Predicting Long Term Outcome in Patients Treated With Continuous Flow Left Ventricular Assist Device: The Penn-Columbia Risk Score

A Machine Learning Derived Risk Score Improves Prediction of Outcomes Post-LVAD Implantation: An Analysis of the INTERMACS database

BACKGROUND

Significant variability in post-left ventricular assist device (LVAD) implantation outcomes emphasize the importance of accurately assessing patients' risk prior to surgery. This study assesses the MARKER-HF mortality risk model, a machine learning-based tool utilizing 8 clinical variables, to predict post-LVAD implantation mortality and its prognostic enhancement over the INTERMACS profile.

METHODS

Analyzing 25,365 INTERMACS database patients (mean age 56.8 years, 78% male), 5,663 (22.3%) and 19,702 (77.7%) received HeartMate 3 and other types of LVAD. They were categorized into low, moderate, high, and very high-risk groups based on MARKER-HF score. The outcomes of interest were in-hospital and 1-year post-discharge mortality.

RESULTS

In patients receiving HM3 devices, 6.2% died during index hospitalization. In-hospital mortality progressively increased from 4.4% in low to 15.2% in very high -risk groups with MARKER-HF score. MARKER-HF provided additional risk discrimination within each INTERMACS profile. Combining MARKER-HF score and INTERMACS profile identified patients with the lowest (3.5%) and highest in-hospital mortality (19.8%) rates. Post-discharge mortality rate at one year was 5.8% in this population. In a Cox-proportional hazard regression analysis adjusting for both MARKER-HF and INTERMACS profile, only MARKER-HF score (hazard ratio: 1.27, 95% CI: 1.11-1.46, P<0.001) was associated with post-discharge mortality. Similar findings were observed for patients receiving other types of LVAD.

CONCLUSIONS

The MARKER-HF score is a valuable tool for assessing mortality risk in HF patients undergoing HM3 and other LVAD implantation. It offers prognostic information beyond that of the INTERMACS profile alone and it's use should help in the shared decision-making process for LVAD implantation.

A multicenter evaluation of the HeartMate 3 risk score

BACKGROUND

The Heartmate 3 (HM3) risk score (HM3RS) was derived and validated internally from within the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 (MOMENTUM 3) trial population and provides 1- and 2-year mortality risk prediction for patients in those before HM3 left ventricular assist device (LVAD) implantation. We aimed to evaluate the HM3RS in nontrial unselected patients, including those not meeting inclusion criteria for MOMENTUM 3 trial enrollment.

METHODS

Patients who underwent HM3 LVAD implant at 1 of 7 US centers between 2017 and 2021, with at least 1-year follow-up, were included in this analysis. Patients were retrospectively assessed for their eligibility for the MOMENTUM 3 trial based on study inclusion and exclusion criteria. HM3RS risk discrimination was evaluated using time-dependent receiver operating characteristic curve analysis for 1-year mortality for all patients and further stratified by MOMENTUM 3 trial eligibility. Kaplan-Meier curves were constructed using the HM3RS-based risk categories.

RESULTS

Of 521 patients included in the analysis, 266 (51.1%) would have met enrollment criteria for MOMENTUM 3. The 1- and 2-year survival for the total cohort was 85% and 81%, respectively. There was no statistically significant difference in survival between those who met and did not meet enrollment criteria at 1 (87% vs 83%; p = 0.21) and 2 years postimplant (80% vs 78%; p = 0.39). For the total cohort, HM3RS predicted 1-year survival with an area under the curve (AUC) of 0.63 (95% confidence interval [CI]: 0.57-0.69, p < 0.001). HM3RS performed better in the subset of patients meeting enrollment criteria: AUC 0.69 (95% CI:0.61-0.77, p < 0.001) compared to the subset that did not: AUC 0.58 (95% CI: 0.49-0.66, p = 0.078).

