Cardiac resynchronization therapy and outcomes in patients with left ventricular assist devices: a systematic review and meta-analysis

Digital Biomarker-Based Interventions: Systematic Review of Systematic Reviews

BACKGROUND

The introduction of new medical technologies such as sensors has accelerated the process of collecting patient data for relevant clinical decisions, which has led to the introduction of a new technology known as digital biomarkers.

OBJECTIVE

This study aims to assess the methodological quality and quality of evidence from meta-analyses of digital biomarker-based interventions.

METHODS

This study follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline for reporting systematic reviews, including original English publications of systematic reviews reporting meta-analyses of clinical outcomes (efficacy and safety endpoints) of digital biomarker-based interventions compared with alternative interventions without digital biomarkers. Imaging or other technologies that do not measure objective physiological or behavioral data were excluded from this study. A literature search of PubMed and the Cochrane Library was conducted, limited to 2019-2020. The quality of the methodology and evidence synthesis of the meta-analyses were assessed using AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews 2) and GRADE (Grading of Recommendations, Assessment, Development, and Evaluations), respectively. This study was funded by the National Research, Development and Innovation Fund of Hungary.

RESULTS

A total of 25 studies with 91 reported outcomes were included in the final analysis; 1 (4%), 1 (4%), and 23 (92%) studies had high, low, and critically low methodologic quality, respectively. As many as 6 clinical outcomes (7%) had high-quality evidence and 80 outcomes (88%) had moderate-quality evidence; 5 outcomes (5%) were rated with a low level of certainty, mainly due to risk of bias (85/91, 93%), inconsistency (27/91, 30%), and imprecision (27/91, 30%). There is high-quality evidence of improvements in mortality, transplant risk, cardiac arrhythmia detection, and stroke incidence with cardiac devices, albeit with low reporting quality. High-quality reviews of pedometers reported moderate-quality evidence, including effects on physical activity and BMI. No reports with high-quality evidence and high methodological quality were found.

CONCLUSIONS

Researchers in this field should consider the AMSTAR-2 criteria and GRADE to produce high-quality studies in the future. In addition, patients, clinicians, and policymakers are advised to consider the results of this study before making clinical decisions regarding digital biomarkers to be informed of the degree of certainty of the various interventions investigated in this study. The results of this study should be considered with its limitations, such as the narrow time frame.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/28204.

Another Strike Against Continuing Cardiac Resynchronization Therapy in Left Ventricular Assist Device recipients?

Continuous flow left ventricular assist devices (LVAD) are an important therapeutic strategy, either as a bridge to transplant, bridge to recovery or as destination therapy, in patients with end-stage heart failure. This article is protected by copyright. All rights reserved.

Association Between Biventricular Pacing and Incidence of Ventricular Arrhythmias in the Early Post-Operative Period after Left Ventricular Assist Device Implantation

INTRODUCTION

Cardiac resynchronization therapy (CRT) and left ventricular assist devices (LVAD) improve outcomes in heart failure patients. Early ventricular arrhythmias (VA) are common after LVAD and are associated with increased mortality. The association between left ventricular pacing (LVP) with CRT and VAs in the early post-LVAD period remains unclear.

METHODS

This was a retrospective study of all patients undergoing LVAD implantation from 1/2016 - 12/2019. Patients were divided into those with CRT and active LVP (CRT-LVP) immediately post-LVAD implant versus those without CRT-LVP. ICD electrograms were reviewed and early VAs were defined as sustained VT/VF occurring within 30 days of LVAD implantation.

RESULTS

Of 186 included patients (mean age 53 years, 75% male, mean BMI 28), 72 had CRT devices, 63 of whom had LV pacing enabled after LVAD implant (CRT-LVP group). Patients with CRT-LVP were more likely to have VA in the early post-operative period (21% vs 4%; p=0.0001). All 9 patients with CRT in whom LVP was disabled had no early VA. Among those with early VA, patients with CRT-LVP were more likely to have monomorphic VT (77% vs 40%; p=0.07). In multiple logistic regression, CRT-LVP pacing remained an independent predictor of early VA after adjustment for history of VA and AF.

CONCLUSIONS

Patients with CRT-LVP after LVAD implant had a higher incidence of early VA (specifically monomorphic VT). Epicardial LV pacing may be proarrhythmic in the early post-operative period after LVAD. This article is protected by copyright. All rights reserved.

Impact of Race on Clinical Outcomes After Implantation With a Fully Magnetically Levitated Left Ventricular Assist Device: An Analysis From the MOMENTUM 3 Trial

BACKGROUND

Heart failure disproportionately affects Black patients. Whether differences among race influence outcomes in advanced heart failure with use of a fully magnetically levitated continuous-flow left ventricular assist device remains uncertain.

METHODS

We included 515 IDE (Investigational Device Exemption) clinical trial patients and 500 Continued Access Protocol patients implanted with the HeartMate 3 left ventricular assist device in the MOMENTUM 3 study (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3). Outcomes were compared between Black and White left ventricular assist device recipients for the primary end point of survival free of disabling stroke or reoperation to replace or remove a malfunctioning device at 2 years, overall survival, adverse events, 6-minute walk distance, and quality of life scores.

