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59 active trials for Ventricular Tachycardia

Cohort Study - SBRT for VT Radioablation

Ventricular tachycardia (VT) contributes to over 350,000 sudden deaths each year in the US. Malignant VTs involve an electrical "short circuit" in the heart, formed by narrow channels of surviving tissue inside myocardial scar. Current treatment for VT consists of either implantable defibrillators (ICDs), suppressive drug therapy, catheter ablation or a combination of all 3. Implantable Defibrillators (ICDs) reduce sudden death and can terminate some ventricular tachycardia (VT) without shocks, but they don't prevent VT. The occurrence of ?1 ICD shock is associated with reductions in mental well-being and physical functioning, and increases in anxiety and sometimes depression. Further, ICD shocks have been consistently associated with adverse outcomes, including heart failure and death. Furthermore, the most important predictor of ICD shocks is a history of prior ICD shocks. Therapies to suppress VT include antiarrhythmic drug therapy and catheter ablation, neither however is universally effective. When VT recurs despite antiarrhythmic drug therapy and catheter ablation, novel yet invasive, approaches may be required. Such invasive procedures carry consequent risks of cardiac and extra-cardiac injury. Stereotactic body radiotherapy (SBRT) is a non-invasive technique that delivers high doses of radiation precisely to specified regions in the body, while minimizing exposure to adjacent tissue. This technique is currently, and commonly used in the treatment of cancer. Conventional application of SBRT has made use of its ability to spare non-target tissue, including for treatment of tumors near the heart. More recently, clinicians have changed the paradigm, by focusing radioablative energy on ventricular scar responsible for ventricular tachycardia. Pre-clinical studies have supported the concept and were followed by first-in-human VT therapeutic experience in 2017. Subsequent studies have had encouraging results for patients who failed or were unable to tolerate conventional treatment.

Start: March 2021
Peri-Procedural Transmural Electrophysiological (EP) Imaging of Scar-Related Ventricular Tachycardia

Ventricular tachycardia (VT) contributes to over 350,000 sudden deaths each year in the US. Malignant VTs involve an electrical "short circuit" in the heart, formed by narrow channels of surviving tissue inside myocardial scar. An important treatment is to use catheter ablation to "block" the channel that forms the circuit. Effective ablation requires imaging guidance to visualize the VT circuit relative to scar structures in 3D. Unfortunately, with conventional catheter mapping, up to 90% of the VT circuits are too short-lived to be mapped. For the 10% "mappable" VTs, their data are only available during ablation and limited to one ventricular surface. This inadequacy of functional VT data largely limits the knowledge about scar-related VT and ablation strategies, and reduces the ability of clinicians to identify ablation targets and assess ablation outcome. The central hypothesis of this proposal is that functional VT data, integrated with CT or MRI scar data in 3D, can improve VT ablation efficacy with pre-procedural identification of ablation targets and post-procedural mechanistic elucidation of ablation failure. This research builds on the rapidly increasing clinical interest in electrocardiographic imaging (ECGi), an emerging technique that obtains cardiac electrical activity through inverse reconstructions from ECGs. The specific objective is to push the boundary of ECGi to provide - as a conjunction to intra-procedural catheter mapping - pre-ablation and post-ablation imaging of functional VT circuits integrated with 3D scar structure.

Start: November 2019
Cardiopulmonary Resuscitation Performance of Professional Rescuers With a New Defibrillation Algorithm

In the Paris (France) Medical Emergency system, in the early phase of Out-of-hospital Cardiac Arrest (OHCA), the treatment of a Ventricular Fibrillation (VF) consists of delivering an External Electric Shock (EES) by a rescuer with the use of an Automated External Defibrillator (AED). This latter realizes a cardiac rhythm analysis every two minutes. This analysis requires that chest compressions (CC) be interrupted for a while. However, CC interruptions are potentially harmful due to the brain, and heart perfusions decrease. On the other hand, the recurrence of VF occurs mostly during the first minute after the shock, whereas the delay between 2 rhythm analysis is 2 minutes. The consequence is excessive time spent in VF, which is deleterious in terms of coronary and cerebral perfusion. The investigator implements a new AED algorithm whose operating principle is as follows. One minute after an EES administration, the AED realizes a cardiac rhythm analysis during which the rescuers do not need to interrupt the chest compressions (CC): this is called the rhythm analysis " in presence of CC" The detection of a VF " in presence of CC " needs to be confirmed, " in absence of CC " The CC's are therefore interrupted for new rhythm analysis. Once the presence of VF is approved, the AED proposes a shock to be administred The aim of the study Study Design: This is a prospective observational study. The eligibility criteria are as follows: Patients in Out-Of-Hospital Cardiac Arrest. Basic Life support care with an AED. The primary endpoint is the " chest-compression fraction (CCF) " that represents the CPR-time performance during the ten first minutes of BLS care ( or < 10 min in case of Return Of Spontaneus Circulation (ROSC))

Start: January 2021
Multimodality Assessment of Ventricular Scar Arrhythmogenicity.

