M
medications to treat cardiovascular diseaseDrugs
that alter the function of the HEARTor the BLOOD
vessels. Plants provided the earliest forms of DRUG
therapy for heart problems. Healers in ancient
Egypt and Greece brewed teas of foxglove leaves,
the source of digitalis, to slow a rapid heartbeat and
strengthen a weakened heart. By the 17th century
physicians were using a relatively standardized for-
mulation of powdered foxglove to treat congestive
HEART FAILURE. Foxglove leaves remain the source
from which laboratories extract digitalis to manu-
facture digoxin and digitoxin, the digitalis-based
medications that remain in use today. Quinidine, a
medication to treat ARRHYTHMIA(irregular heart-
beat), derives from the bark of the South American
Cinchona ledgerianatree (also the original source of
the antimalarial drug quinine). Scientists isolated
quinidine as an extract to treat ATRIAL FIBRILLATIONin
- Rauwolfia serpentinawas a staple in the PHAR-
MACOPOEIAof healers in ancient India, who used its
dried roots to lower BLOOD PRESSURE. The antihyper-
tensive medication reserpine, which debuted in the
1950s, contains Rauwolfiaalkaloid extracts. Today
medications are the mainstay of treatment for most
forms of CARDIOVASCULAR DISEASE(CVD), though most
are synthetic formulations that come from the lab-
oratory.
Cardiovascular disease often involves multiple,
interrelated components. HYPERTENSION(high blood
pressure) often arises from underlying ATHEROSCLE-
ROSIS, the most common cardiovascular disease.
CORONARY ARTERY DISEASE(CAD), a manifestation of
atherosclerosis that affects the CORONARY ARTERIES
supplying the heart, may generate arrhythmias and
ANGINA PECTORIS. Heart failure typically features
numerous symptoms arising from a constellation of
cardiovascular dysfunctions. The recent direction of
research has correspondingly produced medica-
tions that treat the constellation, not just a single
symptom. A calcium channel blocker, a classifica-
tion of medication that debuted in the 1990s,
dilates peripheral arteries, and slows the HEART RATE;
these actions lower blood pressure, regulate the
heart’s rhythm, and strengthen the heart’s pump-
ing action. Combining medications often produces
more effective results. For example, the cardiologist
may also prescribe a diuretic to extract additional
fluid from the body, which lowers blood volume
and thus blood pressure, which in turn relieves the
heart’s workload to reduce heart failure. The com-
bination of the diuretic and the calcium channel
blocker may restore nearly normal cardiovascular
function.
People respond differently to cardiovascular
drugs, even when they have the same diagnoses.
It may take a trial and error period to find the
right medication or combination of medications
for each individual. Cardiovascular medications
may interact or interfere with each other, with
medications for other health conditions, with
herbal preparations, and with certain foods. For
example, grapefruit (whole fruit or juice) inter-
feres with the actions of calcium channel blockers,
statin lipid-lowering medications, digoxin, potas-
sium channel blockers, and warfarin. The herb
GOLDENSEAL, taken to enhance immune function,
elevates blood pressure and interacts with antihy-
pertensive medications. Dark green leafy vegeta-
bles contain VITAMINK, which increases clotting
and interferes with anticoagulant medications.
Most medications to treat cardiovascular condi-
tions have the potential for side effects, some of
which may be life-threatening. Sodium channel
and potassium channel blockers, digoxin, war-
farin, and heparin all are NARROW THERAPEUTIC
INDEX(NTI) drugs, for which the margin between76