Articles

Thrombectomy

2
27/11/2017

The future of stroke treatment

For too long has the treatment of stroke only consisted in the rehabilitation and prevention. The event in its acute damaging phase was not treatable. After the successful introduction of clot-busting therapies, where thrombus-dissolving agents are administered intravenously, we have now a mechanical option called thrombectomy available, an intra-arterial clot removing approach.

 

medical thrombectomy

How does thrombectomy work?

Just like a coronary intervention, cerebral thrombectomy uses intra-arterial catheters to access the area where the blockage occurs. And just like a coronary angiography, the procedure is performed by an interventional cardiologist – perhaps in the future renamed to neuro-cardiologist.

The aim is to quickly Identify the area where the obstruction occurs. This is done with an urgent CT-scan on arrival to the emergency department. In order to be eligible for thrombectomy, the blocked vessel in question must fulfil specific criteria relating to its size and location. Only large vessel occlusion and currently just arteries of the anterior cerebral circulation are amenable to thrombectomy. The time frame in which the clot is to be removed is 6 hours, keeping in mind that faster action delivers better results – time is brain.
The catheter is then inserted via the femoral artery and

What are the dangers?

Complications of endovascular procedures can be related to vessel injury caused by the device like perforation, dissection bleeding, vascular access or radiological contrast media.

What is the future holding?

Rapid, safe and effective arterial recanalisation to restore blood flow to minimise brain damage remains the primary goal when managing acute stroke management. Recent positive randomised clinical trials show that endovascular thrombectomy for large vessel ischaemic stroke substantially improved the outcome and reduced disability. To become available for every future stroke patient, this new technology will demand interdisciplinary co-operation, and no doubt require organisational changes within the care provider as well as public awareness and infrastructure.

A clear and simple demonstration of this procedure can be seen at:

Videoanimation

Your resting heart rate (RHR) – a fitness indicator

26/10/2017

What does your resting heart rate (RHR) tell you?

The resting heart rate gives you a pretty good clue on how ‘fit’ you are. There is a direct link between a high RHR and increased risk of dying from cardiovascular events according to some research.

A study from 2015 found that a higher resting heart rate is associated with a higher risk of dying from a cardiovascular disease, even in people who do not present with the usual risk factors.

It was found that when comparing with a resting heart rate of 45 beats per minute (bpm), the rate for All-cause mortality risk increased linearly as resting heart rate went up. The most significant increase in mortality risk was however at a resting rate of 90 bpm or more.

Further analysis showed a mortality excess of 30-50% for every increase of 20 beats per minute at rest.

What is a reasonable resting heart rate?

A regular heart rate for adults ranges from 60 to 100 bpm at rest.

In general, a slower beating heart at rest is a sign of a more efficient heart function and a fitter cardiovascular condition. A marathon runner, for example, could have a heart rate as low as 40 beats a minute.

If your heart rate is continuously above 100 bpm, consult your doctor. He/she might want to do some tests to find the underlying cause.

How do I measure my resting heart rate?

Do it first thing in the morning, ideally before getting up. Find the pulse on the thumb-side of your wrist, and count how many times it beats within 60 seconds, this gives you the beats per minute figure. You can also check it by counting the pulse in your neck.

Several factors can influence heart rate:
  • Activity levels
  • Air temperature
  • Standing up /Lying down
  • Emotions
  • Body size/volume
  • Medication

How can I improve my resting heart rate?

First of all, start with regular aerobic exercise programs such as cycling, running, walking, swimming or hiking.

It has also been found that a good night sleep can help improve your heart rate. The healthy cardiovascular friendly diet can also contribute to a healthier heartbeat. Try and reduce stress, both physical and emotional and if you suffer from anxiety, try some relaxation therapies. Smoking as well as being overweight also increased your resting heart rate – you know what to do.

Why do we get cold sores?

25/10/2017

Where do cold sores come from?

Although cold sores appear with your cold, they are not caused by the cold virus but an entirely different one, called Herpes Simplex Virus (HSV); to be more precise HSV-1. Many of us carry this virus, sometimes without even knowing and women are slightly more prone to this infection. Over 50 % of the population in the Western World are infected with HSV-1, in some regions of Europe even up to 80%.

