The Role of the Death Investigator in Preventing Sudden Cardiac Death

When a child dies of a cardiac cause seize the opportunity to protect siblings and cousins

In some jurisdictions they are called Coroners in others Medical Examiners. Regardless of job title they have the potential to significantly reduce the toll – 7,700 per year - that Inherited Heart Rhythm Disorders take on young people in provinces and states across Canada and the US.

The Coroner’s responsibility begins with correctly identifying the cause of death.  For the first degree relatives of a child that died of sudden cardiac arrest caused by an underlying genetic heart rhythm disease the words “unknown” or “undetermined” or “possible cardiac” on the death certificate is too often their own death sentence. (this will sound like hyperbole …. until it happens to your family). Inherited structural diseases, the cardiomyopathies such as HCM and ARVC can normally be detected through routine examine due to the extensive remodelling of the hearts structure. Inherited electrical diseases such as Long QT and Brugada Syndromes are more challenging as the telltale electrical signature of the disease is now switched off.  Often molecular genetic testing is required to determine cause. There are currently at least 15 genes and many more mutations associated with the various heart rhythm diseases and with the intensity of research in the field that number grows almost monthly. When on autopsy a clear phenotypical cause of death does not present the coroner must use DNA testing to seek a genotype that suggests a likely cause.

Coroners and ME’s should be collecting and storing genetic material, blood and tissue, for all young person deaths - under the age of 35 would be ideal, 18 is too low. Every province and state should have a DNA Bank where death investigators can safely store and easily access genetic material. Collecting and testing DNA samples from infants where the death was classified as SIDS (Sudden Infant Death Syndrome) is essential. Published research estimates up to 30% of all SIDS death are caused by an arrhythmia gene.

Every time a young person dies of “cardiac” or “presumed cardiac cause” both sides, the ME's Office and the Family (with guidance from the family physician) should be pursuing DNA testing.  Typically if the family does not ask, the ME will not initiate genetic testing.  Typically if healthcare professionals do not present DNA testing as an option the family is unaware of its availability and unaware of its lifesaving potential for gene positive first degree relatives. This is why death investigators and family physicians should be simultaneously informing parents of their options.  If it takes two or three or ten years for the family to recognize the importance of genetic testing the genetic material should be readily available when the call comes.  Note:  The family physician may wish to call upon the services of a genetic counsellor to help the family understand the importance and significance of genetic testing and the implications of all of the possible results – positive, negative, undetermined or any number of shades of grey.

When the testing is complete and the results are positive for a known genetic association with a heart rhythm disease the real work begins, notification and testing of all first degree relatives.  Most primary heart rhythm disease are transmitted by an autosomal dominant gene – if one parent carries the gene on average half of the children will acquire the gene, with no gender bias.  Step one therefore is determine which parent carries the gene.  Note: I have worked with a family where one parent was positive for Long QT and the other for ARVC, rare but possible.  Step two is to test siblings and then aunts, uncles, cousins and grandparents on the affected side of the family. It is common to identify four, five or more affected first degree relatives for every index patient.  This is the silver lining; this is the gift that the deceased has given to his or her family.  From one child’s death comes the ability to identify many at-risk relatives and provide them with the appropriate prophylaxis for sudden death.  
 

Step two is not without challenges. Identifying and locating all of the potentially affected family members may be difficult, convincing each of them that they should get tested for a genetic disease that they have never heard of  may be near impossible.    “Catcallamungowhatapolywhatacardia….. You think I might have this wack-a-doodle disease and should get tested?”    At this point all of the stakeholders – the Parents of the deceased, the Family Physician, the Paediatric Cardiologist/Electrophysiologist, the Genetic Counsellor, the Coroner’s Office must work together to protect the living.

Often this process moves into areas where the moral/ethical issues around personal health information privacy come into play.  Navigating these waters can be tricky, rules must be followed and boundaries respected. On a very personal note I believe that when a child’s life hangs in the balance it is best to err on the side of protecting the child.  I hate it when children die with their parents privacy still intact.

The other critical challenge in this process is speed. The Family and the Coroner’s Office must move quickly to pinpoint the cause of death and then to locate and test the first degree relatives. It is difficult to say exactly what the appropriate time frame is for this often complex process to play out but I would submit that if seventeen and eighteen year old cousins die just over one year apart the system has failed both families. Anecdotally, I hear some version of this story far too often.

In every jurisdiction in North America there is significant room for improvement in the way death investigations of young people dying from cardiac causes are handled and followed-up.  If you are an advocate for cardiac arrest prevention in youth please be sure to include improving protocols for death investigations on your must-do list when speaking with provincial or state bureaucrats and legislators.  If you are a family that has lost a child to sudden cardiac death and are unclear what triggered the event push the healthcare and death investigation systems for answers.