Prior to Undergoing Angioplasty
Before angioplasty, physicians should be notified if the patient has an allergy to shellfish or intravenous dye, or has diabetes or kidney disease. These patients may not tolerate the iodine-based dye used in angioplasty, and an agent that carries less risk for severe allergic reaction or kidney failure may be used.
High-risk patients (e.g., those with unstable angina, diabetes, kidney disease) may be admitted to the hospital the night before the procedure to receive intravenous hydration and a steroid to lower the risk for complications.
Angioplasty patients often are given aspirin or another drug at least 2 hours before the procedure. Aspirin-sensitive patients may be given another antiplatelet, such as ticlopidine or clopidogrel (Plavix). In June 2015, the U.S. Food and Drug Administration (FDA) approved cangrelor (Kengreal) to prevent the formation of blood clots in the coronary arteries in adults undergoing percutaneous coronary intervention.
Side effects of ticlopidine include diarrhea, rash, nausea, vomiting, abdominal pain, and neutropenia (low white blood cell count). Clopidogrel is usually tolerated as well as aspirin. In a small number of cases, thrombocytopenia purpura may develop and patients receiving clopidogrel should be monitored for this during the procedure. Cangrelor carries a higher risk for serious bleeding, but that risk is still considered low. Research shows this drug also significantly reduces heart attack risk and the need for additional PCI procedures.
An IV is started to administer medication that helps prevent blood clot formation during and after the procedure. Anticoagulants include heparin, which is given alone or, if the patient has unstable angina or other high-risk factors, with GP IIB/IIIA receptor inhibitors (e.g., abciximab, tirofiban) and bivalirudin (Angiomax®). Angiomax is administered in combination with aspirin therapy in some patients. These agents lower the risk for blood clot formation and the complications they may cause.
Angioplasty is performed in a catheterization laboratory equipped with x-ray equipment and monitors. Before going into the catheterization lab, a mild sedative is given to the patient and the insertion area may be shaved.
In the catheterization lab, the insertion area is cleansed with a sterilizing solution, covered with sterile drapes, and numbed with a local anesthetic.
An incision is made and a pencil-sized plastic sheath is inserted. Flexible catheters are passed through the sheath to the blocked coronary artery. The devices used to open the artery (e.g., balloon, laser, burr) are advanced to the blockage through the catheters.
An iodine-based dye or other contrast agent is injected to make the arteries and blockage(s) visible on a monitor. Physicians use a monitor to guide them during the procedure.