RESULTS

Of 1015 HeartMate 3 patients, 675 were self-identified as White and 285 as Black individuals. The Black patient cohort was younger, more obese and with a history of hypertension, and more nonischemic cause of heart failure, relative to the White patient group. Black and White patients did not experience a difference in the primary end point (81.1% versus 77.9%; hazard ratio, 1.08 [95% CI, 0.76-1.54], P=0.6568). Black patients were at higher risk of adverse events (calculated as events per 100 patient-years), including bleeding (75.4 versus 63.5; P<0.0001), stroke (9.5 versus 7.2; P=0.0183), and hypertension (10.1 versus 3.2; P<0.0001). The 6-minute walk distance was not different at baseline and 6 months between the groups, however, the absolute change from baseline was greater for White patients (median: +183.0 [interquartile range, 42.0-335.3] versus +163.8 [interquartile range, 42.3-315.0] meters, P=0.01). The absolute quality of life measurement (EuroQoL group, 5-dimension, 5-level instrument visual analog scale) at baseline and 6 months was better in the Black patient group, but relative improvement from baseline to 6 months was greater in White patients (median: +20.0 [interquartile range, 5.0-40.0] versus +25.0 [interquartile range, 10.0-45.0]; P=0.0298).

CONCLUSIONS

Although the survival free of disabling stroke or reoperation to replace/remove a malfunctioning device at 2 years with the HM 3 left ventricular assist device did not differ by race, Black HeartMate 3 patients experienced a higher morbidity burden and smaller gains in functional capacity and quality of life when compared with White patients. These findings require efforts designed to better understand and overcome these gaps through systematic identification and tackling of putative factors. Registration: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02224755 and NCT02892955.

Biventricular Pacing Versus Right Ventricular Pacing in Patients Supported With LVAD

OBJECTIVES

This study sought to evaluate the effects of right ventricular (RV) pacing versus biventricular (BiV) pacing on quality of life, functional status, and arrhythmias in LVAD patients.

BACKGROUND

Cardiac resynchronization therapy (CRT) and left ventricular assist devices (LVADs) independently improve outcomes in heart failure patients, but the effects of combining these therapies remains unknown. We present the first prospective randomized study evaluating the effects of RV versus BiV pacing on quality of life, functional status, and arrhythmias in LVAD patients.

METHODS

In this prospective randomized crossover study, LVAD patients with prior CRT devices were alternated on RV and BiV pacing for planned 7-14-day periods. Ambulatory step count, 6-minute walk test distance, Kansas City Cardiomyopathy Questionnaire scores, arrhythmia burden, CRT lead function, and echocardiographic data were collected with each pacing mode.

RESULTS

Thirty patients were enrolled, with a median age of 65 years, 67% male, and mean duration of LVAD support of 309 days. Compared with BiV pacing, RV-only pacing resulted in 29% higher mean daily step count, 11% higher 6-minute walk test distance, and 7% improved KCCQ-12 score (all p < 0.03). LV end-diastolic volume was significantly lower with RV pacing (220 vs. 250 mL; p = 0.03). Fewer patients had ventricular tachyarrhythmia episodes during RV pacing (p = 0.03). RV lead impedance was lower with RV pacing (p = 0.047), but no significant differences were observed in impedance across other CRT leads.

CONCLUSIONS

In the first prospective randomized study comparing variable pacing in LVAD patients, RV pacing was associated with significantly improved functional status, quality of life, fewer ventricular tachyarrhythmias, and stable lead impedance compared with BiV pacing. This study supports turning off LV lead pacing in LVAD patients with CRT.

Continued versus Suspended Cardiac Resynchronization Therapy after Left Ventricular Assist Device Implantation

Cardiac resynchronization therapy (CRT) improves outcomes in heart failure patients with wide QRS complex. However, CRT management following continuous flow Left Ventricular Assist Device (LVAD) implant vary: some centers continue CRT while others turn off the left ventricular (LV) lead at LVAD implant. We sought to study the effect of continued CRT versus turning off CRT pacing following continuous flow LVAD implantation. A comprehensive retrospective multicenter cohort of 295 patients with LVAD and pre-existing CRT was studied. CRT was programmed off after LVAD implant in 44 patients. We compared their outcomes to the rest of the cohort using univariate and multivariate models. Mean age was 60 ± 12 years, 83% were males, 52% had ischemic cardiomyopathy and 54% were destination therapy. Mean follow-up was 2.4 ± 2.0 years, and mean LVAD support time was 1.7 ± 1.4 years. Patients with CRT OFF had a higher Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) mean profile (3.9 vs 3.3, p = 0.01), more secondary prevention indication for a defibrillator (64.9% vs 44.5%, p = 0.023), and more pre-LVAD ventricular arrhythmias (VA) (77% vs 60%, p = 0.048). There were no differences between the CRT OFF and CRT ON groups in overall mortality (Log rank p = 0.32, adjusted HR = 1.14 [0.54-2.22], p = 0.71), heart transplantation, cardiac and noncardiac mortality, all cause hospitalizations, hospitalizations for ICD shocks, and number and frequency of ICD shocks or anti-tachycardia pacing therapy. There were no differences in post LVAD atrial arrhythmias (AA) (Adjusted OR = 0.45 [0.18-1.06], p = 0.31) and ventricular arrhythmias (OR = 0.65 [0.41-1.78], p = 0.41). There was no difference in change in LVEF, LV end diastolic and end systolic diameters between the 2 groups. Our study suggests that turning off CRT pacing after LVAD implantation in patients with previous CRT pacing did not affect mortality, heart transplantation, device therapies or arrhythmia burden. A prospective study is needed to confirm these findings.