Tachycardia

Researchers are evaluating the potential benefits of implanting an implantable cardioverter defibrillator (ICD) in patients with coronary artery disease who have survived cardiac arrest caused by ventricular fibrillation or sustained ventricular tachycardia. These patients have undergone complete revascularization and have a left ventricular ejection fraction (LVEF) above 35%. The study aims to assess whether ICD implantation can improve survival outcomes compared to standard medical therapy. Participants are randomly assigned to one of two groups: one group receives an ICD implanted either during admission or within 4 weeks after discharge from the initial cardiac event, while the other group receives guideline-directed medical therapy without ICD implantation. The study compares these approaches to understand the effect of ICDs on survival in this patient population. During the study, participants will be monitored for outcomes including all-cause mortality over a five-year period, as well as mortality related to cardiovascular causes at one year. Researchers will collect data on sudden cardiovascular death and cardiovascular death within the first year. The trial includes follow-up assessments to track these outcomes and the overall health of participants throughout the study duration.

Researchers are evaluating CRD-4730 in adults with Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT), a rare heart rhythm condition. This Phase 2, multicenter, double-blind study compares the safety, tolerability, and how the body processes and responds to CRD-4730 versus placebo. The study aims to better understand CRD-4730's effects in participants confirmed to have CPVT through genetic testing and clinical evaluation. Participants will take part in a randomized, three-period crossover trial where each individual receives two different doses of CRD-4730 and one matching placebo dose in varied sequences. The treatments are given as oral tablets over the study periods, with careful monitoring of responses. This design allows comparison of the drug’s impact at different doses and against placebo within the same participants. Throughout the study, participants will undergo exercise stress tests and other clinical assessments to measure heart rhythm changes and drug effects. Researchers will monitor safety, tolerability, and pharmacokinetics from baseline up to Day 101. Participants must maintain stable antiarrhythmic medication doses and adhere to contraceptive guidelines. The study includes detailed follow-ups to evaluate outcomes and ensure participant well-being during and after the trial.

Researchers are evaluating the safety and feasibility of a new paddle-shaped, high-density, multi-electrode mapping catheter designed to map the atrial and ventricular regions of the heart. This study focuses on patients undergoing catheter mapping and ablation procedures to manage various cardiac arrhythmias, including atrial fibrillation, atrial tachycardia, ventricular tachycardia, and premature ventricular contractions. The trial is sponsored by Biosense Webster, Inc. and aims to monitor serious and non-serious adverse events related to the investigational catheter. Participants scheduled for a clinically indicated catheter mapping and ablation procedure will have the procedure performed using the investigational mapping catheter. The catheter is designed to provide detailed mapping of heart arrhythmias to guide the ablation therapy. The study period includes the index procedure and up to seven days of follow-up to assess safety and procedural success. Physicians may use the catheter for endocardial and, if indicated, epicardial mapping during the procedure. During the study, participants will undergo the catheter mapping and ablation procedure, and researchers will evaluate the catheter's deployment, visualization, maneuverability, and signal quality. Safety is monitored by recording any serious or non-serious adverse events within seven days after the procedure. Participants must comply with all pre-, post-, and follow-up testing and requirements, with the total relevant monitoring lasting up to seven days post-procedure.

Researchers are evaluating pyridostigmine compared to a placebo for treating postural tachycardia syndrome (POTS), a condition characterized by rapid heart rate and symptoms like weakness and lightheadedness when standing. This phase 2 study aims to see if pyridostigmine can improve heart rate and stabilize blood pressure in people with POTS. The study is double-blind and placebo-controlled, meaning neither participants nor doctors know who receives the active drug or placebo during the trial. Participants will be randomly assigned to one of two groups: one taking 180 mg of time-release pyridostigmine daily, and the other taking a placebo capsule daily, both for 3 days. The study includes two visits to the outpatient General Clinical Research Center. The first visit lasts about 3 hours, and the second visit occurs 2 days later, lasting about 2 hours. During these visits, various tests and procedures assess autonomic and cardiovascular function. During each visit, participants will undergo a medical and neurological exam, height and weight measurement, and complete questionnaires about autonomic symptoms. Tests include an autonomic reflex screen with sweat gland response, cardiovascular recordings, the Valsalva maneuver, and a head-up tilt test. Blood samples will be taken to measure hormone levels while lying down and after standing. Researchers will measure changes in orthostatic symptoms using the Composite Autonomic Symptom Scale and monitor heart rate and plasma norepinephrine changes. Safety and response will be closely observed throughout the short study period.