CONCLUSIONS

In this real-world evidence, multicenter cohort, 1- and 2-year survival after commercial HM3 LVAD implant was excellent, regardless of trial eligibility. The HM3RS provided adequate risk discrimination in "trial-like" patients, but predictive value was reduced in patients who did not meet trial criteria.

Validation of the Minnesota Pectoralis Risk Score to predict mortality in the HeartMate 3 population

BACKGROUND

The Minnesota Pectoralis Risk Score (MPRS) utilizes computed tomography-quantified thoracic muscle and clinical variables to predict survival after left ventricular assist device (LVAD) implantation. The model has not been prospectively tested in HeartMate 3 recipients.

METHODS

A single-center HeartMate 3 cohort from July 2016 to July 2021 (n = 108) was utilized for this analysis. Cohort subjects with complete covariates for MPRS calculation (pectoralis muscle measures, Black race, creatinine, total bilirubin, body mass index, bridge to transplant status, and presence/absence of contrast) implanted after MPRS development were included. MPRS were calculated on each subject. Receiver operating characteristic curves were generated to test model discrimination at 30-day, 90-day, and 1-year mortality post-LVAD. Next, the performance of the 1-year post-LVAD outcome was compared to the HeartMate 3 survival risk score (HM3RS).

RESULTS

The mean age was 58 (15 years), 80% (86/108) were male, and 26% (28/108) were destination therapy. The area under the curve (AUC) for the MPRS model to predict post-LVAD mortality was 0.73 at 30 days, 0.78 at 90 days, and 0.81 at 1 year. The AUC for the HM3RS for the 1-year outcome was 0.693. Each 1-unit point of the MPRS was associated with a significant increase in the hazard rate of death after LVAD (hazard ratio 2.1, 95% confidence interval 1.5-3.0, p < 0.0001).

CONCLUSIONS

The MPRS had high performance in this prospective validation, particularly with respect to 90-day and 1-year post-LVAD mortality. Such a tool can provide additional information regarding risk stratification to aid informed decision-making.

How to select a patient for LVAD

Left ventricular assist device (LVAD) implantation leads to improvement in symptoms and survival in patients with advanced heart failure. An important factor in improving outcomes post-LVAD implantation is optimal preoperative patient selection and optimization. In this review, we highlight the latest on the evaluation of patients with advanced heart failure for LVAD candidacy, including discussion of patient selection, implantation timing, laboratory and other testing considerations, and the importance of psychosocial evaluation. Such thorough evaluation by multidisciplinary team can serve to improve the outcomes of a complex group of patients with advanced heart failure being evaluated for LVAD.

Is pectoralis muscle index a risk factor for mortality in left ventricular assist device patients?

OBJECTIVE

We aimed to investigate whether sarcopenia measured from pectoralis muscles is a risk factor for long-term mortality in left ventricular assist device patients.

METHODS

Patients aged >18 years implanted with a left ventricular assist device in a single center between 2013 and 2019 were retrospectively included. Patients without a thoracic computed tomography scan performed within 3 months of left ventricular assist device implantation and without computed tomography scans appropriate for pectoralis muscle measurement were excluded. Pectoralis muscle measurements were made on thoracic computed tomography slices, and pectoralis muscle indices were calculated for each patient. Sarcopenia was defined as being in the gender-specific lowest tertile of pectoralis muscle index. Survival was compared between patients with and without sarcopenia.

RESULTS

The study was conducted on 64 left ventricular assist device patients who met the inclusion criteria. Notably, 21 (32.8%) of the study patients were sarcopenic. Diabetes mellitus and sarcopenia were more common in patients with 2-year mortality in our cohort. Patients with sarcopenia had a worse 2-year survival (p<0.001). Sarcopenia had an adjusted hazard ratio of 4.04 (95% confidence interval (CI) 1.36-12.02, p=0.012), while diabetes mellitus was associated with an adjusted hazard ratio of 3.14 (95%CI 1.17-8.39, p=0.023).

CONCLUSION

Sarcopenia defined by low pectoralis muscle index increases the risk for 2-year mortality in left ventricular assist device patients.