Once infected, this virus is likely to stay with you the entire life. It tends to sleep in the nucleus of sensory nerve cells without causing any harm, now and then it may, however, wake up and trigger the typical blisters on the skin from where this nerve conducts sensation. This skin rash typically affects the lips and skin around mouth and nose. It is not entirely known what causes the virus to become active; fever can be a trigger hence the association to the cold and the name “fever blisters”; ultraviolet light is another cause, and both physical and emotional stress may also cause a reactivation. These blisters often start with a tingling and then become painful, they will crust over and heal without leaving a scar. They can last up to 10 days.

How did I get it in the first place?

Infection happens when you get in contact with the virus, and it can enter via breaks in your skin or mucosa. An intact skin does not let the virus though and acts as a perfect barrier. The virus itself can be found in saliva, the affected skin and even tears. Note that it is mostly transmitted from people with an activated HSV, but it can also be given to you by people who do not have any symptoms.
It is recommended that people who are experiencing a cold sore should ensure that their affected skin from touching other people or objects that could act as a mode of transfer and to refrain from exchanging saliva.

What about HSV-2

When we hear Herpes, we associated this word mostly with a sexually transmitted disease. Here HSV-2 comes into play. With the same mode of action like his upper body fellow, this virus affects the skin of the genital areas and is transmitted during sexual intercourse. Traditionally 80% of genital herpes is caused by HSV-2 and 20% by HSV-1. The incidence of HSV-1 infection in the genital area has recently increased. Especially in adolescents, this ratio has moved up to 30-40%, which is explained by increased oro-genital contact.

How to treat sold sores

Cream which contains the antiviral Acyclovir, especially if applied early in the development of cold sores, can help to reduce the duration. In other words, the pain period will be shorter, and the crusting over and healing process will happen faster. Other than that, lip balm against dry lips which often go hand in hand can give some relief.

HIV Preexposure Prophylaxis (PrEP)

22/10/2017

Antiretroviral Medication as Prophylaxis

 

Preexposure Prophylaxis (PrEP) with antiretroviral drugs is a concept that is gaining increased recognition as a method of primary prevention for people with a risk of becoming infected with the Human Immunodeficiency Virus. We know what works best in the prevention of HIV but human nature, mainly when guided by their sexual drive, will not always follow the best advice – a fact that even the Catholic church must have realised by now.

Prophylaxis PreP

Recent clinical trials show promising results for the use of PrEP when delivered as part of a comprehensive set of prevention services for individuals at high risk for HIV acquisition. This approach works best when accompanied by regular monitoring of HIV status, side effects, adherence and risk behaviours.

It is biologically plausible that antiviral medication could affect the acquisition of HIV especially when the prophylactic drug has a long half-life, achieves a high concentration in monocytes, macrophages and genital secretions, has a high barrier to genetic resistance and is safe and inexpensive.

Tenofovir seems to tick all these boxes and is the most widely studied substance either in combination with Emtricitabine (Truvada) or on its own.
The danger of PrEP facilitating resistance and thus spreading a drug-resistant virus is a possibility, especially if this method becomes widespread.
A possibility exists that offering PrEP could encourage increased high-risk sexual activity. However, no evidence of increased high-risk sexual activity was demonstrated in the few observational studies that addressed this.
High-risk individuals include those who have a partner known to be HIV infected or who are sexually active within a high prevalence area. In the gay community, the use of PrEP is becoming a regular feature especially in men participating in anal intercourse.

Aspirin in colorectal cancer

21/10/2017

The timeline of Acetylsalicylic Acid

Aspirin (Acetylsalicylic Acid), who started its life as an ordinary headache tablet turned out to be an effective blood thinner and established itself on the cardiology shelves of our pharmacies. If the outcome of recent studies is to be confirmed, Acetylsalicylic Acid will soon be prescribed by oncologists.

Encouraging outcomes

Evidence is accumulating that Aspirin has a beneficial effect in the prevention of colorectal cancer. Some hypothesis suggests that Aspirin might play a role in the T cell-mediated anti-tumour activity.

While some public health organisations have started to give out recommendations to use this drug as preventative measures, there is still no consensus on how to involve this drug in a context with colorectal cancer.

Questions that need to be addressed:

  • Should it be used as a primary or secondary prevention?
  • Which age group should be targeted?
  • Which risk group will benefit the most?

About 5% of patients with colorectal cancer have a rare genotype that does not respond to Acetylsalicylic Acid, in fact, these patients have an increased risk of developing CRC when using Aspirin. Should each patient be checked for this rare genotype before a recommendation can be made?

What will the future bring?

I believe that the near future and further studies will provide some answers soon. In the meantime, I remain in awe of that little headache pill and how new benefits of Aspirin are still being discovered today. The notion of Aspirin as a wonder drug is becoming more than an advertising slogan.

