Clinical Research Directory

Catheter Ablation Versus Anti-arrhythmic Drugs for Ventricular Tachycardia

Sudden cardiac death (SCD) due to recurrent ventricular tachycardia (VT) is an important clinical sequela in patients with structural heart disease. VT generally occurs as a result of electrical re-entry in the presence of arrhythmogenic substrate (scar). Scar tissue forms due to an ischemic cardiomyopathy (ICM) from prior coronary obstructive disease or a non-ischemic cardiomyopathy (NICM) from an inflammatory or genetic disease. AADs can reduce VT recurrence, but have significant limitations in treatment of VT. For example, amiodarone has high rates of side effects/toxicities and a finite effective usage before recurrence. ICDs prevent cardiac arrest and sudden death from VT, but do not stop VT occurring. Recurrent VT and ICD therapies decrease QOL, increase hospital visits, mortality, morbidity and risk of death. Improvement in techniques for mapping and ablation of VT have made CA an alternative. Currently, there is limited evidence to guide clinicians either toward AAD therapy or CA in patients with NICM. This data shows significant benefit of CA over medical therapy in terms of VT free survival, survival free of VT storm and VT burden. Observational studies suggest that CA is effective in eliminating VT in NICM patients who have failed AADs, resulting in reduction of VT burden and AAD use over long term follow up. Furthermore, there is limited data on the efficacy of CA in early ICM with VT, or advanced ICM with VT. RCT data is almost exclusively on patients with modest ICM with VT, and this is not representative of the real-world scenario of patients with structural heart disease presenting with VT. Therefore the primary objective is to determine in all patients with structural heart disease and spontaneous or inducible VT, if catheter ablation compared to standard medical therapy with anti-arrhythmic drugs results in a reduction of a composite endpoint of recurrent VT, VT storm and death at a median follow up of 18 months.

National Network for Cardiovascular Genomics: Advancing Cardiovascular Healthcare for Hereditary Diseases in Brazil's Unified Health System Through a Multicenter Registry

The goal of this observational study is to develop a registry of Brazilian patients with hereditary cardiovascular diseases, combining clinical and genomic data. The main questions it aims to answer are: Which genes are most commonly affected? What is the frequency of these genetic alterations in our population? Participants will be interviewed in routine medical care visits and their DNA will be sequenced.

Mavacamten Enables Exercise in Hypertrophic Obstructive Cardiomyopathy

Patients with hypertrophic obstructive cardiomyopathy and New York Heart Association Class I-II under stable treatment with mavacamten (at least 12 weeks without change of dosage) and a peak left ventricular outflow tract obstruction \<50mmHg undergo either 6 weeks of structured moderate intensity endurance and resistance training (supervised, 3x/week, intervention, IT) or usual care (UC). Patients within 1 hour of travel to the training venue will be referred to IT, while those with more than 1 hour will join UC. At baseline (visit 1, V1) and after 6 weeks of exercise intervention (visit 2, V2) all patients undergo a medical exam, resting and stress echocardiography and receive a questionnaire on the quality of life (Kansas City Cardiomyopathy Questionnaire). Cardiac biomarkers are assessed. 3 hours after stress echocardiography cardiopulmonary exercise testing is performed to measure peak oxygen consumption (VO2peak). The primary outcome is safety. Secondary outcomes include the change of VO2peak, changes in cardiac biomarkers, resting and stress echocardiographic variables, quality of life and variables of cardiopulmonary exercise testing from V1 to V2.

A Study to Evaluate Mavacamten in Adolescents With Symptomatic Obstructive Hypertrophic Cardiomyopathy

The purpose of this study is to evaluate the efficacy, safety, and pharmacokinetics of mavacamten in adolescent patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM).