Hypotension on cardiopulmonary stress test predicts 90 day mortality after LVAD implantation in INTERMACS 3-6 patients

AIMS

Cardiopulmonary stress test (CPX) is routinely performed when evaluating patient candidacy for left ventricular assist device (LVAD) implantation. The predictive value of hypotensive systolic blood pressure (SBP) response during CPX on clinical outcomes is unknown. This study aims to determine the effect of hypotensive SBP response during to clinical outcomes among patients who underwent LVAD implantation.

METHODS AND RESULTS

This was a retrospective single center study enrolling consecutive patients implanted with a continuous flow LVAD between 2011 and 2022. Hypotensive SBP response was defined as peak exercise SBP below the resting value. Multivariable Cox-regression analysis was performed to evaluate the relationship between hypotensive SBP response and all-cause mortality within 30 and 90 days of LVAD implantation. A subgroup analysis was performed for patients implanted with a HeartMate III (HM III) device. Four hundred thirty-two patients underwent LVAD implantation during the pre-defined period and 156 with INTERMACS profiles 3-6 met our inclusion criteria. The median age was 63 years (IQR 54-69), and 52% had ischaemic cardiomyopathy. Hypotensive SBP response was present in 35% of patients and was associated with increased 90 day all-cause mortality (unadjusted HR 9.16, 95% CI 1.98-42; P = 0.0046). Hazard ratio remained significant after adjusting for age, INTERMACS profile, serum creatinine, and total bilirubin. Findings were similar in the HM III subgroup.

CONCLUSIONS

Hypotensive SBP response on pre-LVAD CPX is associated with increased perioperative and 90 day mortality after LVAD implantation. Additional studies are needed to determine the mechanism of increased mortality observed.

In a large-volume multidisciplinary setting individual surgeon volume does not impact LVAD outcomes

Background

In complex operations surgeon volume may impact outcomes. We sought to understand if individual surgeon volume affects left ventricular assist device (LVAD) outcomes.

Methods

We reviewed primary LVAD implants at an experienced ventricular assist devices (VAD)/transplant center between 2013 and 2019. Cases were dichotomized into a high‐volume group (surgeons averaging 11 or more LVAD cases per year), and a low‐volume group (10 or less per year). Propensity score matching was performed. Survival to discharge, 1‐year survival, and incidence of major adverse events were compared between the low‐ and high‐volume groups. Predictors of survival were identified with multivariate analysis.

Results

There were 315 patients who met inclusion criteria‐45 in the low‐volume group, 270 in the high‐volume group. There was no difference in survival to hospital discharge between the low (91.9%) and high (83.3%) volume matched groups (p = .22). Survival at 1‐year was also similar (85.4% vs. 80.6%, p = .55). There was no difference in the incidence of major adverse events between the groups. Predictors of mortality in the first year included: age (hazards ratio [HR]: 1.061, p < .001), prior sternotomy (HR: 1.991, p = .01), increasing international normalized ratio (HR: 4.748, p < .001), increasing AST (HR: 1.001, p < .001), increasing bilirubin (HR: 1.081, p = .01), and preoperative mechanical ventilation (HR: 2.662, p = .005). Individual surgeon volume was not an independent predictor of discharge or 1‐year survival.

Conclusion

There was no difference in survival or adverse events between high and low volume surgeons suggesting that, in an experienced multidisciplinary setting, low‐volume VAD surgeons can achieve similar outcomes to their high‐volume colleagues.

Left Ventricular Assist Device Thrombosis: Combined Approach by Echocardiography and Logfiles Review for Diagnosis and Management

Introduction

Left ventricular assist devices are an established therapy for end-stage heart failure. Follow-up of these patients showed complications, such as thrombosis. Our objective was to evaluate the contribution of echocardiography — in association with HeartWare HVAD online logfiles reviews and lactate dehydrogenase titration — for diagnosis and treatment of thrombosis.

