines on patient selection, time of intervention and device selection are required to improve patient outcomes.

Extracorporeal membrane oxygenation support for right ventricular failure after left ventricular assist device implantation

OBJECTIVES

Right ventricular (RV) failure complicating left ventricular assist device implantation is associated with increased mortality. Despite a lack of supporting evidence, venoarterial extracorporeal membrane oxygenation (ECMO) support is increasingly being used as an alternative to traditional temporary RV support. We report our institutional experience with ECMO-facilitated RV support after left ventricular assist device implantation.

METHODS

We retrospectively reviewed the concept of temporary ECMO support for perioperative RV failure in 32 consecutive left ventricular assist device (mean age 52 ± 14 years; male 84.4%; ischaemic cardiomyopathy 40.6%; INTERMACS Level I 71.8%; INTERMACS Level II 6.3%; INTERMACS Level III 12.5%; INTERMACS Level IV-VII 9.4%; HeartWare ventricular assist device 75%; HeartMate II: 25%) from May 2009 to April 2014. The study end points were RV recovery during ECMO support, mortality and causes of death.

RESULTS

Twenty-nine (90.6%) patients were successfully weaned from ECMO support after RV recovery. Three (9.4%) patients expired during ECMO support. ECMO support improved RV function and haemodynamic parameters (central venous pressure 13 mmHg vs 10 mmHg, P < 0.01; mean pulmonary artery pressure 28 mmHg vs 21 mmHg, P < 0.01; cardiac output 5.1 l/min vs 5.9 l/min, P = 0.09) over a median period of 3 (range 1-15) days. Thirty-day and in-hospital mortality were 18.8% and 25%, respectively. One-year survival was 75%, causes of death were multiorgan dysfunction syndrome (50%), sepsis (25%), haemorrhagic stroke (12.5%) and ischaemic stroke (12.5%). Causes of death during ECMO support were ischaemic stroke, sepsis and multiorgan dysfunction syndrome.

CONCLUSIONS

Temporary ECMO-facilitated RV support is associated with good long-term outcomes and high rates of RV recovery.

Promising utilization areas of therapeutic plasmapheresis in cardiovascular surgery practice

OBJECTIVE

Apheresis is performed for treatment of numerous diseases by removing auto-antibodies, antigen-antibody complexes, allo-antibodies, paraproteins, non-Ig proteins, toxins, exogenous poisons. In current study, we present our experience of using therapeutic plasma exchange (TPE) in patients with different types of clinical scenarios.

METHODS

Between January 2013 and May 2016, we retrospectively presented the results of 64 patients in whom postoperative TPE was performed in ICU setting after cardiac surgery. Patients were grouped into four as; 1-sepsis (n = 26), 2-hepatorenal syndrome(n = 24), 3-antibody mediated rejection(AMR) following heart transplantation(n = 4) and 4-right heart failure(RHF) after left ventricular asist device(LVAD)(n = 10). Hemodynamic parameters were monitored constantly, pre- and post-procedure peripheral blood tests including renal and liver functions and daily complete blood count (CBC), sedimentation, C-reactive protein and procalcitonin (ng/ml) levels were studied.

RESULTS

The mean age was 61 ± 17.67 years old and 56.25% (n = 36) were male. Mean Pre TPE left ventricular ejection fraction (LVEF) (%), central venous pressure (CVP)(mmHg) pulmonary capillary wedge pressure (PCWP)(mmHg) and pulmonary arterial pressure (PAP)(mmHg) were measured as 41.8 ± 8.1, 15.5 ± 4.4, 17.3 ± 3.24 and 39.9 ± 5.4, respectively. Procalcitonin (ng/ml) level of patients undergoing TPE due to sepsis was significantly reduced from 873 ± 401 ng/ml to 248 ± 132 ng/ml. Seventeen (26.5%) patients died in hospital during treatment, mean length of intensive care unit (ICU) stay(days) was 13.2 ± 5.1.

CONCLUSION

This study shows that TEP is a safe and feasible treatment modality in patients with different types of complications after cardiac surgery and hopefully this study will lead to new utilization areas.

Wave Intensity Analysis of Right Ventricular Function during Pulsed Operation of Rotary Left Ventricular Assist Devices

Changing the speed of left ventricular assist devices (LVADs) cyclically may be useful to restore aortic pulsatility; however, the effects of this pulsation on right ventricular (RV) function are unknown. This study investigates the effects of direct ventricular interaction by quantifying the amount of wave energy created by RV contraction when axial and centrifugal LVADs are used to assist the left ventricle. In 4 anesthetized pigs, pressure and flow were measured in the main pulmonary artery and wave intensity analysis was used to identify and quantify the energy of waves created by the RV. The axial pump depressed the intensity of waves created by RV contraction compared with the centrifugal pump. In both pump designs, there were only minor and variable differences between the continuous and pulsed operation on RV function. The axial pump causes the RV to contract with less energy compared with a centrifugal design. Diminishing the ability of the RV to produce less energy translates to less pressure and flow produced, which may lead to LVAD-induced RV failure. The effects of pulsed LVAD operation on the RV appear to be minimal during acute observation of healthy hearts. Further study is necessary to uncover the effects of other modes of speed modulation with healthy and unhealthy hearts to determine if pulsed operation will benefit patients by reducing LVAD complications.

Role of multimodality imaging in patients with left ventricular assist device

PURPOSE OF REVIEW

The article provides an overview of recent advances in imaging patients with a left ventricular assist device (LVAD).

RECENT FINDINGS

There is a growing population of patients with LVADs. LVADs improve survival in patients with end-stage heart failure, but are also associated with significant adverse outcomes. Imaging, particularly echocardiography, plays a critical role in patient selection and in predicting and detecting complications.

SUMMARY

Recent studies have illustrated links between imaging parameters with adverse outcomes, such as pump thrombosis, right ventricular failure, and continuous aortic regurgitation. Novel parameters and imaging techniques have been developed.