India is the World Capital for many chronic diseases. Hypertension & diabetes are the initiation or starting point of many of these conditions, with the metabolic syndrome an intermediate & morbidity or disability due to chronic diseases like renal failure, retinal damage with vision loss or stroke as an end point.
Stroke as a word has come to mean cessation of nutrition via cessation of blood flow to any part of the body. When blood flow to the hearts own muscle stops it is called a Cardiac Stroke or a Heart Attack. When blood flow to the brain stops it is called a Neurological Stroke.
A neurological stroke is now called a BRAIN ATTACK so as to:
1) convey a similarity with heart attack as also
2) convey the URGENCY required to initiate treatment
Today, a stroke can be treated almost exactly like a heart attack and just as treating a heart attack urgently reduces the extent of damage spreading along the muscle tissue of the heart, urgently treating a stroke attempts to reduce the extent of damage along the tissues of the brain. The underlying pathology of a stroke can be either a block in flow of blood or bleeding in an artery of the brain. Both lead to similar outcome – a decrease in the supply of nutrition (oxygen & glucose) to that part of the brain. Because there can be two different paths – blockage or bleeding, the term CVA was coined.
The more broad term of Cerebrovascular disease (CVD) or Cerebro Vascular Accident (CVA) is used to include all disorders in which an area of the brain is transiently or permanently affected by ischemia or bleeding with one or more of the cerebral blood vessels being Involved In the pathological process. The word “Accident” attempts to denote the suddenness of the event & just like a vehicular accident. Early treatment may have a favorable outcome but not always, so also early treatment in a CVA may have a favorable outcome but not always. It is unto mankind to put systems into place to try achieve a favorable outcome in each and every accident.
Hippocrates (460 to 370 BC) was first to describe the phenomenon of sudden paralysis that is often associated with loss of blood supply. Apoplexy, from the Greek word meaning “struck down with violence,” first appeared in Hippocratic writings to describe this phenomenon.
Thompson JE (1996). “The evolution of surgery for the treatment and prevention of stroke. The Willis Lecture”. Stroke 27 (8): 1427.34,. PMID 8711815. Kopito, Jeff (September 2001). “A Stroke in Time”, MERGINET.com 6 (Number 9). The word stroke was used as a synonym for apoplectic seizure as early as 1599, and is a fairly literal translation of the Greek term.
In 1658, in his Apoplexia, Johannes Jakob Wepfer (1620.1695) identified the cause of hemorrhage as a cause of stroke when he suggested that people who had died of apoplexy had bleeding in their brains.
Wepfer also identified the main arteries supplying the brain, the vertebral and carotid arteries, and identified the cause of ischemic stroke [also known as cerebral infarction] when he suggested that apoplexy might be caused by a blockage to those vessels.
What is a Stroke?
Blood is carried to the brain via a complex network of arteries and vessels. A stroke occurs when one of these arteries becomes blocked or an artery ruptures resulting in sudden interruption in the blood supply of the brain. Strokes are caused by.
- an abrupt blockage of arteries leading to the brain -Ischemic stroke.
- by bleeding into brain tissue when a blood vessel bursts – Hemorrhagic stroke.
At times the symptoms of a stroke last only a short time (less than an hour); this is called a transient ischemic attack (TIA) or mini-stroke. Stroke has many consequences.
The effects of a stroke depend on which part of the brain is injured, and how severely it is injured. Strokes may cause
- Sudden weakness.
- loss of sensation.
- difficult with speaking, seeing, or walking.
Since different parts of the brain control different areas and functions, it is usually the area immediately surrounding the stroke that is affected. Sometimes people with stroke have a headache, but stroke can also be completely painless. It is very important to recognize the warning signs of stroke and to get immediate medical attention if they occur.
Carotid Artery distribution-carotid arteries perfuse the majority of the cerebrum
Common Carotid Artery ~ splits into the Internal Carotid Artery and the External Carotid Artery The Internal Carotid Artery ~ divides into the Anterior Cerebral Artery (ACA) and the Middle Cerebral Artery (MCA); both a left and right side are present.