Ketamine to treat depression

19/10/2017

There is a new light shining into the corner of treatment-resistant depression: in the form of a drug called Ketamine. This substance, not new to the medical world, is thought to have a rapid effect in clinical depression and could become a life-saver for people with severe suicidal depression.

The drug has hallucinogenic and pain relieving properties and is well known to anaesthetists for its use during the general anaesthetic. Commonly known as “horse tranquillizer”, due to its use in veterinary medicine, it is also a Saturday night drug for clubbers who appreciate the ‘out of body experience’ in its recreational use. Ketamine act on a receptor in the brain called NMDA. The exact mechanism of action related to major depressive disorder is not known yet. Although the effect of Ketamine kicks in much faster than conventional antidepressants, which take up to 3 weeks to show a mood enhancement, initial doses fade quickly and a regular treatment plan is needed to gain a long-term effect.

A substance called Esketamine, in the form of a nasal spray is currently going through phase III clinical trials and, if all goes well, could soon become a reality and a possible alternative to last resort Electroconvulsive therapy (ECT). Provided that side effects and long-term risks are causing any concerns, we could at long last be able to have an effective first aid treatment for major depression that acts safely and quickly.

A milestone in Oncology

10/10/2017

The future has begun

The FDA has just approved the first chimeric antigen receptor (CAR) T cell therapy offered by Novartis and the second licence for Kite’s CAR-T treatment is expected very shortly. Tisagenlecleucel-T, the product which Novartis calls Kymriah, has received clearance for use in paediatric and young adult patients (age 3 to 25 years) with relapsed or refractory acute lymphoblastic leukaemia (ALL).

Expectations for this new treatment in oncology are high and many patients refilled with hope; some medics go as far as to herald a new dawn in cancer therapy. Should we get excited about CAR-T or is it yet another cancer treatment for the record books of extortionate costs, ending up doing more harm than good?

CAR-T therapy is undoubtedly a novelty in cancer treatment. What makes it promising is that live cells are being used. What makes it unique is that each patients’ own cells are being used. What makes it revolutionary is the that these T cells are genetically engineered to fight cancer. Three high-tech approaches in one Therapy.

“A cell is more powerful to fight disease than any drug will ever be” – from this premise derive all endeavours in immunotherapy which have been driving the Research in T cell receptors since the late 80ies. Encouraging outcomes, however, have only been demonstrated in recent trials, reaching unanimous approval by the FDA. With rekindled interest in T cell therapy, investors are likely to open the money tap to exploit this avenue further.

The concept of T cell therapy

In most cancers, human cells have become malignant through several mutations, which prevent them from self-death (apoptosis) and promote them to uncontrolled multiplication, they have also managed to escape any immune response against them. They can hide from the immune system which does make sense, after all, they derive from tissue that is recognised as own. CD19 is a biochemical feature, or antigens to be precise, that is particular to the blood cancer called ALL. Tisagenlecleucel-T provides a receptor that binds explicitly (hence attacks) on the CD19 molecule.

How exactly is CAR-T therapy produced?

T cells are filtered out from the patient’s blood; a process called apheresis which is available in most clinics. These blood cells are sent to a specialised laboratory to be treated for 15 to 20 days before they return modified and multiplied.

Two major steps happen at the laboratory

First, the T cells are genetically engineered. In other words, a gene, which codes for a particular receptor (the chimeric antigen receptor), is inserted into the T cell’s DNA.

In a second step, these newly armoured T cells are multiplied into many million little fighters.

The finished treatment will undergo several stages of quality testing before it is ready for use

What are the side effects?

Tisagenlecleucel-T binds to all CD19 antigens; this receptor exists not only on cancerous B cells but also on healthy B cells. These play an essential role in fighting infection and producing antibodies against many communicable diseases. Treatment with Tisagenlecleucel-T can, therefore, cause an increase in infectious disease.

Other side effects that have been observed are CRS (cytokine release syndrome) and neurological disorders. CRS is is a type of systemic inflammatory response similar to that found in severe infection characterised by hypotension, pyrexia, and rigours. The patient feels unwell, as if in a state of high fever. It can be treated with the interleukin-6 antagonist tocilizumab. Neurological effects during the trial phase included encephalopathy, seizures, delirium, hallucinations, cognitive disorder, depressed conscious level of consciousness, mental status changes, muscular weakness, and dysarthria – all of them were reversible and could be treated with steroids.

