Treatment for Unstable Angina
Patients diagnosed with unstable angina (an acute coronary syndrome) are admitted to the hospital for immediate treatment. Underlying conditions (e.g., hypertension, fever) are identified and treated. Most cases of unstable angina can be stabilized within 48 hours with medication.
Unstable angina may be treated intravenously with heparin for 3 to 5 days. In some cases, injectable low-molecular-weight heparin may be used. Aspirin may be given at the same time or after heparin therapy. Heparin is an anticoagulant that inactivates factors involved in blood clotting.
Heparin medications include enoxaparin (Lovenox®), dalteparin (Fragmin®), and nadroparin (Fraxiparin®). Frequent blood tests are needed to monitor the concentration of heparin in the blood.
Patients with evidence of damaged heart tissue or significant changes on ECG may also receive intravenous administration of a IIb/IIIa inhibitor to dissolve existing blood clots and to prevent new clot formation.
A beta blocker is administered and a calcium channel blocker may be added if symptoms persist. Nitroglycerin may be given under the tongue or intravenously for severe or prolonged episodes of angina.
If symptoms of unstable angina persist despite medication, cardiac catheterization and coronary angiogram may be recommended. Information obtained during these procedures may indicate that primary PTCA or coronary bypass grafting (CABG) is needed.
Patients with unstable angina undergoing coronary angioplasty frequently are treated with IIb/IIIa inhibitors (anticoagulants) during the procedure and for 12 to 24 hours afterward.
The IIb/IIIa inhibitors almost completely prevent the formation of blood clots and may help dissolve existing blood clots. Available IIb/IIIa inhibitors include eptifibatide (Integrelin®), tirofiban (Aggrastat®), and abciximab (ReoPro®). Adding these agents to standard treatment regimens for unstable angina may reduce the risk for unstable angina progressing to heart attack.
Variant angina, a form of unstable angina, is treated with nitroglycerin, given both under the tongue (sublingually) and intravenously, and nifedipine, a calcium channel blocker.