For health professionals

SCAD patients present similarly to other types of MI, most commonly with chest pain and other signs and symptoms of myocardial ischemia. It’s important to distinguish the pathophysiology of SCAD from an MI due to atherosclerosis, since acute and long term management differs.

Who Experiences SCAD?

SCAD is the #1 cause of heart attacks among women under the age of 50 years and those who are pregnant or have just given birth. Most people with SCAD are young, healthy, active women who have no family history of heart disease or personal risk factors for atherosclerosis. The average age is 42 to 52 years but it has been described in teenagers and women in their 7th decade of life. Although less common, SCAD can affect men too. Some SCAD patients have been found to have an underlying blood vessel disorder most commonly fibromuscular dysplasia (FMD).

What we know about SCAD:

  • Non-atherosclerotic (that is not due to plaque) coronary heart disease
  • Affects healthy individuals with few, if any risk factors
  • Conservative non-invasive treatment is often best
  • Arteries frequently heal without intervention
  • As awareness and diagnosis have increased, the medical community is realising that SCAD is not so rare

How is SCAD Diagnosed?

SCAD patients typically have electrocardiogram (ECG) findings and troponin level elevations consistent with heart muscle cell loss. A diagnosis of SCAD as the specific type of MI is by its typical appearance at the time of a coronary angiogram or, occasionally, by CT coronary angiography. In the case of sudden unexpected death, an autopsy may reveal SCAD. Most people (95%) treated in hospital do very well. However chest pain and recurrent SCAD can recur (up to 30% of cases over a 10 year timeframe).

How is SCAD Treated?

Although much has been learned about SCAD in the past few years, the cause of SCAD remains obscure and no primary preventive treatment has been identified. After an episode of SCAD, strict blood pressure control and a beta-blocker drug may reduce the chance of a recurrence. Accurate differentiation of SCAD from other causes of MI is crucial because the approach to acute and long term care is different. Specifically, patients undergoing percutaneous coronary intervention (PCI) for MI due to SCAD have technical success rates that are markedly reduced compared to PCI success rates for atherosclerotic MI (62% vs 92%). Also research has noted a substantial rate of spontaneous vascular healing without intervention and suggests a role for conservative management in stable SCAD patients who have preserved coronary flow. Conservative management usually includes 4-5 days of careful inpatient monitoring. Statins do not appear to prevent another SCAD heart attack and one study found more recurrences in those taking statins. SCAD can recur, so vigilance, evaluation for associated conditions, and staying up-to-date on emerging research is also important.

Mayo Clinic SCAD Study Findings

The goal of the Mayo Clinic SCAD Research Program is to advance the understanding of the underlying causes and risk factors for this poorly understood condition and develop solutions for optimal diagnosis, treatment and prevention.

Since its inception in 2010, the SCAD Research Program has gained new insights into associated conditions and treatment approaches. Highlights and significance of findings from the Mayo Clinic SCAD Research Program include:

  • Extracoronary vascular abnormalities. A high rate of abnormalities in noncoronary blood vessels has been identified in patients with SCAD. These include fibromuscular dysplasia (FMD)aneurysms and additional dissections. Patients with these findings may need additional imaging and follow-up and may be at higher risk of recurrent SCAD.
  • Specialized imaging techniques. Mayo researchers are defining the role and value of specialized imaging of the inside of the coronary artery at the time of SCAD to make an accurate diagnosis and guide treatment. The SCAD diagnosis can be missed if only standard coronary angiography is used.

The Mayo Clinic SCAD Research Program has demonstrated that advanced imaging techniques such as intravascular ultrasound and optical coherence tomography can not only enhance diagnostic accuracy, but also guide treatment in the crucial early minutes of a heart attack.