Researchers are evaluating the safety and tolerability of a single intravenous dose of SGT-501 gene therapy in participants with catecholaminergic polymorphic ventricular tachycardia (CPVT), a rare heart condition characterized by abnormal heart rhythms triggered by exercise or stress. This Phase 1b study focuses on adults initially and includes children aged 7 to under 18 years following safety reviews by a monitoring board. The study is sponsored by Solid Biosciences Inc. and aims to gather important safety data in this first-in-human trial. Participants will receive one intravenous infusion of SGT-501 at varying doses depending on their cohort: Cohort 1 and 2 include adults aged 18 and older, while Cohort 3 includes children aged 7 to under 18 years. The dosing for children will be at or below the levels assessed in adults. The study is open-label and dose-finding, with optional dose exploration in Cohort 2. Participants will be monitored closely during the active treatment period of one year. Throughout the study, participants will be followed for a total of five years, including four years of long-term follow-up after treatment. Researchers will assess safety by tracking treatment-emergent adverse events up to 360 days post-dose. They will also evaluate changes in ventricular arrhythmia scores using exercise stress tests. Participants will undergo clinical assessments, laboratory tests, and monitoring to evaluate heart rhythm and overall health during the study and follow-up periods.

Researchers are studying atrial tachycardia (AT) that occurs after ablation of atrial fibrillation (AF) or cardiac surgery. This condition is difficult to treat due to the complex nature of the heart tissue and the mechanisms causing AT. The study aims to compare two methods of catheter ablation for AT—standard versus minimalized approaches—to see which leads to better arrhythmia-free survival. The trial is prospective, randomized, and conducted at multiple centers to improve understanding using new ultra-high-density mapping techniques. Participants will receive catheter-based ablation using radiofrequency to treat their AT. They will be randomly assigned to either a standard ablation approach or a minimalized ablation approach targeting the clinical AT. The study will evaluate various procedural details such as procedure duration, fluoroscopy time, radiofrequency application time, ablated heart area, and the number of blocked lines. Both groups will be monitored during the procedure with advanced mapping techniques to assess the underlying heart substrate and AT mechanisms. During the study, participants will undergo assessments including ECG documentation of AT, intraprocedural mapping, and evaluations of arrhythmia recurrence over one year. Researchers will measure the recurrence of sustained arrhythmia lasting more than 30 seconds as the primary outcome after one year. Other measures include inducibility of AT after ablation, predictability of secondary AT from mapping, and procedure-related parameters. Participants will be followed for safety and treatment effectiveness throughout the study period, which started in December 2020 and is expected to continue until June 2027.

Researchers are investigating the role of focal electrical activations in maintaining persistent atrial fibrillation (AF). The study evaluates a new mapping technique called RETRO-Mapping, designed to detect these focal activations during AF. This approach aims to better understand the mechanisms behind persistent AF and whether targeting these focal drivers can improve treatment outcomes compared to standard care. All participants will undergo a standard pulmonary vein isolation (PVI) procedure using advanced 3D electroanatomic mapping systems. After PVI, patients are randomly assigned to either a control group, which receives RETRO-Mapping without additional ablation, or an intervention group, where RETRO-Mapping is used to identify and ablate focal activation sites. The intervention includes mapping 30-second segments of the atria, ablating identified focal activations, and assessing changes in AF cycle length to evaluate treatment effects. Participants will be monitored through detailed intra-procedural measurements, including AF cycle length in the coronary sinus and left atrial appendage. The main outcome is the change in AF cycle length during the procedure, and a secondary outcome is freedom from AF one year after treatment. The study involves follow-up assessments and safety monitoring, with a total participation duration extending to at least one year to track long-term effects and recurrence.

