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Heart attacks are treated with cardiopulmonary
resuscitation (CPR) when necessary to start and keep the patient
breathing and his heart beating. Additional treatment can include
close monitoring, electric shock, drug therapy, re-vascularization
procedures, percutaneous transluminal coronary angioplasty and
coronary artery bypass surgery. Upon arrival at the hospital, the
patient is closely monitored. An electrical-shock device, a
defibrillator, may be used to restore a normal rhythm if the
heartbeat is fluttering uncontrollably. Oxygen is often used to ease
the heart's workload or to help victims of severe heart attack
breath easier. If oxygen is used within hours of the heart attack,
it may help limit damage to the heart.
Drugs to stabilize the patient and limit damage to the heart include
thrombolytics, aspirin, anticoagulants, painkillers and
tranquilizers, beta-blockers, ace-inhibitors, nitrates, rhythm-stabilizing
drugs, and diuretics. Drugs that limit damage to the heart work only
if given within a few hours of the heart attack. Thrombolytic drugs
that break up blood clots and enable oxygen-rich blood to flow
through the blocked artery increase the patient's chance of survival
if given as soon as possible after the heart attack. Thrombolytics
given within a few hours after a heart attack are the most effective.
Injected intravenously, these include anisoylated plasminogen
streptokinase activator complex (APSAC) or anistreplase (Eminase),
recombinant tissue-type plasminogen activator (r-tPA, Retevase, or
Activase), and streptokinase (Streptase, Kabikinase).
To prevent additional heart attacks, aspirin and an anticoagulant
drug often follow the thrombolytic drug. These prevent new blood
clots from forming and existing blood clots from growing.
Anticoagulant drugs help prevent the blood from clotting. The most
common anticoagulants are heparin and warfarin. Heparin is given
intravenously while the patient is in the hospital; warfarin, taken
orally, is often given later. Aspirin helps to prevent the dissolved
blood clots from reforming.
To relieve pain, a nitroglycerine tablet taken under the tongue may
be given. If the pain continues, morphine sulfate may be prescribed.
Tranquilizers such as diazepam (Valium) and alprazolam (Ativan) may
be prescribed to lessen the trauma of a heart attack.
To slow down the heart rate and give the heart a chance to heal,
beta-blockers are often given intravenously right after the heart
attack. These can also help prevent the sometimes fatal ventricular
fibrillation. Beta-blockers include atenolol (Tenormin), metoprolol
(Lopressor), nadolol, pindolol (Visken), propranolol (Inderal), and
timolol (Blocadren).
Nitrates, a type of vasodilator, are also given right after a heart
attack to help improve the delivery of blood to the heart and ease
heart failure symptoms. Nitrates include isosorbide mononitrate (Imdur),
isosorbide dinitrate (Isordil, Sorbitrate), and nitroglycerin (Nitrostat).
When a heart attack causes an abnormal heartbeat, arrhythmia drugs
may be given to restore the heart's normal rhythm. These include:
amiodarone (Cordarone), atropine, bretylium, disopyramide (Norpace),
lidocaine (Xylocaine), procainamide (Procan), propafenone (Rythmol),
propranolol (Inderal), quinidine, and sotalol (Betapace).
Angiotensin-converting enzyme (ACE) inhibitors reduce the resistance
against which the heart beats and are used to manage and prevent
heart failure. They are used to treat heart attack patients whose
hearts do not pump well or who have symptoms of heart failure. Taken
orally, they include Altace, Capoten, Lotensin, Monopril, Prinivil,
Vasotec, and Zestril. Angiotensin receptor blockers, such as
losartan (Cozaar) may substitute. Diuretics can help get rid of
excess fluids that sometimes accumulate when the heart is not
pumping effectively. Usually taken orally, they cause the body to
dispose of fluids through urination. Common diuretics include:
bumetanide (Bumex), chlorthalidone (Hygroton), chlorothiazide (Diuril),
furosemide (Lasix), hydrochlorothiazide (HydroDIRUIL, Esidrix),
spironolactone (Aldactone), and triamterene (Dyrenium).
Percutaneous transluminal coronary angioplasty and coronary artery
bypass surgery are invasive revascularization procedures which open
blocked coronary arteries and improve blood flow. They are usually
performed only on patients for whom clot-dissolving drugs do not
work, or who have poor exercise stress tests, poor left ventricular
function, or ischemia. Generally, angioplasty is performed before
coronary artery bypass surgery.
Percutaneous transluminal coronary angioplasty, usually called
coronary angioplasty, is a non-surgical procedure in which a
catheter (a tiny plastic tube) tipped with a balloon is threaded
from a blood vessel in the thigh or arm into the blocked artery. The
balloon is inflated and compresses the plaque to enlarge the blood
vessel and open the blocked artery. The balloon is then deflated and
the catheter is removed. Coronary angioplasty is performed by a
cardiologist in a hospital and generally requires a two-day stay. It
is successful about 90% of the time. For one third of patients, the
artery narrows again within six months after the procedure. The
procedure can be repeated. It is less invasive and less expensive
than coronary artery bypass surgery.
In coronary artery bypass surgery, called bypass surgery, a detour
is built around the coronary artery blockage with a healthy leg or
chest wall artery or vein. The healthy vein then supplies oxygen-rich
blood to the heart. Bypass surgery is major surgery appropriate for
patients with blockages in two or three major coronary arteries or
severely narrowed left main coronary arteries, as well as those who
have not responded to other treatments. It is performed in a
hospital under general anesthesia using a heart-lung machine to
support the patient while the healthy vein is attached to the
coronary artery. About 70% of patients who have bypass surgery
experience full relief from angina; about 20% experience partial
relief. Long term, symptoms recur in only about three or four
percent of patients per year. Five years after bypass surgery,
survival expectancy is 90%, at 10 years it is about 80%, at 15 years
it is about 55%, and at 20 years it is about 40%.
There are three experimental surgical procedures for unblocking
coronary arteries which are currently being studied: atherectomy,
where the surgeon shaves off and removes strips of plaque from the
blocked artery; laser angioplasty, where a catheter with a laser tip
is inserted to burn or break down the plaque; and insertion of a
metal coil called a stent that can be implanted permanently to keep
a blocked artery open. |
