Global study targets rare heart condition in women

Published: 28 September 2025

A global trial, led in part by New Zealand researchers, will test safer treatments for SCAD – a rare heart condition affecting women – offering hope for clearer guidelines and better outcomes worldwide.

A groundbreaking international clinical trial, with significant New Zealand involvement, is set to transform treatment for spontaneous coronary artery dissection (SCAD), an under-recognised but serious cause of heart attacks in women and mothers. 

SCAD occurs when a tear forms in the wall of an artery, reducing blood flow through the artery, sometimes causing a blockage that can lead to a heart attack. 

It is responsible for up to a third of heart attacks in women under 50 and nearly half of those during pregnancy. Despite growing awareness, there is no global consensus on how to best treat SCAD due to a lack of robust clinical evidence. 

“It’s difficult for researchers to study the best treatments for this type of heart attack,” Caroline Alsweiler, recipient of a 2025 Heart Foundation project grant and a senior clinical research scientist from the Green Lane Coordinating Centre says. 

SCAD often strikes young, otherwise healthy women, a group not typically considered at risk for heart attacks. 

“When a young, otherwise healthy woman arrives at an emergency department with chest pain, a heart attack is often the last thing doctors consider. Because of her age and lack of typical risk factors, it’s not usually the first diagnosis they investigate.  

“As a result, SCAD is frequently missed.”

First ever global SCAD trial

Now, a global team of researchers, including New Zealand cardiologists and patients, are launching the first randomised clinical trial to determine the safest and most effective treatment for SCAD. 

The New Zealand part of the trial will be managed by Caroline’s team at the Green Lane Coordinating Centre who aim to enrol around 50 New Zealand patients out of 3,250 patients worldwide.

The trial will compare two widely used treatment strategies: dual antiplatelet therapy (DAPT) which typically uses aspirin plus another blood-thinning drug, and single antiplatelet therapy (SAPT) which uses aspirin alone. 

While both are standard treatments for traditional heart attacks, it’s unclear which is safer or more effective for SCAD. 

“The challenge with knowing which antiplatelet drug to use in these patients is because these drugs make your blood slippery, which means that you bleed more easily while taking them.

“Instead of a clot blocking the artery like in other heart attacks, SCAD involves blood entering the artery wall and bulging inward, which can worsen with blood thinners.” 

Why the study matters

Currently, clinicians treating SCAD are left to make educated guesses about which of the antiplatelet drugs to use, at what dose, and for how long.  

“When it comes to SCAD, clinicians are often left guessing and hope for the best, because there’s no solid evidence provided to guide their clinical decisions in this patient population.

“For a typical heart attack, the standard might be clopidogrel for 12 months, but with SCAD, we just don’t know. This research is about changing that and providing the data clinicians need to make informed decisions.” 

Potential impact

Since the medications being tested are already widely available, the trial’s findings could be rapidly adopted into international treatment guidelines, without the delays associated with new drug approvals. 

That means cardiologists in New Zealand and around the world will be able to rapidly adopt evidence-based treatment protocols that are safer and more effective for SCAD patients. 

The potential benefits for patients could be significant, leading to fewer adverse events like recurrent heart attacks or bleeding complications, shorter hospital stays, faster recovery, reduced medication and improved quality of life. 

Heart Foundation Medical Director Dr Gerry Devlin says the trial will have a significant impact for thousands of people globally.

“SCAD is a condition we still don’t fully understand, and there’s very little guidance for clinicians on how to treat it safely.  

“The results of this research will provide the clarity we’ve been waiting for with respect to antiplatelet therapy and will inform international best practice treatment guidelines meaning thousands of women around the world will benefit from safer, more effective care.”