Methods

Seventeen episodes of thrombosis were diagnosed in 8/20 patients with HVAD. Diagnosis was made by trans-thoracic echocardiographic blood flow velocities, logfiles review of power consumption and pump flows, and titration of lactate dehydrogenase. Data were collected at baseline routine control (Group A), during thrombosis (Group B), after thrombolysis (Group C).

Results

Thrombolysis was successful in all cases; one patient died of cerebral haemorrhage. Echocardiographic maximal blood flow velocity near the inflow cannula was 598±42 cm/sec (Group B), 379.41±21 cm/sec (Group C), and 378.24±28 cm/sec (Group A) (P<0.00001). In eight (47%) cases, thrombi were visualized in the left ventricle by three-dimensional modality. Logfiles recordings of blood flows were 9.52±0.9 L/min (Group B), 4.02±0.4 L/min (Group C), and 4.04±0.4 L/min (Group A) (P<00001). Power consumption was 5.01±0.7 W (Group B), 3.45±0.2 W (Group C), and 3.46±0.2 W (Group A) (P<0.00001). Lactate dehydrogenase was 756±54 IU (Group B), 234±22 IU (Group A), and 257±36 IU (Group C) (P<0.00001).

Conclusions

Echocardiography of increased maximal velocity near the inflow cannula is a sign of HVAD obstruction. Logfile reviews provide a clear picture of HVAD obstruction. Combination of echocardiographic data and review of logfiles detects signs of left ventricular assist devices thrombosis leading to a successful treatment.

Long-term survival on LVAD support: Device complications and end-organ dysfunction limit long-term success

BACKGROUND

Preoperative variables can predict short term left ventricular assist device (LVAD) survival, but predictors of extended survival remain insufficiently characterized.

METHOD

Patients undergoing LVAD implant (2012-2018) in the Intermacs registry were grouped according to time on support: short-term (<1 year, n = 7,483), mid-term (MT, 1-3 years, n = 5,976) and long-term (LT, ≥3 years, n = 3,015). Landmarked hazard analyses (adjusted hazard ratio, HR) were performed to identify correlates of survival after 1 and 3 years of support.

RESULTS

After surviving 1 year of support, additional LVAD survival was less likely in older (HR 1.15 per decade), Caucasian (HR 1.22) and unmarried (HR 1.16) patients (p < 0.05). After 3 years of support, only 3 preoperative characteristics (age, race, and history of bypass surgery, p < 0.05) correlated with extended survival. Postoperative events most negatively influenced achieving LT survival. In those alive at 1 year or 3 years, the occurrence of postoperative renal (creatinine HR MT = 1.09; LT HR = 1.10 per mg/dl) and hepatic dysfunction (AST HR MT = 1.29; LT HR = 1.34 per 100 IU), stroke (MT HR = 1.24; LT HR = 1.42), infection (MT HR = 1.13; LT HR = 1.10), and/or device malfunction (MT HR = 1.22; LT HR = 1.46) reduced extended survival (all p ≤ 0.03).

CONCLUSIONS

Success with LVAD therapy hinges on achieving long term survival in more recipients. After 1 year, extended survival is heavily constrained by the occurrence of adverse events and postoperative end-organ dysfunction. The growth of destination therapy intent mandates that future LVAD studies be designed with follow up sufficient for capturing outcomes beyond 24 months.

Novel Risk Model to Predict Emergency Department Associated Mortality for Patients Supported With a Ventricular Assist Device: The Emergency Department-Ventricular Assist Device Risk Score

