Left Ventricular Assist Device

This study investigates whether metformin, compared with placebo, improves cardiac function in patients after Left Ventricular Assist Device (LVAD) implantation. Metformin is a widely used oral medication for type 2 diabetes, but emerging evidence suggests it may have beneficial effects on cardiac metabolism and function independent of its glucose-lowering effects. This is a prospective, multicenter, randomized, double-blind, placebo-controlled trial. A total of 108patients undergoing LVAD implantation will be enrolled from 5 centers in China. Eligible participants will be randomly assigned in a 1:1 ratio to receive either metformin or placebo for 12 months. The primary outcome is the incidence of Full Responder at 12 months post-implantation. A Full Responder is defined as meeting all of the following four criteria: (1) left ventricular ejection fraction (LVEF) ≥40% and left ventricular end-diastolic diameter (LVEDD) ≤6.0 cm (Utah-Inova Responder criteria); (2) soluble ST2 (sST2) ≤100 ng/mL at both 6 months and 12 months post-implantation; (3) absolute value of left ventricular global longitudinal strain (GLS) ≥12% at 12 months post-implantation. Secondary outcomes include clinical events, cardiac function status, blood biomarker results, global functional status and quality of life, medication safety, and exploratory measures. Clinical events assessed up to 24 months post-implantation include: heart failure rehospitalization rate, all-cause mortality, LVAD explantation rate, cardiovascular mortality, major bleeding, cardiac structural damage, thromboembolic events, systemic inflammatory dissemination, sepsis, and other serious adverse events. Cardiac function status is evaluated by echocardiographic parameters (LVEF, LVEDD, GLS) and hemodynamic measures. Blood biomarkers include sST2, NT-proBNP, cardiac troponin, and inflammatory cytokines. Global functional status and quality of life are measured using the 6-minute walk test (6MWT), peak oxygen consumption (VO₂max), and the Kansas City Cardiomyopathy Questionnaire (KCCQ). Safety outcomes include the incidence and severity of adverse events, serious adverse events, and adverse events of special interest. Exploratory outcomes include pre-implantation right ventricular myocardial biopsy (obtained only when clinically indicated for temporary pacemaker lead placement) to assess insulin receptor substrate (IRS)/Akt phosphorylation, G6PD activity, NADPH/NADP⁺ ratio, and oxidative stress markers (malondialdehyde, 4-hydroxynonenal). The study aims to provide evidence on whether adjunctive metformin therapy can improve post-LVAD cardiac outcomes and reduce adverse clinical events.

Current international guidelines recommend that patients with a heart pump (left ventricular assist device, LVAD) participate in supervised exercise cardiac rehabilitation programs. However, not all patients with a heart pump are able to attend to a supervised program on a daily basis. The goal of this clinical trial is to determine whether a home-based exercise program helps patients with a heart pump improve their exercise capacity and quality of life, guided by telemedicine tools including a mobile app, smartwatch, and remote medical checkups. The study will also provide information about the safety of this program by monitoring for any issues or symptoms during home activity. The trial aims to answer the following questions: * Does a 12-week remote exercise program improve patients' exercise capacity? This will be measured using the 6-minute walk test and a cardiopulmonary exercise test. * Is it safe for patients to follow this exercise plan at home while being monitored through a mobile app and smartwatch? * Does the program improve quality of life and reduce feelings of anxiety or depression? This will be assessed using widely validated questionnaires, such as the Kansas City Cardiomyopathy Questionnaire. Researchers will compare the remote exercise program to standard care, which usually does not include exercise for patients who are unable to attend the hospital daily. Participants will: * Join the study voluntarily after signing a consent form. * Be randomly assigned, with a 50% chance of being in either the exercise group (following a structured plan with a mobile app) or the usual care group (receiving general written advice), to see which approach works best for recovery. * Follow a 12-week home-based routine if in the exercise group, including warm-up routine, walking or cycling, respiratory exercises, and light strength training, all supported by the mobile app, smartwatch, and professional monitoring. * Visit the hospital three times over six months for medical checkups, including walking and exercise tests, blood analyses, and questionnaires about physical and emotional health.

Background: While left ventricular assist device (LVAD) therapy improves survival in patients with advanced heart failure (AHF), unique LVAD-related burdens may impact health-related quality of life (HRQoL). Palliative care specialists are key members of the multidisciplinary care team for patients with long-term-LVAD (LT-LVAD), offering specialized, comprehensive, holistic care. Problem: A seminal study of palliative care in patients with heart failure (PAL-HF trial) demonstrated that outpatient palliative care improved HRQoL, depression, anxiety, and spiritual well-being compared to usual care. The impact of longitudinal palliative care on HRQoL in LT-LVAD patients is unknown. Objective: The investigators aim to conduct the first study examining a palliative care intervention to improve HRQoL among LT- LVAD recipients (patients who have lived with LT-LVAD for at least six months and are not heart transplant candidates) at two centers (MedStar Health and Inova) in the Mid-Atlantic Region. Given the demographics of the study institutions, the investigators anticipate a socioeconomically and racially diverse cohort of patients with subgroups who may disproportionately experience LVAD-related burdens relative to benefits. Aims: The first aim is to assess baseline measures of HRQoL in LT-LVAD patients to understand differences in HRQoL across subgroups and multiple, understudied domains. The second aim is to test the feasibility and acceptability of a randomized, unblinded pilot study of a palliative care interdisciplinary intervention in this population. Significance: Results of this study will inform the development of a large randomized controlled trial to test the effectiveness of palliative care intervention in improving HRQoL in LT-LVAD patients. If results are positive, this will revolutionize the post-LVAD treatment paradigm, by making palliative care integration the standard of care for longitudinal LT-LVAD patient management.

CASTLE-VT is a randomized evaluation of prophylactic ablative treatment of arrhythmogenic ventricular scar in patients referred for HTx evaluation and diagnosed with ICM. Ablation will be performed with the use of a substrate-based approach in which the myocardial scar is mapped and ablated while the heart remains predominantly in sinus rhythm. The primary end point is the composite of all-cause mortality, worsening of HF requiring prioritized transplantation or LVAD implantation. The main secondary study end points are all-cause mortality, cardiovascular mortality, incidence of implantable cardioverter-defibrillator (ICD) therapy, hospitalizations, Quality of life, time to first ICD therapy, number of device-detected ventricular tachycardia/ventricular fibrillation episodes, LV function, and exercise tolerance. CASTLE-VT will randomize 160 patients with a follow up period of 2 years.

A biobank has been created to investigate the prognostic value of biomarkers (mainly BNP) in patients implanted with durable mechanical assist devices comparing patients with advanced HF supported by MCS with those who are transplanted and those who remain on optimal medical therapy. Patients will be followed up for 25 years after inclusion.