Stroke unstruck

Dr Rahul Oinam *

Stroke is a neurological disease caused by sudden interruption of blood supply to a part of the brain causing loss of some function of the brain. The word stroke is derived from the notion of the disease being apparently caused by a sudden ‘stroke of the hand of God’ due to the abruptness of symptoms.

A majority of this is due to sudden clogging of blood vessels (also known as ischemic stroke) while the remaining occurs due to bleeding in the brain (aka hemorrhagic stroke).

Most ischemic strokes occur due to atherosclerotic thickening of blood vessels or embolization of blood clot either from atherosclerotic plaque in a large artery or from the heart. Less commonly the cause can be dissection of neck vessels, inflammation of blood vessels, increased blood thickness due to certain diseases, drug abuse or certain rare hereditary diseases.

On the other hand, the most common cause of hemorrhagic stroke is bursting of small blood vessels due to high blood pressure. Certain blood vessel wall disorders including amyloid angiopathy, diseases predisposing to increased bleeding are other causes; rarely they can be due to vessel malformations or tumors.

Stroke is a common disease, with one in four people affected over their lifetime, and is the second leading cause of death and third leading cause of disability in adults worldwide. The key clinical feature of stroke is the suddenness of onset and the unilateral nature of symptoms like paralysis or numbness restricted to one side of the body.

However sometimes symptoms can be non lateralizing like slurring of speech, inability to speak or comprehend, vertigo, imbalance or loss of consciousness. It may also be worth mentioning that not all sudden symptoms are due to stroke.

Seizures, certain types of migraine, very low blood sugar, psychological disorders and even space-occupying lesions in the brain like tumors can mimic stroke. In certain patients with previous stroke, the previous neurological deficit can sometimes transiently return with intercurrent illness.

As soon as a person is suspected to have a stroke, he/she should be taken to a hospital that is stroke ready without wasting a moment. Care should be taken to prevent aspiration in case of lack of consciousness by keeping in an upright or semi reclining position or lying laterally on one side. Administering antihypertensive at home is not advisable.

Substantial advances in therapy have occurred in the past 5 years, particularly for the acute treatment of ischemic stroke. Advent of intravenous thrombolysis and mechanical thrombectomy have revolutionised ischemic stroke treatment. However these procedures are restricted to only a few hours after stroke onset. Intravenous thrombolysis uses injection of blood thinning agents to clear up the clots.

It is approved to be used within 4.5 hours of stroke and slightly longer in select patients. Mechanical thrombectomy involves endovascular intervention to remove clots in patients of ischemic stroke due to occlusion of larger vessels. It is approved for use in the first 6 hours of stroke or slightly longer in select patients and is available in only a few centers.

Life saving surgeries are often required in large ischemic and hemorrhagic strokes. Admission in a dedicated stroke care unit ultimately increases survival and recovery of stroke patients. Stringent blood pressure management, neuroprotective therapy, preventing complications, early rehabilitation affect outcomes in a big way. Stroke etiology work up and targeted secondary prevention are major parts of stroke care.

Approximately 90% of strokes are attributable to modifiable risk factors. Stroke shares many risk factors with other cardiovascular diseases. The most potent risk factor for stroke is high blood pressure, which applies to both ischemic stroke and hemorrhagic stroke.

Tobacco use, diabetes mellitus, high blood cholesterol, and physical inactivity are also significant risk factors. About one third of ischemic stokes are attributed to cardiac problems with atrial fibrillation, a rhythm abnormality of the heart, being a major cause.

Rehabilitation is a major part of stroke. Barring few patients with minor strokes, most stroke patients need rehabilitative therapy. Major interventions include occupational therapy, physical therapy, speech and language therapy.

This is another evolving field with promising roles in virtual reality, robotics, Transcranial magnetic stimulation and stem cell therapy besides the doubtless benefit of conventional rehabilitation therapies. Often ignored, the role of rehabilitation surpasses acute stroke intervention as of this day.

Another neglected aspect of stroke care is psychological support. From loss of function to loss of livelihood to caregiver burden, patients ultimately go into depression and other psychological problems. Psychosocial support is an important part of rehabilitation.

Let us learn to identify a stroke and seek medical care in time. Let us also pledge to be empathetic to our stroke survivors as they are our own parents and elders who once taught us to walk and be independent. We must feel fortunate to be able to return the favor to them and help them walk again.