Background The past decade has seen tremendous growth in patients with ambulatory ventricular assist devices. We sought to identify patients that present to the emergency department (ED) at the highest risk of death. Methods and Results This retrospective analysis of ED encounters from the Nationwide Emergency Department Sample includes 2010 to 2017. Using a random sampling of patient encounters, 80% were assigned to development and 20% to validation cohorts. A risk model was derived from independent predictors of mortality. Each patient encounter was assigned to 1 of 3 groups based on risk score. A total of 44 042 ED ventricular assist device patient encounters were included. The majority of patients were male (73.6%), <65 years old (60.1%), and 29% presented with bleeding, stroke, or device complication. Independent predictors of mortality during the ED visit or subsequent admission included age ≥65 years (odds ratio [OR], 1.8; 95% CI, 1.3-4.6), primary diagnoses (stroke [OR, 19.4; 95% CI, 13.1-28.8], device complication [OR, 10.1; 95% CI, 6.5-16.7], cardiac [OR, 4.0; 95% CI, 2.7-6.1], infection [OR, 5.8; 95% CI, 3.5-8.9]), and blood transfusion (OR, 2.6; 95% CI, 1.8-4.0), whereas history of hypertension was protective (OR, 0.69; 95% CI, 0.5-0.9). The risk score predicted mortality areas under the curve of 0.78 and 0.71 for development and validation. Encounters in the highest risk score strata had a 16-fold higher mortality compared with the lowest risk group (15.8% versus 1.0%). Conclusions We present a novel risk score and its validation for predicting mortality of patients with ED ventricular assist devices, a high-risk, and growing, population.

An Increasing Burden of Disease: Emergency Department Visits Among Patients With Ventricular Assist Devices From 2010 to 2017

Background With a growing population of patients supported by ventricular assist devices (VADs) and the improvement in survival of this patient population, understanding the healthcare system burden is critical to improving outcomes. Thus, we sought to examine national estimates of VAD-related emergency department (ED) visits and characterize their demographic, clinical, and outcomes profile. Additionally, we tested the hypotheses that resource use increased and mortality improved over time. Methods and Results This retrospective database analysis uses encounter-level data from the 2010 to 2017 Nationwide Emergency Department Sample. The primary outcome was mortality. From 2010 to 2017, >880 million ED visits were evaluated, with 44 042 VAD-related ED visits identified. The annual mean visits were 5505 (SD 4258), but increased 16-fold from 2010 to 2017 (824 versus 13 155). VAD-related ED visits frequently resulted in admission (72%) and/or death (3.0%). Median inflation-adjusted charges were $25 679 (interquartile range, $7450, $63 119) per encounter. The most common primary diagnoses were cardiac (22%), and almost 30% of encounters were because of bleeding, stroke, or device complications. From 2010 to 2017, admission and mortality decreased from 82% to 71% and 3.4% to 2.4%, respectively (P for trends <0.001, both). Conclusions We present the first study using national-level data to characterize the growing ED resource use and financial burden of patients supported by VAD. During the past decade, admission and mortality rates decreased but remain substantial; in 2017 ≈1 in every 40 VAD ED encounters resulted in death, making it critical that clinical decision-making be optimized for patients with VAD to maximize good outcomes.

Strategies of Wait-listing for Heart Transplant vs Durable Mechanical Circulatory Support Alone for Patients With Advanced Heart Failure

Importance

Given the shortage of donor hearts and improvement in outcomes with left ventricular assist device (LVAD) therapy, a relevant but, to date, unanswered question is whether select patients with advanced heart failure should receive LVAD destination therapy as an alternative to heart transplant.

Objective

To determine whether a strategy of LVAD destination therapy is associated with similar survival benefit as wait-listing for heart transplant with or without LVAD therapy among patients with advanced heart failure.

Design, Setting, and Participants

This retrospective propensity-matched cohort analysis used data on heart transplants from the United Network for Organ Sharing registry and LVAD implants from the Interagency Registry for Mechanically Assisted Circulatory Support from January 1, 2010, to December 31, 2014. The matched LVAD destination therapy cohort included 3411 patients. Data analysis for this study was conducted from December 22, 2017, to May 24, 2019.

Main Outcomes and Measures

Survival at 5 years was analyzed using Cox proportional hazards models.

