Dr Arvind Chandratheva gives SR Times his expert knowledge on the challenges of managing cryptogenic stroke, and the value of technological innovations in improving stroke patient outcomes.
What is a cryptogenic stroke and why is it a problem?
Stroke is one of the leading causes of death and disability in the UK, and the overall costs attributed to stroke are a staggering £25.6 billion per year. In 75 percent of stroke cases, consultants can identify the origin of the condition. However, in 25 to 40 percent of cases, despite blood tests and further investigations, the source remains unknown. These strokes, without a clear cause are labelled as cryptogenic strokes. 25 percent of cryptogenic strokes are the result of atrial fibrillation (AF) which refers to an irregular, and often very fast heart rate. Those with AF are five to seven times more likely to form blood clots and suffer a stroke.
Typically, AF is asymptomatic, although patients that are symptomatic tend to notice an irregular heartbeat. There is some societal understanding around the initial signs of stroke including, facial paralysis and slurred speech; but there are many other crucial indicators, as well as type of stroke, that need to be more widely recognised.
What does the patient journey look like, post stroke?
The stroke patient journey can be a whirlwind, with many patients suffering life changing consequences. Once out of the acute treatment phase, patients are then released back into the community. This moment can represent the start of their experience living with stroke.
Throughout an individual’s stroke journey, it is their community that remains the most variable factor, for example, geographical location can impact their access to appropriate care. Often the severity of patients’ functioning post stroke is varied, some suffer with cognitive abnormalities, anxiety, or disability, while others have very few symptoms.
Once in the community, patients receive a follow up appointment with a doctor and may receive a follow up with the community therapy team. This provides limited medical interaction with the patient. Multidisciplinary support can be extremely valuable, although it presents a huge resourcing challenge across the NHS. This is because there is an intense need for stroke patient support for as long as it may be required, which in some instances can be lengthy and as a result, costly.
How can insertable cardiac monitors (ICMs) provide support to stroke patients in the community?
Cryptogenic stroke patients often have lots of unanswered questions which can be anxiety provoking. The uncertainty surrounding the stroke’s origin creates fear that it could occur again. This is understandable, as one in four stroke survivors will experience a secondary stroke within five years, which is often more severe and disabling than the first.
For the majority of stroke survivors, there is a lot of emphasis on the importance of returning to “normal”. Medtronic’s LINQ insertable cardiac monitor (ICM), a diagnostic device, operates 24 hours a day for a duration of three to four and a half years, recording heart rate and rhythm, unlike other short-term monitoring technologies. The ability of the ICM to work continuously enables stroke patients to find some solace in knowing that they are being monitored, and that there will be further investigation into the factors contributing to their cryptogenic stroke.
Can you tell us about the pilot scheme taking place at UCLH that aims to streamline the cryptogenic stroke pathway?
At UCLH, the current care pathway completes an initial period of cardiac monitoring to determine the nature of a patient’s stroke. Once consultants have identified whether the stroke is of a cryptogenic or embolic stroke of an undetermined source (ESUS), the patient is allocated the appropriate care pathway. If the stroke is of a cryptogenic nature, the patient is opted into the UCLH pilot scheme, whereby they are added to a newly developed online referral system, which enables consultants to refer patients quickly onto the ICM pathway.
Once referred, a clinical assessment is carried out by the stroke nurse practitioners, and the ICM device is implanted. The focus remains on “door to detection” and whether it is completed in a timely and efficient way.
UCLH’s pilot was initially intentionally over-supportive, to ensure robust governance in its infancy, but there is scope to streamline as it matures, and we can learn from patient experiences. It is exciting to see the growth adoption of incredible innovations such as ICMs, with UCLH’s pilot also demonstrating that stroke nurse practitioners are integral to the pathways success whilst being the best source of patient comfort and symptom recognition.
What are the existing ICM guidelines, and is there a need to standardise this process?
Currently, in addition to NICE guidance, the European Stroke Organisation (ESO) guidelines has recommended the use of ICMs to maximise AF detection in cryptogenic stroke and transient ischaemic attack (TIA) patients. Although, further developments are needed to incorporate and facilitate immediate monitoring after patients have left the acute stroke unit. Prolonged cardiac monitoring (PCM) has demonstrated benefits in reducing the risk of recurrent stroke and increasing the incidence of AF detection, as compared to conventional monitoring. The next key challenge is ensuring that information is reported properly so that referrals can be made efficiently.
In some Nordic countries, implantable cardiac monitoring for cryptogenic stroke patients is an inpatient procedure, completed within a maximum of 10 days post stroke admission. In the UK, this is an outpatient procedure. Often, there are long waiting lists for outpatient procedures and stroke patients may need to wait several months for their ICM device to be fitted. Thus, there is a need to standardise longer term monitoring and early treatment amongst cryptogenic stroke patients.
However, one must recognise that it is hard to standardise treatment, due to the nature of variables including, timing and remote or underfunded geographical locations, limiting the accessibility of vital resources. The Sentinel Stroke National Audit Programme (SSNAP) aims to improve the collection of data, recording the six-month outcome for stroke patients to better inform care pathways, and to improve patient outcomes.
What excites you the most about the future of stroke treatment pathways?
The most rewarding aspect of operating within the stroke care pathway is working with my team. I enjoy specialising in an area where I can have a positive impact on the lives of patients. There is also great fulfilment of being a part of the entire patient journey, rather than just when the patient is unwell in the acute hospital ward. There is a big impact to be made post cardiac monitoring, and it is exciting to be a small part of improving this pathway.