What will the future bring?

By stepping into the commercial sphere, T cell therapy is consolidating its presence in oncology which will undoubtedly lead to further research, trials and investments.

CAR-T therapy might help to improve the tarnished reputation of ‘genetically modifying’.

Today, I am joining in the celebrations of this milestone and believe that CAR-T therapy will play a significant role in the future of cancer treatment. It will need further years of tweaking, but the prospect that one day a T cell receptor can be engineered to detect Antigens of an individual cancer fills me with enormous hope

China to accelerate drug approval

09/10/2017

According to recent news China is reporting that it intends to accelerate the approval process for new medication by accepting the data from international clinical trials. This is obviously great news for many patients in need of new generation drugs such as immunotherapy.

By adopting this more open approach, the world’s second-largest drug market is providing exciting news to the international Pharma industry. In the long run, however, this move will reassure the steady drive of many R&D departments around the world and be a springboard for China to become a serious player in the development of new medication.

Δiagnosis: stroke

02/10/2017

What is a stroke?

Also referred to as a cerebrovascular accident, a stroke is a sudden disruption of blood supply to an area of the brain, leading to damaged brain tissue. This disruption can either be caused by a blood clot (ischaemic), or it can be due to a burst blood vessel (haemorrhagic) in the brain.

Who is affected by strokes?

Two-thirds of all stroke patients are over the age of 65. Men and Afro-Caribbean are at higher risk of suffering a cerebrovascular accident; women tend to be older. Most risk factors that lead to a stroke are modifiable and are very similar to the cardiovascular red flags.

They include:

• High blood pressure

• Smoking or exposure to secondhand smoke

• High cholesterol

• Diabetes

• Obstructive sleep apnea

• Cardiovascular problems: heart failure or abnormal heart rhythm.

 

medical content
The darkened area on the left side represents the stroke.

How to treat strokes?

Dead brain cells cannot be replaced or regrow, and although our central nervous system has some compensation mechanism to reduce symptoms, the resulting neurological deficit will persist. Keeping in mind that during the acute phase of a stroke, the clinical picture is often exaggerated due to an inflammatory process affecting the functioning of healthy neighbouring brain cells which will recover over time. For many years stroke was an untreatable disease, focusing its management on prevention and rehabilitation.

New treatments during the very acute phase of an ischaemic stroke are available in many stroke units all over Europe today. It aims to reperfuse the affected brain area to limit the damage by using clot-busting medication (thrombolysis). Promising interventional methods are currently being tried out, where the clot gets mechanically removed with a catheter.

Many Western healthcare providers are taking part in Public stroke education and are highlighting the importance of acting quickly. The ‘FAST’ campaign has proved to be very successful in the UK and US to help recognise signs of a stroke; it uses the acronyms as follows:

• F: Face drooping

• A: Arm weakness

• S: Speech difficulty

• T: Time to call the emergency

How to avoid strokes?

The most important aspect in the management of cerebrovascular accidents is still its prevention which also shows some promising developments in recent years. Better control of high blood pressure and diabetes and a more aggressive anticoagulation (blood thinning) in patients with atrial fibrillation has contributed a great deal to this achievement. The introduction of more patient-friendly blood thinning medication for patients with atrial fibrillation will likely protect further from strokes in the future.

No Benefits of low-dose Oxygen during Acute Stroke

29/09/2017

To give or not to give Oxygen

In case of an emergency and if in any doubt, give the patient oxygen. This first aid manoeuvre is also part of a knee-jerk when attending to an acute cerebrovascular accident. To protect brain tissue from hypoxia with continuous oxygen during the acute phase of a cerebrovascular accident seems to be a good idea. That was the motivation behind the SOS study in the UK, an extensive randomised control study conducted in acute stroke units all over the country for ten years. Most doctors who worked on an acute stroke unit over the last 10 years probably remember this study which managed to recruit over 8000 patients.

The Outcomes of the SOS study

The results are out and show that there is no benefit in giving every stroke patient routine low dose Oxygen (2 to 3 L/min), either continuously or at night time, in the first few days after the event.

A similar outcome was recently seen in a large US study, where benefits of routine oxygen administration in patients with an acute myocardial infarct failed to materialise.

Providing that oxygen saturations are continuously monitored, less routine Oxygen during an acute event can only be a good thing. For the simple reason that it will alert healthcare workers of an occurring acute hypoxia more quickly and could provide life-saving time for diagnosis and treatment thereof.