Analysis of Lumbar Spine Stenosis Specimens for Identification of Transthyretin Cardiac Amyloidosis

Primary objective: To identify older adults with transthyretin cardiac amyloidosis (ATTR-CA) early in the course of the illness, at a time when disease modifying therapies are most effective. The specific aims of this epidemiologic investigation include: 1. To identify subjects with previous lumbar spinal stenosis (LSS) Surgery who have evidence of transthyretin (TTR) amyloid deposits in spinal specimens and could be at risk for ATTR cardiac amyloidosis. 2. To evaluate for ATTR-CA among those with localized TTR in the spinal tissue. The study will also explore the following: 1. The prevalence of amyloid in lumbar spinal stenosis specimens by Congo Red staining. 2. The prevalence of TTR deposits among subjects with amyloid as determined by mass spectrometry. 3. Evaluation of a novel artificial intelligence technique for that can identify amyloid histologically with standard H\&E staining. 4. Difference in ATTR-CA prevalence between subjects with TTR and indeterminate amyloid deposits in subject's spine by myocardial uptake of technetium pyrophosphate scan (Tc99-PYP).

A Study to Evaluate Mavacamten Impact on Myocardial Structure in Participants With Symptomatic Obstructive Hypertrophic Cardiomyopathy

The purpose of this study is to evaluate the mavacamten impact on myocardial structure with cardiac magnetic resonance imaging (CMR) in adult participants with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) \[New York Heart Association (NYHA) Functional Class II or III\].

Effect of an Aerobic Exercise Session on Cardiovascular and Autonomic Parameters of Adults With Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy is a genetic heart disease with symptoms that may include dyspnea and fatigue predominantly on exertion, with or without chest pain, palpitations, syncope/presyncope and sudden cardiac death, mostly in young individuals, often without symptoms. Due to the higher cardiovascular risk described for individuals with hypertrophic cardiomyopathy, it is extremely important to create non-pharmacological strategies that can minimize the evolution of cardiovascular risk factors found in this population. The objective of the study will be to evaluate the effect of an aerobic exercise session on the ratio between the low frequency (LF) and high frequency (HF) bands of heart rate variability, endothelial function through flow-mediated dilation and systolic and diastolic blood pressure during the 24-hour period in adult individuals with hypertrophic cardiomyopathy. The study design will be a randomized crossover clinical trial with individuals aged 18 to 59 years, of both sexes, randomized by lottery and divided into two groups: Exercise group and control group without exercise. An exercise stress test will be performed and on a new date the individuals will perform a supervised session of moderate-intensity aerobic exercise on a horizontal stationary bicycle for 50 minutes or will remain seated in an air-conditioned room for the same period of time. Subsequently, the procedures will be crossed. It is expected to find improvements in the parameters of endothelial function, autonomic modulation and 24-hour blood pressure in adult individuals with non-obstructive hypertrophic cardiomyopathy undergoing a session of aerobic physical exercise when compared to a control session without exercise.

Concomitant Hybrid Versus Catheter Ablation for Atrial Fibrillation With Hypertrophic Cardiomyopathy

The goal of this clinical trial is to compare the rhythm control effect in hypertrophic non-obstructive patients with non-paroxysmal atrial fibrillation by either concomitant catheter endocardial and thoracoscopic epicardial ablation or catheter ablation alone. The study aims to see if concomitant hybrid ablation can more effectively achieve rhythm control effect than catheter ablation alone in non-paroxysmal atrial fibrillation patients with hypertrophic cardiomyopathy.

The Chinese Hypertrophic Cardiomyopathy Study(CHCS)

Hypertrophic cardiomyopathy (HCM) is one of the most common inherited cardiac diseases, with a prevalence of ∼0.2%. Sudden cardiac death (SCD), heart failure and stroke are the major poor outcomes of HCM. Although about half of the patients were found to be caused by mutations mainly located in genes encoding sarcomere proteins, the causes in a significant proportion of patients with HCM are still unknown. Even in the patients with sarcomere mutations, the molecular pathways that eventually lead to cardiac hypertrophy are remained to be revealed. Furthermore, HCM presents with significant heterogeneity. SCD risk stratification and prevention by ICD are necessary. However, the strategy of SCD risk stratification recommended by the 2011 ACCF/AHA and 2014 ESC guidelines were based mainly on the evidence derived from American and European countries. The accuracy of these guidelines in Chines patients with HCM was not evaluated yet.