We aim to improve our understanding of a life-threatening heart rhythm disorder known as ventricular tachycardia (VT). This is a disorder which originates from the lower chamber of the heart and frequently is associated with heart disease. We will use an MRI scan to generate a computer based model of the heart which can predict areas of the heart which are important in generating this rhythm disorder. We intend to assess how accurate this computer model is compared to traditional invasive assessment of the heart muscle. We also aim to assess the electrical characteristics of those areas which were predicted by the computer model in order to see why they were thought to be so important. All patients seen at St George's Hospital with VT will be eligible. As is routine for these patients, they will have an MRI scan of the heart. We will then use this scan to create a virtual reconstruction of the heart from which predictions of the critical areas of the heart which are generating the rhythm problem will be made. Then we will perform a VT ablation (studying the electrical properties and if necessary making a burn to treat the rhythm problem) - as per standard of care, however during the ablation we will spend extra time collecting information comparing the accuracy of the computer-generated model to the traditional invasive signals which guide ablation. We will study the electrical properties of those predicted areas to see what is special about them. The study will last up to three years.

Start: December 2020
CMR Based Prediction of Ventricular Tachycardia Events in Healed Myocardial Infarction (DEVELOP-VT)

Fibrotic tissue is known to be the substrate for the appearance of scar-related reentrant ventricular arrhythmias (VA) in chronic ischemic cardiomyopathy (ICM). Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) has proven to be a useful technique in the non-invasive characterization of the scarred tissue and the underlying arrhythmogenic substrate. Previous studies identified the presence of significant scarring (> 5% of the left ventricular -LV- mass) is an independent predictor of adverse outcome (all-cause mortality or appropriate ICD discharge for ventricular tachycardia or fibrillation) in patients being considered for implantable cardioverter-defibrillator (ICD) placement. Parallelly, the presence of heterogeneous tissue channels, which correlate with voltage channels after endocardial voltage mapping of the scar, can be more frequently observed in patients suffering from sustained monomorphic ventricular tachycardias (SMVT) than in matched controls for age, sex, infarct location, and left ventricular ejection fraction (LVEF). However, the lack of solid evidence and randomized trials make LVEF still the main decision parameter when assessing suitability for ICD implantation in primary prevention of sudden cardiac death (SCD). In a recent, case-control study, we identified the border zone channel (BZC) mass as the only independent predictor for VT occurrence, after matching for age, sex, LVEF and total scar mass. This BZC mass can be automatically calculated using a commercially available, post-processing imaging platform named ADAS 3D LV (ADAS3D Medical SL, Barcelona, Spain), with FDA 510(k) Clearance and CE Mark approval. Thus, CMR-derived BZC mass might be used as an automatically reproducible criterium to reclassify those patients with chronic ICM at highest risk for developing VA/SCD in a relatively short period of approx. 2 years. In the present cohort study, we sought to evaluate the usefulness of the BZC mass measurement to predict the occurrence of VT events in a prospective, multicenter, unselected series of consecutive chronic ischemic patients without previous arrhythmia evidence, irrespectively of their LVEF.

Start: August 2020
Observational and Diagnostical Study on Transient Allostatic Responses of Thyroid Function After Cardiopulmonary Resuscitation

Time-limited adaptive responses of thyroid function are common in the critically ill. About 70% of all patients treated on intensive care units develop a so-called non-thyroidal illness syndrome (NTIS) or TACITUS (thyroid allostasis in critical illness, tumours, uraemia and starvation), which is marked by low serum concentrations of the thyroid hormone T3 and other adaptive reactions of thyroid homeostasis. Occasionally, temporarily elevated concentrations of thyrotropin (TSH) and peripheral thyroid hormones are to be observed, especially after cardiopulmonary resuscitation (CPR). However, the available evidence is limited, although abnormal concentrations of thyroid hormones after CPR have occasionally been reported. Aim of the planned study is to investigate the thyrotropic (i.e. thyroid-controlling) partial function of the anterior pituitary lobe immediately after CPR. It is intended to evaluate statistical measures of TSH concentration and peripheral thyroid hormones in de-identified datasets (protocol A). Additionally, a prospective sub-study (protocol B) aims at a more precise description of pituitary and thyroid responses by means of serial investigations in routine serum samples, both immediately after CPR and during the course of ongoing treatment. This includes the evaluation of additional possible predictors, too. Primary endpoint of the study is changed TSH concentration immediately after CPR compared to the TSH value 24 hours later. Secondary endpoint is the relation between thyroid-controlling pituitary function and mortality. A high proportion of patients undergoing CPR will eventually receive iodinated radiocontrast media (e.g. for computed tomography or coronary angiography). This is one of the reasons why early identifying subjects at high risk for possible iodine-induced thyrotoxicosis is important. Increased oxygen consumption of the heart in hyperthyroidism is one of the reasons for high mortality in thyrotoxicosis. Therefore, accurate diagnosis of alterations in the hypothalamus-pituitary-thyroid (HPT) axis is of paramount importance.

Start: November 2020