AuthorisedTherapeutic confirmatory (Phase III)Interventional

MAMI Use of the Methoxyflurane as pain-killer in the prehospital management of Acute Myocardial Infarction

Imagine someone is having a heart attack and needs pain relief right away before they get to the hospital. This study is called MAMI and it's comparing two types of pain medication: Penthrox, which is a liquid you breathe in, and morphine, which is commonly given for severe pain. The main goal is to find out if one of these medicines reduces a person's chest pain more effectively within 30 minutes. Researchers will also be looking at how quickly pain relief happens, how the medicines affect heart rate and blood pressure, and if there are any side effects like dizziness, sickness, or difficulty breathing. The study is for adults of any age, both men and women, who are experiencing a heart attack.

At a glance

Status

Authorised

Phase

Therapeutic confirmatory (Phase III)

Sponsor

Assistance Publique Hopitaux De Paris

Enrolment target

700

Start

02 Feb 2026

Acute Myocardial Infarction

What is this study about?

When someone has a heart attack, the chest pain can be very severe and frightening. Getting effective pain relief quickly, even before they arrive at the hospital, is really important. This study, called MAMI, is a crucial step in understanding the best way to manage this pain in the very first moments. It's designed to compare two common pain relief options: Penthrox, which is a medicine breathed in, and morphine, which is a well-known strong painkiller.

The main thing researchers want to find out is how many people get significant pain relief within 30 minutes of getting the medicine. They'll be using a simple scale where patients rate their pain. But it's not just about how quickly the pain reduces; the study will also look at how these medicines affect important body functions like heart rate and blood pressure, and if they cause any unwanted side effects such as feeling dizzy, sick, or drowsy.

By carefully comparing these two treatments, doctors hope to learn which one is safer and more effective for providing fast pain relief to people having a heart attack. This knowledge can help emergency services make better decisions about how to best care for patients before they even reach the hospital, potentially improving outcomes and making a very difficult experience more bearable.

Key takeaways

This study compares two pain medications for heart attack patients.
It aims to find out which medicine reduces pain faster and better in the emergency stage.
Penthrox (breathed in) and Morphine (injected) are being tested.
Researchers will also check for side effects like dizziness or changes in breathing.
The findings could improve early treatment for heart attack pain.

Who may be eligible?

This study is looking for adult patients who are currently experiencing a heart attack. To take part, you would need to be at least 18 years old – there's no upper age limit.

Both men and women are welcome to participate in this research. The most important thing is that you are having symptoms of an acute (sudden) heart attack and meet the other medical criteria for the study.

This study specifically focuses on immediate pain relief for this serious condition, so it's not for people with other types of pain.

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.

Am I at least 18 years old?
Am I currently experiencing symptoms of a heart attack?
Am I being seen by emergency medical services for a heart attack?
Am I able to communicate my pain level to the medical team?

Answer every question to see your result.

What does participation involve?

If you are eligible and agree to take part, the medical team will give you either Penthrox or morphine. The study is designed so that neither you nor the medical team will know which treatment you are receiving until after your pain has been assessed, which is normal for this kind of research. You will be asked about your pain levels using a simple score at different times, especially within the first 30 minutes. Medical staff will also monitor your vital signs like heart rate and blood pressure closely, and check for any side effects. All of these checks will happen during your initial care and hospital admission, without needing extra visits just for the study. The total duration of your participation in the study itself is focused on the initial hours of your heart attack treatment.

Potential risks and benefits

Taking part in this study means you would receive one of two standard pain relief treatments for a heart attack. The potential benefit is that your pain might be reduced quickly and effectively by one of the study medications. As with any medication, there can be potential risks or side effects, such as dizziness, feeling sick, or your breathing or heart rate being affected. The medical team will be closely monitoring you for these. You always have the right to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

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

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Unverified
France

Common questions

What is a 'heart attack' in simple terms?

A heart attack happens when blood flow to part of the heart is suddenly blocked, often by a blood clot. This can damage the heart muscle and cause chest pain.

What is Penthrox?

Penthrox is a liquid painkiller that you breathe in through a special device. It's sometimes called 'the green whistle' and is used for quick pain relief.

What is morphine?

Morphine is a strong pain-relieving medication that is often given by injection for severe pain, like that experienced during a heart attack.

Will I know which treatment I'm getting?

No, this is a 'blinded' study, meaning neither you nor the medical team will know if you're getting Penthrox or morphine until after important measurements are taken. This helps ensure fair results.

Why is this study important?

It's important because it could help doctors understand the best and quickest way to relieve severe chest pain for people having a heart attack before they even reach the hospital, potentially improving their care.