Skip to main content

ASAP-TOO Clinical Trial

Is It Right for Me?
Participating in a clinical trial is a big decision. The information on this site can help you become informed on the risks and benefits, but your ultimate decision should be made with your doctor and your family. Here are some things you can consider during your discussions.

Who Can Participate in the ASAP-TOO Trial?

Boston Scientific is looking for people who:

  • Have non-valvular atrial fibrillation
  • Aren’t able to take blood thinners like warfarin (Coumadin)
  • Would be willing to have the WATCHMAN Implant
  • Would be willing to continue existing treatment if randomized to control arm (no WATCHMAN Implant)
  • Are able and willing to return for follow-up visits and exams

Talk to your doctor to see if you meet these and other qualifications

See How WATCHMAN May Help Reduce Your Risk of Stroke

What Are the Risks?

There are risks associated with the WATCHMAN device and the implant procedure. These risks include those typically related to similar types of procedures performed in the heart and those that are unique to the use of the WATCHMAN Implant.

A comprehensive list of potential risks can be found in the informed consent document you will be asked to sign prior to participating in this study. Some of the benefits and risks of participating include:

Potential Benefits
  • You could help people with atrial fibrillation who can’t take blood thinners have a new treatment option.
  • If you receive the WATCHMAN, you may have a reduced risk of stroke.
  • You’ll get ongoing, high-quality support from a cardiologist.
  • You can see the study results when they’re published.
  • You may feel like you’re part of a community of people with atrial fibrillation working together toward a better future.
  • If you’re a woman, you’ll be adding a much-needed woman’s perspective, as clinical trials typically have more male participants.
Potential Risks
  • The possible risks and side effects of taking part in this study are listed in the informed consent document. Patients who take part in this study are subject to risks that are similar to those shared by all patients who receive the commercial WATCHMAN Implant. There may also be additional risks or side effects, which are unknown at this time.
  • Complications could occur at various stages during the clinical trial, such as the test or implantation, or with the implant itself.
  • Your informed consent document details all the potential risks associated with the implant procedure and the WATCHMAN device. Be sure to review them with your doctor.

Why Would I Want to Participate?

Your participation in this study may help future patients with atrial fibrillation by helping doctors determine if the WATCHMAN device can be used in patients who cannot take blood thinners.

Doctor Discussion Guide

If you’ve been diagnosed with non-valvular atrial fibrillation, it’s important to talk to your doctor about your condition and treatment options. To help get the conversation started, bring our doctor discussion guide to your next appointment.

  • What treatment options do I have for atrial fibrillation and managing my stroke risk?
  • What is my risk of stroke?
  • Do I have to make changes to my lifestyle if I get the WATCHMAN Implant?
  • Am I a good candidate for the ASAP-TOO trial?
  • Am I a good candidate for the WATCHMAN Implant?
  • What time commitment would I have to make if I joined the ASAP-TOO trial?
  • How does the ASAP-TOO trial work?
  • What side effects should I be aware of?
  • What are the potential risks of participating in the ASAP-TOO trial?
  • How long does the procedure take?
  • How long do I need to stay in the hospital if I receive the WATCHMAN Implant?
  • How soon can I get back to my daily activities?
  • What happens if I do not receive the WATCHMAN Implant?
  • What are the potential benefits of participating in the ASAP-TOO trial?

Download and print your guide and take it with you to your next doctor appointment.

For Caregivers

If you’re caring for a loved one with atrial fibrillation, it’s important to remember that you’re not alone. In fact, more than 65 million people in the U.S. take care of someone they love due to illness, disability, or aging.1 We’re here to help with information and resources created just for you.

Caring for a loved one comes with ups, downs, rewards, and challenges. Find out how you can take charge of your role by learning more about atrial fibrillation, staying on top of medications, keeping track of doctor appointments, and more.

5 tips for caring for someone you love

1. Learn About Atrial Fibrillation

Learning more about your loved one’s condition can help you understand what they’re going through and help you provide the support and care that they need. Check out our section on atrial fibrillation and stroke risk to learn more about the condition, its symptoms, treatment options, signs of a stroke, and more.

2. Know the Signs of a Stroke

People with atrial fibrillation have a five times greater risk of stroke than those with normal heart rhythms. As a caregiver, you need to know the signs of a stroke so you can get your loved one immediate medical attention. Signs of a stroke include sudden:

  • Numbness, weakness, or paralysis of the face, arm, or leg (especially on only one side of the body)
  • Confusion
  • Trouble speaking or understanding speech
  • Difficulty seeing with one or both eyes
  • Trouble walking, dizziness, loss of balance, or lack of coordination
  • Severe headache with no known cause

3. Avoid Atrial Fibrillation Triggers

Alcohol and caffeine can trigger an atrial fibrillation episode in some people. Eliminating or reducing your loved one’s consumption of alcoholic and caffeinated beverages may help. Nicotine can also aggravate atrial fibrillation and increase the risk of coronary artery disease. So if your loved one smokes, be sure to talk to his or her doctor about ways to help your loved one quit.2

4. Discuss All the Atrial Fibrillation and Stroke Risk Treatment Options

The good news is that there are a number of treatment options out there to reduce your loved one’s risk of atrial fibrillation, stroke, and other complications, so you can keep enjoying the special moments in life together. Be sure to learn about the available treatment options and talk to your loved one and his or her doctor to find the best atrial fibrillation treatment plan for your loved one’s situation.

5. Get More Out of Doctor Appointments

Joining your loved one at doctor visits is important to show your support and make sure you’re getting all your questions answered. It can help to bring a folder to appointments or use a mobile app that keeps track of medications, symptoms, other medical conditions, appointment notes, and pharmacy and doctor contact information. To help make appointments more productive, check out our Doctor Discussion Guide.

Find an ASAP-TOO Clinical Trial Site

1 Caregiving in the U.S. 2009. National Alliance for Caregiving in Collaboration with AARP. Accessed August 13, 2015.

2 A Patient’s Guide to Living with Atrial Fibrillation. Circulation. 2008; 117: e340-e343doi: 10.1161/CIRCULATIONAHA.108.780577. Accessed August 20, 2015.


The WATCHMAN Device is a permanent implant designed to close the left atrial appendage in the heart in an effort to reduce the risk of stroke. With all medical procedures there are risks associated with the implant procedure and the use of the device. The risks include but are not limited to accidental heart puncture, air embolism, allergic reaction, anemia, anesthesia risks, arrhythmias, AV (Arteriovenous) fistula, bleeding or throat pain from the TEE (Trans Esophageal Echo) probe, blood clot or air bubbles in the lungs or other organs, bruising at the catheter insertion site, clot formation on the WATCHMAN™ Closure Device, cranial bleed, excessive bleeding, gastrointestinal bleeding, groin puncture bleed, hypotension, infection/pneumonia, pneumothorax, pulmonary edema, pulmonary vein obstruction, renal failure, stroke, thrombosis and transient ischemic attack. In rare cases death can occur. Be sure to talk with your doctor so that you thoroughly understand all of the risks and benefits associated with the implantation of the WATCHMAN Device.