Researchers are evaluating the use of Ablation Index (AI) guidance during radiofrequency catheter ablation (RFCA) for ventricular tachycardia (VT) in patients with ischemic cardiomyopathy and prior myocardial infarction. This study aims to test whether AI guidance can shorten the procedural duration compared to conventional ablation methods. The study focuses on improving lesion quality by incorporating power, contact force, and time to better estimate lesion depth during VT ablation in patients with structural heart disease. Participants will be randomly assigned to one of two groups: one receiving VT ablation guided by the Ablation Index and the other undergoing ablation without AI guidance, where AI values are masked from the operator. The AI incorporates power delivery combined with contact force and time to provide a weighted estimate of lesion quality, aiming to improve ablation precision. This trial is single-blinded and multicenter, focusing on procedural duration and safety. During the study, participants will undergo VT ablation with monitoring of procedural parameters like ablation time, total procedure duration, intravenous fluid use, and fluoroscopy time. Researchers will assess the percentage reduction in ablation time between the AI-guided and non-AI-guided groups. The study will also monitor safety and procedural efficiency. Participant involvement includes follow-up assessments as required until the study completion date in November 2027.

Researchers are investigating how accurately a smartwatch can detect heart rhythm and conduction problems in patients with cardiovascular diseases. This observational study compares the heart readings from a smartwatch to those from a traditional 12-lead electrocardiogram (ECG) to see how similar the results are and how well the smartwatch's automatic diagnosis matches expert assessments. The study aims to improve early detection and monitoring of heart conditions to prevent serious health issues. Participants will have their heart activity recorded using an Apple Watch Series 4 and a conventional ECG device. The smartwatch will record two 30-second ECG tracings while the patient is at rest, attached to the left wrist with the right hand touching the sensor to complete the measurement. The conventional ECG will capture 12 leads including a 30-second rhythm trace. The smartwatch's automatic diagnoses will be compared with the conventional ECG results and interpreted by two independent cardiologists. During the study, participants provide clinical and demographic information and undergo both smartwatch and conventional ECG recordings. The researchers will analyze the similarity of heart rate, waveforms, and intervals between methods, along with the diagnostic accuracy of atrial fibrillation and other heart rhythm disorders. The main outcome is the agreement between the smartwatch and conventional ECG diagnoses. Safety and data quality will be monitored, and participants may withdraw at any time without affecting their medical care. The total study duration is around 30 days for outcome assessment.

Researchers are studying patients with non-valvular atrial fibrillation who are scheduled to have a combined procedure involving atrial fibrillation ablation and left atrial appendage (LAA) occlusion. This prospective, multi-center, randomized controlled trial aims to compare two methods for selecting the size of the LAA occluder device during the procedure. The study is sponsored by the First Affiliated Hospital of Shantou University Medical College and seeks to evaluate the accuracy of size selection using two imaging approaches. Participants are randomly assigned to one of two groups: the CT group, where the LAA occluder size is chosen based on preoperative cardiac CT measurements, and the DSA group, where size selection is guided by intraoperative digital subtraction angiography (DSA) measurements. Both methods are used after completing the atrial fibrillation ablation. The trial measures various outcomes including the accuracy of occluder size selection during the procedure, procedural success, procedure-related times, and incidence of major adverse events within three months after the procedure. Participants will have clinical follow-ups before hospital discharge and at three months after surgery, with telephone follow-ups conducted annually for up to five years. The study monitors procedure success, device-related leaks at three months, and any major adverse events related to the device or procedure. The total participation duration can extend up to five years, allowing careful assessment of both immediate and longer-term outcomes.