  • Complications with stenting. The program team has reported significantly lower success rates and higher complication rates when coronary artery stenting or ballooning is utilized to open artery blockages due to SCAD, compared with rates for patients with typical heart attacks. This has implications for early decision-making for treatment and highlights the need for an accurate diagnosis.
  • Selective intervention. Mayo researchers have observed a significant rate of spontaneous healing of SCAD-affected arteries that occurs without specific intervention (medical treatment only). This has led to a change in Mayo’s clinical practice, whereby in select patients with SCAD, clinicians do not intervene with stenting or bypass surgery, but instead allow them time to heal on their own.
  • Routine statin use not recommended. Unlike atherosclerotic disease, there is no evidence that statins prevent recurrent myocardial infarction or dissection. Since there is no evidence of benefit, statins should not be routinely given to patients with SCAD, but reserved for those with hyperlipidemia.
  • SCAD incidence is not as rare as previously believed and may be the major cause of heart attack in women under age 40 and in pregnant or postpartum women.
  • Male participants needed. There is an inherent selection bias in the program’s sample due to the origin of the research from a women’s online community. Further, the research team has observed sex differences in the cause and outcomes of SCAD. Therefore, a focus on recruiting more men to the program registries is critically important to better understand the significance of these findings and the true prevalence of SCAD in men and women in order to provide optimal care.
  • More information is available. Mayo Clinic SCAD researchers participated in the development of the 2018 scientific statement from the American Heart Association on SCAD, which provides a comprehensive overview of the condition. View the AHA statement on PubMed

Treating SCAD Survivors

Additional Notes on Treatment:

  • For SCAD survivors who suffer from migraines, which are commonly associated with SCAD, the use of triptans as drugs to treat migraine should be avoided.
  • Since it is believed that there is a hormonal link to SCAD, survivors may be directed to take a non-hormonal form of birth control and avoid taking any hormone therapies.
  • Survivors will likely feel more fatigued or tired for some time after your SCAD with some people taking up to 3-6 months or more to find their new normal.
  • Some SCAD survivors experience mild unexplained chest pain following their heart attack
  • Experiencing a SCAD heart attack can be an extremely unexpected and frightening event. Seeing that this condition often affects people who have very few or no risk factors for heart disease it can be traumatic for the sufferer and their families and counselling may be recommended.

Cardiac Rehabilitation

The Mayo Clinic Team
The Graham lab

Cardiac rehabilitation is definitely recommended after surviving a SCAD heart attack. Each case of SCAD will be different, however it is generally recommended that SCAD survivors avoid lifting items that require you to strain or bear down. This varies depending on fitness and a person’s build.  Don’t overdo it with exercise – especially avoid isometric exercise, such as weight lifting – but also continue doing what you like, especially if it reduces stress.

More guidelines for cardiac rehab

Victor Chang Cardiac Research Institute

Executive Director of the Victor Chang Cardiac Research Institute, Professor Bob Graham, is leading this Australian first research program which now has hundreds of Australian SCAD survivors, including some families with more than one affected member participating. The Institute’s researchers are looking to identify genetic variations that contribute to the development of this disease

“The underlying defect causing SCAD is entirely unknown, however, our work and that of others suggests that it is most likely due to a gene change that enhances susceptibility to vessel rupture. Our purpose is to better understand, treat and prevent SCAD by identifying factors that predispose the coronary artery to spontaneous tearing.

Our objectives are to investigate the genetics and cell biology, as well as blood pressure and heart function responses, of our familial SCAD survivors versus controls. Our research would bring together multi-disciplinary, internationally-competitive researchers to dissect the molecular mechanisms underlying SCAD, with the objective of identifying targets for the development of effective preventative and treatment strategies, irrespective of ethnicity.”

All SCAD Survivors are encouraged to join this research program, and can register or found out more by emailing scad@victorchang.edu.au.

Join the Mayo Clinic SCAD Research Program:

Mayo Clinic’s Spontaneous Coronary Artery Dissection (SCAD) Research Program is part of an innovative multidisciplinary collaborative research and clinical practice initiative formed in 2010. The goal of the program is to advance the understanding of the underlying causes and risk factors for SCAD and develop solutions for optimal diagnosis, treatment and prevention.

The international Mayo Clinic SCAD Research Program was created in response to data collection and a research agenda initiated by SCAD survivors via social networking. The study population is the largest known SCAD registry in the world.

Register to join many Australian SCAD survivors in this SCAD Study at Mayo Clinic by emailing mayoscad@mayo.edu

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