NCT05724121 · National Heart, Lung, and Blood Institute (NHLBI)
Observational Study of Cardiac Arrhythmias During Treatment With BTK Inhibitors or Venetoclax
What this study is about
Background: Bruton s tyrosine kinase inhibitors (BTKi) are used to treat a form of leukemia. But taking BTKi can also increase a person s risk of developing an abnormal heart rhythm. This can cause sudden death. In this natural history study, researchers want to learn how BTKi affects the heart. Objective: To identify and monitor the effects of BTKi on the heart.
View original scientific description
Background: Bruton s tyrosine kinase inhibitors (BTKi) are used to treat a form of leukemia. But taking BTKi can also increase a person s risk of developing an abnormal heart rhythm. This can cause sudden death. In this natural history study, researchers want to learn how BTKi affects the heart. Objective: To identify and monitor the effects of BTKi on the heart. Eligibility: People aged 18 and older currently receiving or planning to receive BTKi or venetoclax. Design: Participants who have not yet started BTKi will have 2 required clinic visits: 1 before they start taking BTKi, and 1 about 6 months later. Participants who are already taking BTKi will have 1 required visit. Participants will undergo multiple tests: A physical exam, including collection of blood and saliva. A test that measures heart activity via stickers placed on the chest. A test that uses sound waves to capture images of the heart. An exercise stress test that monitors heart activity and blood pressure while the participant works on a treadmill or stationary bike. Sound wave images of the heart may also be taken while the participant exercises. Stress magnetic resonance imaging (MRI) may be done in place of an exercise test. Participants will lie on a table that slides into a tube. They will be given drugs to stress the heart while images are taken. Participants may wear a device to monitor their heart at home. Participants may have repeat visits if they develop heart symptoms or if they need to stop taking BTKi. They will have follow-up phone calls each year for up to 3 years.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- To be eligible to participate in this study, an individual must meet all of the following criteria:
- Currently receiving or planning to receive a BTKi or venetoclax.
- Male or female, aged 18 or older
- Stated willingness to comply with all study procedures and availability for the duration of the study
- Ability of subject to understand and the willingness to sign a written informed consent document
Exclusion criteria
- An individual who meets any of the following criteria will be excluded from participation in this study:
- Any acute cardiac condition including myocardial infarction or decompensated heart failure within the past 3 months
- Pregnancy or lactation- use of BTK inhibitors is contraindicated in pregnant or nursing individuals.
Where
- Bethesda, Maryland
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 2, 2026 · Source of record for eligibility and locations