Results

In total, 8281 patients had albumin level, creatinine level, and BMI data recorded and were included in the analysis. Despite propensity score matching, the 3411 patients receiving LVAD destination therapy still tended to be slightly older than the 3411 patients wait-listed for heart transplant (64.0 years [interquartile range, 55.0-70.0 years] vs 60.0 [interquartile range, 54.0-65.0 years]; P < .001), but there was no significant difference in sex (2701 men [79.2%] vs 2648 men [77.6%]; P = .13). After propensity score matching for age, sex, body mass index, renal function, and albumin level, 3411 patients were wait-listed for heart transplant. This included 1607 patients with bridge to transplant LVAD therapy and 1804 patients without LVAD. The strategy of wait-listing for heart transplant was associated with better 5-year survival than LVAD destination therapy (risk ratio, 0.42; 95% CI, 0.38-0.46) after matching and adjusting for key clinical factors. This survival advantage was associated with heart transplant (adjusted risk ratio for time-dependent transplant status, 0.27; 95% CI, 0.24-0.32).

Conclusions and Relevance

The present analysis suggests that heart transplant with or without bridge to transplant LVAD therapy was associated with superior 5-year survival compared with LVAD destination therapy among patients matched on several relevant clinical factors. Continued improvement in LVAD technology, along with prospective comparative research, appears to be needed to amend this strategy.

Assessment of Mortality Among Durable Left Ventricular Assist Device Recipients Ineligible for Clinical Trials

Importance

While wide-scale adoption of durable left ventricular assist devices (LVADs) can be attributed to favorable randomized clinical trial outcomes, restrictive selection criteria may be associated with a lack of generalizability to real-world experience.

Objective

To estimate the proportion of LVAD recipients who are eligible for clinical trials and to assess whether an association exists between trial eligibility and mortality.

Design, Setting, and Participants

This cohort study examined 14 679 patients undergoing primary, intracorporeal continuous-flow LVAD implantation (with or without a right ventricular assist device) in 181 North American centers from January 1, 2012, to June 30, 2017, identified in the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). To simulate a trial population, trial criteria from the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Therapy With HeartMate 3 (MOMENTUM 3) were mapped to INTERMACS variables. Patients were categorized as eligible for trial inclusion or ineligible for trial inclusion and by number of ineligibility criteria met. Follow-up in INTERMACS was complete for all patients through October 31, 2017. Data were analyzed from July 2019 through November 2020.

Exposures

Undergoing durable LVAD implantation.

Main Outcomes and Measures

Trial eligibility and postimplant mortality were analyzed using Kaplan-Meier estimates and Cox proportional hazards models.

Results

Among 14 679 recipients, mean (SD) age was 57 (13) years, 11 503 individuals (78.4%) were men, and 11 406 individuals (77.7%) presented with New York Heart Association class IV heart failure. A total of 6429 recipients (43.8%) were ineligible for trial inclusion, of whom 4226 individuals (65.7%) met 1 ineligibility criterion, 1442 individuals (22.4%) met 2 criteria, and 761 individuals (11.8%) met 3 or more criteria. Estimated mortality for recipients who were trial-ineligible was higher than for recipients who were trial-eligible (1-year mortality: 25.3% [95% CI, 24.2%-26.5%] vs 16.2% [95% CI, 15.4%-17.1%]; 3-year mortality: 42.8% [95% CI, 41.3%-44.4%] vs 36.4% [95% CI, 35.0%-37.8%]; log-rank P < .001 for both). Patients who were trial-ineligible had increased risk of mortality compared with patients who were trial-eligible if they met 1 trial ineligibility criterion (hazard ratio [HR], 1.16 [95% CI, 1.08-1.24]; P < .001), 2 trial ineligibility criteria (HR, 1.51 [95% CI, 1.36-1.67]; P < .001), or 3 or more trial ineligibility criteria (HR, 2.09 [95% CI, 1.84-2.39]; P < .001). Among patients meeting only 1 ineligibility criterion, 4 criteria were independently associated with mortality: prior or ongoing mechanical circulatory support (HR, 1.63 [95% CI, 1.23-2.16]; P = .001), elevated creatinine level (HR, 1.42 [95% CI, 1.17-1.72]; P < .001), elevated bilirubin level (HR, 1.39 [95% CI, 1.17-1.66]; P < .001), and low albumin or prealbumin level (HR, 1.18 [95% CI, 1.05-1.33]; P = .007).

