RecruitingPHASE3INTERVENTIONAL

Low INR to Minimize Bleeding With Mechanical Valves Trial

This study is investigating if a lower dose of warfarin, a common blood-thinning medicine, can be safely used by people who have a mechanical heart valve in the main artery (aorta). Currently, people with these valves need warfarin to prevent dangerous blood clots, but this also increases the risk of bleeding. The study aims to find out if keeping your blood thinner level (called INR) between 1.5 and 2.5 can reduce bleeding without making blood clots or strokes more likely. The results could help doctors give safer recommendations for patients with mechanical heart valves, potentially lowering their risk of serious bleeding events while still protecting them from clots.

At a glance

Status

Recruiting

Phase

PHASE3

Sponsor

Population Health Research Institute

Enrolment target

2,625

Start

05 Sep 2019

Estimated completion

31 Dec 2026

Bleeding Post-mechanical Valve Replacement Thromboembolism Post-mechanical Valve Replacement

What is this study about?

If you have a mechanical heart valve, you'll know that you need to take a medicine called warfarin for life. This is a blood-thinning medicine that helps stop blood clots from forming on your new valve. Blood clots can be very dangerous if they travel to your brain (causing a stroke), heart, or other parts of your body.

Now, the challenge with warfarin is finding the right balance. While it's great at preventing clots, it also increases your risk of bleeding. Doctors regularly check a measure called your 'INR' to see how thin your blood is. A higher INR means your blood is thinner and takes longer to clot. This study is looking into whether we can aim for a slightly lower INR range (between 1.5 and 2.5) than usually recommended. Some early research suggests this might reduce bleeding without increasing the risk of clots or stroke, especially for people with a specific type of mechanical valve in the main body artery (aortic position).

The main goal of this research is to give doctors clearer guidance. If we can show that a lower INR target is safe and effective, it could significantly reduce the chances of serious bleeding for many people living with mechanical heart valves, making their long-term treatment safer and easier.

Key takeaways

This study explores a potentially safer warfarin dose for mechanical heart valves.
It aims to reduce bleeding risks without increasing blood clots or stroke.
It focuses on a specific type of mechanical valve in the main artery.
The study could provide clearer guidelines for doctors on warfarin management.
Participants' blood-thinning levels (INR) will be closely monitored.

Who may be eligible?

To take part in this study, you need to be at least 18 years old. You must have had a specific type of mechanical heart valve surgically placed in your main body artery (called the aortic position) at least three months ago. You also need to be able to understand and sign a consent form, or have someone who can legally make decisions for you sign it.

You won't be able to join if you have a second mechanical heart valve in any other part of your body. Also, if you are pregnant or think you might become pregnant during the study, you cannot take part. Finally, if your doctor is currently aiming for an INR level below 2.0, you wouldn't be eligible for this particular study.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Do you have one mechanical heart valve in your main body artery (aorta)?
Was your heart valve surgery at least 3 months ago?
Are you able to sign a consent form, or do you have someone who can sign for you?
Are you not pregnant and not planning to become pregnant during the study?

Answer every question to see your result.

What does participation involve?

The description provided does not include details about specific visits, assessments, medication changes, or follow-up duration for this study. Generally, in studies like this, participants would continue their usual warfarin treatment, but their INR (blood-thinning level) would be carefully managed within the study's target range. This would likely involve regular blood tests to check INR and consultations with study doctors. The overall duration of your involvement isn't specified, but clinical trials usually involve ongoing monitoring for a set period.

Potential risks and benefits

Taking part in a study like this means you might be among the first to benefit if a lower warfarin dose proves to be safer and reduces bleeding risks. However, there are also potential risks, as a lower dose could theoretically increase the chance of blood clots or stroke, though the study is designed to carefully monitor for this. You will be closely monitored by a medical team, and you always have the right to withdraw from the study at any time without giving a reason, and this will not affect your routine medical care.

Locations (35)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

Ziekenhuis Oost-Limburg
Verified postcode
Genk, Belgium· Recruiting
AZ Oostende
Verified postcode
Ostend, Belgium· Recruiting
Imelda Hospital
Verified postcode
Keerbergen, Belgium· Recruiting
Universitair Ziekenhuis Leuven
Verified postcode
Leuven, Belgium· Recruiting
University of Botswana, at Princess Marina Hospital
Verified postcode
Gaborone, Botswana· Recruiting
Sociedade Hospitalar Angelina Caron
Verified postcode
Campina Grande do Sul, Brazil· Recruiting
HEW Cardiologia LTDA
Verified postcode
Joinville, Brazil· Recruiting
InCor-HCFMUSP
Verified postcode
Cerqueira César, Brazil· Recruiting
Fundação Universitária de Cardiologia mantededora do Instituto de Cardiologia e Transplantes do Distrito Federal
Verified postcode
Brasília, Brazil· Recruiting
Dante Pazzanese Institute of Cardiology
Verified postcode
São Paulo, Brazil· Recruiting
St. Elizabeth Catholic General Hospital
Verified postcode
Kumbo, Cameroon· Recruiting
Nova Scotia Health Authority
Verified postcode
Halifax, Canada· Not yet recruiting

Common questions

What is an INR?

INR stands for International Normalized Ratio. It's a number that tells your doctor how thin your blood is and how long it takes to clot.

Why is warfarin important for mechanical heart valves?

Warfarin helps prevent dangerous blood clots from forming on your new mechanical heart valve, which could otherwise lead to problems like stroke.

What is the main goal of this study?

The study wants to see if using a slightly lower dose of warfarin can reduce serious bleeding risks without increasing the risk of blood clots or stroke.

Who is eligible for this study?

Adults (18+) with a single mechanical heart valve in their main artery (aorta) for at least 3 months, who are not pregnant.

Will my regular doctor still be involved?

Yes, your regular doctor will still be involved in your overall care. The study team will work with them regarding your warfarin management.

How to find out more

Emilie Belley-Côté, MD, MSc

emilie.belley-cote@phri.ca 905-527-4322 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.