Sudden arrhythmic death syndrome (SADS) is the term used to describe the cause of death when someone dies suddenly and unexpectedly with no clear cause identified despite a full post-mortem examination.
SADS is believed to be caused by an abnormal heart rhythm (arrhythmia).
Symptoms
Sudden arrhythmic death syndrome (SADS)
Most people may not have any symptoms before a SADS event.
Symptoms of the heart conditions that cause SADS can include:
fainting when exercising or experiencing heightened emotion (for example, excitement or fear)
chest pain or unusual shortness of breath on exercising or exertion
palpitations that are fast and cause you to feel weak or to black out
The most important “symptom” of SADS is your family history. If you have a family member who passed away unexpectedly from a presumed heart cause under the age of 40 (and your doctors have recommended family heart check-ups), make sure you follow up on this and get checked.
Causes
Sudden arrhythmic death syndrome (SADS)
SADS can have multiple causes and some of these can be inherited heart conditions (conditions that run in families) that can cause arrhythmias.
With SADS, an arrhythmia stops the heart from pumping enough blood around the body suddenly and unexpectedly, starving the brain of oxygen and causing cardiac arrest . In some cases, cardiac arrest can be treated with CPR and treatment with an automated external defibrillator (AED). Sadly, this is not always available to the person and is not always successful.
The condition which caused SADS may be undetectable after death, but sometimes a specialist heart clinic will be able to perform extra testing, such as genetic testing, to find out more information for your family.
The specialist clinic may also recommend heart check-ups for first-degree relatives (parents, siblings and children) of the person who passed away, to look for any evidence of an inherited cardiac condition in the family.
Prevention
Sudden arrhythmic death syndrome (SADS)
Know your family history and, if you have a family history of SADS, visit your doctor and speak to them about your concerns.
If you have an inherited condition that may cause arrhythmias, it is important to follow the advice of your doctor or specialist.
It is also helpful to take care of your heart by living a heart-healthy lifestyle.
If you have a loved one who is at risk of arrhythmias because they have an inherited heart condition, learning CPR and how to use an AED can allow you to respond quickly if they need help.
Community First Responders are trained volunteers who can provide CPR and AED use during emergencies, while waiting for an ambulance to arrive. Managed by the National Ambulance Service, their website has information on CPR training and CFR groups in your area. See becomeacfr.ie.
Diagnosis
Sudden arrhythmic death syndrome (SADS)
If you have experienced a confirmed SADS death in your family, your doctor is likely to recommend testing.
Tests may include:
Electrocardiogram (ECG) – This is a painless test that measures the rhythm and electrical activity of your heart.
Echocardiogram – This test uses soundwaves (ultrasound) to take a moving picture of your heart. It allows your doctor to see how your heart is working.
Holter monitor test – This test involves wearing a special monitor that records and monitors your heart rate over a long period of time (usually 24 to 48 hours).
Stress test – Your doctor will monitor your heart as you exercise on a treadmill or an exercise bike to see how well it’s working during physical activity.
Genetic testing – If there has been a sudden death in your family that is believed to be SADS, your doctor will recommend that the closest family members to the SADS victim see a cardiologist in a specialist clinic. The specialist will be able to advise if genetic testing is possible or needed.
Other specialty tests – Your doctor may advise further tests such as an MRI, CT scan or coronary angiogram.
Treatment
Sudden arrhythmic death syndrome (SADS)
Not all families who have experienced the death of a loved one due to SADS will have an inherited heart condition.
In Ireland, statistics show that up to a third of these families have an inherited cardiac condition. For the families that do have an inherited heart condition, treatment will be focused on that diagnosis. Common treatments include:
lifestyle changes
avoiding medications or situations that may trigger heart-related symptoms
medication (for example, beta blockers)
implantable cardioverter defibrillator (ICD) or loop recorder placement
other surgical interventions that your doctor will discuss with you
You can take care of yourself by ensuring that you attend your doctor for regular check-ups and take any medication as prescribed. If you start to experience any symptoms of SADS, call 999 or 112 immediately.
Support for you
Sudden arrhythmic death syndrome (SADS)
Losing a loved one to SADS or living with a SADS-related heart condition is traumatic and overwhelming.
We are here to help with professional counselling and emotional support programmes, our Nurse Support Line, information events and our online community.
You can contact the Irish Heart Foundation Nurse Support Line on 01 668 5001 or visit irishheart.ie/support-for-you to view our full range of supports.
Long QT syndrome (LQTS) is an inherited condition and one of the most common causes of arrhythmia that can lead to SADS if left untreated. Here are some resources if you (or a loved one) are living with LQTS:
Our booklet Step by Step through heart medicines contains information about the different medicines used by people with heart conditions. Download it here.
Our booklet Step by Step through cardiomyopathy is for people living with cardiomyopathy, their families and their loved ones. It contains information about cardiomyopathy and how it might affect your everyday life. Download it here.
CRY Ireland provides peer support, counselling and family events for people bereaved by SADS.
The LQTS Facebook group is moderated by a group of people living with the condition.
First Light offer support to families who have experienced the sudden, unexpected death of a child.
Anam Cara offers information and peer support to bereaved parents of children.
