Heart Disease
More than a million
Indian have heart attacks each year. A heart attack, or myocardial infarction (MI), is
permanent damage to the heart muscle. "Myo" means muscle, "Cardial"
refers to the heart, and "infarction" means death of tissue due to
lack of blood supply.
What Happens During
a Heart Attack?
The heart muscle
requires a constant supply of oxygen-rich blood to nourish it. The coronary
arteries provide the heart with this critical blood supply. If you have
coronary artery disease, those arteries become narrow and blood cannot flow as
well as they should. Fatty matter, calcium, proteins, and inflammatory
cells build up within the arteries to form plaques of different sizes. The
plaque deposits are hard on the outside and soft and mushy on the inside.
When the plaque is
hard, the outer shell cracks (plaque rupture), platelets (disc-shaped particles
in the blood that aid clotting) come to the area, and blood clots form around
the plaque. If a blood clot totally blocks the artery, the heart muscle becomes
"starved" for oxygen. Within a short time, death of heart muscle
cells occurs, causing permanent damage. This is a heart attack.
While it is
unusual, a heart attack can also be caused by a spasm of a coronary artery.
During a coronary spasm, the coronary arteries restrict or spasm on and off,
reducing blood supply to the heart muscle (ischemia). It may occur at rest, and
can even occur in people without significant coronary artery disease.
Each coronary
artery supplies blood to a region of heart muscle. The amount of damage to the
heart muscle depends on the size of the area supplied by the blocked artery and
the time between injury and treatment.
Healing of the
heart muscle begins soon after a heart attack and takes about eight weeks. Just
like a skin wound, the heart's wound heals and a scar will form in the damaged
area. But, the new scar tissue does not contract. So, the heart's pumping
ability is lessened after a heart attack. The amount of lost pumping ability
depends on the size and location of the scar.
Heart Attack
Symptoms
Symptoms of a heart
attack include:
·
Discomfort, pressure, heaviness, or pain in the chest, arm, or below the
breastbone
·
Discomfort radiating to the back, jaw, throat, or arm
·
Fullness, indigestion, or choking feeling (may feel like heartburn)
·
Sweating, nausea, vomiting, or dizziness
·
Extreme weakness, anxiety, or shortness of breath
·
Rapid or irregular heartbeats
During a heart
attack, symptoms last 30 minutes or longer and are not relieved by rest or nitro-glycerine under the tongue.
Some people have a
heart attack without having any symptoms (a "silent" myocardial
infarction). A silent MI can occur in anyone, but it is more common among
people with diabetes.
