A Plea to Parents and Family Physicians
The problem of misdiagnosis of Long QT Syndrome, often as a seizure disorder or epilepsy, has long been recognized and Electrophysiologists (EP's) have wrestled with how to solve the problem. Attached is a link to the abstract for Dr. Judith MacCormick's 2009 study of a cohort of 31 Long QT patients in New Zealand.
http://www.annemergmed.com/article/S0196-0644(09)00113-9/abstract
A parent reading this abstract might sum it up in one word, frightening. Four years on there has been marked improvement in the management of these patients but the misdiagnosis problem is far from being solved.
This past week I delivered an AED with training to a family in a town that is about a half hour drive from Toronto, Ontario, Canada, a part of the world where paediatric medicine is second to none. Their young teenager had just been diagnosed with Long QT type 2, and in addition to other therapies the patient's EP prescribed an AED for home and school. Multiple fainting/seizure episodes when the child was less than five years old had been misdiagnosed as a seizure disorder. Ten years on a near death event, triggered by physical activity, led to a proper diagnosis of Long QT Syndrome. Thankfully, the patient and the family cheated the odds for sudden cardiac death, but now they are faced with the challenge of ending a promising athletic career.
This close to (my) home story mirrors much of Dr. MacCormicks data from half a world away including a 10 year delay in diagnosis after an initial misdiagnosis of epilepsy. The greater concern of course is the significant number of preventable deaths in both the probands and their first degree relatives occurring during the long diagnostic delay, four in the NZ Study.
One of the common confounding factors is that fainting (syncope) associated with Long QT Syndrome and several other Inherited Heart Rhythm Disorders, often presents as seizure like activity. The likelihood that these types of events are neurological in origin is far greater than the likelihood that they are of a cardiac origin. However if a definitive neurological cause cannot be determined testing to rule out cardiac origin should be completed and interpreted by a physician that understands paediatric arrhythmia.
If you are the parent of a child, or know of a child or any person, that has ever been diagnosed with epilepsy or seizure disorder after experiencing one or more seizure/syncope episodes,
- especially if the diagnosis was one of "idiopathic" epilepsy
- or if the diagnosis was made without an ECG and other testing to rule out cardiac origin
- or if the ECG was not interpreted by a Paediatric Cardiologist or EP
- or if the physician seemed in anyway non-committal or unsure in their diagnosis
- or if other first degree relatives have experienced seizure/syncope episodes
- or if your "instincts" tell you that the diagnosis should be revisited
If you are a Family Physician that has a patient on your roster that meets any of the above criteria perhaps you would consider doing a new investigation of both the patient and other family members. Diagnosis and testing completed in the 20th century is particularly suspect and as the case noted above points out even a diagnosis from the 21st century can be incorrect and putting a patient at unnecessary risk of sudden death.
Whether you are family member or a Family Physician if you know of a person with a diagnosis of epilepsy or seizure disorder and it just doesn't seem to add up or sit well, consider circling back around to revisit possible cardiac origin. It may save a life, or two .....