Conclusions and Relevance

These findings suggest that while treatment for patients who are ineligible for LVAD trial inclusion should be weighed against medical management, more consideration could be given to designing trials with eligibility criteria that reflect real-world experience.

Left Ventricular Assist Device as Destination Therapy: a State of the Science and Art of Long-Term Mechanical Circulatory Support

PURPOSE OF REVIEW

The purpose of this review is to synthesize and summarize recent developments in the care of patients with end-stage heart failure being managed with a left ventricular assist device (LVAD) as destination therapy.

RECENT FINDINGS

Although the survival of patients treated with LVAD continues to improve, the rates of LVAD-associated complication, such as right ventricular failure, bleeding complications, and major infection, remain high, and management of these patients remains challenging. The durability and hemocompatibility of LVAD support have greatly increased in recent years as a result of new technologies and novel management strategies. Challenges remain in the comprehensive care of patients with destination therapy LVADs, including management of comorbidities and optimizing patient function and quality of life.

Biomarkers in Advanced Heart Failure: Implications for Managing Patients With Mechanical Circulatory Support and Cardiac Transplantation

Biomarkers have a well-defined role in the diagnosis and management of chronic heart failure, but their role in patients with left ventricular assist devices and cardiac transplant is uncertain. In this review, we summarize the available literature in this patient population, with a focus on clinical application. Some ubiquitous biomarkers, for example, natriuretic peptides and cardiac troponin, may assist in the diagnosis of left ventricular assist device complications and transplant rejection. Novel biomarkers focused on specific pathological processes, such as left ventricular assist device thrombosis and profiling of leukocyte activation, continue to be developed and show promise in altering the management of the advanced heart failure patient. Few biomarkers at this time have been assessed with sufficient scrutiny to warrant broad, universal application, but encouraging limited data and large potential for impact should prompt ongoing investigation.

A Long Noncoding RNA (lncRNA)-Associated Competing Endogenous RNA (ceRNA) Network Identifies Eight lncRNA Biomarkers in Patients with Osteoarthritis of the Knee

Background

Osteoarthritis (OA) of the knee is a common disease that is associated with chronic pain. This study aimed to identify and investigate the functional role of biomarkers associated with long noncoding RNA (lncRNA) in the progression of OA of the knee by lncRNA-associated competing endogenous RNA (ceRNA) integrated network analysis.

Material/Methods

High-quality microRNA (miRNA)-lncRNA and miRNA-mRNA interactions and lncRNA and mRNA expression profiles for patients with OA of the knee with mild and severe pain were obtained from the Gene Expression Omnibus (GEO) database (GSE99662). A three-step computational method was used to construct the lncRNA-associated ceRNA interaction network in OA by integrating miRNA-lncRNA/mRNA interactions and lncRNA/mRNA expression profiles in patients with OA with mild and severe pain.

Results

A total of 1,870 dysregulated lncRNA-mRNA interactions were obtained in the lncRNA-associated ceRNA network in OA, including 476 gain and 1,394 loss interactions, covering 131 lncRNAs and 1,251 mRNAs. Characterization of the lncRNA-associated ceRNA network in OA indicated that lncRNAs had roles in the network. Further differential expression analysis identified eight lncRNA biomarkers, which could distinguish between patients with OA with mild pain and severe pain. These lncRNA-associated interactions showed significantly different co-expression patterns in samples from patients with OA of the knee associated with mild pain.

Conclusions

Integrated network analysis of lncRNA-associated ceRNA identified eight lncRNA molecular biomarkers associated with the progression of OA of the knee.